Collective Actions for Environment

Climate Change Challenge: Why Population is Important

2011-04-25T00:10:00.000-07:00

Climate change is one of the greatest challenges facing humanity in the 21st century. Most environmental problems, including those arising from climate change, are aggravated by population growth. Thus, the fact that the world's population has surpassed 6.7 billion and continues to grow by some 78 million additional people each year presents enormous challenges.

Making a clear and direct linkage between population change and climate change is complex because the effects of human activity on emissions are the product of a range of driving forces, including economic growth, technological changes, and population growth.
A growing body of evidence shows that recent climate change is primarily the result of human activity. Evidence suggests that the poorest countries and population groups are most vulnerable to climate change impacts. Population growth is occurring most rapidly in the developing world, increasing the scale of vulnerability to projected impacts of climate change. Other demographic trends, such as urbanization in coastal areas and encroachment of populations into ecologically marginal areas, can exacerbate climate risks. Population growth is already putting a strain on the world’s limited supply of fresh water. Without taking into account the projected impacts of climate change, five billion people more than half the world’s populations are expected to live in water stressed countries by 2050.

The impacts of extreme weather events and projected sea level rise are particularly significant due to high population density on and near coastlines and low-elevation zones. In Bangladesh and China, for example, populations living in low elevation coastal zones grew at almost twice the national population growth rate between 1990-2000 exposing disproportionately growing numbers of people to the negative effects of sea-level rise and extreme weather.

Under middle range projections of population growth, agricultural production loss and an increase in the prices of crops due to climate change will lead to an additional 90 to 125 million people at risk of hunger in the developing world by 2080. In Bangladesh, on more than 25,000 hectares of land in the south, agricultural production has dropped significantly in recent years. Most of the affected area is less than 1.5m above sea level and due to sea level rise, 13.74 percent of net cropped area and about 401,600 hectares of mangrove forest along with its wild life will be vanished.

In 2005, the average population density in developing countries was 66 people/km2, which is more than double in developed regions (27 people/km2). Under high population pressure, a large share of the population in the developing world is already living in marginalized areas, which are susceptible to climate variation and extreme weather events. For instance, around one-sixth of the world’s population is living in arid and semi-arid regions; more than 250 million people are directly affected by desertification, while another one billion are at risk. The world’s major arid regions are in the developing world, where the population growth rate is high, and socio-development levels are low.

Poor and vulnerable populations are those living in places exposed to climate risks, heavily dependent on climate for survival, and who have fewer resources to cope with the adverse impacts of climate change. For example, 70 percent of the African population relies on rain-fed agriculture for their livelihoods, and a slight shift in rainfall patterns or temperature can be disastrous.
It was found by Intergovernmental Panel on Climate Change (IPCC) that higher population growth projections generally result in more GHG emissions. The Population assumptions range widely, from a low population projection of 7.1 billion to a high of 15 billion in 2100. For example, the effects of highly carbon-intensive economic growth and technological change can be more substantial than population growth on future carbon emissions, at least for several decades.
A weakness of the IPCC’s current scenarios is that population size is the only demographic variable considered; no allowances are made for compositional changes within the population as it grows. Energy consumption patterns differ between rural and urban populations, between younger and older populations, and between households with many people versus households with fewer. The world is becoming increasingly urban and older, and household sizes are becoming smaller but these changes have not yet been accurately accounted for in climate change models. The majority of future population growth is likely to occur in areas of the world that are already beginning to experience climate change impacts, and this growth is likely to be concentrated in areas and among populations—poor, urban, and coastal—that are already highly vulnerable to climate change impacts.
Many of the policies that affect population trends, such as meeting the demand for family planning nd reproductive health services among the world’s women and families, can play an important role in climate change adaptation and mitigation, but have not yet been incorporated into comprehensive climate change solutions.

Combating climate change calls for the spirit of environmental stewardship and international cooperation on a range of emissions reduction and adaptation approaches. These approaches will benefit from greater attention to population dynamics, including growth, household structure, urbanization and aging. Population policies and programs that promote universal access to voluntary contraception, when linked with broader efforts to address a range of demographic factors and meet development and poverty reduction objectives, such as the MDGs, will help lead to a more sustainable demographic future that will play a crucial role in climate change mitigation and adaptation.

Wetlands, Climate Change Impact and Adaptation

2011-04-24T23:55:00.000-07:00

The term global climate change conjures up different images to each of us, depending on a variety of factors such as our geographic location and our lifestyle. Based on its research, the IPCC concludes that "human activities, including the burning of fossil fuels, land-use change and agriculture, are increasing the atmospheric concentrations of greenhouse gases (which tend to warm the atmosphere) and, in some regions, aerosols (microscopic airborne particles, which tend to cool the atmosphere), are projected to change regional and global climate and climate elated parameters such as temperature, precipitation, soil moisture and sea level."

While currently the number one driver of wetland loss and degradation is habitat change as a result of human development, climate change effects are already being felt across the world. As our understanding of climate change increases, there is a new sense of urgency about the state of wetland species and ecosystems: clearly, climate change will become one of the major drivers of ecosystem loss during this century and will intensify the impacts of the other drivers.

In general, wetlands found in prairies, tropical and boreal forests, arctic and alpine ecosystems, and coral reefs and mangroves are thought to be especially vulnerable to climate change because they have a limited capacity to adapt to change - damage to these ecosystems may be irreversible.

Expected increases in sea surface temperature of about 1-3°C are likely to result in more frequent coral bleaching events and widespread mortality of corals. Coastal wetlands including salt marshes and mangroves are likely to be negatively affected by sea-level rise, especially where there are physical barriers on their landward side; increased damage from coastal flooding through storms and tidal surges will take place in many areas.

Changes in the timing and volume of fresh water run-off from inland wetlands will affect salinity, nutrient availability, and moisture regimes in coastal ecosystems – all of which will have an impact on coastal ecosystem functions. Many low-lying islands, particularly those in the Pacific, Indian and Atlantic Oceans and the Caribbean Sea, are likely to be at risk of being submerged.

Changes in rainfall intensity and variability are expected to increase flooding and drought in many areas. In general, precipitation increases are expected in high latitudes and parts of the tropics and decreases in some sub-tropical and lower mid-latitude regions (some of these latter areas are already water stressed). Some climate models predict that by 2050, annual average river runoff and water availability are projected to increase by 10-40% at high latitudes and in some wet tropical areas, and decrease by 10-30% over some dry regions at mid-latitudes and in the dry tropics. Higher water temperatures and extreme weather events (such as floods and droughts) are projected to affect water quality and to intensify many forms of water pollution – pollutants such as high nutrient levels, pathogens, pesticides, salt, etc.

Nearly 2 billion people already live in areas of high flood risk, often as a result of destruction of floodplain wetlands and reclamation for agriculture and urban development; further losses of wetlands in these areas, along with the impact of climate change in certain latitudes, increases this vulnerability. The impacts of floods are many – quite aside from the immediate effects of human mortality there is the risk of infectious diseases, and there is evidence of equally negative impacts of climate-related effects on mental health, resulting in long-term depression and anxiety.

Around 50% of the world’s people live along the coast and the density of populations in coastal area is three times higher than the global average. Many of the world’s poorest communities are coastal dwellers and rely on mangrove and reef-based fisheries for food security.

In developing countries, coral reefs contribute about a quarter of the annual fish catch, providing food for about one billion people in Asia alone; in Indonesia, for example, some 60% of the population is dependent on marine and coastal fishing resources for food and livelihoods. The Great Barrier Reef contributes a total of US$ 4.5 billion to the Australian economy, with US$3.9 billion from tourism, US$469 million from recreation, and US$115 million from commercial fishing, collectively generating 63,000 jobs.

Broadly there are a number of key responses that can be made to resolve the loss of wetland biodiversity and the additional impacts of climate change on those losses:

· Maintain the health of our intact wetlands;

· Redouble efforts to address the key drivers of wetland loss and degradation (habitat loss, pollution, excessive water withdrawals, invasive species, overexploitation, etc.);

· Continue to identify vulnerable species and ecosystems, and plan and implement species and ecosystem action plans for recovery;

· Priorities and plan wetland management and restoration programmes for a changing and more variable climate; managers will have to adapt their planning to take account of these changes with the aim of maintaining as far as possible the delivery of ecosystem services;

· Continue to restore degraded wetlands, since healthier wetlands are more resilient than degraded ones; and urgently address the additional impact of climate change on wetland species and ecosystems through:

· Climate change mitigation actions;

· Appropriate climate change adaptation strategies.

Mitigation requires us to reduce greenhouse gas emissions and to encourage the removal of such gases already in the atmosphere, ‘trapping’ them in soils and vegetation. There is no question that the key culprit globally in CO2 emissions is our use of fossil fuels. But we can also have a real impact on emissions by the way we manage our environment. Especially significant are the continuing rapid rates of deforestation of wetland and other forests and the draining of peat lands. Peat lands, though covering only 3% of global land area, have long been recognized as an important carbon sink, and their drainage and conversion for other uses as an important source of emissions. There is also increasing evidence of the role of mangroves, salt marshes and other wetlands as carbon sinks, and thus there is an urgent need to restore and secure the management of these wetlands as well.

For this Ecosystem-based adaptation is the best to climate change delivers this holistic approach. For inland wetlands, it requires actions to:

· Reduce the degradation of river basins by deforestation;

· Increase afforestation;

· Maintain and restore riparian wetlands and floodplains along rivers so that they can provide better protection from flooding;

· Improve management of wetlands and water at the basin level;

· Restore “green infrastructure” wherever possible: the natural flood defense system provided by inland wetlands will help to ensure that the other ecosystem services provided by wetlands are maintained.

Ecosystem-based adaptation in coastal ecosystems requires actions to:

· Reduce the loss and degradation of, mangroves, salt marshes, sand dunes, coral and shellfish reefs and other coastal wetlands, and restore them where possible, to produce ecosystems more resilient against sea level rise;

· Minimize “hard” infrastructure developments against coastal floods in favor of green infrastructure wherever possible;

· Remove artificial barriers on the landward side of mangroves and salt marshes so that they may be able to migrate landwards as sea levels rise.

Agriculture: A Most Vulnerable Sector due to Climate Change

2011-04-24T10:27:00.000-07:00

Environment is constantly changing. With increased technical capabilities man changes his surrounding faster than ever before. However, mankind is aware that fast climate changes (anthropogenic and/or natural) have impacts on many aspects of life. The most direct economical influence of global climate change is due to its direct impact on agriculture and crop yields. Increased intensity and frequency of storms, drought and flooding, altered hydrological cycles and precipitation variance have implications for future food availability, some coastal food-producing areas will be inundated by the seas, and food production will fall in some places in the interior.

In developing countries, 11 percent of arable land could be affected by climate change, including a reduction of cereal production in up to 65 countries, about 16 percent of agricultural GDP (FAO Committee on Food Security, Report of 31st Session, 2005).

A study published in Science suggest that, due to climate change, "Southern Africa could lose more than 30% of its main crop, maize, by 2030. In South Asia losses of many regional staples, such as rice, millet and maize could top 10%".

The 2001 IPCC Third Assessment Report concluded that the poorest countries would be hardest hit, with reductions in crop yields in most tropical and sub-tropical regions due to decreased water availability, and new or changed insect pest incidence.

In the long run, the climatic change could affect agriculture in several ways:

· Productivity in terms of quantity and quality of crops

· Agricultural practices, through changes of water use (irrigation) and agricultural inputs such as herbicides, insecticides and fertilizers.

· Environmental effects, in particular in relation of frequency and intensity of soil drainage (leading to nitrogen leaching), soil erosion, reduction of crop diversity.

· Rural space, through the loss and gain of cultivated lands, land speculation, land renunciation, and hydraulic amenities.

· Adaptation, organisms may become more or less competitive, as well as humans may develop urgency to develop more competitive organisms, such as flood resistant or salt resistant varieties of rice.

The earth's average temperature has been rising since the late 1970s, with nine of the 10 warmest years on record occurring since 1995. In 2002, India and the United States suffered sharp harvest reductions because of record temperatures and drought. Similarly, because of higher temperatures and humidity, there could be an increased pressure from insects, fungal diseases and disease vectors. Studies have shown that higher CO₂ levels lead to reduced plant uptake of nitrogen resulting in crops with lower nutritional value. This would primarily impact on populations in poorer countries less able to compensate by eating more food, more varied diets, or possibly taking supplements.

Climate change could have a particularly severe impact on South Asia, where a large proportion of the region’s population depends on subsistence agriculture for their livelihoods.

Agricultural crop of Bangladesh is influenced by seasonal characteristics and different variables of climate such as temperature, rainfall, humidity, day-length etc. It is also often constrained by different disasters such as floods, droughts, soil and water salinity, cyclone and storm surges. Several studies indicated that climate is changing and becoming more unpredictable every year in Bangladesh. Flood and water logging in the central region, flash-flood in the northeast region, drought in the northwest and southwest region, and salinity intrusion and coastal inundation in the coastal regional would be a more acute problem in future. All of these will have an extra bearing on the agriculture sector.

Different models predict different level of impacts for yield reduction under different climate change scenarios. The GFDL model predicted about 17 % decline in overall rice production for Bangladesh and as high as 61% decline in wheat production under 4 degree changes in temperature. The highest impact would be on wheat followed by rice (Aus variety). Of the three varieties of rice grown in Bangladesh, the Aus rice (grown during the summer, monsoon period under rain-fed conditions) seems to be the most vulnerable. The temperature impact already seen in this season in different region of Bangladesh. It is predicated that rice production will decrease in this year and people will face serious food crisis and economic loss. “We need more extensive climate research in different agroeconomic zone in Bangladesh to get actual adaptation in the context of local environment” stated Dr. Syed Hafizur Rahman, Chairman, Department of Environmental Sciences, Jahangirnagar University.

Climate change is obvious thing, so adaption is very much important in Bangladesh to overcome the food crisis and economic loss by cost-effective ways to help poor farmers, Provide funds for infrastructure and institutional innovations, Provide funds for agricultural science and technology, allow funding mechanisms that recognize the connection between pro-poor development policies for sustainable growth and sound climate change policies, allow funding mechanisms that recognize and support synergies between adaptation and mitigation etc.

Water crisis- A crucial issue to concern

2011-04-24T10:09:00.000-07:00

Water pervades all aspects of human development and human freedom. Water security is an integral part of this broader conception of human security. In broad terms water security is about ensuring that every person has reliable access to enough safe water at an affordable price to lead a healthy, dignified and productive life, while maintaining the ecological systems that provide water and also depend on water. When these conditions are not met, or when access to water is disrupted, people face acute human security risks transmitted through poor health and the disruption of livelihoods and vulnerability.

While the world's population tripled in the 20th century, the use of renewable water resources has grown six-fold. Within the next fifty years, the world population will increase by another 40 to 50 %. This population growth - coupled with industrialization and urbanization - will result in an increasing demand for water and will have serious consequences on the environment.

Worldwide, over a billion people do not have access to safe drinking water, and approximately one-third of the world’s population lives under water stress. Water stress results from an imbalance between water use and water resources. Water stress causes deterioration of fresh water resources in terms of quantity (aquifer over-exploitation, dry rivers, etc.) and quality (eutrophication, organic matter pollution, saline intrusion, etc.)
Humans use water in many ways, and we typically classify water use by three major use groups: agriculture, industry, and urban use. These are generally considered the three principal consumers of water, with most water consumed by agriculture for the production of food. However, there is also a fourth group; ecosystems also have water needs and requirements. Each river and lake requires a certain amount of water to continue to exist, and plants and animals require water for their survival too. This fourth need is often overlooked as we work to meet the immediate day-to-day water needs of humankind. However, its importance is becoming apparent as rivers are suffering from reduced flow or no flow before they reach the ocean, and fresh water dependent ecosystems are being compromised. Ultimately, our sustainable future on Earth is linked to the health of Earth’s ecosystems.

Currently, per capita availability of freshwater is decreasing and contaminated water is still the greatest environmental cause of human sickness and death.Water resources are being threatened by increased consumption, increased pollution, and increasing population. These threats are likely to become worse during our lifetimes and those of our children. Specifically, we will have to be concerned about:
• Surface water and groundwater availability
• Surface water and groundwater quality
• Water related diseases
• Water availability for irrigation and food production
• Water for urban use, drinking, and sanitation
• Water for industry, to make the things we need

• Damming of rivers: the benefits versus the ecological and human costs Changing climate/weather patterns
• International problems/violence caused by water stress and water-related ecosystem damage

By 2025, two-thirds of the world’s people are expected to be living in water stressed countries. Most of these people will live in Asia and Africa where water-related diseases are endemic and increase every year. Over 5 million people now die annually from water related diseases such as diarrhea, malaria, and schistosomiasis (bilharzia). In addition, trachoma, a highly contagious eye disease, blinds many more.
Population growth creates an obvious threat to what little remaining water is left for human use. Africa and Asia are currently the most water stressed areas, and since these two continents also have the greatest population growth, their already severe water stress will likely continue to increase. This explosion of water stress will be caused by increased personal water usage as a result of a 40 percent population growth in these countries, increased water use in irrigation for food production (17 percent), and increased water use in industrial production.
Global economic growth is both expected and hoped for because poverty is rife across the world, but under current trends, economic growth, coupled with population growth, will lead to drastic increases in the demand for natural resources, including water. Growth in agriculture, industries and energy producers will greatly increase water demand. In addition, as people's standard of living increases, they tend to use more water in
dishwashers, washing machines, swimming pools, car washes, etc. The resulting competition for water could be devastating for many people.

Since the 1990s, international efforts to improve water policy have increased, especially through growing recognition of the social and economic value of water. Water councils and global organizations are meeting and passing resolutions to protect water resources. The Water Supply and Sanitation Collaborative Council (WSSCC) set such resolutions at the Second World Water Forum in 2000. The Vision sets out targets: (1) to cut “the proportion of people without access to hygienic sanitation” in half by 2015; (2) to cut “the proportion of people without access to adequate quantities of affordable and safe water” in half by 2015; and (3) to “provide water, sanitation and hygiene for all” by 2025.

In 1998, the International Network of Basin Organizations met and emphasized the need to (1) facilitate the exchange of accurate and harmonized information among riverine countries; (2) promote consultation at all levels, especially within pertinent international institutions and mechanisms; (3) and define medium-range priority action programs of common interest to improve water management and decrease pollution. In the 2000
Ministerial Declaration on Water Security in the 21st Century, the environmental ministers from several countries met and set out a declaration on water needs in the new millennium: (1) to meet the needs of people who lack access to safe water and sanitation, (2) to secure the water supply for food, (3) to protect ecosystems with sustainable water resources, (4) to share water resources among bordering countries including the correct governing of water, (5) to value water, and (6) to manage future risks regarding water
(World Water Forum 2000). Technology has also been developed to conserve water through drip irrigation and low flow toilets. In theory, farmers can change irrigation practices and each of us can change our daily domestic water needs, but the technology is often too expensive or otherwise not available for those who need it most.

Changing Climate and Deterioration of Environmental Health

2011-04-24T09:59:00.000-07:00

Climate change refers to any significant change in measures of climate. Potential effects of this climate change are likely to include more variable weather, stronger and longer heat waves, more frequent heavy precipitation events, more frequent and severe droughts, extreme weather events such as flooding and tropical cyclones, rises in sea level, and increased air pollution. Other effects may result from ecosystem shifting and disruption.

Climate change is an emerging risk factor for human health. According to Third Assessment Report, the IPCC summarized to state: “Climate change can affect human health directly (e.g., impacts of thermal stress, death/injury in floods and storms) and indirectly through changes in the ranges of disease vectors, water-borne pathogens, water quality, air quality, and food availability and quality. The actual health impacts will be strongly influenced by local environmental conditions and socio-economic circumstances, and by the range of social, institutional, technological, and behavioral adaptations taken to reduce the full range of threats to health.”
Broadly, a change in climatic conditions can have three kinds of health impacts:

· Those that are relatively direct, usually caused by weather extremes.

· The health consequences of various processes of environmental change and ecological disruption that occur in response to climate change.

· The diverse health consequences – traumatic, infectious, nutritional, psychological and other – that occur in demoralized and displaced populations in the wake of climate-induced economic dislocation, environmental decline, and conflict situations.

Climatic changes over recent decades have probably already affected some health outcomes. Indeed, the World Health Organization estimated, in its "World Health Report 2002", that climate change was estimated to be responsible in 2000 for approximately 2.4% of worldwide diarrhoea, and 6% of malaria in some middle-income countries.

Marked short-term fluctuations in weather can cause acute adverse health effects:

· Extremes of both heat and cold can cause potentially fatal illnesses, e.g. heat stress or hypothermia, as well as increasing death rates from heart and respiratory diseases.

· In cities, stagnant weather conditions can trap both warm air and air pollutants -- leading to smog episodes with significant health impacts.

· These effects can be significant. Abnormally high temperatures in Europe in the summer of 2003 were associated with at least 27,000 more deaths than the equivalent period in previous years.

Other weather extremes, such as heavy rains, floods, and hurricanes, also have severe impacts on health. Approximately 600,000 deaths occurred world-wide as a result of weather-related natural disasters in the 1990s; and some 95% of these were in poor countries.

To large extent, a changing climate is likely to affect public health which depends on safe drinking water, sufficient food, secure shelter, and good social conditions. Reviews of the likely impacts of climate change by the IPCC suggest that a warming climate is likely to bring some localized benefits but overall, however, the health effects of a rapidly changing climate are likely to be overwhelmingly negative, particularly in the poorest communities, which have contributed least to greenhouse gas emissions. Some of the health effects include:

· Increasing frequencies of heat waves: recent analyses show that human-induced climate change significantly increased the likelihood of the European summer heat wave of 2003.

· More variable precipitation patterns are likely to compromise the supply of freshwater, increasing risks of water-borne disease.

· Rising temperatures and variable precipitation are likely to decrease the production of staple foods in many of the poorest regions, increasing risks of malnutrition.

· Rising sea levels increase the risk of coastal flooding, and may necessitate population displacement. More than half of the world's population now lives within 60km of the sea. Some of the most vulnerable regions are the Nile delta in Egypt, the Ganges-Brahmaputra delta in Bangladesh, and many small islands, such as the Maldives.

· Changes in climate are likely to lengthen the transmission seasons of important vector-borne diseases, and to alter their geographic range, potentially bringing them to regions which lack either population immunity or a strong public health infrastructure.

Heat exposure has a range of health effects, from mild heat rashes to deadly heat stroke. Heat exposure can also worsen several chronic diseases, including cardiovascular and respiratory disease. The results can be severe and result in both increased illness and death. Heat also increases ground-level ozone concentrations, causing direct lung injury and increasing the severity of respiratory diseases such as asthma and chronic obstructive pulmonary disease.

The direct effects of extreme weather events include drowning from floods, injuries from floods, and structural collapse. Indirect effects outnumber the direct effects and likely will be more costly. Potential indirect effects include aggravation of chronic diseases due to interruptions in health care service, significant mental health concerns both from interrupted care and geographic displacement, and socioeconomic disruption resulting from population displacement and infrastructure loss.

Many of unanticipated ecosystem effects could have indirect health effects. Increased concentrations of ground-level carbon dioxide and longer growing seasons could result in higher pollen production, worsening allergic and respiratory disease. Increased carbon dioxide concentrations in sea water may cause oceans to grow more acidic and is likely to contribute to adverse ecosystem changes in the world’s tropical oceans. This would have potentially dramatic implications for fisheries and the food supply in certain regions of the world. Major regional ecosystem stresses may result in mass population movement and conflict, with significant health effects.

Air quality is highly affected by weather and climate conditions. In turn, certain aspects of air quality are known to affect health. Ozone causes direct, reversible lung injury; increases premature mortality; worsens respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD); and may cause chronic lung damage.

Storms and extreme precipitation events have several direct health effects. They are associated with flooding, which can immediately cause injury and death, followed by a spike in traumatic injury and carbon monoxide poisoning during redevelopment and rebuilding efforts when the events are severe enough to prompt evacuation and resettlement. Storms resulting in evacuation are also associated with increased risk for gastrointestinal illness among evacuees. Extreme precipitation events are also associated with outbreaks of gastrointestinal disease. Heat waves are already the most deadly weather-related exposure in the U.S. Studies suggest that, if current emissions hold steady, excess heat-related deaths in the U.S. could go up from an average of about 700 each year currently, to between 3,000 and 5,000 per year by 2050.

Climate is one of many variables known to affect the rates of vector-borne and zoonotic diseases. Of particular importance are vector mosquito species, which spread malaria and viral diseases such as dengue and yellow fever. Malaria, today, is mostly confined to tropical and subtropical regions. The disease’s sensitivity to climate is illustrated by desert and highland border areas where higher temperatures and rainfall associated with El Niño may increase transmission of malaria. Dengue is the most important arboviral disease of humans particularly in urban settings. Between 1970 and 1995, the annual number of dengue epidemics in the South Pacific was positively correlated with La Niña conditions (i.e., warmer and wetter). In the tropics diarrhoeal diseases typically peak during the rainy season. Both floods and droughts increase the risk of diarrhoeal diseases. Major causes of diarrhoea linked to heavy rainfall and contaminated water supplies are: cholera, cryptosporidium, E.coliinfection, giardia, shigella, typhoid, and viruses such as hepatitis A.

Various analyses have shown that health impacts are often the largest single contributor to the costs of environmental damages. The Govt. health authorities should undertake a comprehensive evaluation of the possible health implications of such changes and need to determine priorities for planning and decision-making. The health sector should be involved jointly with agricultural, meteorological, environmental, and planning agencies to ensure that health considerations are given adequate weight.

But not only for these, individual awareness is also needed such as lifestyle change, behavioral change, efficient use of energy etc.

Consequences of Deprivation of Safe Water and Sanitation

2011-04-24T09:51:00.000-07:00

People need clean water and sanitation to sustain their health and maintain their dignity. Water also sustains ecological systems and provides an input into the production systems that maintain livelihoods. Water pervades all aspects of human development and human freedom. Water security is an integral part of this broader conception of human security. In broad terms water security is about ensuring that every person has reliable access to enough safe water at an affordable price to lead a healthy, dignified and productive life, while maintaining the ecological systems that provide water and also depend on water. When these conditions are not met, or when access to water is disrupted, people face acute human security risks transmitted through poor health and the disruption of livelihoods and vulnerability. Clean water and sanitation are among the most powerful drivers for human development. They extend opportunity, enhance dignity and help create a virtuous cycle of improving health and rising wealth. Some 2.6 billion people— half the developing world’s population— do not have access to basic sanitation. And systemic data underreporting means that these figures understate the problem. “Not having access” to water and sanitation is a polite euphemism for a form of deprivation that threatens life, destroys opportunity and undermines human dignity.

Deprivation in water and sanitation produces multiplier effects. The ledger includes the following costs for human development:

1. Some 1.8 million child deaths each year as a result of diarrhoea—4,900 deaths each day or an under-five population equivalent in size to that for London and New York combined. Diarrhoea, estimated to be responsible for 12 % of the child deaths under five years of age in developing countries. Deaths from diarrhoea in 2004 were some six times greater than the average annual deaths in armed conflict for the 1990s. Together, unclean water and poor sanitation is the world’s second biggest killer of children.

2. The loss of 443 million school days each year from water-related illness.

3. Close to half of all people in developing countries suffering at any given time from a health problem caused by water and sanitation deficits.

4. Millions of women spending several hours a day collecting water.

5. Lifecycles of disadvantage affecting millions of people, with illness and lost educational opportunities in childhood leading to poverty in adulthood.

Every year, unsafe water, coupled with a lack of basic sanitation, kills at least 1.6 million children under the age of five years and more than eight times the number of people who died in the Asian tsunami of 2004. At the beginning of the Water for Life decade, 1.1 billion people did not have access to an improved source of drinking water, 84% of the population without access to an improved source of drinking water live in rural areas. 2.6 billion people, more than 40% of the world population, do not use a toilet, but defecate in the open or in unsanitary places. In 2004, more than three out of every five rural people, over 2 billion, did not have access to a basic sanitation facility. If the current trend persists, nearly 1.7 billion rural dwellers will still not have access to improved sanitation by 2015.

Bangladesh has a population of about 144 million in an area of 147,570 square kilometers with as many as 1,800 people living per square kilometer. Forty per cent of the population lives under the poverty line. An estimate puts the total population at 181 million by 2025 with 41% living in the urban areas - nearly half of them will be poor without services. In Bangladesh up to 40% of overall morbidity is due to water and sanitation related disease in some communities. In the year 2000, 12.1% DALYS were lost due to Diarrhoeal disease and 90% of these were attributable to environmental causes of which 65% could be averted through improvements in water supply, environmental sanitation (latrines, drainage, rubbish disposal) and hygiene awareness. Diarrhoeal diseases account for 11% of total deaths in Bangladesh due to Water pollution, unsafe drinking water and Lack of hygiene and poor sanitation. According to WHO, 1998 They account for the high infant mortality rates - 15% of U5MR. The most alarming and interesting fact is Hygiene related disease costs the country, Tk 5 billion (£30million) per year for treatment alone. According to the Dhaka Water and Sewerage Authorities, the ground water table -- the source of drinking water for one third of this city's 10 million people -- has become contaminated with harmful bacteria.

Bangladesh is grappling with the largest mass poisoning of a population in history because groundwater used for drinking has been contaminated with naturally occurring inorganic arsenic. It is estimated that of the 125 million inhabitants of Bangladesh between 35 million and 77 million are at risk of drinking contaminated water The scale of this environmental disaster is greater than any seen before; it is beyond the accidents at Bhopal, India, in 1984, and Chernobyl, Ukraine, in 1986.

Arsenic in groundwater poses a great challenge to the water supply in the country. Since the detection of arsenic in 1993, various organisations have been screening tube wells for arsenic contamination in excess of the Bangladesh Drinking Water Standard (BDWS) of 0.05mg/L. The most contaminated areas lie in the southern region, in the districts of Chandpur, Comilla, Noakhali, Munshiganj, Faridpur, Madaripur, Gopalganj, Shariatpur and Satkhira. Excessive levels have also been found in the South West and part of the North West, North East and North Central regions. Arsenic-contaminated drinking-water: a public health emergency. Exposure to arsenic from drinking water increases the risk of skin, lung and bladder cancer and possibly that of other sites also. In a report WHO has predicted that in most of the southern part of Bangladesh almost 1 in every 10 adult deaths will be a result of cancer triggered by Arsenic poisoning in the next decade (Contamination of drinking-water by arsenic in Bangladesh: a public health emergency -Alan H. Smith, Elena O. Lingas & Mahfuzar Rahman). From the experience of Taiwan it has been forecasted that almost two million of people are at risk of developing cancer in the next decades. Large numbers of cancers are predicted to occur in the future, including fatal internal cancers. The cause is known: each day of continued exposure increases the risk of morbidity and death Sustained drinking of water containing 500 mg/l of arsenic may result in 1 in 10 people dying from arsenic-related cancers. Unlike other major health problems experienced in Bangladesh, arsenic-caused diseases can be eradicated at relatively low cost.

Safe water and sanitation is primary factors for every aspects of successfulness of society. So it’s very much important to concern about these unless country will give value not only for present but also for future generation.

Tourism, Transport and Environmental Pollution

2011-04-24T08:49:00.000-07:00

Tourism is travel for predominantly recreational or leisure purposes. According to the definition of The World Tourism Organisation tourists are people who "travel to and stay in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes not related to the exercise of an activity remunerated from within the place visited." In context of globalisation international tourism is the largest and most rapidly expanding industry in the world. Many of the most popular tourist destinations depend heavily on the natural environment for their appeal. According to the World Tourism Organisation, 698 million people travelled to a foreign country in 2000, spending more US $ 478 billion. International tourism receipts combined with passenger transport currently total more than US $ 575 billion – making tourism the world's number one export earner.

Tourism involves the movement of people from their homes to other destinations and accounts for about 50 per cent of traffic movements; to give an indication, the ICAO reported that the number of international air passengers worldwide rose from 88 million in 1972 to 344 million in 1994. From 594 million international travellers in 1996, numbers leaped to 698 million international travellers in 2000, numbers are forecast to leap to 1,018 million by 2010 and 1.6 billion by 2020. One consequence of this increase in air transport is that tourism now accounts for more than 60 per cent of air travel and is therefore responsible for an important share of air emissions and the role of air travel within the industry is also likely to expand and cause considerable environmental damage and to have knock-on effects on the tourism industry itself. Air pollution from tourist transportation has impacts on the global level, especially from carbon dioxide (CO2) emissions related to transportation energy use.

And it can contribute to severe local air pollution. Some of these impacts are quite specific to tourist activities. Currently, aircraft account for around three per cent of all emissions globally.
The International Panel on Climate Change expects this to increase by up to seven per cent by 2050. Because emissions from other sectors are also expected to increase, this figure masks the increase in real terms: the actual tonnage of carbon emitted, driven by air traffic increase of five per cent per year, will increase by over 75 per cent by 2015.

Tourism is thus a significant contributor to the increasing concentrations of greenhouse gases in the atmosphere. This rapidly expanding air traffic contributes about 2.5 per cent of the production of CO2. One study estimated that a single transatlantic return flight emits almost half the CO2 emissions produced by all other sources (lighting, heating, car use, etcetera) consumed by an average person yearly and air transport has been estimated to be between two and four times more polluting per passenger carried than road transport.

According to Tourism Concern, scientists predict that by 2015 half of the annual destruction of the ozone layer will be caused by air travel. It is known that road transport also contributes to green house gases during tourism activities through World Tourism Organisation. In France, for example domestic and international tourism now account for seven to eight per cent of France's total road transport emissions (which themselves were the origin of 39 per cent of the country's total CO2 emissions in 1990, up from eight per cent 30 years earlier). Noise pollution from airplanes, cars, and buses as well as recreational vehicles such as snowmobiles and jet skis, is an ever-growing problem of modern life. In addition to causing annoyance, stress, and even hearing loss for it humans, it causes distress to wildlife, especially in sensitive areas. For instance, noise generated by snowmobiles can cause animals to alter their natural activity patterns. From case study in winter 2000, 76,271 people entered Yellowstone National Park on snowmobiles, outnumbering the 40,727 visitors who came in cars, 10,779 in snow coaches and 512 on skis.

A survey of snowmobile impacts on natural sounds at Yellowstone found that snowmobile noise could be heard 70 percent of the time at 11 of 13 sample sites, and 90 per cent of the time at eight sites. At the Old Faithful geyser, snowmobiles could be heard 100 per cent of the time during the daytime period studied. Snowmobile noise drowned out even the sound of the geyser erupting. Transport, which is at the heart of travel and tourism is an evident challenge - not only the high profile air transport with its direct interrelationship to greenhouse gases, but also road and rail transport which are major factors in intraregional and domestic tourism. Recently UNWTO and WWF have taken some policies and initiatives about transport pollution. Let us hope for the best outcome from these actions, otherwise tourism will face dangerous impacts. In Bangladesh though tourism is not a broad trade, from now onwards we need to be concerned to protect the environment first.

The Responsibilities of Tourist to Protect Environment

2011-04-24T08:25:00.000-07:00

Nature provides the conditions for a healthy, secure and fulfilling existence. Among the many benefits people receive from nature are fresh water, food, protection, and spiritual enrichment that means it provides the whole life system upon which our well-being and economics depends. The potential impact of climate change on ecosystem diversity is overshadowed by the Overwhelming effect of human-induced modifications.
Now the business of tourism and environmental diversity is interrelated. Tourism forms the backbone of the economy in many local communities worldwide and but today, the observed impacts of climate changes are becoming increasingly and rapidly obvious and many tourism site are affected because of the form of changing seasons, abnormal weather, beach erosion, higher sea levels, greater damage from sea surges and storms, heat waves and reduced water supply, droughts, floods, marked changes in the behaviour of animals and plants and as well as impact of customs & cultures.

Currently, the global rate of extinction is at least 100 times the natural rate, and an estimated 34,000 plant and 5,200 animal species face extinction. One in eight of all birds species, one quarter of all mammals and one third of all amphibians are endangered. This is not only the alarming news but also a concerning matter of every people. So every tourist as well as involved of tourism should knowledge of this change and have concerned that healthy and sound ecosystem are our best defense against the impact of this change.
As a traveler or tourist or visitor, you can show great awarenesses for Environment like that….

Before going the site that you visit, must well informed and learn about the culture and customs of the areas.

Don’t disturb Environment and respect to nature. Always follow the rules and discipline when you hike. Do not remove plants or feed animals, and never litter and never destroy the habitat. At the sea do not take any corals, shells, dried fish, starfish, sea-fans and other marine souvenirs - removal can seriously disrupt ecosystems. Navigation in reef water needs special care - do not anchor on reefs which can be easily damaged.

The tourist and visitor always noticed about the protected area. Get any necessary permits before visiting nature reserves or other protected areas. Leave these areas as you found them and do not disturb the wildlife there. It is also noted that visitor demand and tourist expenditures support existing protected areas and can lead to the protection of additional nature

View and photograph wildlife from a distance and remember that in the optimal wildlife viewing experience, the animal never knew you were there. Suppress the natural temptation to move too close and respect signs of distress such as alarm calls, distraction displays, laid-back ears, and raised hair.

Honor to local culture, traditions and religious places. Uncivil and insensitive behaviour such as taking photographs of people and historical structure without permission, shouting or failure to observe local customs, can cause offence. So never do any moral crime. Note that being nude or semi-nude in public is unacceptable and illegal in some countries (e.g. Islamic countries).

The 1st International Conference on Climate Change and Tourism, Convened and organized by the World Tourism Organization heard evidence that tourists' water consumption was far in excess of that of local residents and that much of the resulting water stress arises in regions and areas which already suffer from inherent water shortages. So every tourist should use water economically.

Conscious about the limited use of energy during traveling. Use of air conditioning and hot water as your need. Turn off all lights and taps when you leave hotel rooms.

Many personal products deteriorate the indoor quality as well as also outdoor when it doesn’t keep right place. Minimize your use of personal care products (i.e.; bleach) and detergents to wash linen, and reuse your hotel towels and bed-linen. Dispose of sanitary waste properly. Don't flush cotton buds, condoms, tampons and plastics down the toilet - or you might just find them on the beach next time you visit.

Reduce the impact of your recreational activities by avoiding sports which have a significant harmful impact on the environment or choose more progressive establishments (e.g. golf courses which recycle water).

Resources are limited, so return the newspapers, magazines and your beverage containers for refunds and for recycled and reduce the number of bags, napkins and disposable cups you use when you eat fast food.

Choose lodgings that have effective waste treatment systems, that recycle, that are energy efficient, and, where possible, that use environmentally friendly energy sources such as solar energy or hydroelectric power.

Don’t do such activities which break the rules and regulations like light fires, hard drinks, play songs loudly. It disturbs the nature and surrounding environment. So pay attention to signals and behave responsibly.

You can spend your vacation in your country which helps your country self reliant but when journey for holiday destination by aero plane you are contributing to significant emissions of carbon dioxide causing climate change. For example, air travel is the fastest growing source of greenhouse gas emissions and therefore increases the risk of continued global warming. Currently, aircraft account for around 3% of all emissions globally. The International Panel on Climate Change expects this to increase by up to 7% by 2050. Because emissions from other sectors are also expected to increase, this figure masks the increase in real terms: the actual tonnage of carbon emitted, driven by air traffic increase of 5% per year, will increase by over 75% by 2015. Concomitantly, from 698 million international travelers in 2000, numbers are forecast to leap to 1,018 million by 2010 and 1.6 billion by 2020. As a consequence, the role of air travel within the tourism industry is likely to expand, cause considerable environmental damage, and to have knock-on effects on the tourism industry itself. If you have to fly, consider buying carbon offsets to compensate for the emissions caused by your flight.

The 1st International Conference on Climate Change and Tourism, Convened and organized by the World Tourism Organization also clearly felt that the tourism industry shares some of the responsibility for road transport pollution. When you travel by any by route or water route transport, use train, bus or boat where many seats are allowed to seat on because single transport like microbus, private car contain less number passenger and use same fuel as use as bus or same types of big vehicles. This is called passenger efficiency of vehicles. So save fuel and save the Environment.

The entire tourism sites rely on a mixture of natural beauty, good weather and safe conditions to attract holiday-makers.

Climate change undoubtedly affects many destinations negatively. But we have to also concern that Tourism is not just a potential victim of climate change it is also contributes to its causes. Everybody is interested in economic development, but somehow we have to strike the balance between this development and the preservation of nature. So every tourist, traveler and authorities of tourism should aware of this change and respect to the whole Environment.

Human Interference and Species Extinction

2011-04-24T07:59:00.000-07:00

Biodiversity is a term applied to describe the complexity of life. It is generally measured at three levels: the variety of species; the genetic diversity found within members of the same species (what makes you different from your neighbour); and the diversity of the ecosystems within which species live. These three levels are intimately connected. Genetic diversity is essential to the prosperity of the species, giving it the resources to adapt. And the number of species within an ecosystem is closely tied to the health and size of the ecosystem itself.
However it is defined, biodiversity is the stuff of life. However far we may be removed from "wild" biodiversity in our daily lives, it remains the source of our food and most of our medicines. In addition, 15 percent of our energy is derived from burning plant materials. Even in the United States, wild species contribute around 4.5 percent of GDP. Due to agricultural modernisation, changes in diets and population density, humankind increasingly depends on a reduced amount of agricultural biological diversity for its food supplies.

A dozen species of animals provide 90% of the animal protein consumed globally and just four crop species provide half of plant-based calories in the human diet. FAO estimates that about three-quarters of the genetic diversity found in agricultural crops have been lost over the last century. Of 6, 300 animal breeds, 1,350 are endangered or already extinct. This rapidly diminishing gene pool is cause for concern.
Nobody knows how many species there are in the world -- or how fast they are disappearing. Fewer than 2 million have been catalogued and estimates of the total vary wildly, ranging from 7 million to as many as 80 million. The currently accepted working estimate is 13.6 million.
At least 40 per cent of the world's economy and 80 per cent of the needs of the poor are derived from biological resources. In addition, the richer the diversity of life, the greater the opportunity for medical discoveries, economic development, and adaptive responses to such new challenges as climate change.

Biodiversity is an immense resource, built up over 3.5 billion years of evolution. It embraces not only the number of species on Earth, but the range of habitats and genetic diversity within species as well. It is of enormous importance to humans. Of the 270,000 known plants, some 3,000 are exploited for food, and between 25,000 and 50,000 more are used in traditional medicine. Wild plants are potential sources of new medicines and of material for genetic engineering. Biodiversity is a major attraction for tourism, and not least a lasting source of human aesthetic pleasure.
Around 1.75 million species have been scientifically described. More than half of these are insects, while vertebrates -- including fish, birds, mammals, reptiles and amphibians -- make up only 2.5 percent. But the real number is certainly far higher. Most recent estimates fall in the 7 to 20 million ranges, though a widely acceptable working estimate, used by the United Nations Environment Programme's Global Biodiversity Assessment of 1995, is 13.6 million.

Most ecologists believe that we are currently undergoing a mass extinction driven by human activities. Since 1600, 484 animal and 654 plant species are known to have become extinct through human actions. But these are only the tip of a vast iceberg. Since most species are as yet undescribed, the majority of current extinctions are going unrecorded -- species are dying out before we even learn of their existence. Projections of future losses vary widely, from 2 to 25 percent of all species over the next 25 years. But even the low end of this range is 1,000 times the background rate of extinction.

The total extinction of a species is drastic and at present irreversible. But local extinctions are serious, and far more common. Data on species are far from complete, but countries and taxonomic groups with more complete information have a higher share of species threatened, so it is quite likely that as more data become available, the percentage judged to be under threat will rise. The prospects for the coming decades look gloomy. Forests are the home of between 50 and 90 percent of all land species in the world. If tropical deforestation continues at present rate for the next 30 years, it is estimated that 5 to 11 percent of forest species will eventually be lost.

Wildlife habitat is becoming increasingly fragmented by human activities -- making way for cities, farms and roads. Fragmentation lowers the size of individual populations, reducing their genetic variability, and making them more vulnerable to extinction. Human barriers also make it difficult for animals and plants to migrate in response to environmental change.
At the same time, global warming will be shifting present temperature zones generally polewards and uphill. Species will have a greater need to migrate but will encounter human barriers blocking their way. Some species which prefer cold temperatures will see their natural habitats disappear completely. Meanwhile genetic engineering -- unless it is rigorously controlled -- may introduce new genes which could spread to wildlife with unforeseeable consequences. There is no doubt that genes from existing commercial crops can pass to wild relatives, and even with rigorous control measures, it is unlikely that accidental transfers could be prevented indefinitely. The extent to which this is likely to have negative impacts on the environment and biological diversity is still not known.

The Global Biodiversity Assessment found that the major threat to biodiversity was habitat loss, fragmentation and degradation, due to the need for land for farms, dwellings, industry, services, transport and leisure. Of those species that are threatened, habitat loss affects 44 percent of the bird species, 55 percent of the fishes, 68 percent of the reptiles, and 75 percent of the mammals. Other direct pressures are overexploitation of species for commercial gain, for subsistence or for sport. The introduction of alien species, pollution and climate change are all major threats. Population is a major indirect cause underlying most of these threats.
Population density is closely linked with most forms of habitat loss. A sample of 50 non-desert countries in Asia and Africa where wildlife habitat loss has been estimated showed that the percentage loss tends to be highest where population density is highest. The top 20 percent of countries, ranked in terms of habitat loss, had lost an average of 85 percent of their original wildlife habitat. Their average population density was 189 people per square kilometer. The 20 percent with lowest population density had lost an average of only 41 percent of their wildlife habitat -- and their average population density was only 29 people per square kilometer.

Governments are gradually moving to give wider areas protected status, but progress is slow. Globally, in 1997, only 6.4 percent of the land area was protected. To protect the full range of species, large areas are needed, but 88 percent of protected areas in 1997 were smaller than 100,000 hectares -- a square with sides of about 32 kilometers.

Biodiversity is integral part of our life as different aspects of our activities. For our survival, we must be aware about biodiversity and take measures to check its the mass extinction. It is high time for sustainable use and conservation of biodiversity otherwise our own extinction will also come soon.

Foreboding of an Environmental Disaster

2011-04-24T07:52:00.000-07:00

HUMAN population growth is the primary threat to the world's environment. Each person requires energy, space and resources to survive, resulting in environmental losses. Our population is rapidly rising beyond the earth's ability to regenerate and sustain us with a reasonable quality of life. We are exceeding the carrying capacity of our planet, challenging the existence of several species, including our own.

When people think of human impacts on the environment, they often think in terms of total population and population growth. The scale of our activities depends on population, consumption and the resource or pollution impact of technologies; all three of these factors are steadily increasing.

Urbanisation
Rapid urban growth can bring environmental problems for cities. With many cities growing at 4 to 5% a year, provision of clean water, sewage, electricity and roads can rarely keep up with population growth. Lack of sewage treatment leads to water pollution, eutrophication and biodiversity loss in rivers and around outlets. Water demand may lower river and groundwater levels. The International Decade for Drinking Water Supply and Sanitation (1980-90) documented the growth of those without clean water in urban Africa, rising from 28 million to 31 million; those without safe sanitation rose from 38 million to 47 million.

We have transformed half the world's land for our own uses -- around 11% each for farming and forestry, 26% for pasture, and another 2 to 3% for housing, industry, services and transport. In most parts of the world, cultivated land has not expanded in line with population growth, decreasing the amount of farmland per person. The area per person has declined slowly in developed countries, from 0.65 hectares in 1965, to 0.51 hectares 30 years later. In developing countries, where population growth is faster, the area per person fell from 0.3 to 0.19 hectares over this same period.

Freshwater
Freshwater is crucial for survival, health, agriculture, industry, comfort and leisure. But freshwater sources are limited -- there is only so much to go around: the larger the population, the less there is for each person.

In 1995, some 436 million people were already suffering water scarcity or stress, causing severe development problems. There are conflicts among farmers and between rural and urban needs, and heightening tensions between countries dependent on the same resources, such as with India and Bangladesh.

The UN's 1996 population projection has estimated that, by 2050, the projected number of people suffering water stress or scarcity will have risen to 4 billion approximately.

Biodiversity
Most ecologists believe that human activities are causing mass extinction. Since 1600, 484 animal and 654 plant species are known to have become extinct through human actions. The total extinction of a species is drastic and irreversible, but local extinction is also serious, and far more common. The Global Biodiversity Assessment listed the major threats to biodiversity as habitat loss, fragmentation and degradation, due to the need for land for farms, dwellings, industry, services, transport and leisure. Of those species that are threatened, habitat loss affects 44% of bird species, 55% of fishes, 68% of reptiles, and 75% of mammals.

Population density is closely linked with most forms of habitat loss. A sample of non-desert countries where wildlife habitat loss has been estimated showed that the percentage loss tends to be highest where population density is highest. The top 20% of countries, ranked in terms of habitat loss, had lost an average of 85% of the original wildlife habitat. Their average population density was 189 people per square kilometre. The 20%, with lowest population density, had lost an average of 41% of their wildlife habitat -- and their average population density was only 29 people per square kilometre.

Forests
We lose forests at the rate of 112 million hectares each decade, an area twice the size of Kenya or France. Highly populated countries such as India and China have almost come to the end of their period of deforestation and have begun to reverse forest loss. Some of the fastest rates of deforestation are found in middle-income developing countries with strong commercial logging interests (Indonesia 2.4%, the Philippines 3.5%, and Thailand 2.6%).

A number of studies have found a strong correlation between population density and deforestation rates on national levels. A recent report by the United Nations Population Fund estimated an average loss of 1.8% of forests per year between 1980-90, where the population density was 89 people per square kilometre. Areas with slower deforestation tend to have lower population density; where there are just 34 people per square kilometre, the deforestation rate was only 0.5%.

Coastal environment
High percentages of human population and activity are located on or near coasts. Coastal areas have always been important for trade, transport and defence, containing some of the densest concentrations of human population and activities today. Nearly two-fifths of the world's populations live within 150 kilometres of a coastline. A recent assessment found that over half the world's coastlines are at risk from coastal development, with over one- third at high risk. Nearly three quarters of the world's marine protected areas are similarly threatened. In addition, human activities over vast inland areas impact coasts and coastal waters. Much of the water pollution and sediment eroded from whole watersheds is transported to the sea.

Mangroves
Mangroves cover an estimated 18 million hectares of the earth's tropical coastlines, around one quarter of the total. Mangroves host unique species, and are important nurseries for commercial marine species.

It is estimated that around half of all tropical mangroves have been destroyed. The Philippines, Puerto Rico, Kenya and Liberia have lost over 70%. Major pressures are cutting for fuel wood and timber; habitat conversion for coastal development or aquaculture (often shrimp farming); and damming of rivers which alters water salinity. Other direct and indirect causes of these pressures include: population growth, tourism and resource consumption in and around coastal areas.

Coral reefs
The world has an estimated 255, 000 square kilometres of near-surface coral reefs, constituting one of the richest resources of biodiversity on the planet. A recent study estimated that 58% of the world's reefs are threatened by human activity, almost half of these seriously so. In Southeast Asia, which has very high levels of coral and fish diversity, more than 80% are potentially at risk.

The threats to coral reefs are many: over-fishing, pushing fish stocks below their maximum sustainable yield; destructive fishing practices; and extraction. Water pollution from industry, sewage, fertiliser, and sediment eroded from deforested or badly farmed areas, all wash into the sea, reducing light levels and physically smothering corals.

Marine environment
Oceans make up seven-tenths of the planet's surface, and we use an estimated 8% of their total primary productivity. Yet we have fished up to the limits or beyond, altering the ecology of a vast range of marine species.

Assessments from 1999 found that 44% of major fish stocks have already been exploited to their maximum sustainable yield. Another 16% are over-fished, meaning future catches will fall unless remedial action is taken.

Pollution from oil spillages, runoff and rivers includes sewage, industrial effluents, fertilisers, pesticides and herbicides. Air pollution is the source of one-third of marine pollutants.

There are now around 50 known "dead zones" with no or low oxygen. Most of these have appeared over the last half-century, and are blamed on excessive influx of nitrogen and phosphorus from farming and sewage. The dead zone in the Gulf of Mexico is 4,144 square kilometres, doubling in size since 1993.

We need to voluntarily limit our growth, and promote contraceptive use, before nature controls our population for us with famines, droughts and plagues. Our children's future depends on us.

How people preserve or abuse the environment largely determines whether living standards improve or deteriorate. Population growth, urban expansion, and resource exploitation do not bode well for the future. Without practicing sustainable development, humanity faces a deteriorating environment and may even invite ecological disaster.

Urban Biodiversity: An Essence for City Dwellers

2011-04-24T07:41:00.000-07:00

"Millions of people are feeling lonely together" -Ponting 1990

Cities are growing rapidly, in 50 years more than 80% of the world's population will live in an urban environment. Urban green areas e.g. parks and gardens, woodlands and forests with socio-cultural values are important for urban life. Moving in search of a better life, people across the globe have abandoned traditional socio-economic systems, broken ecological bonds with nature, and flocked to urban centers. While this process started in the "northern" or "developed" world, less developed countries have quickly caught up.

Sustainable urban development requires providing a healthy and sustainable living environment with basic services for all. A healthy and multifunctional urban green structure is one of the basic services to provide. Urban and peri-urban forestry (UPF), focusing on the tree-dominated part of urban and periurban green space, is a strategic, integrative, interdisciplinary, and participatory approach. Its goal is to sustainably develop the multiple benefits of forests and trees in urban environments.

Ongoing urbanization has brought about a wide range of challenges across the globe, and not only in terms of population growth. In the United States, for example, metropolitan areas tripled in size between 1950 and 1990. More land is needed for urban areas to provide inputs and outputs of resources and energy, with a detrimental effect on forests and other green areas. During the early 1990s, more than a quarter of green spaces in Asia were expected to be lost within two decades due to continued urbanization and suburbanization.

Continuing urbanization in the developing world has led to major problems in terms of hunger, poverty, inadequate shelter, social segregation, unemployment, pollution of water, soil, and atmosphere; and so onward.

Experiences and research during recent years have shown that urban green structures are more than just "icing on the cake."

The thought of urban forestry is new in Dhaka. As a developing country, city authorities are busy most of the time to give service facilities to the people rather than think about green resources.

Most of the time different green institutions in the city and government deal with big urban greening programme by tree plantation activities. There are no exact areas wise statistics for the percentage of trees in the city and also no area wise planning for tree plantation.

In 2002 Dhaka City Corporation (DCC) were able to plant only 29 thousand trees out of the targeted 45 thousand because of lack of empty space. In 2003, DCC has planned to plant six thousand trees to replace those that have been uprooted, and a further ten thousand in whatever empty space is available in Uttara and Mirpur area of Dhaka. But adequate open spaces are needed for the sustainable development of a city.

Let's discuss why we really need urban biodiversity in term of social, economic and environmental context.

Nursery activity is an important entrepreneurial outlet for the poor people. 78% of nursery owners indicated that the management of their nursery is their only employment.

The average daily sales of the nurseries surveyed exceeded USD 130, the biggest and most successful one third of nurseries, however, have average daily sales in excess of USD 190.

Considering among data it can be assume that most of the beneficiary of this industry are low income groups of the urban area .If this industry will explore rapidly, more poor people will get benefit from that sector.

In Dhaka studies shown that suspended particulate matter (SPM) and ambient sulphur dioxide levels of air pollution are about 4 times and 5 times higher than the levels prescribed in Bangladesh Air Quality Standard. An ADB report shown that 3,850 premature deaths could be avoided had there been a reduction of SPM concentrations in Dhaka to the level of Bangladesh Air Quality Standard. Economic cost, because of such deaths and illnesses in Bangladesh, may reach US $800 Million a year. One of the most effective ways to control air pollution is creating more woodland around the city and increasing the number of trees in the parks and street in Dhaka. The SPM can be captured by the leaves of evergreen tree species .Several research in US revealed that trees can remove pollution by intercepting airborne particles. In 1994, trees in New York City removed an estimated 1,821 metric tons of air pollution at an estimated value to society of $ 9.5 million. Another study found that woodland in Nottingham was estimated to reduce concentrations of sulphur dioxide and nitrogen oxides in the air by 4-5%.It is also well known that all vegetation absorb carbon dioxide and release oxygen, do purifying the air.

It found that in Dhaka 33% inhabitants experience hearing problems from noise pollution. But increasing trees and other vegetation can play an important role in attenuating noise through and absorbing sound energy. In US one research estimate suggested that 7db noise reduction was achieved for every 33m of forest whish other reported field tests show apparent loudness reduced by 50% by wide belts of trees and soft ground.

According to Dhaka city structure plan 1995-2015 policy 10 &11 demands the augmenting of city open space and securing the future open space although there have no specific policy which can support sustainable livelihood.

Well-planned and well managed green areas are essential for environmental and high quality of life for Dhaka city dwellers. So it is very much for RAJUK and Dhaka City Corporation to rethink about these issues and necessary actions need to be taken.

Climate Change and Neglected Tropical Disease An Overlooked issue

2011-04-24T07:32:00.000-07:00

Climate change is increasingly being implicated in species' range shifts throughout the world, including those of important vector and reservoir species for infectious diseases. Intergovernmental Panel on Climate Change predicted that the mean global temperature would increase by between 1.4°C and 5.8°C over the period 1990 to 2100. Recent investigations attribute more than 150,000 deaths per year and a global disease burden of approximately 5 million DALYs annually to climate change. It is well known that the impact of climate change is on physical and biological systems, including human health. An area that has received particular attention is the potential impact of global warming on shifts in the spatio-temporal distribution of disease vectors, and hence the frequency and transmission dynamics of vector-borne diseases. Vectors, pathogens (parasites), and hosts survive and reproduce within certain optimal climatic conditions. Changes in climate will alter the transmission of vector-borne diseases in different ways, such as changing the survival and reproduction rate of the vector and of the pathogen (parasite), as well as changing vector activities.
Public health officials often use the term tropical diseases to refer collectively to a list of infectious diseases that are found primarily in developing countries. These include malaria, schistosomiasis, dengue, trypanosomiasis, leprosy, cholera, and leishmaniasis, among others. Many of these diseases are spread by insect vectors, and all of them disproportionately affect the world's poor. Malaria is the most severe of these as stated by World Health Organization, but other diseases, less well known and sometimes described as neglected and also imposes grave burdens on people living in the tropics. The World Health Organization estimates that neglected tropical diseases affect over one billion people each year and cause about 570,000 deaths annually. For example, some 200 million people are currently infected with schistosomiasis, a parasite that is transmitted through poor sanitation. Perhaps 50 million cases of dengue occur each year, of which 500,000 lead to devastating hemorrhagic fever, with 22,000 resulting deaths. More than 1.5 billion of the world's poorest people are affected by a range of bacterial and worm based diseases including trachoma, river blindness and lymphatic filariasis. They are just some of so-called neglected tropical diseases, which are diseases of poverty. But despite the numbers they affect, and their health and social consequences, these diseases attract less than one per cent of the total health funding for the developing world.

The potential impact of global warming on the transmission of the neglected tropical diseases has received insufficient attention from researchers and different organization. Most studies on the impact of global warming on the transmission of tropical diseases have focused on malaria but very few studies have been carried out regarding the neglected tropical diseases. The Intergovernmental Panel on Climate Change (IPCC) has specially investigated the changing burdens of infectious disease that may result from climate change. One IPCC background report notes that: Climate plays a dominant role in determining the distribution and abundance of insects and tick species directly, through its effects on vector and parasite development, and indirectly through its effects on host plants and animals and land-use changes. Therefore, it is anticipated that climate change will have an effect on the geographical range and seasonal activity of vector species and, potentially, disease transmission.

Global attention to infectious disease is primarily focused on HIV/AIDS, tuberculosis and malaria; the big three, as they are called, were responsible for over five million deaths in 2007 and are responsible for 39% of all deaths attributed to infectious disease. Unfortunately, this attention has not extended to a group of parasitic and microbial diseases called the neglected tropical diseases (NTDs). These diseases are largely overlooked, due to their low mortality rate and the poverty of their sufferers. Neglected tropical diseases affect the poorest individuals. Over 70% of the affected areas have low to lower-middle income economies. They thrive under poor sanitary conditions, where clean water and food are unavailable and where insect vectors are abundant. Women, children and those geographically isolated from health care are particularly susceptible. Those in conflict-ridden areas are also particularly susceptible, due to the disruption of any health-care infrastructure. Aside from thriving in poverty, the NTDs are also said to be poverty-promoting conditions, as they reduce worker productivity and impair childhood development, and, consequently, the future earning abilities of those children. The resulting economic loss tends to worsen already impoverished conditions.

Bangladesh is highly vulnerable to climate change and its high population density. Floods and cyclones are some of the major challenges that the country faces resulting in the greatest economic and human losses to the country. Higher temperatures including more extreme weather events and sea level rise are already evident in Bangladesh. One estimate is that the average increase in temperature in Bangladesh would be 1.3ºC and 2.6ºC by the year 2030 and 2075 respectively with respect to the base year 1990. Global warming will increase the intensity of southwest monsoon, which will, in turn, bring about catastrophic ravages like floods and have far reaching consequences on health. During and after floods, the water borne diseases increase due to heavy contamination of the surface water. Thus climate change could cause floods, break-down of sanitation system, and more water and food-borne diseases like soil-transmitted helminthiasis (STH), cholera, and other diarrhoeal diseases. Bangladesh may be one of the worst hit countries of the world due to a predicted rise in sea level. The increase in salinity in underground water will affect the availability of fresh safe water. As a result, people will be more inclined to use unsafe, contaminated surface water and will contact various water borne infectious diseases like cholera and other diarrhoeal diseases and STH. Incidence of vector-borne diseases like malaria, filaria, leishmania and dengue are likely to increase as a result climate change in this region. This may increase the human contact with the vectors responsible for spread of diseases like malaria, filaria, leishmania and dengue. Though the surveillance system is very weak with gross under reporting, 13 districts of Bangladesh are known to be endemic for malaria, 34 for filariasis and 45 for visceral leishmaniasis (VL). Dengue has been detected in all six divisional headquarters of Bangladesh whereas STH affects our population throughout the country. Filariasis is a parasitic disease which is believed to have infected about 20 million people; 10 million are with various forms of disability, leaving another 70 million at risk of infection. The incidence of visceral leishmaniasis on the other hand is estimated to be about 12,000 per year with about 65 million people at risk of contracting the disease. Some reports claimed a death rate of more than 10% in patients suffering from VL. About 70000 to 80000 malaria cases and 300 to 700 death cases are reported yearly.

The impact of climate changes on neglected tropical diseases is itself neglected. There is an urgent need for researchers and organizations to investigate further the potential impact of climate changes on the transmission of neglected tropical diseases. The findings of such research are required so that populations might be able to adapt or, if necessary, migrate to overcome increased risks for transmission of neglected tropical diseases caused by climate changes.