How long we can survive?
Ecosystem ranges between a community of microbes in a water drop to the entire Himalayan ecosystem. Natural ecosystem constitutes the foundation of human well-being .Ecosystem services are the benefits we get from ecosystems. Various levels (genes, species, landscape, and ecosystems) and aspects of biodiversity contribute to ecosystem services. The basic materials needed for human survival and quality life are provided through four ecosystem services. Out of them, provisioning services include food and water, timber, and fodder. Regulating services, including regulation of climate, flood, waste, disease, and maintenance of water quality determine the distribution of provisioning – , and cultural -services like spiritual and aesthetic values. Regulating services depend on functional diversity within ecosystem. Alteration of ecosystems and exploitation of natural resources results in short- term substantial gains for human well-being and economic development. However, biodiversity loss, ecosystem degradation, and subsequent changes in ecosystem services lead to a decrease in human well-being in long term by exacerbating poverty, and increasing inequities.
Natural or anthropogenic causes which change ecosystem is known as driver. A direct driver changes ecosystem process, while an indirect one alters direct drivers. Change and overexploitation of habitat, introduction of invasive species, and increasing pollution are important to mention. Function of biodiversity in ecosystems is complex. Ecosystem services are influenced by the existing species and their functional traits. Higher genetic and species diversity make ecosystems more resistant and resilient to disturbance. In such situation, ecosystems function and provide critical services, such as water purification. As biodiversity declines, system resilience also diminishes. Low resilience ecosystems when face disturbance reach a threshold at which abrupt change occurs. Ecosystems govern the biogeochemical and biophysical processes that regulate the earth system.Interconnection among biodiversity, ecosystems, human livelihoods, and climate system can address many burning issues of the present human civilization. Ecosystem complexity and functioning govern species coexistence. Loss of key species, such as top predators, seed dispersers, and pollinators disrupt ecosystem functioning. Climate change provides an excellent example of human activities on natural systems and human wellbeing. Ecosystem’s function includes microbial regulation of nutrients, behavioral mechanisms, and predator-prey interactions. Cultural services are recognized as key determinants of human well-being, including maintenance of cultural traditions, identity, and spirituality. Functioning ecosystems serve as crucial buffers against extreme climate events, act as carbon sinks, and filters for water- and air-borne pollutants. In coastal areas, mangroves and other wetlands are effective in providing shoreline stability, reducing erosion, trapping sediments, toxins and nutrients. Forests, shrub grasslands, freshwater, and coastal ecosystems provide vital sources of food, and complementary source of income.
The Millennium Ecosystem Assessment(MA) after examining the state of 24 services concluded that 15 of 24 services are in decline, including provision of fresh water, marine fisheries production, number and quality of places of spiritual and religious value, ability of atmosphere to cleanse itself, and capacity of agro-ecosystem to provide pest control .A team of leading scientists categorized ecosystem services into 17 major groups and concluded that ecosystem services provide an important portion of total contribution to human welfare. The MA define driver as any natural or human- induced factor that directly or indirectly causes a change in an ecosystem .
Global driving forces are demographic, economic, sociopolitical, cultural and religious, scientific and technological, and physical and biological. All drivers other than physical and biological are considered indirect. Important direct drivers include changes in climate, plant nutrient use, land conversion, and diseases and invasive species .Sociopolitical drivers are fundamental of human influence on environment. Human conflicts act both as a direct and indirect driver of change in ecosystem services. Total species richness only partially captures ecosystem services, in which all services are weighted equally. However, ongoing and in many cases accelerating decline and losses in biodiversity over the past two decades have decreased the capacity of many ecosystems, to provide services and have negative impacts on sustainable development. Ecosystem degradation particularly affects the poor, who are directly dependent on ecosystem services at local level. Human well-being and poverty are intrinsically linked on a continuum. The gap between rich and poor is becoming become greater. About 60% of the world’s poor live in areas of low agricultural potential, which may be equated to ecological vulnerability. Poor farmers, fisherman, nomads, and other users extract materials from the environment to support livelihoods.
Developing countries are plagued with social inequalities along with their defining features like poverty, inadequate social amenities, and high rate of unemployment. Of the assessed ecosystem services, about 60% are degraded including fisheries, waste treatment and detoxification, water purification, natural hazard protection, regulation of air quality and regional or local climate, and erosion control. Most have been directly affected by increasing demand for specific provisioning services like fisheries, meat, water, timber, fibre and fuel .It is recorded that 37 countries are ecosystem deficit countries with high level of human development and excessive impacts on global environment. Twenty seven countries are human deficit countries, which put low pressures on ecosystems, but have poor level of human development. A total of 116 countries are double deficit countries and combine weak environmental performance with inadequate human development. Eighteen countries are extreme double deficit countries with poor or bad Human Well-being Index (HWI) and Economic Well-being Index (EWI) scores. Of these countries, eight countries are located in Asia, 4 in central and East Asia, 2 each in northern Africa and West Africa. In fact, no country is sustainable or even close to sustainability. We have to prepare for the impacts that are inevitable over forthcoming decades. Reducing the vulnerability of human populations, and ecosystems that are at risk is a must.
Quality of life of minority of affluent people has improved, although such improvement is not at all satisfactory among the majority of the world’s population. For example, in 1997, 14% of world population went hungry everyday as reported elsewhere. High poverty level in more than one billion people, with an income of less than $ 1 per day is a matter of serious concern. Biodiversity loss causes a deterioration of ecosystem services, and increases the likelihood of negative impacts on human well-being.
Of the 260 million people that live below the poverty line in India, more than 100 million are reported to be partially or wholly dependent on forests for survival. Extensive deforestation has reduced forest cover to about a fifth of the geographical area. Shifting cultivation, extraction of forest produce, and hunting are the chief local usages. Forests are threatened due to construction of dams and reservoirs, timber harvesting, and illegal trade. Forests are interrupted by agro-ecosystems, and urban settlements. Grasslands are also degrading. High grazing pressure, reclamation for agriculture and tree plantation, introduction and spread of exotic species, and fire pose risks to grasslands. Changes in land use affect desert ecosystems adversely. Expansion of agriculture came mostly at expense of the forests, but also took its toll on grasslands, wetlands, and coastal belts. Legislation now protects the boundaries of forests, but habitats such as scrub land, grasslands, deserts, wetlands, and mangroves remain vulnerable in various parts of the country. Practice of agriculture, horticulture, farm forestry, acquaculture, and fishing use scarce land, water, and bioresources wastefully. Over-application of nitrogenous fertilizer continues unchecked. Pesticides pose a serious risk to human health and biodiversity. A total of 28% of India’s population lived in cities by 2001. Urban lifestyles consume a huge amount of water, energy and raw materials. Various industries including iron and steel, thermal power plants, cement, oil refinery, petrochemical, pesticide, and fertilizer present a substantial risk to air and water quality. Tourism industry also aids a different type of risk to fragile ecosystem. Irrigation canal has completely changed the land use and habitat in northwestern extremity of Thar Desert. Dams, industrial and sewage effluent, pollutants from agriculture, and siltation adversely affect wetlands. Local use of mangroves includes removal of fuel wood, timber, medicinal plants, fodder, hides, honey and wax. Commercial fishing is common and extraction of mollusc’s shell is known in some parts. Coral reefs are susceptible to destructive fishing practices. All the above-said environmental problems need immediate amelioration for sustaining our survival as well as survival of our future generations.
About the Author
Qualification: M. Sc;Ph. D.
Publication: Three books and 20research and 40 popular articles
Experience: About 25 years of writing
7 Wonders of India: Pichavaram Mangrove Forests