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Ecosystem Manhandled
The
future of Earth is uncertain because of the activities of its inhabitants.
There is no dearth of warning signals — loss of plants and animals,
changing climate, depleting groundwater level and unpredictable ocean
currents — and from scientists and conservationists. The quicker we
understand the consequences of these changes, the better.
Among other things, the longer summers, and the delay and change in
rainfall patterns leave no doubt that the Earth’s climate is gradually
changing. Earth’s climate and biosphere are influenced by the increasing
concentrations of certain gases that have the potential to transform
significantly the planet’s heat and radiation balance. Among these are
carbon-dioxide, methane and nitrous oxide, and some trace gases in the
atmosphere. Such alteration of Earth’s heat and radiation balance is
leading to a warmer climate, a process that may quicken in the next
century. The point of concern is that this change in climate will have a
serious impact on all life forms on land and the aquatic biosphere,
including human civilisation.
Historically, the invaluable life support systems of Earth have largely
been ignored till it came under severe threat. For example, deforestation
has only now underscored the critical role forests play in regulating the
water cycle — in particular, in mitigating floods, droughts, the erosive
forces of wind and rain, and silting of dams and irrigation
canals/channels. Today, the escalating impact of human activity on
forests, wetlands, and other ecosystems imperil the delivery of such
services. The primary threat is posed by land-use changes that result in a
loss in biodiversity as well as disruption of carbon, nitrogen, and other
bio-geochemical cycles; by human-caused invasions of exotic species; by
the release of toxic substances; and by the depletion of the stratospheric
ozone.
There is no alternative to society having a clear idea of its dependence,
or impact, on Earth’s natural resources.
The Consequences
The scientific assessments of the utilisation pattern of these resources
and its consequences on the various ecosystems must be understood. We must
know how the loss of 30-50 per cent of Earth’s species will affect the
world’s economic growth and the health of humans? Why is there a rise in
Earth’s average surface temperature and how has it started affecting the
global climate? What is the nature of the negative impact of the increase
of different harmful gases in the atmosphere? How has the loss of wetlands
affected the lives of millions of poor people? What are the consequences
of over-exploitation of the world’s major freshwater and marine fisheries?
How is soil-erosion related to food insecurity?
The average adult breathes more than 3,000 gallons of air daily. The
global vehicle population is more than 730 million, which is increasing
everyday and their emissions poison the atmosphere. Increasing air
pollution is not only harming human health but also damaging various
ecosystems and their functions.
Although energy is central to modern human existence, the negative impact
of its production, distribution and use has grown exponentially. Using
fossil fuels depletes a non-renewable source of energy and emits air
pollutants, and processing those fuels produces greenhouse gases,
including carbon-dioxide. World carbon-dioxide emissions are projected to
rise approximately 50 per cent to 37.1 billion tonnes by 2025, with large
increases expected from developing nations such as China and India.
Water is an important component of Earth and life is totally dependant on
it. Although water covers 70 per cent of the planet’s surface, only 2.5
per cent is freshwater, and of this only about one per cent suitable for
human use. We are polluting our freshwater systems faster than ever
before. The growing human population is depleting groundwater faster than
it can be replenished.
According to a 2005 report by the Millennium Ecosystem Assessment, a
United Nations-associated programme, the ecosystems have changed more
quickly and extensively in the past 50 years than in any other period.
Natural ecosystems perform fundamental life-support services without which
human civilisations would cease to thrive. These eco-systems services are
being provided to us free of cost and include purification of air and
water, detoxification and decomposition of wastes, regulation of climate,
regeneration of soil fertility, and production and maintenance of
biodiversity, from which key ingredients of our agricultural,
pharmaceutical, and industrial enterprises are derived.
Economic Impact
Biodiversity is important to the global economy as it contributes greatly
to pharmaceutical industries, agriculture, horticulture, fisheries and
nature tourism. Similarly, biodiversity is essential for ensuring food
security of the planet’s growing population. Plant-breeding using wild
genetic stock is responsible for high agriculture yields in many developed
and developing nations.
However, the Millennium Ecosystems Assessment states that about 60 per
cent of the world’s ecosystems are being degraded. Industrial activity
affects ecosystems through pollution emissions, waste discharges and
consumption of natural resources such as trees. Other reports reveal that
human activity has damaged more than half the world’s coastal ecosystems,
and about 230 million acres of forestland have been lost during the past
decade.
More than 11,000 species are listed as endangered. We are endangering our
own future by degrading the environment and over-exploiting the natural
resources.
Humanity came into being after most ecosystem services were available for
hundreds of millions of years. These services are so fundamental to life
that they are easy to take for granted, and they are so large in scale
that it is hard to imagine that human activity can irreparably disrupt
them.
Scientists are indicating the ramifications of climatic change and the
loss of natural resources. There is no choice before planners and
policy-makers but to act expeditiously.
It is a matter of urgency that appropriate policies and action plans are
framed and implemented, both at the national and international levels, for
a more secure future of all species, including man.
Vinod Kumar Yadav
The author, based in Kolkata, is a member
of the Indian Forest Service
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