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4. STATEMENT OF PROBLEMS RELATING TO BIODIVERSITY 4.1 Root causes for the loss
of biodiversity Biodiversity is not evenly distributed around the world. The single most obvious pattern in the global distribution of species is the overall increase in species richness as latitude decreases toward the equator. Biodiversity of any area is particularly relevant to food production, which can be considered in terms of the quality of wild foods gathered and trapped, hunted or fished, as well as the range of crop and stock varieties bred and maintained to support livelihoods. Genetic biodiversity is also crucial in conferring resilience on crops and stock for farmers who cannot afford to buy pesticides, fertilizers and other inputs. The intrinsic worth of biodiversity is enough for some people to leave it untouched and to recognize its existence value. But this is not happening, and serious threats have come in to the biodiversity. The root causes for the losses of biodiversity may be direct or indirect. Some of them in the context of Pondicherry are discussed below : 4.2 Loss of genetic diversity In Pondicherry, the direct cause of genetic erosion is due to spread of modern, commercial agriculture, which includes conversion to monocultures. The introduction of new crop varieties has led to replacement and loss of traditional crop varieties developed by the subsistence farmers for their high variability. In Pondicherry at least few rice varieties have become extinct in the past two decades or, not cultivated because of its low yield potentials. Similarly several breeds of livestock should also have become extinct or threatened. This indicates that the genetic base on which production systems rely is being eroded through loss of local varieties of crops and breeds of livestock. Records of other causes of genetic erosion include destruction of
even little forest and bush lands. Linked with these losses, loss of
vital knowledge about how different varieties and breeds were produced
and when best flourish. Even more genetic material is lost when species
go extinct. The major loss is due to human-induced mass extinctions. Habitat loss is held to be the main direct cause of species loss.
Degradation of habitats
through unsustainable harvesting of plants and animals have been
noted. For example, because of high trade demand is commercial
exploitation of several trees, many tree species are declining due to
unsustainable felling. Alien species are cited as the most common cause
of mammal extinctions, accounting to 40% of disappearance where the
cause of extinction has been determined. (Groombridge, 1992) Ecosystems and habitats can be lost entirely, degraded or fragmented of proper care is not taken immediately. The most common cause of terrestrial wild land ecosystem loss is its conversion to farming, urban development and infrastructure, and over-exploitation of ecosystem resources, Natural disasters such as floods and fires, also do great damage to biodiversity. Other than the direct root causes for the loss of biodiversity as mentioned above, we have certain underlying factors also provide conditions for the loss of biodiversity. These are general ones but they can be applied to Pondicherry region also. These factors are interrelated, and have indirect variable impacts. (Wood et al 2000). Population growth, distribution and migration patterns are significant factors in the degradation of environment and loss of biodiversity. Right now there are two billion people in the world and the number grows by 1.4 per cent per year. Mass movement and migration can damage biodiversity. Poverty and inequality are other root causes for loss of
biodiversity. Poor and weak mostly migrate to marginal lands where
conversion to agriculture results in loss of biodiversity. Non
participatory management of natural resources have been very damaging to
biodiversity. National policies including macro-economic policies and trade
practices have resulted in constant loss of biodiversity for various
reasons. For example, subsidies have resulted in unsustainable
development. Environment laws are weak or not enforced. Environmental
impact studies have not been carried out
and Government agencies with responsibility for environment and
natural resources management are under- staffed and under-resourced. Ultimately biodiversity
management is hindered by lack of knowledge and ignorance of how human
use and management systems affect different ecosystems. Lack
of awareness
and pre-sights
and callous
attitude towards
nature as
well as
lack of
criteria for
economic evolution
of bio-resources
constitute the
core from
which many
negative impacts
on biodiversity
conservation emerge. It is, therefore,
important to identify the
factors affecting the biodiversity
and then
to suggest
the solutions. 4.3 Agriculture Ever
since the
year 1958–59
the area
put under
plough in Pondicherry has
been gradually decreasing
while the
area sown
more than
once has
been steadily on
the increase
over a
period of
preceding two
decades and
then started
declining or stabilizing
in comparison
with the
net area
cultivated. With
the increase
in the intensity of
cropping, there
has been
continuous depletion
of soil
resources, particularly, the major
plant nutrients
as well
as micro-nutrients.
To replenish
these nutrient
resources, huge
quantities of
chemical fertilizers
are applied
to the
soil continuously for years
together, thereby
changing the
soil reaction
constantly in
terms of
soil pH,
which is
one of the
reasons for
inhibiting the
survival of
the micro-flora
and micro-fauna
of the soil. It is observed that there has been a drastic reduction in the area irrigated by surface water resources and there has been a corresponding increase in the area irrigated by ground water sources through the net work of bore wells. Consequently, large quantities of solvable salts including toxic substances like sulphides and iron compounds are increasingly brought about and deposited on the soil surface which are also responsible for inhibiting the growth of micro organisms to a larger extent. Normally fallowing of cultivable lands for a specific length of period is a desirable agronomic practice to enable the soil to replenish its wear and tear and to recoup the plant nutrient resources for supporting the crop growth in the succeeding years. The statistics reveal that even though that the current fallows, other fallows and culturable waste are gradually increasing year after year, there is no restoration of cultivable land. It reveals the fact that these fallowing lands are nothing but unauthorized conversion of land use from agriculture to non agriculture uses like housing etc., which have become irreversible and it is quite obvious that the fallowing lands in the Union Territory is not being for the purpose of leaving any period of rest to the lands and the associated micro- organism but only for other reasons and such of those lands on which cultivation is being practiced are continuously put under stress and strain without any gap. 4.3.1 Over exploitation of ground water resources Due to neglect of maintenance of irrigation tanks in Pondicherry region the entire burden of irrigation of all crops fell on ground water resources. Apart from this the requirement of drinking water and industries are also met from the ground water resources. The net result is depletion of ground water resources and decline of water table in the coastal aquifers and salinization of aquifers due to salt water intrusion. The water table has declined by 5 to 23 meters from the east to the north west of Pondicherry region between 1981 and 2001. There is a telling effect on agriculture biodiversity due to over-exploitation of water resources and the damage caused to the coastal aquifers is irreversible. If the trend continues, the agriculture activities within Pondicherry region will be seriously affected with salt water intrusion and probably no irrigated crops could be grown with ground water in future. Around 84 irrigation tanks are expected to be rehabilitated by the end of December 2004, under Tank Rehabilitation Project (The European Union aided Project), which would be able to irrigate 6000 Ha at least for one crop. Apart from this, there would be enhanced recharge of the ground water aquifers by not using the tube wells and from the return flows of the irrigated fields under the tank command areas. In order to conserve the ground water resources, field schools are conducted in the villages in participatory mode in crop water management and thereby awareness is created among the farmers to use water for irrigation of crops judiciously. 4.3.2 Excessive use of pesticides After
the introduction
of high
yielding varieties
from 1960s, the
need for
applying external
inputs like
chemical fertilizers
and usages
of pesticides
for control
of pest
and diseases
to get
better productive
in rice
crop was
inevitable. Extensive
cultivation of
paddy crop was
undertaken in the
Union Territory of Pondicherry
for the
past 25
years. Single
crop had
become as
double crop
and triple
crop in
this region and a
stage has
come now where
plateuing yields
in rice
crop. Extensive damage done to the micro-environment of the agriculture fields by destroying predators, while controlling pest and diseases, caused total imbalance of various organisms in the field of agriculture biodiversity. To tackle the above said issues, the Dept. of Agriculture has conducted a detailed soil survey in the Union Territory of Pondicherry and the same has been documented. A detailed study of the status of micronutrients available in the soils of Pondicherry region was conducted and documented. Inputs like green manure seeds, biofertilizer and enriched compost, neem cake and micronutrients are made available to the farmers at 75% and 50% subsidized cost. Integrated Pest Management practices are strongly advised to the farmers. Non availability of adequate quantity of the raw material like garbage for the preparation of enriched compost and the inputs like green manure seeds for timely distribution to the farmers, is the major gap which is inhibiting the desired level of achievement. 4.4 Marine animals diversity Pondicherry has a significant long coastline. Issues pertaining to conservation of marine life (marine animals and plants) need to be identified and a conservation strategy developed. In fact extremely little data is available in this regard as far as Pondicherry is concerned. Beach
erosion is
also one
of the threats to
nesting habitats
of the
turtles along the
Pondicherry coast.
Because of
the shore
erosion the
slope of
the beach has
become a
hindrance for
the upward
movement of
the turtle from
the high
tide water
mark. Beach
erosion was
intensive along
the beaches
of Moorthikuppam
and between
Kanagachettykulam and
Kalapet villages. Fearing the possible loss of buildings due to erosion led the use of many methods to stabilize beaches. Along the Pondicherry coast, Government has erosion preventive embankments by piling large stones all along the coast from the new harbour area to Vaithikuppam which makes the nesting habitat unavailable to the turtles. One of the major threats to the turtle nesting habitat is the violation of the Environmental Conservation Act which prohibits the construction / establishment of any sort of buildings on the shore with in 500 m. From the high tide water mark. But contrastingly in earlier time, most of the buildings were constructed on the shore. In certain places most of the houses and beach resorts are located with in 100 - 300 m. from the seashore. The other threats identified are disturbances and predators. Now a days, the sea shore is always bustling with the activities by fishermen throughout night due to different methods of fishing which they adopt, such as “crab fishing” by burning torches out of burning cycle tyres and also by the internal conflict and disturbance between the neighboring groups of the near by fishing villages, which is a common feature, due to some reason or other, at present. The beaching of the “Catamarans” all along the beaches near their settlements which completely occupies the nestling areas available to the turtles. Artificial lights and the menace of the feral dogs have been an perennial threat to the nesting turtles. 4.5 Animal husbandry Union
Territory of Pondicherry does not have its own native breed of
livestock. Most of them are from the neighbouring state of Tamilnadu. The loss
of domesticated animals which are better adopted to local stress
conditions is mainly due the policy of introduction of white revolution
and produce more milk and eggs / meat
and other animal products resulting in wide scale hybridization. 4.6 Town & country planning Increase in population due to
heavy impact of economic activity due to various tax concession
has resulted in the conversion of prime
agriculture land into housing, industrial and business structures. It
has also put pressure on all the scarce natural resources including
water. Increased human activities resulted into increased pollution and
loss of biodiversity for various reasons. 4.7 Pollution Unplanned development of Pondicherry has created serious environmental problems, leading to lowering of living standards. Scarcities of basic requirements like drinking water, proper drainage facilities for waste water, inadequate sewage treatment and disposal facility has put Union Territory of Pondicherry environmentally in tight spot. 4.7.1
Consequences of Open drainage The pathogens that gain entrance into bodies of water arrive
there via intestinal discharges. Further more Escherichia
coli and related organisms designated as coliforms, fecal
streptococci and Clostridium perfringens are normal
inhabitants of
the large intestine of the man and other animals. Thus the
presence of any of these bacterial species in water is evidence of
excreta of fecal pollution of human or animal origin.
Sewage containing human excreta, however is the most dangerous
material that pollutes the water, people with communicable disease of
many eliminate, the causative organisms in their excreta. The most
important microbial, communicable diseases transmitted through polluted
water are typhoid, paratyphoid, amoebic dysentery, bacillary dysentery,
cholera and infective hepatitis. In Pondicherry, the quality of waste water in grand canal, upper
canal mixes with sea, the
dissolved oxygen content is found to be nil in both upper & grand
canal water, whereas in the mixing point D.O value is 5.8 mg/l it may be
due to wave motion and improper mixing. In the sewage sea and river
mixing point the total coliform count is 475 and the faecal coliform
count is 130
which is not
satisfactory. Faecal
coliform is one of the indicators of faecal contamination and disease
risk. This situation could
be attributed mainly to the
untreated sewage. In
all the, three places, the oil and grease contents are observed to be
above the standard values and in
upper canal it is found to be very high. 4.7.2 Effect of drain clossing and overflow During monsoon season, the clogging and overflow of drains is observed in Pondicherry, not only during monsoon, but also, now and then drains get clogged and cause overflow. This is because of the dumping of garbage, plastics etc. into the gutter. The clogging of drain leads to foul smell and also provides conditions inevitable for breeding of vectors. Because of this condition, many diseases like malaria, filaria, dengue fever, viral fever, brain fever are reported. 4.7.3 Vehicular
pollution Normal
air pollution caused due to vehicular movement on the road leads to
generation of dust including suspended particulate matter
(SPM) from the roads and emission of gaseous pollutants such as
SO2, NOx, CO and Pb from the exhaust of the vehicles. Apart from this, pollution also results due to spillage of
diesel, petrol, lubricants, etc. on the roads. Ambient air quality was
monitored in eight locations in the city for suspended particulate
matter (SPM), SO2, NOx, and lead. During day time (10 hours
to 18 hours) 8 hourly monitoring was conducted Near Old Bus Stand, Near
Patel Petrol Bunk, Near Vasanthi Petrol Bunk, Near Swedeshi cotton Mill,
East coast road – Kalapet, Indira Gandhi Statue, Ashram Petrol Bunk,
Indira Nagar, Gorimedu. SPM was found to be
high Near Old Bus stand (960lg/m3)
Indira Nagar
Gorimedu (443.8lg/m3) Patel
Petrol Bunk (381lg/m3)
Near Swadeshi Cotton Mills (368lg/m3),
Indira Gandhi Statue (209lg/m3)
and Ashram Petrol Bunk (204.3lg/m3).
Thus from the 8 locations surveyed, in 6 places the SPM exceeding the
standard limits. This is mainly due to the heavy vehicular movement in
these areas. The SPM value in Vasanthi Petrol Bunk (77lg/m3) and East Coast Road, Kalapet (166lg/m3)
was recorded below the specified standard limit of 200lg/m3.
In the town due to the more frequency of the vehicular movement
SPM has been more when
compared to the East Coast Road. The increased level of SPM is due to
the vehicular exhaust, i.e. incomplete combustion of fuel, unburnt
hydrocarbon and due to vehicular movement dust blown up from the
roadside. 4.7.4 Respirable particulate matter Ambient air quality monitoring was conducted to find out the respirable particulate matter in the ambient air, in the following four locations; Near Indira Gandhi Statue, Near Muruga theatre signal, Near Raja theatre signal and Near New Bus stand. The SO2 and NOx were also monitored in the four locations. The respirable particulate matter and total suspended particulate matter is found to be above the standard limit, this is mainly due to the more number of automobiles plying in these areas near Indira Gandhi Statue, Near Muruga theatre signal, Near Raja theatre signal and Near New Bus stand. However, the SO2 and NOx values are found to be within the standard limits in these areas. The SO2 concentration in ambient air was found to be satisfactory in all the 8 monitored locations well within the stipulated standards limits. The oxides of nitrogen concentration were found to be slightly higher in the two locations. East Coast Road Kalapet the NOx concentration is 86.33 lg/m3 and the location of Ashram Petrol Bunk was 82.53lg/m3. |