Pagelet ID: 836 
Major Threats   
Category: NHW Home > Wetlands
 
Description:

Invasive species

Wattle, Ulux spp., Cytissus spp., Lantana camara is widespread at all sites. Invasive were found growing on the edges of the swamps forming potentially harmful threats to the health of wetland systems.

Exotics

Eucalyptus species were found in upland regions along most of the protected wetlands. Visually, there seemed to be a lot of water around the trees. The trees were always found planted at the higher lands and near the source points.

Pesticide inflow

Most vegetable growers are located in valleys close to wetlands. In most cases, there appears to be unrestricted access for water and no controls on the inputs of agriculture. As per our interviews and data collection, chemical runoff is very high.

Usage of wetland resources is taken to points of breakdown, with tea plantations being raised till the edge of the wetland and in areas like Gudalur, tea was being raised on top of wetlands. In spite of knowing from experience, that tea will not do well in these regions; farmers act in ignorance and contribute towards deterioration of these precious resources. The issue raised by farmers is “why leave the land fallow? This answer is difficult to answer but the team clearly understood that most of the surveyed wetlands have a high probability of contaminated water through chemical inflows.

Effects of Pollution

Pesticide pollution of wetlands reduces the "crop" of aquatic insects essential for the growth and development of aquatic birds. The use of pesticides on farmland has further reduced the amount of safe habitat available for birds that already have to make do with small woodlots, hedgerows, shelterbelts, and farm ponds for nesting or feeding. Habitats bordering agricultural fields can become a liability if birds are attracted into the fields and then inadvertently poisoned by toxic insecticides. Herbicide use, in plantations, may cause ground-dwelling birds to lose the leafy shelters that protect them against predators and bad weather. The potential for the herbicide spray to drift through the air and contaminate distant wetlands through water runoff is also a concern. In Nilgiris, we already see a trend where rampant usage of pesticides has led to decreased biodiversity in these places. Though, scientific evidence is lacking, yet estimations and interviews with local people who complain about the loss of biodiversity have led us to believe that pesticides do play a major role in accentuating loss in biodiversity.

Grazing

Many of the wetlands we surveyed were subjected to high levels of grazing but whether this was a pressure or a part of the ecosystem one needs to look into. Review of existing knowledge base suggests that grazing plays a positive and detrimental role in the wetland ecosystem. Local people have in fact been traditionally nurturing wetlands for the express reason of providing fodder for their cattle. Yet, as we observed in a number of places, pressure from cattle has increased manifold times and a large number of wetlands are shrinking in their biodiversity levels. Grazing stunts growth of vulnerable plants and wildlifeis forced to compete with cattle for the limited amount of fodder available. Utilization of wetlands as grazing lands, if properly managed, proves to be a source of valuable nutrients for cattle. More villages and local people must come forward and learn from the best practices of grazing from communities that have successfully managed grazing for a long time.

 
Location : Globe
 
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NHW Home > Wetlands
 
Posted by  keystone Updated:   2007-03-07 08:47:02.0
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