Ecology,habitat and bird community structure at Oussudu lake: towards a strategy for conservation and management

• 1. Oussudu lake is a large, shallow wetland situated close to the city of Pondicherry, India. The lake harbours rich flora and fauna, and has been recognized as one of the important wetlands of Asia by the International Union for Conservation of Nature and Natural Resources (IUCN).
• 2. This paper summarizes the results of a 5‐year study on the annual composition, richness, diversity and population density of the bird community at Oussudu. A GIS database was developed on the basis of field surveys and allied studies.
• 3. The study reveals a declining trend in the number and diversity of the birds found at Oussudu with the exception of herons, egrets, plovers and lapwings. A relationship appears to exist between this decline in bird diversity and an increase in illegal fishing, cattle grazing, encroachments and pollution. These factors may have contributed to the decline of food and shelter for the birds.
• 4. A strategy has been developed for the conservation and management of the Oussudu catchment which would help in reversing undesirable trends.

Copyright © 2003 John Wiley & Sons, Ltd.     

EVALUATING POTASSIUM-USE-EFFICIENT COTTON GENOTYPES USING DIFFERENT RANKING METHODS

Identification of cotton (Gossypium hirsutum L.) genotypes efficient in potassium (K) uptake and utilization, under K-deficient conditions represents a cost-effective and environmentally friendly approach for low-K-input agriculture. It would reduce the costly input of K-fertilizers and manage K resources in agro-ecosystems. We ranked 25 cotton genotypes for their K use efficiency under deficient and adequate K regimes in hydroponics, using two different methods. K deficiency generally reduced cotton growth; however, K-efficient genotypes accumulated more biomass due to higher K uptake. Genotype NIBGE-2 exhibited excellent adaptation potential in terms of high shoot dry weight under both K regimes and ranked as the only most desirable, “efficient-responsive” genotype. Genotype CIM-506 produced low shoot dry weight under low K condition and ranked as “non-efficient.” Genotype Desi okra produced low shoot dry weight at adequate K level and ranked as “non-responsive.” Genotype ranking using two different methods ensured the validity of results.