Department of Zoology, B.N Mandal University, Madhepura, Bihar, India
Received : 22nd January, 2020 ; Revised : 27th February, 2020
Abstract: Portfolio function of any biotic population in an ecosystem has multidimensional control & is primarily engineered by S-W diversity index of the species. S-W diversity index is popular statistical information index as quantitative tool to quantify the species abundance, richness & bifold product value of any species that yields significant result for understanding their asset & liability value in the portfolio of biotic community. It further helps in contemplating the strategies for the management & development of sustainable environment & ecosystem. Fresh water crabs being the members of crustacean arthropods have distinct role in the wetland habitats where they successfully dwell, propagate & contribute in the portfolio of the community. Crabs sampled from the Kanwar lake of Begusarai were taxonomically identified as nine different species like–Barytelphusa cunicularis, Barytelphusa guerini, Barytelphusa lugubris, Inglethelphusa fronto, Paratelphusa masoniona, Paratelphusa spinigera, Potamon lugubre, Sartoriana spinigera & Vanni travancorica. Random sampling data of these nine species in terms of their per unit net sweep numerical count were recorded as species abundance (pi)- an important asset of the wetland community portfolio accommodating these crabs. When the data were subjected to S-W diversity index tool on the basis of the species abundance, the value of H (H= –ߑpi x log pi) for all the species of crabs present in the sixty random sampling sites was found in the range of 0.8301- 0.8927 during different seasons which indicate that they have profitable asset investment contribution (PF index ranging between 6.523-10.081) as edible as well as other beneficial resource in the community as per portfolio function laws.