author(s)
Raj Priyanka Rathor, ML Ojha, VP Saini and NR Keer

abstract
A five micro-water sheds of Banswara district of Southern Rajasthan were chosen to evaluate the biotic conditions and growth performance of Indian major carps. Water quality parameters viz., water temperature (30.4-32.7 áµ’C), pH (8.2-9.3), dissolved oxygen (7.05-10.10mg/l), free CO₂(0-0.45mg/l), total dissolved solids (145.7-212mg/l), electrical conductivity (303-339mS/cm), total hardness (114-175mg/l), total alkalinity (98-141mg/l), Nitrate-Nitrogen (0.122-0.247mg/l), Gross primary productivity (0.138-0.528gC/m³/h), Net primary productivity (0.034-0.166gC/m³/h) and Community respiration (0.044-0.248gC/m³/h) were observed throughout the study period and indicate that the water of the selected micro-watersheds remained congenial for growth of fish except very high pH in a few water bodies. The phytoplankton counts in different micro-watersheds were ranged between 145 to 225 nos/l. Whereas, the counts of total zooplankton in different water bodies were very less, as such the zooplankton counts varied between 3 to 6Nos/l. On comparing different groups it was observed that rotifer dominated the zoo-planktonic counts followed by Copepoda, nauplii and cladocera. The relationship between zooplankton, primary productivity and physico-chemical parameter were also calculated statistically. The present investigation also finds out the fish growth parameters like net weight gain Catla (857.71-950.95gm), Rohu (669.66-830.24gm) and Mrigal (461.82-752.01gm), net length gain Catla (20.82-24.92cm), Rohu (17.00-25.42cm) and Mrigal (15.98-24.64cm) and specific growth rate Catla (2.057-2.100%), Rohu (2.016-2.105%) and Mrigal (1.902-2.104%) and indicates the moderate productivity of the selected micro-watersheds. Further study is recommended to have better supplementary feeding and scientifically culture base fisheries for good results for fish production in micro-watersheds.