No abstract

Pakistan’s most of the land is less productive or no productivity at all due to erosion and salinity of the soil, which can be utilized to develop fisheries. The project, “Survival, growth and body composition of Cyprinus carpio under different salinity regimes” was undertaken in two phases. In the first phase susceptibility of Cyprinus carpio at four salinity levels in triplicate within 0–10 g L −1 NaCl for 96 h in each aquarium was checked after one week acclamation at 0 g L −1 , 2 g L −1 and 4 g L −1 NaCl. LC 50 values varied from 7.67 to 10.65 g L −1 after 96 h for C. carpio. Percentage mortality of the fish and important water quality parameters after every 12 h were observed for a period of 96-h. Probit analysis showed that 96-h LC 50 values ranged from 7.67 to 10.65 g L −1 . During experimental period aquaria water temperature ranged from 29.6 to 33.7 °C, pH values fluctuated between 7.8 and 9.7, Electrical conductivity values ranged from 2.40 to 20.13 dSm −1 and Dissolved oxygen ranged between 2.23 and 10 mg L −1 . Sub-lethal salt concentration i.e. 0 g L −1 to 3 g L −1 NaCl upto 40 days showed that growth of C. carpio decreased with the increase of water salinity levels and ceased at 4 g L −1 salinity and increase in salinity have negatively affected hematological parameters.

In the Indus Basin of Pakistan, multi-strainer shallow tubewells often called 'skimming wells' are used to extract groundwater from thin fresh lenses underlain by saline groundwater. Most of these wells face problems such as deteriorating water quality and reduction in discharge due to inadequate design and poor operational and management strategies. This paper evaluates the current practices of farmers in the Chaj doab area of Pakistani Punjab and suggests improvements in design and operation of skimming wells to ensure long-term sustainability of irrigated agriculture in the area. The effect of existing design and operation of skimming wells on pumped groundwater quality was evaluated using MODFLOW. To study the long-term effects of skimmed groundwater use on crop production and soil salinity development, the soil water flow and solute transport model SWAP was applied. The results revealed that farmers could reduce the number of strainers from 16 to 6 without reducing the anticipated discharges. For the conditions considered, the maximum discharge of skimming wells should be 4–8 L/s and they should not be operated for more than 2–4 h per day. Increasing discharge rate or daily operational hours can disturb the interface between fresh and saline groundwater resulting in reduced quality pumped groundwater. Weekly operational schedules together with recommended discharge rate and operational hours will be the best strategy to use skimmed groundwater for achieving optimal crop yields while maintaining root-zone salinity within acceptable limits. To avoid aquifer degradation, skimming wells should be used for supplemental irrigation rather than full irrigation of crops. Due to low discharge rates, skimming wells cannot be used to irrigate crops through surface irrigation methods. Therefore, pressurised irrigation methods should be used. The results also suggest that continuation of present irrigation practices could lead to serious problems of land and aquifer degradation. Therefore, farmers need to adjust their irrigation and leaching requirements annually considering crop evapotranspiration, precipitation, and salinity status of soils.

Tramadol is an analgesic and psychoactive drug that acts primarily upon the central nervous system where it alters brain function, resulting in temporary changes in perception, mood, consciousness and behavior. The aim of present study was to analyze the genotoxicity and repair capability of DNA after Tramadol exposure in albino mice (Mus musculus). For this purpose, forty mice were divided equally into four groups as; a control group (without drug) and three treatment groups that were treated with three doses of Tramadol as minimum dose group, Intermediate dose group and maximum dose group, corresponding to 25 mg/kg, 50 mg/kg and 75 mg/kg of body weight respectively. The dose was given orally for 15 days. After 15 days peripheral blood was drawn from half mice of each group and subjected to comet assay. While the remaining half mice were given a recovery period of 15 days and same procedure was used for blood collection and comet assay. Significant difference in various comet parameters was observed among control and exposed groups. Maximum damage was observed at highest concentration 75 mg/kg of Tramadol and minimum damage was observed at dose 25 mg/kg of Tramadol, while results of repaired mice group showed that repair capability of Tramadol was minor and recovery of Tramadol required a lot of time. It can be concluded that Tramadol cause genotoxicity that is dose dependent and has low repair capability.

Cyprinus carpio fingerlings were taken to measure acute toxicity in a set of four concentrations with three acclimation in triplicate of rock salt at 35 °C temperature which was prepared in the glass aquaria of each having dimensions 30L × 30W × 45H cm (40.5 liters water capacity) for 96hrs. Five fishes were stocked in each aquarium. Observations on fish mortality in all aquaria was observed and recorded for 2 months to determine the salinity effect on growth parameters. Important physico-chemical parameters of aquaria water, such as temperature, dissolved oxygen, pH, electric conductivity, total dissolved solids and chloride were observed using professional meter (HANNA HI 9828). Rate of mortality was increased with the increase of salt and temperature. The statistical analysis of variance of pH and pH (mV) differences was highly significant among salt and time while less significant among temperature values.