Assessment of groundwater salinity using principal component analysis (PCA): a case study from Mewat (Nuh), Haryana, India.

In the present study, principal component analysis (PCA) is used to investigate the processes controlling groundwater salinity in the Mewat (Nuh) district, Haryana, India. Twenty groundwater samples were collected from salinity-affected areas in the March-April months of years 2018 and 2019 and were analyzed for chemical variables pH, EC, Ca2+, Mg2+, Na+, K+, [Formula: see text], Cl-, SO42-, [Formula: see text], TDS, and total hardness. Three principal components were selected based on the eigen value, which explains 79.58% and 85.08% of the total variation in the years 2018 and 2019, respectively. The first principal component (PC-1) is identified with salinity, the second principal component (PC-2) with alkalinity, and the third principal component (PC-3) described the pollution. When the yearly comparison was made, the samples collected in 2019 were found to have an increased salinity compared to 2018, which shows an increased vulnerability to the aquifer of Mewat on account of the decline in rainfall recharge. It was also evident that declining recharge also triggered the recharge from other sources; thus, the impact of pollution is more pronounced in 2019 compared to 2018.

Activity and distribution of carbonic anhydrase in the oviduct of the laying hen (Gallus domesticus) during egg formation at three different periods in spring and summer seasons.

Investigations were undertaken to study the possible role of oviducal carbonic anhydrase during egg shell formation in 108 layers of Babcock-300 strain of three age groups of 21-24, 32-36 and 68-72 week old during spring and summer. Eighteen layers of each age group were subgrouped in three cyclic positions just after oviposition, 4 and 18 hours after oviposition. The distribution of carbonic anhydrase was significantly (P less than 0.01) higher in shell gland and low in isthmus in all the three age groups during both seasons. Carbonic anhydrase decreased (P less than 0.01) in summer in all three age groups. It was significantly (P less than 0.01) higher in magnum at the 14th h after oviposition in all the three age groups in both seasons, which established a new pattern of activity. Decreased concentration of the enzyme during the thermal stress period might be one of the factors responsible for the thinness of egg shell and for the increase in the number of soft shelled eggs.