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It is well renowned that trees have capacity to reduce the air pollution. It is mandatory to expand tree plantation in industrial area to minimize the threat of pollutants. For green belt development, it is necessary to use plants that are tolerant to air pollution. The present study includes Air pollution tolerance index (APTI) of selected plant species with the help of biochemical analysis. On the basis of APTI and some other socioeconomic and biological parameters of plants, Anticipated Performance Index (API) was calculated. Out of twelve species, Ficus benghalensis showed to be the most efficient among others. As per classification of API, Ficus religiosa tree species is classified into the moderate category. Based on the APTI and API, appropriate plant species for green belt development in industrial area were identified and recommended for mitigating the pollution.

Fish is an essential component of the diet of the most populace in Assam and fish farming has been one of the sources of livelihood in rural areas. Assam ranks first in fish production among North-eastern states of India. However, fish production is not sufficient to meet the demand despite having vast aquatic resources in the state. The present study was undertaken to determine the decadal growth of fish production in the state using the compound growth rate. The study also attempted modeling and forecasting of fish production in Assam using Auto-Regressive Integrated Moving Average (ARIMA) methodology. For the present study, time-series data on fish production in Assam from 1980-81 to 2018-19 was obtained from the Directorate of Fisheries, Government of Assam. Data for the period 1980-81 to 2014-15 was utilized to build an ARIMA model and validated through the remaining data from 2015-16 to 2018-19. The best suitable model for the state’s fish production was ARIMA (1,1,0) based on the values of the model selection criterion. The actual fish production and forecast values using a fitted model were in close agreement. The out-of-sample forecast values of fish production in the state for the subsequent years 2019-20 to 2022-23 showed an increasing trend from 336.97 to 358.21 thousand metric tonnes. Considering the vast aquatic resources in the state, the study calls for serious attention by policymakers, researchers, and developmental agencies for harnessing the potential of fisheries resources for making the North-east region self-sufficient in fish production as a whole and Assam in particular.

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Nirmal Kumar et al.: Assessment of spatial and temporal fluctuations in water quality of a tropical permanent estuarine system -267 - Abstract.A study pertaining to seasonal variation in physicochemical properties was carried out at five sites of Tapi estuarine zone for a period of one year i.e. July 2008 to June 2009. It revealed that the estuarine zone was significantly influenced by freshwater input during monsoon and post-monsoon periods. Concentration of all the nutrients and dissolved oxygen (DO) was relatively high during the monsoon, whereas, and salinity were at their minimum level during this period. Phytoplankton production peak in terms of chlorophyll-a (Chl a) was observed in summer and winter during which a typical marine condition prevailed. In present study observed correlated values of salinity, nitrate, phosphate, silicate, values are significantly high in the estuarine zone. Cluster analysis carried out for both monthly and station-wise and average values gives different clusters depending on the affinity and relation between months and sites due to environmental conditions prevailed in the estuary zone. Principal Component Analysis (PCA) was used in the ordination of samples (site, season and physicochemical parameters). The PCA was performed using all variables, Eigenvalues accounts and Scree plot showed that the first three Principal Components are the most significant components which represent more than 75% of the variance in water quality parameters in Tapi estuary, 48.5% by PC1, 14.4% by PC2 and 12.1% by PC3.