Impacts of recent rainfall changes on agricultural productivity and water resources within the Southern Western Ghats of Kerala, India.

Significant changes in rainfall patterns are critical to agriculture, and the dependency of cropping systems on rainfall variability would engender appropriate farming practices and agriculture policies for a climate-resilient agriculture system. This study analyses the significance of rainfall variability on agriculture productivity in the Wayanad district of Kerala (India) using time series data on rainfall (1989-2019) and crop yield (2000-2019). The spatial variability of rainfall patterns reveals a dichotomy between the rain gauge stations in the northern and southern parts of the region.

Appraisal of groundwater quality for drinking and irrigation suitability using multivariate statistical approach in a rapidly developing urban area, Tirunelveli, India.

The quantitative and qualitative stress on groundwater resources has been witnessed across the globe. The current study assesses the groundwater quality of Tirunelveli district which faces the hazard of groundwater contamination through seepage of toxins, considering the open dumping of huge volumes of solid waste. The findings from this study confirmed the presence of more than 20% samples in the "poor to very poor" quality with high concentrations of TDS, Cl, and NO, unfit for drinking, and other domestic purposes.

A coastal Ramsar site on transition to hypoxia and tracking pollution sources: a case study of south-west coast of India.

Coastal lakes and estuaries are considered economic drivers for coastal communities by delivering invaluable economic and ecosystem services. The coastal ecosystems are facing recurrent hypoxia events (dissolved oxygen; DO < 2.0 mg L) and are emerging as a major threat to ecosystem structure and functioning.

Application of radon (Rn) as an environmental tracer in hydrogeological and geological investigations: An overview.

Radon (Rn) is a colourless, odourless, inert, and radioactive noble gas (t = 3.8 days) that emanates from rocks and soils as a result of the alpha decay of its parent, radium (Ra) in the decay series of uranium-238, is the focus of this study. Radon is produced in the crystal lattice of the minerals and emanates out through alpha recoil.

Analysis of potential of Napier grass, Vetiver and Equisetum plants for the treatment of domestic greywater using box-type constructed wetlands.

The management of wastewater generated as a byproduct of various human activities from agricultural, industrial, and domestic sectors is a matter of global concern today. Greywater is a class of wastewater generated from the domestic sector. Greywater management can be done effectively by treating greywater at the source itself.

An appraisal of nutrient status and productivity with emphasis on phytoplankton assemblage in Karamana River, Kerala, India.

Nutrient pollution of rivers is one of the prime threats facing the aquatic systems. In the present study, water samples (n = 20) were collected from the Karamana river (KR) during the pre-monsoon (PMN) and monsoon (MN) seasons of 2019 to analyze the seasonal variations. The water samples were analyzed for various physico-chemical parameters and to understand the nutrient status of the river.

Factors controlling the distribution of radon (Rn) in groundwater of a tropical mountainous river basin in southwest India.

Studies on occurrence of radon in the environment are receiving growing attention worldwide due to its adverse impact on human health. Despite that, the dissolved radon in water is found to be a useful tracer in many hydrogeological studies. Although, several studies focused on the occurrence of high Rn in groundwater, the processes responsible for its variation is still not well understood.

Evaluation of radiation dose from radon ingestion and inhalation in groundwater of a small tropical river basin, Kerala, India.

A comprehensive study was conducted to understand the radon (Rn) distribution and associated radiation doses to the public in a small tropical river basin partly set in the western slope of the Southern Western Ghats of Kerala, India. Radon, though detected in all the 71 monitored wells (0.17-68.

Appraisal of nutrient distribution in the surface water and bed sediments of a small mountainous river.

A total of 42 (21 surface water and 21 bed sediments) samples were collected from upstream to downstream stretches of Meenachil river during pre-monsoon (PRM), monsoon (MON) and post monsoon (POM) seasons. DOC in water showed increasing trend spatially while temporal study illustrates high mean value during PRM (1.58 ppm) followed by POM (0.

Factors affecting the environmental carrying capacity of a freshwater tropical lake system.

Environmental carrying capacity is a measure of competence of a lake to accommodate pollution inputs without degrading water quality. In the research reported here, we identified the factors influencing the environmental carrying capacity of Vellayani Lake or VL (a typical tropical freshwater lake), Thiruvananthapuram, Kerala State, India. R-mode factor analysis is used to identify the factors controlling the carrying capacity of the lake, whereas hierarchical cluster analysis (HCA) helped to classify the lake.

Discriminant analysis for characterization of hydrochemistry of two mountain river basins of contrasting climates in the southern Western Ghats, India.

Discriminant analysis (DA) was performed on river hydrochemistry data for three seasons (i.e., monsoon (MON), post-monsoon (POM), and pre-monsoon (PRM)) to examine the spatio-temporal hydrochemical variability of two mountain river basins (Muthirapuzha River Basin (MRB) and Pambar River Basin (PRB)) of the southern Western Ghats, India.

Effect of nutrients on bioaccumulation of heavy metals in a tropical urban coastal lacustrine system.

The study on bioaccumulation of heavy metals in a lake reveals that during the nonrainy season, accumulation of cadmium in plankton is high in the upstream of the lake where anoxic freshwater condition exists resulting from inflow of urban wastes. Stern action is required to stop the bypass of sewage from the old sewer system especially in the commercial areas of Thiruvananthapuram city, either by augmenting the sewerage system or by treating sewage at the source. During monsoon season, the accumulation of heavy metals-namely lead and nickel, followed by cadmium and chromium-is high in phytoplankton resulting from high nitrate content caused by heavy rainfall.

Identification of hot spot area of sediment contamination in a lake system using texture characteristics.

Texture plays an important role in the identification of polluted stretch in a lake system. The organic matter as well as toxic elements get accumulated in the finer sediments. The aim of the work is to show the spatio-temporal distribution of texture of the lake sediment (Akkulam-Veli lake, Kerala) and to identify the hot spot areas of contamination.

Distribution pattern and factors affecting heavy metals in a lake system.

Heavy metals are widespiead pollutants of great environmental concern as they are non degradable, toxic and persistent.with serious ecological ramifications on aquatic ecology. The objective of this study is to analyse the spatio-temporal variation of heavy metals in the sediments of a lake system (Akkulam-Veli lake, Kerala).

Influence of lake morphology on water quality.

Lakes are seriously affected due to urban pollution. The study of the morphological features of a lake system helps to identify its environmental status. The objective of the present study is to analyse the influence of morphometry on water quality in a lake (Akkulam-Veli Lake, Thiruvananthapuram, Kerala).

Environmental status of a tropical lake system.

Eutrophication has become a serious threat to the lake systems all over the world. This is mainly due to the pollution caused by anthropogenic activities. Carlson trophic state index (CTSI) is commonly used for the classification of trophic conditions of surface waters.

Heavy metal concentration in the coastal wetlands of Thiruvananthapuram district, southern India.

Levels of heavy metals (Cu, Cr, Pb, Zn, Fe and Mn) in the surficial sediments of the four coastal wetlands, viz. Poovar, Poonthura, Akkulam-Veli and Kadinamkulam-Anjengo-Akathumuri of Thiruvananthapuram are presented in this study. Further the statistical tools like contamination factor (CF), index of geoaccumulation (Igeo) and pollution load index (PLI) are used to assess the heavy metal pollution.

Trophic state index of a lake system using IRS (P6-LISS III) satellite imagery.

Water pollution has now become a major threat to the existence of living beings and water quality monitoring is an effective step towards the restoration of water quality. Lakes are versatile ecosystems and their eutrophication is a serious problem. Carlson Trophic State Index (CTSI) provides an insight into the trophic condition of a lake.