Superabsorbent nanocomposite hydrogels based on polyacrylamide (PAAm), cashew tree gum (CG), and laponite (LAP) were synthesized in different concentrations to investigate swelling, thermal, morphological and rheological properties. Vibrational modes confirmed the formation of hydrogels, while X-ray diffraction patterns reveal the semi-crystalline structure of the hydrogels. Thermal analysis showed that higher LAP content and CGLAP interactions improved the thermal stability of the hydrogels. Morphology analysis presented porous structures in CG-based hydrogels, contrasting with irregular plate-like structures in those without CG. The swelling capacity had better results in hydrogels with CG that were subjected to alkaline hydrolysis, mainly in a buffer solution with a pH > 4, due to the ionization of the hydrophilic groups. Hydrogels containing LAP maintained swelling degree stability at pH 10 and 12. In rheological tests, the addition of LAP increased the viscosity of the hydrogels, significantly improving the mechanical resistance of the hydrogels. Rheological parameters, such as the storage modulus (G ') and loss modulus (G ''), indicated that the materials exhibited predominantly solid behavior, particularly in CG-LAP-rich hydrogels. Low mortality of Artemia salina nauplii in toxicity tests confirmed material safety. The results indicate that CG-LAP hydrogels are promising for agricultural applications, offering optimized swelling properties, thermal stability, and mechanical strength.

Weak clayey soils in construction are considered problematic due to their high compressibility and low bearing capacity. This study proposes an environmentally friendly replacement for conventional soil stabilizers through the use of geopolymer (GP) containing Cashew Nut Shell Ash (CNSA) to improve soil characteristics. In this study, the CNSAGP was compared with lime-stabilized soil for unconfined compressive strength (UCS), durability, and improved microstructure. The experimental outcomes showed that 9 M + CNSAGP with 4% CNSA provided a UCS of 1900 kPa, which was higher than the lime-stabilized soil (6% lime with 4% CNSA) at 1400 kPa. Durability test results revealed that the CNSAGP-treated sample had better protection against water damage with a strength loss of about 18%, while the lime-treated sample had a strength loss of about 25%. Thermal stability analysis showed that CNSAGP had lower LOI values compared to lime-stabilized samples (0.17% at 900 degrees C), which indicates CNSAGP's heat resistance. Microstructure analysis revealed that CNSAGP-stabilized soil was less porous, the microstructure being denser because of reactions of aluminosilicate and pozzolanic activity. Moreover, it affected the soil's alkalinity, making it better, and improved Atterberg limits, which affected the plasticity and workability. These findings show that CNSAGP is a long-lasting and eco-friendly means of soil stabilization with higher strength, thermal stability, and durability than traditional methods and can be used in engineering.

Cashew is usually grown as a rainfed crop in ecologically sensitive areas such as coastal belts, hilly areas and areas with high rainfall and humidity, andhence its performance mainly depends on climate. Studies on suitability of cashew cultivation in India using GIS showed that cashew grows at an elevation ranging from 0 to 1000 m above MSL. However, the productivity is the highest up to the altitude of 750 m above MSL. The average annual rainfall distribution in cashew areas ranges from low rainfall (300-600 mm in Gujarat) to high rainfall (2700-3000 mm in west coast and NEH region) but the productivity is highest in regions with a mean annual rainfall distribution of 600-1500 mm. The productivity of cashew is higher in regions where the minimum temperature ranges from 10 to 22 square C and is lower in regions where the minimum temperature drops below 10 degrees C. Unseasonal rains and heavy dew during flowering and fruiting periods are the major factors which adversely affect the nut yield. Heavy rains at the time of harvesting affects yield and quality of nuts. Cloudy conditions, high RH and heavy dewfall are favorable for outbreak of insect pests and diseases. To circumvent losses due to climate variability/change, adaptation and mitigation strategies are essential in affected areas. Some of the adaptation strategies include plant architecture, use of efficient technologies like drip irrigation, soil and moisture conservations measures, fertilizer management through fertigation, green manuring/intercropping, increase in input efficiency, pre and post-harvest management of economic produce cannot only minimize the losses but also increase the positive impacts of climate change. The flowering, fruiting, insect pest incidence in cashew crop, yield and quality of cashew nut and kernels are more vulnerable attributes for climate change. The sea water level rise due to the melting of glaciers as a result of increase in temperature may also pose problem for cashew cultivation since large proportion of cashew plantations exist in Eastern and Western Coastal regions of India. The perennial cashew crop has potential for carbon sequestration for mitigation of climate change.