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The interplay between soil nutrients, water activity, and microbial biomass is pivotal for plant growth as well as for soil health. While surface microflora typically promotes mineralization and nutrient deposits, the impact of drought on soil microbial biomass and nutrient utilization remains underexplored. In this study, we assessed various land types—open lands (OL), annual crops with single species (ACS), perennial crops with multiple species (PCM), less water available lands (LWA), and soil near ponds (CP)—to elucidate the distribution of macronutrients and microbial biomass. Soil samples were collected from different land types, air-dried, and subjected to physical, chemical, and biological analyses. Standardized protocols, including gravimetric and titration analyses, were employed for physical and chemical assessments, while microbial biomass was evaluated using fumigation. Statistical analyses, including ANOVA and Pearson Coefficient, were employed to discern patterns across seasons, soil depths, and microbial biomass. Microbial biomass carbon (Cmic) ranged from 134.2±1.2 μg/g to 286.6±1.33 μg/g, while nitrogen (Nmic) and phosphorus (Pmic) varied from 11.3±1.3 μg/g to 69.5±0.98 μg/g and 07.6±1.5 μg/g to 77.5±0.6 μg/g, respectively, across all seasons. Carbon stock in the upper soil surface positively influenced nitrogen and phosphorus retention. Notably, PCM exhibited superior Cmic, Nmic, Pmic, and water-holding capacity compared to OL, LWA, and ACS. Our findings underscore the significance of multiple cropping systems, particularly PCM, in enhancing microbial biomass and nutrient levels in drought-affected regions. The observed improvements in soil moisture, nitrogen, phosphorous, and potassium levels suggest that diverse cropping systems can effectively enrich soil nutrients and biomass content in drought stress. In conclusion, our study highlights the potential of perennial crops with multiple species in mitigating the impact of drought on soil microbial biomass and macronutrient distribution. These findings contribute to a deeper understanding of sustainable agricultural practices in drought-prone regions and emphasize the importance of implementing diverse cropping systems to enhance soil health and resilience. [ABSTRACT FROM AUTHOR]

Invasive plant species pose a serious threat to agricultural yield, although how the threat varies with the distance of crops from invasive plants remains unclear. Therefore, utilizing this viewpoint, objectives were formulated to quantify differences in the native vegetation and performance of crops growing near A. adenophora–invaded (treatment plots) and uninvaded ridges (control plots) in the terraced agricultural fields of Kumaun Central Himalaya. Morphological and yield parameters of two crops, viz. rice (Oryza sativa L.) and soybean (Glycine max L.), were assessed systematically by laying parallel transects from the ridge of the field up to 5 m towards the centre of the field in three equal distance intervals of 1 m in the order: 0–1 m, 2–3 m, and 4–5 m. Crofton weed showed 95–100% crown cover throughout invaded ridges/risers of terraced fields, with stem densities of 134–208 ind. m−2 and an average basal area of 0.15 cm2. The total mean density of herbs (other than A. adenophora) in invaded ridges/risers decreased by 38–85% compared to uninvaded ridges, but species richness increased by 31–37%. Soil nutrient availability was high across invaded ridges/risers as well as crop fields. The average irradiance level near uninvaded ridges was 19.6 ± 1.80%, and near invaded ridges, it was 1.8 ± 0.31%. Compared to straw, root, and grain yields obtained at the farthest distance, the yield of rice near uninvaded ridges was reduced by 27%, 19%, and 33%, while near invaded ridges, it was reduced by 37%, 39%, and 43%, respectively; the yield of soybean near uninvaded ridges declined by 62%, 66%, and 42%, while near invaded ridges, it decreased by 59%, 69%, and 47%, respectively. Compared to the values obtained at the farthest distance, the harvest index (HI) of rice near ridges was reduced by 7% and 13%, while the HI of soybean increased by 15 and 10% across uninvaded and invaded field ridges, respectively. The findings indicated that the Crofton weed could suppress field crops and could form a single dominant population in the invaded area, causing a serious threat to the plant community, its diversity, and the yield of the native agroecosystem in the foreseeable future if timely management actions would not be taken. [ABSTRACT FROM AUTHOR]

Herbaceous entity plays a significant role in the structural dynamics of natural ecosystems and its responsibility increased by many times in case of agricultural systems. The present study has been performed to assess the ecological performance, biomass, carbon stock, and CO2 mitigation potential of the herbaceous layer in Central Himalayan agroecosystems of India. Four different altitudes have been selected viz. very low altitude (< 450 m; VLA), low altitude (450–900 m, LA), mid altitude (900–1500 m; MA) and high altitude (1500–2200 m, HA) and samples studied in a stratified manner (4 altitudes × 3 agroecosystems × 3 replicates × 3 seasons = 108 samples). A total of 41 herbs (21 cultivated + 20 wild) species belonging to 16 families were recorded within agroecosystems and results depicted that maximum species encountered during the rainy season (30) followed by summer (18) and winter season (12). The regression analysis between herb density and diversity depicted that the diversity (MA > HA > VLA > LA) showed just inverse pattern of herb density (LA > VLA > HA > MA), which indicates that increasing density may results in the dominance of one or two species thus downgrading the diversity. Brassica oleracea spp., Eleusine coracana, Solanum tuberosum, Solanum lycopersicum, Pisum sativum, etc. were common and proliferated cash crops towards higher altitudes, while low altitude agroecosystems were dominated by grain and pulse crops (Oryza sativa, Triticum aestivum, Zea mays, Glycine max, Vigna mungo, etc.). These crops are responsible for the higher biomass and higher C stock in agroecosystems, together with they are fulfilling the multifarious needs of adjacent communities. [ABSTRACT FROM AUTHOR]