Search

Rainfall serves as a lifeline for crop cultivation in many agriculture-dependent countries including India. Being spatio-temporal data, the forecasting of rainfall becomes a more complex and tedious process. Application of conventional time series models and machine learning techniques will not be a suitable choice as they may not adequately account for the complex spatial and temporal dependencies integrated within the data. This demands some data-driven techniques that can handle the intrinsic patterns such as non-linearity, non-stationarity, and non-normality. Space–Time Autoregressive Moving Average (STARMA) models were highly known for its ability to capture both spatial and temporal dependencies, offering a comprehensive framework for analyzing complex datasets. Spatial Weight Matrix (SWM) developed by the STARMA model helps in integrating the spatial effects of the neighboring sites. The study employed a novel dataset consisting of annual rainfall measurements spanning over 50 (1970–2019) years from 119 different locations (grid of 0.25 × 0.25 degree resolution) of West Bengal, a state of India. These extensive datasets were split into testing and training groups that enable the better understanding of the rainfall patterns at a granular level. The study findings demonstrated a notable improvement in forecasting accuracy by the STARMA model that can exhibit promising implications for agricultural management and planning, particularly in regions vulnerable to climate variability. [ABSTRACT FROM AUTHOR]

Kenaf, also known as Deccan hemp (Hibiscus cannabinus L.) is the one of the most important, hardy and economic bast fiber industrial crops. Sulfur plays a significant role in determining yield and quality of fiber crops. However, the effect of sulfur application on yield, nutrient uptake in kenaf varieties, agronomic efficiency, apparent S recovery, and nutrient availability and sulfur fractions is still unclear. Thus, the present investigation was carried out to study the effect of sulfur (S) fertilization (S0= Control, S15=15kg S ha−1, S30=30kg S ha−1, S45=45kg S ha−1) on fiber yield, nutrient uptake, nutrient availability and S fractions of experimental soil and to screen the kenaf varieties ('JBM-2004-D', 'MT-150', 'AMC-108' and 'HC-583') for higher S use efficiency and increased productivity. Compared to control (S0), S45 treatment significantly increased fiber yield of kenaf by 37%. MT-150 produced the highest fiber yield (2.61 t ha−1). Among the S levels, S45 exhibited lowest value of agronomic efficiency (16.5 kg kg−1 S), apparent S recovery (18.7%) and highest value of nutrient uptake in kenaf. Results also revealed that nutrient availability (nitrogen, phosphorus and potassium) increased with increase in S levels at all soil depths and the nutrient status decreased with depth. Sulfur fractions (total S, organic S, adsorbed S, plant available S) increased with increasing S levels and followed the order as organic S > non-sulfate S > adsorbed S > plant available S. In addition, organic sulfur contributed 63–74% of total sulfur. Thus, the results suggest that by selecting appropriate variety and level of sulfur (@ 30 kg ha−1) for kenaf cultivation farmers can obtain higher fiber yield for sustainable crop production. [ABSTRACT FROM AUTHOR]

Present study is a maiden attempt to assess net ecosystem exchange (NEE) of carbon dioxide (CO2) flux from jute crop (Corchorus olitorius L.) in the Indo-Gangetic plain by using open-path eddy covariance (EC) technique. Diurnal variations of NEE were strongly influenced by growth stages of jute crop. Daytime peak NEE varied from − 5 µmol m−2 s−1 (in germination stage) to − 23 µmol m−2 s−1 (in fibre development stage). The ecosystem was net CO2 source during nighttime with an average NEE value of 5–8 μmol m−2 s−1. Combining both daytime and nighttime CO2 fluxes, jute ecosystem was found to be a net CO2 sink on a daily basis except the initial 9 days from date of sowing. Seasonal and growth stage-wise NEEs were computed, and the seasonal total NEE over the jute season was found to be − 268.5 gC m−2 (i.e. 10.3 t CO2 ha-1). In different jute growth stages, diurnal variations of NEE were strongly correlated (R2 > 0.9) with photosynthetic photon flux density (PPFD). Ecosystem level photosynthetic efficiency parameters were estimated at each growth stage of jute crop using the Michaelis–Menten equation. The maximum values of photosynthetic capacity (Pmax, 63.3 ± 1.15 µmol CO2 m−2 s−1) and apparent quantum yield (α, 0.072 ± 0.0045 µmol CO2 µmol photon−1) were observed during the active vegetative stage, and the fibre development stage, respectively. Results of the present study would significantly contribute to understanding of the carbon flux from the Indian agro-ecosystems, which otherwise are very sparse. [ABSTRACT FROM AUTHOR]

Soil resources are prone to degradation in harsh hill environment. Conservation tillage and residue mulching play an important role in protecting and improving soil quality. A 4-year study was conducted in Meghalaya, India, involving maize ( Zea mays L.)-rapeseed ( Brassica campestris L.) cropping system, to evaluate the impact of no till (NT) and mulching on productivity of maize-rapeseed system and to assess the effect of management on soil organic carbon (SOC) and quality. Two tillage practices, conventional tillage (CT) and NT, were compared under six mulching rates: control (no mulching); M, maize stover retention; MA5, M + ragweed (RW; Ambrosia artemisiifolia) 5 Mg ha−1; MA10, M + RW 10 Mg ha−1; MF10, M + farmyard manure 10 Mg ha−1; and MA5P5, M + RW 5 Mg ha−1 + poultry manure 5 Mg ha−1. Grain yields of maize and rapeseed under CT were similar to those under NT. Mulching had a significant effect on the productivity of maize and rapeseed. Mulching treatment MA5P5, MF10 and MA10 produced significantly ( p = 0·05) higher yield of maize and rapeseed than that of other treatments. Maize and rapeseed productivity under control was the lowest. There was a marked increase in SOC concentration (8·4%), water stable aggregates (9·3%), mean weight diameter (42·6%) and soil microbial biomass carbon (66·8%) under NT, with respect to CT. Mulching treatment MA5P5 enhanced mean SOC concentration by 30·4% and mean weight diameter by 100% compared with those under control. Thus, NT and mulching are recommended measures for protecting soil and improving its quality in the studied area. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]