Mahendra Prasad

Sewage water (SW) use is a common practice for crop production in peri-urban areas globally, especially in arid and semi-arid environments. While it enhances crop yields, it also raises potential ecological and health risks from heavy metals (HMs) contamination, requiring effective management strategies. The study examined the long-term (> 20 years) impact of SW irrigation on HM contamination in the water-soil-fodder-livestock continuum in central India. Samples of SW, groundwater (GW) (pre-monsoon, monsoon, and post-monsoon seasons), soil, fodder, and milk were collected over three years (2018–2021) to evaluate HMs levels, fodder quality, soil pollution indices, and livestock health risks. Findings revealed elevated HMs concentrations in SW, especially during the pre-monsoon. The SW irrigation improved soil fertility (SOC, N, P and K, ~ 14%, ~ 8%, ~ 44% and ~ 12%, respectively) and fodder quality over GW. Soils in Bhopal recorded the highest Cr (51.47 mg kg⁻¹) and Ni (55.35 mg kg⁻¹), while Cd (1.34 mg kg⁻¹), Pb (26.41 mg kg⁻¹) were highest in soils from Varanasi and Kanpur, respectively. Cr and Pb levels exceeded permissible limits. Fodder irrigated with SW showed significantly higher HM accumulation (Cd: ~ 27%, Ni: ~ 44%, Pb: ~ 42%) than with GW. Milk samples exceeded safe limits for Cr, Cd, and Pb, indicating human health risks. Soil indices identified Cd as the primary ecological risk. Although metal transfer factors were < 1.0, Ni and Pb health risk indices surpassed safe thresholds, potentially impairing livestock immunity and productivity. The study underscores the urgent need for regulated SW reuse, farmer education, and policy intervention to ensure sustainable livestock systems.

Sewage water (SW) irrigation is widely used in developing countries, particularly in arid and semi-arid regions, as a cost-effective method for crop production. However, it poses significant ecological and health risks owing to the presence of heavy metals (HMs), necessitating effective management strategies. This study assesses the impact of mixing SW with groundwater (GW) in various ratios (SW₀: 0%SW, SW₂₅: 25%SW, SW₅₀: 50%SW, SW₇₅: 75%SW, and SW₁₀₀: 100%SW) on fodder productivity, HMs accumulation, and associated risks to livestock in Jhansi, Uttar Pradesh, India. Over three years, SW irrigation improved soil fertility and increased fodder yields by 6–25%. However, it led to elevated levels of HMs in the soil–fodder system. Among the crops studied, oat showed the lowest bioaccumulation compared to cowpea, maize, and berseem, with Pb levels exceeding permissible limits in the SW₁₀₀ treatment. Most tested crops exceeded WHO/FAO limits for HMs, except for Cr and Cd in the SW₂₅ treatment. Pollution index values categorized all crops as “severely” to “heavily polluted”, except for oat. Ecological risk indices were low for SW₀ to SW₅₀, with Cd presenting the highest ecological risk (38–69%). The transfer factor (TF) for Cr, Ni, and Cd was 1, signaling health risks to immune function, productivity, and reproductive performance in livestock consuming SW-irrigated fodder. A blend of lesser metal-accumulating fodder crops and a 1:3 SW: GW dilution ratio can effectively minimize these risks. Our findings provide baseline information to policymakers, environmentalists, and livestock keepers for formulating strategic mitigation plans to minimize the potential future risks of HMs pollution in the soil-fodder-livestock continuum.

A study was carried out to examine the effects of different potassium fertilizer sources on growth, fodder yield and quality at the Research Farm, Rani Lakshmi Bai Central Agricultural University, Jhansi, Uttar Pradesh. The experiment was conducted under semi-arid climatic conditions in a simple Randomized Block Design (RBD) with ten treatments (control, 100% NP, 100% recommended dose of potassium (RDK) through MOP, 100% RDK through SOP, 100% RDK through POLY4, 75% RDK+ 1% RDK foliar spray (30 days after sowing and 30 days after fodder harvest) through POLY4, 100% RDK through schoenite and 75% RDK+ 1% RDK foliar spray (30 days after sowing and 30 days after fodder harvest) through schoenite, 75% RDK through MOP + KSB (potassium solubilizer bacteria, Seed treatment), KSB alone (Seed treatment) and three replications. Results showed that application of 75% RDK+ 1% RDK foliar spray (30 days after sowing and 30 days after fodder harvest) through POLY4 recorded the significantly highest growth and yield contributing parameters, which is beneficially resulted in increased green fodder yield (159%) as compared to control. However, it was at par with the application 75% RDK+ 1% RDK foliar spray (30 days after sowing and 30 days after fodder harvest) through schoenite. The fodder quality parameters viz. CP, ADF, and NDF were also remarkably improved with the application of 75% RDK+1% RDK foliar spray (30 days after sowing and 30 days after fodder harvest) through POLY4 in oat crop. The results imply that farmers may apply 75% RDK+1% RDK foliar spray through POLY4 to achieve good quality higher green fodder in sandy clay loam soil for oat production.

Pastures may act as carbon sources and sinks depending on grazing pressure and management practices. Soil organic carbon (SOC) stock and its fractions were quantified under 3 different grazing intensities using 5, 10 and 15 sheep/ha under sown, improved and natural pastures in the semi-arid tropics of India. Results revealed that after 3 years, improved pasture had significantly higher particulate organic carbon (POC ~4.5 g/kg), SOC (~0.53 %), total organic carbon (TOC~7 g/kg) and SOC stock (~15 mg/ha) as compared with sown and natural pastures. Labile carbon (LC ~185 mg/kg) and soil microbial biomass carbon (SMBC ~378 µg/g soil) were higher under natural pasture. A moderate grazing intensity of 10 sheep/ha resulted in significantly greater carbon fractions, TOC and SOC stock. SOC stock and its fractions were significantly higher in the topsoil layers as compared with the subsoil layers. These results indicate that improved pasture management practices with moderate grazing intensity can be recommended for improving SOC stock and its fractions in semi-arid tropical pastures.