Browsing by Author "Singh R"
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- ItemA Review of Nutritional Water Productivity (NWP) in Agriculture: Why It Is Promoted and How It Is Assessed?(MDPI (Basel, Switzerland), 2023-12-14) Drastig K; Singh R; Telesca F-M; Carra SZ; Jordan J; Orange DAssessment of nutritional water productivity (NWP) combines a metric of crop or livestock production per unit water consumed and human nutritional value of the food produced. As such, it can rationalize the use of scarce water for a portfolio of crop and livestock production systems that jointly match human nutritional needs and reduce water scarcity impacts. However, a comprehensive search and review of 40 NWP studies highlighted that current NWP studies vary widely in terms of their methodological approaches, the data and tools used and the water flows and nutrient content accounted for. Most of the studies accounted for evapotranspiration stemming from precipitation and technical water, and/or inclusion of the withdrawn technical water. Water scarcity was only addressed in four studies. The reported NWP values also varied for accounting of macro- (energy, protein, fat and carbohydrates) and micro-nutrient (minerals and vitamins) content. The methodological differences, however, severely limit the informative value of reported NWP values. A multidisciplinary research effort is required to further develop standardized metrics for NWP, including its local environmental water scarcity impacts. A robust NWP analysis framework in agriculture should focus on the integration of assessments of NWP and water scarcity impact (WSI), and development of more field measurements and locally calibrated and validated agrohydrological and farm production models to quantify reliable NWP values and their associated WSI of agriculture production systems worldwide.
- ItemBuilding consensus on water use assessment of livestock production systems and supply chains: Outcome and recommendations from the FAO LEAP Partnership(Elsevier B.V., 2021-01-23) Boulay A-M; Drastig K; Amanullah; Chapagain A; Charlon V; Civit B; DeCamillis C; De Souza M; Hess T; Hoekstra AY; Ibidhi R; Lathuillière MJ; Manzardo A; McAllister T; Morales RA; Motoshita M; Palhares JCP; Pirlo G; Ridoutt B; Russo V; Salmoral G; Singh R; Vanham D; Wiedemann S; Zheng W; Pfister SThe FAO Livestock Environmental Assessment and Performance (LEAP) Partnership organised a Technical Advisory Group (TAG) to develop reference guidelines on water footprinting for livestock production systems and supply chains. The mandate of the TAG was to i) provide recommendations to monitor the environmental performance of feed and livestock supply chains over time so that progress towards improvement targets can be measured, ii) be applicable for feed and water demand of small ruminants, poultry, large ruminants and pig supply chains, iii) build on, and go beyond, the existing FAO LEAP guidelines and iv) pursue alignment with relevant international standards, specifically ISO 14040 (2006)/ISO 14044 (2006), and ISO 14046 (2014). The recommended guidelines on livestock water use address both impact assessment (water scarcity footprint as defined by ISO 14046, 2014) and water productivity (water use efficiency). While most aspects of livestock water use assessment have been proposed or discussed independently elsewhere, the TAG reviewed and connected these concepts and information in relation with each other and made recommendations towards comprehensive assessment of water use in livestock production systems and supply chains. The approaches to assess the quantity of water used for livestock systems are addressed and the specific assessment methods for water productivity and water scarcity are recommended. Water productivity assessment is further advanced by its quantification and reporting with fractions of green and blue water consumed. This allows the assessment of the environmental performance related to water use of a livestock-related system by assessing potential environmental impacts of anthropogenic water consumption (only “blue water”); as well as the assessment of overall water productivity of the system (including “green” and “blue water” consumption). A consistent combination of water productivity and water scarcity footprint metrics provides a complete picture both in terms of potential productivity improvements of the water consumption as well as minimizing potential environmental impacts related to water scarcity. This process resulted for the first time in an international consensus on water use assessment, including both the life-cycle assessment community with the water scarcity footprint and the water management community with water productivity metrics. Despite the main focus on feed and livestock production systems, the outcomes of this LEAP TAG are also applicable to many other agriculture sectors.
- ItemEvaluation of potential irrigation water savings by assessing the soil water balance in a vineyard in central Chile(John Wiley & Sons Ltd on behalf of International Commission for Irrigation and Drainage, 2024-05-26) Salazar O; Castro M; Singh R; Ponstein HThe main aim of this study was to evaluate the potential savings of irrigation water by assessing the soil water balance during the growing season in a wine vineyard in the Maule region, Chile. This study provides insights into the influences of different irrigation water applications on soil water status and its potential effects on grape yields, water use efficiency (WUE) and the cost of irrigation to help improve irrigation practices in the region and other similar Mediterranean regions. The field experiment compared three levels of irrigation water applied: current irrigation of the vineyard (T0) and two deficit irrigation treatments with reductions to 75% (T1) and 50% of the irrigated water (T2). The measurements included volumetric soil water content, shallow groundwater table, canopy cover and grape yield at harvest during the entire growing season (October 2017 to April 2018). We found a potential reduction of 25% or 50% in the current irrigation system while maintaining the grape yield, increasing the WUE and reducing the cost of irrigation. Consideration of the water stored in the soil by the accumulation of rainfall in the winter season and the potential for capillary rise of shallow groundwaters is crucial for adjusting irrigation to vine water requirements.
- ItemOrganizational Commitment and Burnout During the COVID-19 Pandemic: A Comparative Analysis in the United States and New Zealand(Taylor and Francis Group on behalf of the World Communication Association, 2024-06-17) Croucher SM; Rocker K; Singh R; Feekery A; Ashwell D; Green M; Murray N; Anderson KThis study examined the link between organizational commitment (OC) and burnout during COVID-19 in New Zealand and the United States. Results revealed OC and burnout differed between the U.S. and New Zealand. In addition, the correlations between OC and the dimensions of burnout differed between the nations, particularly on issues linked with emotional exhaustion and personal accomplishment. These results point to the influence of lockdowns and other physical limitations on burnout and commitment in organizations. Theoretical and practical implications are discussed, as well as areas for future research.
- ItemQuantification of denitrification rate in shallow groundwater using the single-well, push-pull test technique(Elsevier BV, Amsterdam, 2025-02) Rivas A; Singh R; Horne D; Roygard J; Matthews A; Hedley MDenitrification has been identified as a significant nitrate attenuation process in groundwater systems. Hence, accurate quantification of denitrification rates is consequently important for the better understanding and assessment of nitrate contamination of groundwater systems. There are, however, few studies that have investigated quantification of shallow groundwater denitrification rates using different analytical approaches or assuming different kinetic reaction models. In this study, we assessed different analytical approaches (reactant versus product) and kinetic reaction (zero-order and first-order) models analysing observations from a single-well, push-pull tests to quantify denitrification rates in shallow groundwater at two sites in the Manawatū River catchment, Lower North Island of New Zealand. Shallow groundwater denitrification rates analysed using the measurements of denitrification reactant (nitrate reduction) and zero-order kinetic models were quantified at 0.42-1.07 mg N L-1 h-1 and 0.05-0.12 mg N L-1 h-1 at the Palmerston North (PNR) and Woodville (WDV) sites, respectively. However, using first-order kinetic models, the denitrification rates were quantified at 0.03-0.09 h-1 and 0.002-0.012 h-1 at the PNR and WDV sites, respectively. These denitrification rates based on the measurements of denitrification reactant (nitrate reduction) were quantified significantly higher (6 to 60 times) than the rates estimated using the measurements of denitrification product (nitrous oxide production). However, the denitrification rate quantified based on the nitrate reduction may provide representative value of denitrification characteristics of shallow groundwater systems. This is more so when lacking practical methods to quantify all nitrogen species (i.e., total N, organic N, nitrite, nitrate, ammoniacal N, nitrous oxide, nitric oxide, and nitrogen gas) in a push-pull test. While estimates of denitrification rates also differed depending on the kinetic model used, both a zero-order and a first-order model appear to be valid to analyse and estimate denitrification rate from push-pull tests. However, a discrepancy in estimates of denitrification rates using either reactant or product and using zero- or first-order kinetics models may have implications in assessment of nitrate transport and transformation in groundwater systems. This necessitates further research and analysis for appropriate measurements and representation of spatial and temporal variability in denitrification characteristics of the shallow groundwater system.
- ItemThe effects of pastoral hill country natural landscape features and land management practices on nitrate losses and its potential attenuation for improved water quality(Global Initiative of Sustainable Agriculture and Environment and John Wiley and Sons Australia, Ltd, 2024-03-22) Chibuike G; Singh R; Burkitt LPastoral farming on hill country landscapes influences nitrogen (N) dynamics and its losses to freshwater. This study reviewed the current literature identifying key effects of pastoral hill country landscape features and land management practices on nitrate losses to receiving waters. The review also highlighted the potential effects of inherent landscape features on nitrate attenuation pathways for better water quality outcomes. Intensive land use activities involving high rates of fertiliser application, higher stocking rates and cattle grazing, relative to sheep grazing, are more likely to increase nitrate loss, especially on lower slopes. However, soils with a high carbon (C) storage capacity such as allophanic soils potentially limit nitrate loss via denitrification in subsoil layers. Hill country seepage wetlands also offer an opportunity to attenuate nitrate loss, though their efficacy is largely impacted by hydrological variations in their inflows and outflows. By enhancing the natural nitrate attenuation capacity of seepage wetlands, mapping and strategic use of high subsoil denitrification potential, effective riparian management, efficient fertiliser and grazing practices and the incorporation of these farm management strategies into Freshwater Farm Plans (FWFPs), wider environmental and farm productivity/profitability goals, including improved water quality, would be achieved on pastoral hill country landscapes.
- ItemThe Water Footprint of Pastoral Dairy Farming: The Effect of Water Footprint Methods, Data Sources and Spatial Scale(MDPI (Basel, Switzerland), 2024-02) Higham CD; Singh R; Horne DJ; Gerbens-Leenes WThe water footprint of pastoral dairy milk production was assessed by analysing water use at 28 irrigated and 60 non-irrigated ‘rain-fed’ pastoral dairy farms in three regions of New Zealand. Two water footprint methods, the WFN-based blue water footprint impact index (WFIIblue) and the Available WAter REmaining (AWARE) water scarcity footprint (WFAWARE), were evaluated using different sets of global or local data sources, different rates of environmental flow requirements, and the regional or catchment scale of the analysis. A majority (~99%) of the consumptive water footprint of a unit of pastoral dairy milk production (L/kg of fat- and protein-corrected milk) was quantified as being associated with green and blue water consumption via evapotranspiration for pasture and feed used at the studied dairy farms. The quantified WFIIblue (-) and WFAWARE (m3 world eq./kg of FPCM) indices ranked in a similar order (from lowest to highest) regarding the water scarcity footprint impact associated with pastoral dairy milk production across the study regions and catchments. However, use of the global or local data sets significantly affected the quantification and comparative rankings of the WFIIblue and WFAWARE values. Compared to the local data sets, using the global data sets resulted in significant under- or overestimation of the WFIIblue and WFAWARE values across the study regions and catchments. A catchment-scale analysis using locally available data sets and calibrated models is recommended to robustly assess water consumption and its associated water scarcity impact due to pastoral dairy milk production in local catchments.
- ItemWater Footprints of Dairy Milk Processing Industry: A Case Study of Punjab (India)(MDPI (Basel, Switzerland), 2024-02) Sharma H; Singh PK; Kaur I; Singh R; Teodosiu CA robust assessment of water used in agriculture, including livestock production systems and supply chains, is critical to inform diversification and the development of productivity and sustainable food production systems. This paper presents a detailed analysis of water used and consumed in nine dairy milk processing plants spread across Punjab, India’s leading dairy milk-producing state. Over the five years (2015–2019), the direct water use (DWU) was quantified at 3.31 L of groundwater per kg of milk processed. Only about 26% of the direct water used was consumed, including evaporative losses in various milk processing operations, while the remaining 74% was returned as effluent discharges. The average total water footprint (TWF), accounting for both direct and indirect water consumption, was quantified at 9.0 L of water per kg of milk processed. The majority share (~89%) of the total water footprint was contributed by the indirect water footprint associated with the consumption of electricity (energy) in dairy milk processing activities. The plant’s milk processing capacity and processing products mix also affected significant seasonal and annual variations in the direct and indirect water footprints of dairy milk processing. The analysis also found an inverse relationship between the average total water footprint and the average monthly amount of milk processed in the study plants. Therefore, efforts to reduce the indirect water footprint (associated with energy consumption), the treatment and recycling of effluent discharges, and the optimization of milk processing capacity, the dairy processing product mix, and the locations of dairy processing plants are expected to help reduce the water footprint of dairy processing in the state.
