Sandeep Kumar

• PhD
• Professor (Assistant) at South Dakota State University

Integrated crop-livestock systems (ICLS) can mitigate the impacts of cropping intensification by improving soil organic carbon (SOC) and associated hydro-physical properties. This study was conducted on three on-farm long-term (≥30 years) sites (Site 1, 2, and 3) and one short-term (4 years) experimental site (Site 4) to compare the SOC and hydro-p...

Prairie cordgrass (PCG) is a perennial crop which has the potential for biofuel production under marginal lands. The intercropping of a perennial legume, kura clover (KC) with PCG can reduce the use of chemical fertilizer while maintaining the soil hydro-physical conditions. The objective of this study was to compare the soil hydro-physical propert...

Using manure appropriately may enhance organic carbon and hydro‐physical properties while avoiding the negative impact on the environment. However, how manure impacts soils, especially at lower depths, is still not well studied. Therefore, the objective of this study was to assess the impact of different manure and inorganic fertilizer application...

Soil hydro-physical properties and pore characteristics are crucial for crop production as they determine water, air, and nutrients transfer. Long-term tillage and crop rotation studies provide valuable insights into the effects of management practices on various soil properties. Because of the inherent differences between the surface and sub-surfa...

Long-term fertilizer application in row crops may influence soil pore characteristics, thereby impacting soil aggregation and structure. Therefore, understanding the influences on soil pore characteristics is useful for adopting suitable conservation practices. However, the impact of cattle manure and inorganic fertilizer application at varied rate...

Agricultural management practices tend to influence soil structure stabilization, mediating many physical, chemical, and biological processes in soils. Therefore, understanding the long‐term effects of management practices on various soil health indicators is crucial to develop sustainable agricultural practices. This study aimed to assess the long...

Dedicated bioenergy crops such as switchgrass ( Panicum virgatum L.) can be grown on marginally productive lands and positively influence soil properties. However, nitrogen management, and landscape can alter soil structural attributes under bioenergy crop production. This study investigated the impacts of long-term nitrogen fertilization (0-N, 0 k...

Using manure appropriately can enhance organic carbon, and hydro-physical properties without negatively impacting the environment. However, how manure impacts soils, especially at deeper depths, is still not well studied. Therefore, the objective of this study was to assess the impact of different manure and inorganic fertilizer application rates o...

Long-term manure and inorganic fertilizer application in row crops may significantly influence soil pore characteristics, thereby impacting soil aggregation and structure. Understanding the influence of such soil amendments on soil pore characteristics is useful to develop proper conservation practices. However, there is limited information on the...

The study of solute transport in soil and porous media is critically important to develop management methods to mitigate soil and ground water pollution. Potential pollutants include agrochemicals as well as waste products from petroleum, nuclear, and chemical industries. These pollutants are often transported to groundwater via leaching through th...

An integrated crop–livestock system (ICL) can help with enhancing soil quality and crop productivity, ultimately increasing farm income. Field experiments that evaluated the impact of cover crops (CCs) and grazing on crop productivity have shown mixed results primarily because of a relatively short duration of the crop–livestock system. Dynamic cro...

Black walnut (Juglans nigra) and honeylocust (Gleditsia triacanthos) have gained particular interest for use in silvopastures and other temperate agroforestry systems. However, measures of soil health indicators in these deciduous hardwood silvopastures over time have received limited attention. This study assessed soil health indicators in 25-year...

Winter cover crop (CC) has the potential for improving soil physical condition; however, both improvement and depletion of soil water storage because of CC were reported depending on the soil depth and the rainfall received in a growing season. The present study used sensors to measure the soil moisture content (cm³ cm⁻³) and soil water potential (...

Cover crops (CCs) and grazing play critical roles in the successful implementation of integrated crop-livestock systems (ICLSs) because they can have a direct impact on soil functions. The present study was conducted to assess the short-term impacts of CCs and grazing on soil physical and hydrological properties. Two sites (Northern-Brookings and N...

No-till (NT) is a sustainable alternative to conventional-till (CT), however, the impacts of NT and its duration on the depth distribution of soil organic carbon (SOC), physical and hydrological parameters are less studied. Therefore, the objective of this study was to evaluate the changes in soil hydro-physical properties and X-ray computed tomogr...

Understanding historical crop water use (CWU) dynamics is important to improve land and water management. In this study, well-validated (coefficient of determination = 0.91, percent bias = 4%, and percent root mean square error = 11.8%) Landsat-based actual evapotranspiration (ETa) time-series estimations were used to (1) assess summer season CWU (...

Switchgrass (Panicum virgatum L.) is a promising feedstock for bioenergy and bioproducts; however, its inherent variability in chemical attributes creates challenges for uniform conversion efficiencies and product quality. It is necessary to understand the range of variation and factors (i.e., field management, environmental) influencing chemical a...

Soil carbon dioxide (CO 2 ) emissions from the field of corn ( Zea mays L.) play an important role in global warming. This study investigated temporal variability of soil CO 2 fluxes ( R s ) with soil temperature ( T s ) and moisture ( θ ) and built DAYCENT models for predicting future impacts of climate changes on R s using the measured high-frequ...

Manure nutrient management can affect soil carbon (C) and nitrogen (N) fractions. The objective of this study was to determine the effects of long term manure and mineral fertilizer applications on C and N fractions. This study was conducted for 11 years under corn and soybean rotation. The study rates included low manure (LM (4,194 kg ha−1), based...

Integrated crop–livestock (ICL) production enhances diversification and provides ecosystem benefits by improving nutrient cycling and energy efficiency, thus, increasing overall farm productivity. However, a detailed study is needed to understand the influence of crop diversification and grazing animals on soil aggregation and associated carbon (C)...

Context No-tillage (NT) has been gaining popularity over the conventional tillage (CT) for agricultural sustainability. Field experiments conducted worldwide to compare crop production under NT vs CT systems are generally site specific and expensive to maintain over longer duration. To overcome this gap, process-based models have been used to simul...

This study highlights the usefulness of X-ray CT in quantifying soil pore characteristics Based on the results, the study recommends manure over fertilizer application to improve pore characteristics. In this study, long-term manure application increased SOC and improved soil pore characteristics over fertilizer

A major cause of soil productivity loss under intensive farming is attributed to depletion in soil carbon stock and changes in soil water holding capacities. The use of organic manure in agricultural production exemplifies a strategy for improving soil physical conditions to increase soil carbon and plant available water in the soil. This study obs...

Context Labile soil C and N fractions are strongly influenced by agricultural management practices. Aims This study was conducted on three long-term (≥30 years) on-farm sites (sites 1–3), and one short-term (3 years) experimental site (site 4) to evaluate the impacts of integrated crop–livestock system (ICLS) on labile C and N fractions and β-gluc...

Winter rye (Secale cereale L.) is an important cover crop (CC) in the northern Great Plains (NGP), yet concerns over its establishment under the variable weather conditions of this region are an important limitation for its widespread adoption. This study evaluated the impacts of no‐till corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation...

Soil amendments can help reduce greenhouse gas (GHG) emissions and increase soil organic carbon (SOC) and crop yield. However, most biochar studies have been conducted on single soil type under controlled conditions. To address this limitation, the aim of this research was to investigate how field biochar and manure applications affect soil quality...

Conventional-till (CT) practices can reduce soil organic matter (SOM) and microbial activity and increase soil erosion and compaction. In contrast, no-till (NT) has emerged as a viable option for protecting the soil surface against erosion and degradation. The NT has a lot of advantages such as reduced equipment costs, runoff, and erosion, increase...

Crop yield and economic profitability, both highly dependent on local crop management, soil characteristics, and weather conditions, are among the most influential factors to consider when considering a cropping system. The objective of this study was to compare the economic returns of three different 4‐yr diverse crop rotations with that of a 2‐yr...

Integrated crop-livestock systems (ICLS) can be productive, sustainable, and climate-resilient agricultural systems compared to specialized and intensive systems. This review explores the beneficial traits and contributions of ICLS to food security, social and economic benefits, and resilience, and proposes strategies to adopt ICLSs in low-, medium...

Integrated crop–livestock (ICL) systems are diverse production systems that can improve resource utilization through spatially or temporally rotating land among crop, livestock, and pasture uses. However, research on whether the enhanced resource utilization translates to greater crop productivity is still warranted. A field experiment was initiate...

This study was conducted to determine the effect of different green manure treatments on net GWP and GHGI in upland soil. Barley (B), hairy vetch (HV), and a barley/hairy vetch mixture (BHV) were sown on an upland soil on November 4, 2017 and October 24, 2018. The aboveground biomass of these green manures was incorporated into soil on June 1, 2018...

Introducing cover crops (CC) in annual cropping systems can promote nutrient cycling and improve soil health. However, impacts of CC on soil health indicators vary and depend on the duration of CC, cropping systems, and other environmental conditions. We performed an on-farm assessment of cover cropping impacts on soil health indicators including C...

Prairie cordgrass (PCG) (Spartina pectinata Link) has been the focus of much scientific attention recently for use in biofuel applications, as it grows well on marginal lands that are unsuitable for row crops. This study investigated how the intercropping of kura clover (KC) (Trifolium ambiguum M. Bieb) with PCG for 8 yr affects soil carbon (C) and...

Enhancing crop production and productivity, less energy input and reducing soil erosion make no-till (NT) an add-on choice over the conventional till (CT) system. The present study was conducted at three different locations (Beresford, Langford, and Woonsocket) to compare the natural (undisturbed) ecosystem (NE) with the tilled (CT) and no-tilled (...

Land use land cover (LULC) and climate are the determinant factors for the soil water balance. The combined effect of LULC and climate change is of great importance for effective water resources planning and management. This study assessed the hydrological impact of long‐term implementation of integrated crop‐livestock (ICL) system with the project...

The aims of this study were to determine type and application rate of composted animal manure to optimize sweet potato yield relative to N2O emissions from upland soils. To this end, the study was conducted on upland soils amended with different types and rates of composted animal manure and located at two geographically different regions of South...

Carinata (Brassica carinata A. Braun), a non‐food oilseed crop and an alternative bio‐jet fuel feedstock, has received attention for its potential as a low‐input option for production in the semi‐arid region of the Northern Great Plains of the USA. Research addressing the impacts of nitrogen (N) and sulfur (S) fertilizers on soils and greenhouse ga...

Soil porosity estimated conventionally cannot provide the spatial distribution and geometrical properties of pore networks. This on‐farm study assessed the impacts of grassland–cropland conversion on soil pore characteristics. This study aimed to quantify the microscale changes in pores near the soil surface (0–10 cm) under grasslands converted to...

Manure application can enhance soil fertility and crop yield; however, knowledge of optimum application rates of manure is needed to prevent negative impacts on soils and environment. This study was aimed to compare the long-term effects of manure and inorganic fertilizer application at different rates on soil nutrients, aggregate stability, organi...

Reliable information on water use and availability at basin and field scales are important to ensure the optimized constructive uses of available water resources. This study was conducted with the specific objective to estimate Landsat-based actual evapotranspiration (ETa) using the Operational Simplified Surface Energy Balance (SSEBop) model acros...

Increasing crop diversity has been highly recommended because of its environmental and economic benefits. However, the impacts of crop diversity on soil properties are not well documented. Thus, the present study was conducted to assess the impacts of crop diversity on selected soil quality indicators. The cropping systems investigated here include...

No-till (NT) management can improve soil aggregate formation and stability, porosity, and organic carbon (SOC) through the addition of crop residues and less soil disturbance. However, conventional-till (CT) can deteriorate soil structure and cause loss of SOC. This study aimed to quantify the impacts of long-term (NT L) and short-term NT (NT S) on...

Integrated crop-livestock system (ICLS) has the potential to enhance soils quality by improving soil chemical, physical, and biological parameters especially soil organic carbon. objective of this study was to assess the impact of low and high stocking rates (number of animal per hectare) under ICLS on soil quality parameters at the farm scale and...

In the northern Great Plains (NGP), wheat is the primary grain commodity. There is a need for the NGP to have a detailed analysis of environmental impacts for wheat‐based agricultural production systems to better understand regional agroecosystems. This article provides a cradle‐to‐field gate life cycle assessment (LCA) for NGP dryland wheat (Triti...

Carinata (Brassica carinata A. Braun), a non‐food oilseed and an alternative biofuel feedstock, has received attention for its potential as a low‐input option for production in the semi‐arid regions of the Northern Great Plains (NGP). This study was conducted to (a) determine the economic optimum N and S fertilization rates and (b) determine the in...

This study aimed to determine cadmium (Cd) accumulation in arable soil, changes in Cd extractability and relevant soil properties, and Cd uptake by rice plants after long-term (50 years) application of phosphate (P) fertilizer and compost. A long-term field experiment was performed with rice crops from 1967 to 2016. Treatments included nitrogen and...

The intensive use of mineral fertilizers to achieve high crop yield has led to soil degradation and poor soil health. Thus, manure application as an alternative to mineral fertilizers can be an effective fertilization strategy to sustain soil health and biodiversity. This study aims to assess the impacts of long-term manure and mineral fertilizers...

Integrated crop-livestock (ICL) system that include livestock grazing of crop residue and/or cover crops is an agricultural practice that manage crops and livestock on a single farm. Integrated crop-livestock system can provide opportunities to restore ecological services and interactions among different land-use systems to enhance agricultural eco...

This study examined the effect of crop rotations and winter cover crops (CCs) on near‐surface pore characteristics of a silty clay loam soil in a 27‐yr no‐till field experiment. The crop rotation treatments included a 2‐yr corn (Zea mays L.)–soybean [Glycine max L. (Merr.)] (CS) rotation and a 4‐yr corn–soybean–oat (Avena sativa L.)–winter wheat (T...

Consumer demand for sustainably produced agricultural products is increasing. One approach that can be used to evaluate and compare product sustainability is to conduct a life cycle analysis (LCA). The term LCA is broadly used to describe a suite of analytical resources and standardized methods. Life cycle analyses are a transdisciplinary tool whic...

Prairie cordgrass (PCG) (Spartina pectinata Link) has a high tolerance to soil salinity and waterlogging, therefore, it can thrive on marginal lands. Optimizing the nitrogen (N) input is crucial to achieving desirable biomass production of PCG without negatively impacting the environment. Thus, this study was based on the hypothesis that the use of...

Integrated crop-livestock system (ICLS) is an alternative that can help in intensifying food production while benefiting the environment. However, the assessments of the impacts of ICLS on the soil and economic benefits relative to specific environments in South Dakota are still lacking. This study was to assess the effects of ICLS on soil health a...

An integrated crop–livestock system (ICLS), when managed properly, can help in mitigating soil surface greenhouse gas (GHG) fluxes, especially carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). However, the impacts of an ICLS on GHG fluxes are poorly understood. The present study was conducted at two sites (northern Brookings [Brookings‐...

Tillage activities play a crucial role in impacting soil physical and chemical properties, which in turn alter soil biochemical activities and microbial community structure. In this study, responses of soil biochemical activities and microbial community structure to short‐term (NT S , <5 years) and long‐term (NT L , >10 years) no‐till (NT) systems...

Biochar and manure application can modify soil microbial community structure and enhance biochemical activities. However, the studies about the influence of biochar and manure on the microbial communities on different geomorphological landforms (depositional and eroded landscapes) are scarce. In this study, we investigated the responses of soil bio...

Prairie cordgrass (Spartina pectinata L.) (PCG) has the potential to replace significant amounts of fossil fuels. However, its associated greenhouse gas (GHG) emissions under different rates of nitrogen (N) fertilizer has not been well studied. The use of legumes as a mixture with PCG can provide extra N to the crop, thus reducing need for N fertil...

Although past research suggested that biochar has the potential to mitigate the emission of greenhouse gases (GHGs), studies investigating how biochar affects GHG emissions from different soil types under field conditions are limited. Furthermore, limited knowledge exists on how interactions between biochar and manure affect GHG emissions from diff...

Optimizing the use of N fertilization is the major factor for establishing perennial grasses to enhance the biomass production and soil health under marginally yielding croplands. A study was conducted to investigate the influence of N fertilization and intercropping of kura clover (Trifolium ambiguum M. Bieb) (KC) with prairie cordgrass (PCG) (Spa...

Biochar is known to ameliorate soil fertility and increase crop yield; however, information regarding its effects on soil chemical and biological properties remains limited. The experiment was conducted to study the short-term impacts of different types of biochar on soil C fractions, enzyme activities, and microbial community structure at depositi...

Soil carbon stability is associated with soil microbial ecology due to the role of microbial activities in carbon cycling and soil health. Soil microbial attacks cause decomposition and mineralization of organic matter where soil aggregates are broken down. As an important component of carbon and nitrogen cycling, soil organic matter is an often-re...

Diversification of crop species and minimum mechanical soil disturbance are the interlinked principles of conservation agriculture that are beneficial in improving soil physical and hydrological properties, and hence crop productivity. The present study was conducted to assess the long-term impacts of crop rotational diversity and tillage on soil w...

Camelina (Camelina sativa L.) and carinata (Brassica carinata) are nonfood oilseeds known for their potential as a promising biofuel feedstock; however, their associated greenhouse gas (GHG) emissions under different rates of nitrogen (N) fertilizer has not been well studied. This study was conducted to evaluate the impacts of N fertilization rates...

Integrated crop–livestock systems (ICLSs) can help increase food production while benefiting soils and the environment. This review summarizes recent impacts of ICLSs on crop and livestock production and rural economics and discusses lessons learned in the northern Great Plains (NGP). Research on ICLS conducted in the NGP indicates that the crop re...

Core Ideas Manure improved soil hydrological properties in comparison with those of inorganic fertilizer and control. Manure decreased soil bulk density but increased C stocks and water retention compared with inorganic fertilizer. The higher rate of manure decreased soil bulk density and increased C stocks compared with lower rates of manure and i...

Switchgrass (Panicum virgatum L.) has been recognized as a potential bioenergy feedstock due to its high yield potential and benefits to the environment. However, little is known about the impacts of nitrogen fertilization and landscape position on soil properties in switchgrass fields at multiple locations in the USA. The objective of this study w...

Core Ideas We studied the impact of three rotations and two tillage systems on soil biological health after 25 yr. A significant rotation × tillage interaction was found for microbial biomass C and N, hot‐water‐extractable C, and urease and β‐glucosidase activity. Adoption of no‐till and diversified crops improved these soil health properties. Cro...

Manure impacts labile pools of soil organic carbon (SOC) and nitrogen (N) which can influence soil microbial composition (MCC) and enzyme activities, and hence soil health. The present study was conducted to investigate the impacts of long-term dairy manure and inorganic fertilizers (INF) on soil carbon (C) as well as nitrogen (N) fractions, enzyme...

A recent conversion of the grasslands to cropland degrading the soil quality (SQ), and impacting the soil erosion and crop productivity in the West Corn Belt (WCB) of the USA. The current study was conducted to estimate the spatial distribution of soil erosion at Big Sioux River (BSR) watershed scale using the Geographical Information System (GIS)-...

Integrated crop-livestock (ICL) system is beneficial in enhancing soil organic carbon and nutrient cycling. However, the benefits of the ICL system on mitigation of GHG emissions are poorly understood. Thus, the present study was initiated in 2011 to assess the effect of crop rotation diversity and grazing managed under the ICL system on GHG emissi...

Switchgrass (Panicum virgatum L.) has the potential to recover the soil hydrological properties of marginal lands. Nitrogen (N) and landscape position are the key factors in impacting these soil properties under switchgrass. The specific objective of this study was to investigate the responses of N rate (low, 0 kg N ha⁻¹ and high, 112 kg N ha⁻¹) an...

Core Ideas Brassica carinata is a new crop in the Northern Great Plains. Best management practices including N fertilizer recommendations should be developed. Seed yield and oil yield were optimized at 84 kg ha–1 of applied N fertilizer. Seed oil concentration decreased linearly at a rate of 0.26 g kg–1 for every 1 kg ha–1 increase in N rate. Econo...

Core Ideas Nitrogen rate did not affect soil properties for Oklahoma, South Dakota, and Virginia. Landscape position affected soil properties under higher slope. Nitrogen rate affected root N, surface area, and weight for the total profile. Landscape position affected the root C and N. Switchgrass roots can increase C accumulation and reduce risk o...

Geospatial computation, data transformation to a relevant statistical software, and step-wise quantitative performance assessment can be cumbersome, especially when considering that the entire modelling procedure is repeatedly interrupted by several input/output steps, and the self-consistency and self-adaptive response to the modelled data and the...

Switchgrass (Panicum virgatum L.) is usually grown on marginal land for biofuel system, in which nitrogen (N) is an essential management practice, and landscape position is a key topographical factor in impacting the production. However, limited information is available regarding how the N application and landscape positions affect soil microbial c...

Diversification within a cropping system together with no-till (NT) soil management can help to improve soil organic carbon (SOC). The present study was conducted to assess the impacts of crop diversity through crop rotations on SOC and other selected soil properties. The long-term experimental sites were located in Beresford and Brookings, South D...

Core Ideas Residue returned increased organic carbon and reduced bulk density compared to residue not returned. Residue returned increased water retention and infiltration compared to residue not returned. Residue returned and cover crop increased soil volumetric water content and water storage. Cover crop reduced bulk density and increased water i...

Excessive crop residue returned to the soil hinders farm operations, but residue removal can affect soil quality. In contrast, cover cropping can return additional residue to the soil and improve soils and environmental quality compared with no cover cropping. Residue and cover crop impacts on soil surface greenhouses gas (GHG) emissions are undete...

Core Ideas Long‐term annual application of manure maintained the soil pH but inorganic fertilizer decreased it. Manure application increased soil organic carbon (SOC) and total nitrogen (TN). Higher manure rate helps in improving the water stable aggregates compared to inorganic fertilizer at 0‐ to 10‐cm depth. Manure enhances soil fertility and c...

Removing plant residue from soil has been shown to have an adverse effect on soil health; however, the addition of cover crops may help mitigate these impacts. This study was conducted to assess the effect of incorporating cover crops on soil health with varying removal rates of corn (Zea mays L.) residues. Corn was grown in rotation with soybean (...

Switchgrass (Panicum virgatum L.) cultivation for bioenergy has the potential to improve soil properties. However, little is known about the changes in soil properties for first few years of switchgrass establishment. The objectives of this study were to evaluate the impacts of nitrogen fertilization rate (N rate) and landscape position on soil pro...

Runoff from grazing pasture lands can impact water quality in receiving streams if not well managed. Management consists of conservation practices to reduce runoff and pollutants transport. Simulation models have been effectively used to design and implement these conservation practices. The Agricultural Policy Environmental Extender (APEX), a proc...

This study was conducted to investigate the impacts of dairy manure and inorganic fertilizer on soil surface greenhouse gases (GHG) [carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4)] fluxes from soils managed under corn (Zea mays L.)-soybean (Glycine max L.) rotation. The experiment was established on a silty loam soil, and the treatment...

Switchgrass (Panicum virgatum L.) production has the potential to improve soils and the environment. However, little is known about the long-term future assessment of soils and environmental impacts associated with switchgrass production. In this study, soil organic carbon (SOC), soil nitrate (NO3⁻), water-filled pore space (WFPS), carbon dioxide (...

The Rocky Mountains in North America are comprised of headwater snow catchments that provide sustained seasonal flow downstream. Changes in streamflow over the last half century in these basins may be associated with changing climate with increased temperature and variable precipitation, shifting seasonal hydrology. We investigated potential change...

Biochar has been proposed as a management strategy to improve soil physical and chemical properties and climate change mitigation. However, the effect of biochar on soil microbial activity is highly uncertain and few data from field experiments are available. Therefore, the objective of our study was to investigate the influence of biochar and manu...

Addition of biochar to improve soil hydrological properties has been evaluated by many researchers. However, most of the studies were conducted in controlled labs or greenhouses conditions. The present study was conducted in the field with the specific objective to evaluate the impact of biochar and manure on hydrological properties of soils at ero...

Th e purpose of this study was to assess the changes in switchgrass (Panicum virgatum L.) biomass quality as aff ected by N rate, harvest time, and storage. Th is research was conducted near Bristol, SD, in 2010 and 2011. Treatments included three N rates (0, 56, and 112 kg N ha–1) applied annually and each N rate replicated four times. After a kil...

Calibration and validation of process based hydrological models are two major processes while simulating the water balance components of watershed systems. However, these processes need a better understanding of the parameters which influence hydrologic processes within the system. In this study, we used SWAT model to simulate the stream flow for S...

The addition of biochar to improve soil hydrological properties has been evaluated by many researchers. However, most studies have been conducted in controlled laboratories or greenhouses. This study was conducted in the field with the objective of evaluating the impact of biochar on the hydrological properties of soils at eroded and depositional l...