Soil organic matter and microbial community responses to semiarid croplands and grasslands management

Ghimire, Rajan; Thapa, Vesh R.; Cano, Amanda; Acosta-Martínez, Verónica

doi:10.1016/j.apsoil.2019.05.002

Cited by 44 publications

(22 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is not surprising that decomposition rate increases with increasing disturbance and annual cropping compared to perennial grasses. Previous studies show a positive relationship between labile SOC pools, CO 2 -C production, and SOC sequestration ( Ahlering, Fargione & Parton, 2016 ; Ghimire et al, 2019 ; Ghimire, Machado & Bista, 2019 ; Six, Elliott & Paustian, 2000 ). However, we expected a lower decomposition rate in dryland cropping systems because of low biomass recycling in dryland cropping systems.…”

Section: Discussionmentioning

confidence: 84%

“…The SOC under perennial grasses also increases from a higher root: shoot ratio and low decomposition rate of roots from perennial grasses than from annual crops ( Yang et al, 2019 ). Perennial grasses also increase microbial biomass, thereby contributing to more SOC and N accumulation in grasslands compared to croplands ( Ghimire et al, 2019 ). Our previous study shows two- to six-times greater biomass C inputs in grassland than in cropland soils ( Ghimire, Machado & Rhinhart, 2015 ).…”

Section: Discussionmentioning

confidence: 99%

“…Grassland restoration could be another strategy to increase SOC storage in agroecosystems transitioning from irrigated to dryland management. A recent study documented up to a 37% increase in SOC with grassland restoration (∼50 years), which was not significantly different from SOC in a lightly grazed native pasture under dryland condition ( Ghimire et al, 2019 ). The increase in SOC and nutrients with grassland restoration in the previously cultivated soils have also been documented from other semiarid regions of the world, the magnitude of increase varying with management practices and environment ( Liu et al, 2017 ; Yang et al, 2019 ).…”

Section: Introductionmentioning

confidence: 87%

“…Although physical, chemical, and biological transformation processes convert plant residues into organic matter, the biologically active fraction of SOC could be affected by management changes more rapidly than other fractions ( Lehmann & Kleber, 2015 ), while the soil disturbance and long-fallow periods can lead to the rapid loss of biologically active SOC and N fractions conservation systems that reduce tillage and increase cropping intensity and diversity can improve SOC storage and nutrient cycling ( Ghimire, Machado & Bista, 2019 ). The conservation systems may be important for the Southern High Plains agroecosystems, where hot, dry environment and intermittent irrigation favors rapid mineralization of organic matter and limits biomass C inputs, as well as microbial activities ( Cano et al, 2018 ; Ghimire et al, 2019 ). Improved understanding of management practices that affect various SOC and N fractions will help in designing sustainable cropping systems in semiarid regions in the time of uncertainty due to decreasing irrigation capacity.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Soil organic matter dynamics in semiarid agroecosystems transitioning to dryland

Ghimire

Khanal

2020

PeerJ

Self Cite

View full text Add to dashboard Cite

Recent interest in improving soil health and agricultural sustainability recognizes the value of soil organic carbon (SOC) sequestration and nutrient cycling. The main goal of this study was to evaluate the response of various SOC and nitrogen (N) components in semiarid cropping systems transitioning from limited-irrigation to dryland and a restored grassland in the Southern High Plains of USA. Cropping systems evaluated include dryland winter wheat (Triticum aestivum L.)–sorghum (Sorghum bicolor L.)–fallow with conventional tillage (DLCTF) and no-tillage (DLNTF), limited-irrigation winter wheat–sorghum–fallow with no-tillage and cover cropping (LINTC) and no-tillage fallow (LINTF), and an undisturbed grassland (NG). Soil samples were collected from 0–15 cm and 15–30 cm depths and analyzed for SOC, total N, inorganic N, and soil microbial biomass carbon (SMBC) contents. The CO2 and N2O release during a eight-weeks long laboratory incubation were also analyzed. Results show 14% and 13% reduction in SOC and total N from 0–30 cm depth with the transition from limited-irrigation to dryland cropping systems while 51% more SOC and 41% more total N with the transition to grassland. The SMBC was 42% less in dryland cropping systems and 100% more in NG than the limited-irrigation cropping systems. However, the grassland was N limited, with 93% less inorganic N in NG compared to only 11% less in dryland cropping systems than in limited-irrigation cropping systems. The microbial respiration measured as CO2-C was highest in NG, followed by limited-irrigation and dryland cropping systems. The N2O-N release showed the lowest rate of N loss from dryland cropping systems, followed by NG and limited-irrigation cropping systems. This study demonstrated loss of SOC and N in agroecosystems transitioned to dryland crop-fallow systems, with greater magnitude of change observed in the biologically active fraction of soil organic matter. Grassland restoration could be an important strategy to increase SOC and nutrients in hot, dry, semiarid agroecosystems transitioning to dryland.

show abstract

Section: Discussionmentioning

confidence: 84%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 87%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Soil organic matter dynamics in semiarid agroecosystems transitioning to dryland

Ghimire

Khanal

2020

PeerJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…We collected soil samples only from the center of grass strips, and the edge effects are unknown. Previous studies comparing grasslands and croplands reveal N limitation in grassland, but they had higher PCM and total soil C than croplands [16,20,37]. Grasses often have deeper and denser root systems than annual crops, which contributes to greater root-derived C under grasses than under annual crops [38].…”

Section: Discussionmentioning

confidence: 94%

Grass Buffer Strips Improve Soil Health and Mitigate Greenhouse Gas Emissions in Center-Pivot Irrigated Cropping Systems

et al. 2020

Self Cite

View full text Add to dashboard Cite

Declining water resources and soil degradation have significantly affected agricultural sustainability across the world. In the southern High Plains of USA, buffer strips of perennial grasses alternating with cultivated corn strips were introduced in center-pivot irrigated crop fields to increase agronomic production and ecosystem services. A study was conducted to evaluate soil carbon (C) and nitrogen (N) dynamics, greenhouse gas (GHG) emissions, and soil health benefits of integrating circular grass buffer strips in the center-pivot irrigated corn production system. Multiple parameters were assessed in the grass buffer strips, and at distances of 1.52, 4.57, and 9.14 m away from the edges of grass strips in corn strips. While grasses in the buffer strips depleted N compared to corn strips, potential C mineralization (PCM) was 52.5% to 99.9% more in grass strips than in corn strips. Soil microbial biomass C (MBC) content was 36.7% to 52.5% greater in grass strips than in corn strips. Grass buffer also reduced carbon dioxide (CO2) and nitrous oxide (N2O) emissions from corn strips. Grass buffer strips can improve soil health and sustainability in center-pivot irrigated cropping systems by increasing soil C components and reducing GHG emissions.

show abstract

Cropping management in a livestock–pasture–crop integration modifies microbial communities, activity, and soil health score

et al. 2022

View full text Add to dashboard Cite

Understanding indicators of soil health is crucial for developing agricultural systems that are sustainable and climate resilient. Labile soil carbon (C), microbial properties, and nutrient status are all incorporated into the Haney Soil Health Tool with the goal of summarizing several indicators into one index. Monthly soil samples from an integrated crop–livestock system in Central Texas were collected from 2017 to 2019. Fields represented a range of management practices, including cover crops, no‐till, rotational grazing, and a native prairie remnant. Soil samples were analyzed for total C, water‐soluble C, macro‐ and micronutrient content and bioavailability, and phospholipid fatty acids (PLFAs). Microbial activity was determined via a 24‐h CO2 incubation. Soil health score, C, and PLFAs were well correlated with each other. The greatest total PLFA (219.5 nmol g–1 soil) and organic C (54.3 g kg–1 soil) were found in the native prairie, and the lowest were found in the unfertilized continuous‐corn system (60.5 nmol PLFAs g–1 soil and 24.0 g organic C kg–1 soil). Of all agroecosystems, the perennial grazing system (soil health score, 24.7) was most similar to the native prairie (soil health score, 27.4), having high soil C and a large microbial community. Of the row cropping systems, the no‐till system approached the perennial systems better than the conventional till and unfertilized conventional till (soil health score, 11.1 vs. 8.0 and 5.3, respectively). This study highlights the value of perennial grass grazing in agroecosystems and appropriate best management practices. Expanding this analysis to other sites may provide additional insight.

show abstract

Soil organic matter and microbial community responses to semiarid croplands and grasslands management

Cited by 44 publications

References 37 publications

Soil organic matter dynamics in semiarid agroecosystems transitioning to dryland

Soil organic matter dynamics in semiarid agroecosystems transitioning to dryland

Grass Buffer Strips Improve Soil Health and Mitigate Greenhouse Gas Emissions in Center-Pivot Irrigated Cropping Systems

Cropping management in a livestock–pasture–crop integration modifies microbial communities, activity, and soil health score

Contact Info

Product

Resources

About