Strength of Microbes in Nutrient Cycling: A Key to Soil Health

Soil health connotes the balance of biological, physicochemical, nutritional, structural, and water-holding components necessary to sustain plant productivity. Despite a substantial knowledge base, achieving sustainable soil health remains a goal because it is difficult to simultaneously: (i) improve soil structure, physicochemistry, water-holding capacity, and nutrient cycling; (ii) suppress pests and diseases while increasing beneficial organisms; and (iii) improve biological functioning leading to improved biomass/crop yield. The objectives of this review are (a) to identify agricultural practices (APs) driving soil health degradations and barriers to developing sustainable soil health, and (b) to describe how the nematode community analyses-based soil food web (SFW) and fertilizer use efficiency (FUE) data visualization models can be used towards developing sustainable soil health. The SFW model considers changes in beneficial nematode population dynamics relative to food and reproduction (enrichment index, EI; y-axis) and resistance to disturbance (structure index, SI; x-axis) in order to identify best-to-worst case scenarios for nutrient cycling and agroecosystem suitability of AP-driven outcomes. The FUE model visualizes associations between beneficial and plant-parasitic nematodes (x-axis) and ecosystem services (e.g., yield or nutrients, y-axis). The x-y relationship identifies best-to-worst case scenarios of the outcomes for sustainability. Both models can serve as platforms towards developing integrated and sustainable soil health management strategies on a location-specific or a one-size-fits-all basis. Future improvements for increased implementation of these models are discussed.

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Soil Microarthropods and Soil Health: Intersection of Decomposition and Pest Suppression in Agroecosystems

Insects ◽

10.3390/insects10120414 ◽

2019 ◽

Vol 10 (12) ◽

pp. 414 ◽

Cited By ~ 2

Author(s):

Deborah Neher ◽

Mary Barbercheck

Keyword(s):

Nutrient Cycling ◽

Insect Pests ◽

Global Climate ◽

Relevant Literature ◽

Soil Health ◽

Research Priorities ◽

Future Research ◽

Soil Microarthropods ◽

Change Models ◽

Pest Suppression

Two desirable functions of healthy soil are nutrient cycling and pest suppression. We review relevant literature on the contributions of soil microarthropods to soil health through their intersecting roles in decomposition and nutrient cycling and direct and indirect suppression of plant pests. Microarthropods can impact soil and plant health directly by feeding on pest organisms or serving as alternate prey for larger predatory arthropods. Indirectly, microarthropods mediate the ability of crop plants to resist or tolerate insect pests and diseases by triggering induced resistance and/or contributing to optimal nutritional balance of plants. Soil fauna, including microarthropods, are key regulators of decomposition at local scales but their role at larger scales is unresolved. Future research priorities include incorporating multi-channel omnivory into food web modeling and understanding the vulnerability of soil carbon through global climate change models.

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Potential Indicators of Soil Health Degradation in Different Land Use-Based Ecosystems in the Shiwaliks of Northwestern India

Sustainability ◽

10.3390/su11143908 ◽

2019 ◽

Vol 11 (14) ◽

pp. 3908 ◽

Cited By ~ 5

Author(s):

Arnab Bhowmik ◽

Surinder Singh Kukal ◽

Debasish Saha ◽

Harmandeep Sharma ◽

Anu Kalia ◽

...

Keyword(s):

Land Use ◽

Nutrient Cycling ◽

Land Degradation ◽

Soil Health ◽

Health Indicators ◽

Soil Microflora ◽

Enzymatic Activities ◽

Soil Biology ◽

Soil C ◽

Land Use Systems

Identifying the importance of soil biology in different land use systems is critical to assess the present conditions of declining soil (C) and global land degradation while regulating soil health and biogeochemical nutrient cycling. A study was undertaken in a mixed watershed comprising of different land use systems (agricultural, grassland, agroforestry, and eroded); situated in the Shiwalik region in the foot hills of the lower Himalayas in India, a fragile ecosystem susceptible to land degradation. Soil samples from 0–15 and 15–30 cm depths were collected from these land use systems and analyzed for a suite of different soil health indicators, including physio-chemical soil properties, aggregate stability, soil microflora, and the enzymatic activities that are critical for nutrient cycling. Principal component analysis was used to group different land uses and understand their association with soil microflora, enzyme activities, and soil physio-chemical properties. We found that a greater number of soil microflora and enzymatic activities were associated with grassland and agroforestry land use systems. Aggregate-associated soil C correlated well with the soil microflora under different land use systems studied. The biplots revealed that the fungal:bacterial ratio (2 × 103–0.1 × 103) was a robust indicator of C accumulation and soil health, and was in greater association with the agroforestry land use system. Random forest, a non-parametric statistical test, on average explained that 68% to 92% of the variability in soil microbial population was due to land use and other soil health properties. Overall, the biological soil health indicators used in this study demonstrated the fact that land use management systems that employ constant crop cover with minimal disturbance have the potential to improve soil sustainability and ecological functioning.

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Soil microarthropods and soil health: Intersection of decomposition and pest suppression

10.20944/preprints201911.0093.v1 ◽

2019 ◽

Author(s):

Deborah A. Neher ◽

Mary E. Barbercheck

Keyword(s):

Nutrient Cycling ◽

Food Web ◽

Recent Literature ◽

Insect Pests ◽

Soil Health ◽

Research Priorities ◽

Future Research ◽

Soil Microarthropods ◽

Pests And Diseases ◽

Pest Suppression

Two desirable functions of healthy soil are nutrient cycling and pest suppression. We review recent literature on the contributions of soil microarthropods to soil health through their intersecting roles in decomposition and nutrient cycling and direct and indirect suppression of plant pests. Microarthropods can impact soil and plant health directly by feeding on pest organisms or serving as alternate prey for larger predatory arthropods, and indirectly, by mediating the ability of crop plants to resist or tolerate insect pests and diseases through interactions with the decomposition food web in support of plant nutrition. Soil fauna, including microarthropods, are key regulators of decomposition at local scales but their role at larger scales is unresolved. Future research priorities include the incorporation of multi-channel omnivory into food web modeling and understanding the vulnerability of our soil carbon to increased global temperatures.

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Effects of Detritivores on Nutrient Dynamics and Corn Biomass in Mesocosms

Insects ◽

10.3390/insects10120453 ◽

2019 ◽

Vol 10 (12) ◽

pp. 453

Author(s):

Josephine Lindsey-Robbins ◽

Angélica Vázquez-Ortega ◽

Kevin McCluney ◽

Shannon Pelini

Keyword(s):

Nutrient Cycling ◽

Soil Solution ◽

Nutrient Dynamics ◽

Nutrient Management ◽

Soil Health ◽

Soil Nutrient ◽

Freshwater Ecosystems ◽

Significant Interaction Effect ◽

Total N ◽

Soil Nutrient Cycling

(1) Background: Strategies aimed at managing freshwater eutrophication should be based on practices that consider cropland invertebrates, climatic change, and soil nutrient cycling. Specifically, detritivores play a crucial role in the biogeochemical processes of soil through their consumptive and burrowing activities. Here, we evaluated the effectiveness of increasing detritivore abundance as a strategy for nutrient management under varied rainfall. (2) Methods: We manipulated soil macroinvertebrate abundance and rainfall amount in an agricultural mesocosms. We then measured the phosphorus, nitrogen, and carbon levels within the soil, corn, invertebrates, and soil solution. (3) Results: Increasing detritivore abundance in our soil significantly increased corn biomass by 2.49 g (p < 0.001), reduced weed growth by 18.2% (p < 0.001), and decreased soil solution nitrogen and total organic carbon (p < 0.05) and volume by 31.03 mL (p < 0.001). Detritivore abundance also displayed a significant interaction effect with rainfall treatment to influence soil total P (p = 0.0019), total N (p < 0.001), and total C (p = 0.0146). (4) Conclusions: Soil detritivores play an important role in soil nutrient cycling and soil health. Incorporating soil macroinvertebrate abundance into management strategies for agricultural soil may increase soil health of agroecosystems, preserve freshwater ecosystems, and protect the valuable services they both provide for humans.

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Veganic Agriculture in the United States: Opportunities for Research, Outreach, and Education

Journal of Extension ◽

10.34068/joe.59.03.08 ◽

2021 ◽

Vol 59 (Summer 2021) ◽

Author(s):

Alisha Utter ◽

Mona Seymour

Keyword(s):

United States ◽

Nutrient Cycling ◽

Organic Agriculture ◽

Crop Production ◽

Critical Role ◽

Soil Health ◽

The United States ◽

Research Institutions ◽

Produce Safety ◽

Innovative Methods

A growing number of farmers are excluding animal inputs from crop production, an approach commonly referred to as veganic or stockfree organic agriculture. This research-based article discusses the soil health and fertility strategies reported by a sample of U.S. veganic farmers. These approaches may be relevant beyond the veganic community to farmers seeking innovative methods for produce safety and nutrient cycling. Agricultural outreach professionals (AOPs), including Extension personnel, play a critical role in supporting veganic practices by serving as cross-pollinators between farmers and research institutions. Thus, the article endeavors to expand AOP familiarity with veganic practices and benefits.

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Effect of gold nanoparticles on extracellular nutrient-cycling enzyme activity and bacterial community in soil slurries: role of nanoparticle size and surface coating

Environmental Science Nano ◽

10.1039/c6en00567e ◽

2017 ◽

Vol 4 (4) ◽

pp. 907-918 ◽

Cited By ~ 16

Author(s):

Bahareh Asadishad ◽

Shawninder Chahal ◽

Vanessa Cianciarelli ◽

Kevin Zhou ◽

Nathalie Tufenkji

Keyword(s):

Gold Nanoparticles ◽

Enzyme Activity ◽

Bacterial Community ◽

Nutrient Cycling ◽

Surface Coating ◽

Soil Health ◽

Soil Enzyme ◽

Engineered Nanoparticles ◽

Soil Enzyme Activities

Engineered nanoparticles such as gold that are considered to be relatively chemically inert can influence soil enzyme activities and the composition of microbial communities that play an important role in nutrient cycling and soil health.

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