scholarly journals Microbial Signatures in Fertile Soils Under Long-Term N Management

2021 ◽  
Vol 1 ◽  
Author(s):  
María B. Villamil ◽  
Nakian Kim ◽  
Chance W. Riggins ◽  
María C. Zabaloy ◽  
Marco Allegrini ◽  
...  
Keyword(s):  
Management Practices ◽  
Cropping Systems ◽  
Block Design ◽  
N Fertilization ◽  
Rrna Gene ◽  
Ribosomal Database Project ◽  
Fertilization Rates ◽  
Continuous Corn ◽  
Potential Nitrification

Long-term reliance on inorganic N to maintain and increase crop yields in overly simplified cropping systems in the U.S. Midwest region has led to soil acidification, potentially damaging biological N2 fixation and accelerating potential nitrification activities. Building on this published work, rRNA gene-based analysis via Illumina technology with QIIME 2.0 processing was used to characterize the changes in microbial communities associated with such responses. Amplicon sequence variants (ASVs) for each archaeal, bacterial, and fungal taxa were classified using the Ribosomal Database Project (RDP). Our goal was to identify bioindicators from microbes responsive to crop rotation and N fertilization rates following 34–35 years since the initiation of experiments. Research plots were established in 1981 with treatments of rotation [continuous corn (Zea mays L.) (CCC) and both the corn (Cs) and soybean (Glycine max L. Merr.) (Sc) phases of a corn-soybean rotation], and of N fertilization rates (0, 202, and 269 kg N/ha) arranged as a split-plot in a randomized complete block design with three replications. We identified a set of three archaea, and six fungal genera responding mainly to rotation; a set of three bacteria genera whose abundances were linked to N rates; and a set with the highest number of indicator genera from both bacteria (22) and fungal (12) taxa responded to N fertilizer additions only within the CCC system. Indicators associated with the N cycle were identified from each archaeal, bacterial, and fungal taxon, with a dominance of denitrifier- over nitrifier- groups. These were represented by a nitrifier archaeon Nitrososphaera, and Woesearchaeota AR15, an anaerobic denitrifier. These archaea were identified as part of the signature for CCC environments, decreasing in abundance with rotated management. The opposite response was recorded for the fungus Plectosphaerella, a potential N2O producer, less abundant under continuous corn. N fertilization in CCC or CS systems decreased the abundance of the bacteria genera Variovorax and Steroidobacter, whereas Gp22 and Nitrosospira only showed this response under CCC. In this latter system, N fertilization resulted in increased abundances of the bacterial denitrifiers Gp1, Denitratisoma, Dokdonella, and Thermomonas, along with the fungus Hypocrea, a known N2O producer. The identified signatures could help future monitoring and comparison across cropping systems as we move toward more sustainable management practices. At the same time, this is needed primary information to understand the potential for managing the soil community composition to reduce nutrient losses to the environment.

scholarly journals Soil properties after 36 years of N fertilization under continuous corn and corn-soybean management

2021 ◽  
Author(s):  
Nakian Kim ◽  
Gevan D. Behnke ◽  
María B. Villamil
Keyword(s):  
Soil Properties ◽  
Crop Rotation ◽  
Crop Yields ◽  
Inorganic Nitrogen ◽  
Block Design ◽  
N Fertilization ◽  
Total Carbon ◽  
Nitrous Oxide Emissions ◽  
Continuous Corn

Abstract. Modern agricultural systems rely on inorganic nitrogen (N) fertilization to enhance crop yields, but its overuse may negatively affect soil properties. Our objective was to investigate the effect of long-term N fertilization on key soil properties under continuous corn [Zea mays L.] (CCC) and both the corn (Cs) and soybean [Glycine max L. Merr.] (Sc) phases of a corn-soybean rotation. Research plots were established in 1981 with treatments arranged as a split-plot design in a randomized complete block design with three replications. The main plot was crop rotation (CCC, Cs, and Sc), and the subplots were N fertilizer rates of 0 kg N ha−1 (N0, controls), and 202 kg N ha−1, and 269 kg N ha−1 (N202, and N269, respectively). After 36 years and within the CCC, the yearly addition of N269 compared to unfertilized controls significantly increased cation exchange capacity (CEC, 65 % higher under N269) and acidified the top 15 cm of the soil (pH 4.8 vs. pH 6.5). Soil organic matter (SOM) and total carbon stocks (TCs) were not affected by treatments, yet water aggregate stability (WAS) decreased by 6.7 % within the soybean phase of the CS rotation compared to CCC. Soil bulk density (BD) decreased with increased fertilization by 5 % from N0 to N269. Although ammonium (NH4+) did not differ by treatments, nitrate (NO3−) increased eight-fold with N269 compared to N0, implying increased nitrification. Soils of unfertilized controls under CCC have over twice the available phosphorus level (P) and 40 % more potassium (K) than the soils of fertilized plots (N202 and N269). On average, corn yields increased 60 % with N fertilization compared to N0. Likewise, under N0, rotated corn yielded 45 % more than CCC; the addition of N (N202 and N269) decreased the crop rotation benefit to 17 %. Our results indicated that due to the increased level of corn residues returned to the soil in fertilized systems, long-term N fertilization improved WAS and BD, yet not SOM, at the cost of significant soil acidification and greater risk of N leaching and increased nitrous oxide emissions.

scholarly journals Covariance Structures in Conventional and Organic Cropping Systems

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Abdullah A. Jaradat
Keyword(s):  
Coefficient Of Variation ◽  
Repeated Measures ◽  
Management Practices ◽  
Cropping Systems ◽  
Block Design ◽  
Crop Rotations ◽  
Covariance Structures ◽  
Cumulative Yield ◽  
Temporal Variance

Guidelines are needed to develop proper statistical analyses procedures and select appropriate models of covariance structures in response to expected temporal variation in long-term experiments. Cumulative yield, its temporal variance, and coefficient of variation were used in estimating and describing covariance structures in conventional and organic cropping systems of a long-term field experiment in a randomized complete block design. An 8-year database on 16 treatments (conventional and organic cropping systems, crop rotations, and tillage) was subjected to geostatistical, covariance structure, variance components, and repeated measures multivariate analyses using six covariance models under restricted maximum likelihood. Differential buildup of the cumulative effects due to crop rotations being repeated over time was demonstrated by decreasing structured and unstructured variances and increasing range estimates in the geostatistical analyses. The magnitude and direction of relationships between cumulative yield and its temporal variance, and coefficient of variation shaped the covariance structures of both cropping systems, crop rotations, and phases within crop rotations and resulted in significant deviations of organic management practices from their conventional counterparts. The unstructured covariance model was the best to fit most factor-variable combinations; it was the most flexible, but most costly in terms of computation time and number of estimated parameters.

scholarly journals Impacts of Cropping Systems and Long-Term Tillage on Soil Microbial Population Levels and Community Composition in Dryland Agricultural Setting

ISRN Ecology ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Justin P. Ng ◽  
Emily B. Hollister ◽  
Ma. del Carmen A. González-Chávez ◽  
Frank M. Hons ◽  
David A. Zuberer ◽  
...  
Keyword(s):  
Triticum Aestivum ◽  
Management Practices ◽  
Cropping Systems ◽  
Conventional Tillage ◽  
Microbial Biomass C ◽  
Rrna Gene ◽  
Soil Microbial ◽  
No Till ◽  
Soil Microbial Population

Few studies have used molecular methods to correlate the abundance of specific microbial taxonomic groups with changes in soil properties impacted by long-term agriculture. Community qPCR with 16S rRNA gene sequencing to examine the effects of long-term crop-management practices (no-till vs. conventional tillage, and continuous wheat (Triticum aestivum L.) vs. sorghum-wheat-soybean rotation (Sorghum bicolor L. Moench-Triticum aestivum L.-Glycine max L. Merr) on bacterial and fungal relative abundances and identify the dominant members of the soil microbial community. The qPCR assays revealed that crop rotation decreased bacterial copy numbers, but no-till practices did not significantly alter bacteria or fungi relative to conventional tillage. Cyanobacteria were more abundant while Actinobacteria were less numerous under continuous wheat. Acidobacteria and Planctomycetes were positively correlated with soil microbial biomass C and N. This study highlights ways cropping systems affect microbial communities and aids the development of sustainable agriculture.

scholarly journals Tallgrass Prairie Responses to Management Practices and Disturbances: A Review

Agronomy ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 300 ◽  
Author(s):  
Pradeep Wagle ◽  
Prasanna Gowda
Keyword(s):  
Species Richness ◽  
Soil Quality ◽  
Plant Species ◽  
Tallgrass Prairie ◽  
Management Practices ◽  
The United States ◽  
N Fertilization ◽  
Native Plant ◽  
The Impact

Adoption of better management practices is crucial to lessen the impact of anthropogenic disturbances on tallgrass prairie systems that contribute heavily for livestock production in several states of the United States. This article reviews the impacts of different common management practices and disturbances (e.g., fertilization, grazing, burning) and tallgrass prairie restoration on plant growth and development, plant species composition, water and nutrient cycles, and microbial activities in tallgrass prairie. Although nitrogen (N) fertilization increases aboveground productivity of prairie systems, several factors greatly influence the range of stimulation across sites. For example, response to N fertilization was more evident on frequently or annually burnt sites (N limiting) than infrequently burnt and unburnt sites (light limiting). Frequent burning increased density of C4 grasses and decreased plant species richness and diversity, while plant diversity was maximized under infrequent burning and grazing. Grazing increased diversity and richness of native plant species by reducing aboveground biomass of dominant grasses and increasing light availability for other species. Restored prairies showed lower levels of species richness and soil quality compared to native remnants. Infrequent burning, regular grazing, and additional inputs can promote species richness and soil quality in restored prairies. However, this literature review indicated that all prairie systems might not show similar responses to treatments as the response might be influenced by another treatment, timing of treatments, and duration of treatments (i.e., short-term vs. long-term). Thus, it is necessary to examine the long-term responses of tallgrass prairie systems to main and interacting effects of combination of management practices under diverse plant community and climatic conditions for a holistic assessment.

scholarly journals Maximizing Yields, Nutrient Uptake and Balance for Mustard-Mungbean-T. Aman Rice Cropping Systems through Nutrient Management Practices in Calcareous Soils

2017 ◽  
Vol 9 (9) ◽  
pp. 210 ◽  
Author(s):  
M. A. Quddus ◽  
M. J. Abedin Mian ◽  
H. M. Naser ◽  
M. A. Hossain ◽  
S. Sultana
Keyword(s):  
Nutrient Uptake ◽  
Management Practices ◽  
Nutrient Management ◽  
Crop Yields ◽  
Cropping Systems ◽  
Block Design ◽  
Calcareous Soils ◽  
Cropping System ◽  
Soil Test ◽  
Positive Balance

The experiment was conducted to measure crop yields, nutrient concentration, nutrient uptake and balance by using different nutrient management practices for mustard-mungbean-T. aman rice cropping system in calcareous soil of Madaripur, Bangladesh. Different nutrient management practices were absolute nutrient control (T1); farmer’s practice (T2); AEZ based nutrient application (T3) and soil test based nutrient application (T4). The practices were compared in a randomized completely block design with three replications over two consecutive years. The average yield through application of soil test based nutrient (T4) was showed effective to get highest yields of mustard (1530 kg ha-1), mungbean (1632 kg ha-1) and T. aman rice (4729 kg ha-1). The same practices (T4) exhibited the greatest nutrients uptake by the test crops. The apparent balance of N and K was negative; however it was less negative and less deficiency detect in T4 treatment. Positive balance of P observed in all practices except in T1. There was a positive S balance (7.60 kg ha-1) in T4 but negative in T1, T2 and T3. Zinc balance was found positive in T3 and T4 and negative in T1 and T2. Boron balance in the system was neutral or slightly positive in T1 and negative in T2 but positive in T3 and T4. Organic matter, N, P, S, Zn and B status in soil was improved by T4 treatment. The results suggested that the soil test based nutrient application is viable and sustainable for mustard-mungbean-T. aman rice cropping system in calcareous soils of Bangladesh.

Long term effects of tillage practices and N fertilization in rainfed Mediterranean cropping systems: durum wheat, sunflower and maize grain yield

2016 ◽  
Vol 77 ◽  
pp. 166-178 ◽  
Author(s):  
Giovanna Seddaiu ◽  
Ileana Iocola ◽  
Roberta Farina ◽  
Roberto Orsini ◽  
Giuseppe Iezzi ◽  
...  
Keyword(s):  
Grain Yield ◽  
Durum Wheat ◽  
Cropping Systems ◽  
N Fertilization ◽  
Long Term Effects ◽  
Tillage Practices ◽  
Maize Grain Yield ◽  
Maize Grain

EFFECTS OF CROPPING SYSTEM ON STRUCTURE OF BROOKSTON CLAY LOAM IN LONG-TERM EXPERIMENTAL PLOTS AT WOODSLEE, ONTARIO

1987 ◽  
Vol 67 (3) ◽  
pp. 571-584 ◽  
Author(s):  
J. A. McKEAGUE ◽  
C. A. FOX ◽  
J. A. STONE ◽  
R. PROTZ
Keyword(s):  
Bulk Density ◽  
Cropping Systems ◽  
Poa Pratensis ◽  
Cropping System ◽  
Clay Loam ◽  
Water Desorption ◽  
Continuous Corn ◽  
Ap Horizon ◽  
Loam Soil

Macro- and microstructure were described and water desorption characteristics were measured for a Brookston clay loam soil under different cropping systems. The Ap horizon of the long-term corn (Zea mays L.) plots differed markedly from those of a bluegrass (Poa pratensis L.) plot and a never-cultivated plot as follows: massive as opposed to strongly structured, macroporosity (pore width > 60 μm) ≤ 6% as opposed to more than 10%, isolated pores as opposed to interconnected pores, bulk density 1.4–1.5 Mg m−3 as opposed to 1.0–1.3 Mg m−3. The Ap horizon of the rotation plots, oats (Avena sativa L.), alfalfa (Medicago sativa L.), alfalfa, corn, differed from those of the continuous corn plots in having many more biopores larger than 0.5 mm in diameter (≥ 0.2% relative to ≤ 0.02%). Below a depth of 30 cm comparable horizons of soils from all plots were similar in structure, bulk density and water characteristic curves. Key words: Porosity, biopores, compaction, macromorphology, image analysis

Corn yield after 10 years of different cropping sequences and weed management practices

1996 ◽  
Vol 76 (4) ◽  
pp. 795-797 ◽  
Author(s):  
Jianhua Zhang ◽  
Allan S. Hamill ◽  
Susan E. Weaver
Keyword(s):  
Crop Rotation ◽  
Weed Management ◽  
Management Practices ◽  
Cropping Systems ◽  
Land Use History ◽  
Corn Yield ◽  
Cereal Crop ◽  
Herbicide Application ◽  
Continuous Corn ◽  
Effects Of Land Use

In this study, corn yield was measured after 10 yr of various rotational sequences of corn, soybeans, and wheat or oats, and under three levels of weed management to determine the effects of land use history on crop yield. Corn yield varied significantly with both crop rotation and weed management. Com yields were lower after continuous corn or soybeans or immediately following corn, and higher after a cereal crop or a rotation including a cereal. Herbicide application alone maintained significantly higher corn yield than inter-row cultivation across cropping systems. Key words: Corn yield, crop rotation, Zea mays

The role of long-term sites in agroecological research: A case study

1995 ◽  
Vol 75 (1) ◽  
pp. 123-133 ◽  
Author(s):  
H. H. Janzen
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Management Practices ◽  
Cropping Systems ◽  
Simulation Models ◽  
Sample Collection ◽  
Productivity Measurement ◽  
Sampling Protocols ◽  
Long Term Studies

Gradual, episodic or subtle changes in agroecosystems can be definitively measured only in long-term studies. The objective of this paper is to illustrate the benefits and limitations of long-term agroecological sites using a crop rotation study (Rotation ABC) established at Lethbridge, Alberta in 1910. Long-term agroecological sites, envisioned as part of a continuum of research levels, seek to determine the persistence of cropping systems with respect to their effects on soil resources and the larger environment. Examples of research findings arising from such sites include the documentation of long-term changes in agricultural productivity, measurement of organic matter changes over time, calculation of long-term nutrient budgets, and verification of simulation models. For example, soil organic matter concentrations in Rotation ABC were found to decline abruptly within the first few decades of cultivation and then approach a new steady state. Despite the continual removal of N in harvested grain, soil N concentrations also appear to have stabilized, suggesting an accession of N approximately equivalent to the amount harvested. Common limitations of long-term sites like that at Lethbridge include: rudimentary experimental design, evolving management practices, incidental changes at the sites, and variation in sampling protocols. The successful use of long-term agroecological sites depends on well-defined objectives, simplicity of design, adequate scale, consistent data and sample collection, and collaboration among sites. The primary justification for the establishment and maintenance of long-term agroecological sites may be their future role in answering questions not yet envisioned. Key words: Soil organic matter, long-term studies, crop rotations, sustainability, fertilizer

scholarly journals Simulating the Long-Term Effects of Fertilizer and Water Management on Grain Yield and Methane Emissions of Paddy Rice in Thailand

Agriculture ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1144
Author(s):  
Nittaya Cha-un ◽  
Amnat Chidthaisong ◽  
Kazuyuki Yagi ◽  
Sirintornthep Towprayoon
Keyword(s):  
Water Management ◽  
Grain Yield ◽  
Management Practices ◽  
Cropping Systems ◽  
Rice Grain ◽  
Management Options ◽  
Irrigated Rice ◽  
Ch4 Emissions ◽  
Rice Cropping Systems

Rice is an important economic crop in Thailand. However, paddy rice fields are one of the largest anthropogenic sources of methane (CH4) emissions. Therefore, suitable crop management practice is necessary to reduce CH4 emissions while rice grain yield is maintained. This study aimed to evaluate appropriate options of fertilizer and water management practices for Thai rice cultivation with regards to improving rice grain yield and reducing CH4 emissions. The Denitrification–Decomposition (DNDC) model was used to simulate grain yield and the emission of CH4 under the three fertilizer options (chemical fertilizer (F), manure (M) and chemical fertilizer + manure (F + M)) with three water management options (continuous flooding (CF), mid-season drainage (MD) and alternate wet and dry (AWD)) during the years 2011–2050. Rain-fed and irrigated rice cropping systems were used. A total of 24 sites distributed in 22 provinces were studied. The data sets of daily climate, soil properties, and rice management practices were required as inputs in the model. Model validation with observation data in a field experiment indicated that simulated grain yields (R2 = 0.83, slope = 0.98, NRMES = 0.30) and cumulative seasonal CH4 emissions (R2 = 0.83, slope = 0.74, NRMES = 0.43) were significantly and positively correlated with the observation. At the end of the simulation period (2046–2050), fertilizer management options of F and F + M gave more grain yield than the M management option by 1–44% in rain-fed rice cropping and 104–190% in irrigated rice cropping system, respectively. Among options, the lower CH4 emissions were found in AWD water management options. The appropriate options with regard to maintaining grain yield and reducing CH4 emissions in the long term were suggested to be F + M with AWD for the rain-fed rice, and F with AWD for the irrigated rice cropping systems.

Sign in / Sign up

Export Citation Format

Share Document