Effects Of Soil Management Research Articles

Soil development and management effects on hydraulic properties along a granitic soil toposequence in southern China

A profound understanding of the effects of natural soil development and anthropogenic land management on soil hydraulic properties is essential for soil productivity and water conservation. The objective of our research was to explore the effects of soil development on soil bulk density (BD), pore size distribution, saturated hydraulic conductivity (Ksat), and soil water retention characteristics under horseweed grass (Erigeron canadensis) and corn (Zea mays)-rapeseed (Brassica napus) rotation systems in weathered granitic soils in southern China. Pore size classes determined were macropores (effective diameter > 1000 μm), coarse mesopores (effective diameter 60–1000 μm), fine mesopores (effective diameter 10–60 μm), and micropores (effective diameter < 10 μm). Soil samples from each treatment were collected to a depth of 40 cm in 10 cm increments. The results showed that Ksat was highest in Entisols (6.08 cm h−1) and lowest in Alfisols (2.58 cm h−1), and these values were averaged across management systems and depths. The saturated water content was 12.8% higher in Alfisols than that in Entisols. With soil development, soil water retention increased for all measured soil water pressures. The highest macroporosity as well as coarse and fine mesoporosity were recorded in Entisols, while the highest microporosity was found in Alfisols. Improvement in soil physical and hydraulic properties was seen in the horseweed grass system (HG) compared with that in the corn-rapeseed rotation system (CR). The bulk density was 6% lower for the HG than that for the CR. The HG had 30% higher Ksat and 10.3% greater saturated water content than the CR. The HG also had 15.2% increased macroporosity compared with the CR, which may enhance water infiltration and reduce runoff loss.

Relative entropy as an index of soil structure

AbstractSoil structure controls key soil functions in both natural and agro‐ecosystems. Thus, numerous attempts have been made to develop methods aiming at its characterization. Here we propose an index of soil structure that uses relative entropy to quantify differences in the porosity and pore(void)‐size distribution (VSD) between a structured soil derived from soil water retention data and the same soil without structure (a so‐called reference soil) estimated from its particle‐size distribution (PSD). The difference between these VSDs, which is the result of soil structure, is quantified using the Kullback–Leibler Divergence (KL divergence). We applied the method to soil data from two Swedish field experiments that investigate the long‐term effects of soil management (fallow vs. inorganic fertilizer vs. manure) and land use (afforested land vs. agricultural land dominated by grass/clover ley) on soil properties. The KL divergence was larger for the soil receiving regular addition of manure compared with the soils receiving no organic amendments. Furthermore, soils under afforested land showed significantly larger KL divergences compared to agricultural soils near the soil surface, but smaller KL divergences in deeper soil layers, which closely mirrored the distribution of organic matter in the soil profile. Indeed, a significant positive correlation (r = 0.374, p &lt; 0.001) was found between soil organic carbon concentrations and KL divergences across all sites and treatments. Despite challenges related to modelling the VSD of the reference soil without structure, the proposed index proved useful for evaluating differences in soil structure in response to soil management and land‐use change and reflected the expected effects of soil organic matter on soil structure. We conclude that relative entropy shows great potential to serve as an easy‐to‐use index of soil structure, as it only requires widely available data on soil physical and hydraulic properties.Highlights A new index of soil structure is proposed based on relative entropy A method is developed that separates the effects of soil texture and structure on the pore space The index identified soil structural differences in response to land use and soil organic carbon concentrations (SOC) The index shows the potential to serve as an easy‐to‐use metric of soil structure

Modelling climate change impact on soil loss and erosion vulnerability in a watershed of Shiwalik Himalayas

Understanding the impact of climate change on soil erosion is required to plan effective soil conservation and management practices in hilly and mountainous landscape. Though, few studies have been executed in Indian Himalayas, much less in Shiwalik Himalayas. Thus, keeping this in view, the aim of the study is to estimate the possible impact of projected climate change scenarios on soil loss and erosion vulnerability using Statistical Downscaling Model (SDSM), MarkSim Weather Generator, Agricultural Policy Environmental eXtender (APEX) model and AHP method. The present study downscaled four climate scenarios on the near-future, noted the 2020 s (2011–2040), mid-future, noted 2050 s (2011–2070) and far-future, noted 2080 s (2071–2100/2095) under two Special Report Emission Scenarios (SRES), A2 and B2 with two Representative Concentration Pathway (RCP), 4.5 and 8.5 scenarios. Both SRES and RCP scenarios predicted an increase in temperature and annual rainfall depth during 21st century. Calibrated APEX model was used to simulate future soil loss. The study exposed that the average annual soil loss might increase up to 46.94%, 38.80%, 35.34% and 25.93% in the A2, B2, RCP 4.5 and RCP 8.5 scenarios respectively from the base period (1985–2014). The vulnerability assessment indicates, most of the areas might be under risk from slightly to highly vulnerable and was found that forest land cover could resist this erosion vulnerability to a certain extent. The findings of the study showed a possibility for climate change to increase the rate of soil loss unless conservation strategies or proper land use plans are remunerated. This study offers scientists and policymakers to a detailed understanding of the future impact of rainfall on soil loss and erosion vulnerability in the Shiwalik Himalayas.

Vegetation increases abundances of ground and canopy arthropods in Mediterranean vineyards

The decline of arthropod populations observed in many parts of the world is a major component of the sixth mass extinction with intensive agriculture being one of its main drivers. Biodiversity-friendly farming practices are taking centre stage in the recovery process. In vineyards, vegetation cover is commonly used for production purposes, to reduce soil compaction by machinery use and soil erosion. Here we examined the effects of vegetation cover and soil management on the abundance of ground- (spiders, beetles, Hemiptera and harvestmen) and canopy-dwelling (wild bees, green lacewings, beetles and Hemiptera) arthropods in three categories of vineyards: (i) vineyards with no vegetation, (ii) partially vegetated (every second inter-row is vegetated) and (iii) all inter-rows are vegetated. We recorded a general positive effect of a decrease in soil perturbation intensity and corresponding higher vegetation cover on arthropod abundance. Plant species richness was the most important vegetation parameter, with a positive effect on spiders, harvestmen, hemipterans and beetles (ground and canopy) abundances. Using a path analysis, we also highlighted the central role of inter-row vegetation management in trophic and non-trophic relationships between vegetation and arthropods, and between arthropod groups. Our results demonstrate the benefits of a softer soil management preserving a diverse vegetation cover for the conservation of arthropods in Mediterranean vineyards.

Effects of Different Inter-Row Soil Management and Intra-Row Living Mulch on Spontaneous Flora, Beneficial Insects, and Growth of Young Olive Trees in Southern Italy.

Conservation agriculture (i.e., minimized soil disturbance and permanent soil covering) and living mulches represent two agroecological practices that can improve soil fertility, spontaneous flora, and beneficial insect communities. This research studied the effect of these practices in a young olive orchard in the Mediterranean area. Two Sicilian olive cultivars (‘Nocellara del Belice’ and ‘Nocellara etnea’) were used for the field experiment; inter-row minimum and zero tillage and four species of aromatic plants as living mulch along the row were tested. Spontaneous flora and beneficial insect communities, as well as tree growth, were monitored. The inter-row management did not influence the spontaneous flora dynamics. The species adopted for living mulch showed a very different degree of development and soil cover; 69 insect species (pollinators and predators) belonging to five orders (Hymenoptera, Lepidoptera, Diptera, Neuroptera, and Coleoptera) and 17 families were recorded. The growth of the olive trees was not affected by the conservative strategies.: In the inter-row, the growth of the spontaneous flora was limited by the high temperatures during the summer. Among the living mulch species, sage and lemongrass guaranteed an almost full soil cover, reducing the need for weed management along the row, as well as increasing the beneficial insects without influencing the young tree growth.

Concentration and Toxicological Risk Assessment of Heavy Metal Pollution in Dumpsite Soils within Benin City, Nigeria

Indiscriminate disposal of refuse and industrial effluents is a challenge in Nigeria. This poses a plethora of health and ecological risks from heavy metal contamination of soils. This study investigated the levels of heavy metal contamination in dumpsite soils and its effects on human health within Benin metropolis, Nigeria. The specific objectives were to determine the human and ecological risks via different exposure pathways. Soil samples were collected from three sampling stations, digested and analyzed for lead, cadmium, zinc, chromium, iron, nickel, manganese and copper using the Atomic Absorption Spectrophotometer (AAS). Pollution Indices and Human health risk were estimated using appropriate formulae. Results showed that that the mean concentrations of the investigated metals in the three stations were chromium (17.12±1.00, 17.65±1.05 and, 17.24±1.05 mg/kg), nickel (37.60±7.95, 40.98±1.46 and, 41.25±0.92 mg/kg), copper (48.57±4.91, 47.76±3.66 and, 48.05±3.46 mg/kg), lead (8.2±0.22, 8.17±0.52 and, 8.25±0.16 mg/kg), manganese (94.52±4.90, 94.98±6.69 and, 95.06±4.63), iron (467.98±36.69, 464.90±22.36 and, 462.15±10.64 mg/kg), cadmium (2.30±0.16, 2.22±0.11 and, 2.22±0.10 mg/kg) and zinc (142.93±3.93, 142.29±3.41 and, 142.87±3.86 mg/kg) respectively. Human health risk assessment revealed that the highest and lowest daily intake for the ingestion, inhalation and dermal pathway for both adults and children were Zinc and lead. Daily intake for children was higher than for adults via the three pathways with lifetime cancer risk (LCR) higher for children than adults. Carcinogenic and non-carcinogenic risk assessment shows that there were minimal risks from heavy metal contamination of the soils. Effective management and continuous monitoring of dumpsite soils is recommended to prevent negative impacts to man and the environment.

Impact of Conservation Agriculture on Soil Erosion in the Annual Cropland of the Apulia Region (Southern Italy) Based on the RUSLE-GIS-GEE Framework

The processes of soil erosion and land degradation are more rapid in the case of inappropriate agricultural management, which leads to increased soil loss rates. Moreover, climatic conditions are one of the most important determining factors affecting agriculture, especially in the Mediterranean areas featuring irregular rainfall and high summer temperatures. Conservation agriculture (CA) can make a significant contribution to reducing soil erosion risk on the annual cropland (ACL) of the Mediterranean region in comparison with conventional management (CM). The objective of this study is to provide soil loss rate maps and calculate the values for each altitude and slope class and their combination for the Apulia region in four annual production cycles for the scenarios CM and CA. The present study estimates the significance of the adoption of CA on soil erosion assessment at regional scale based on the Revised Universal Soil Loss Equation (RUSLE) model. The parameters of the RUSLE model were estimated by using remote sensing (RS) data. The erosion probability zones were determined through a Geographic Information System (GIS) and Google Earth Engine (GEE) approach. Digital terrain model (DTM) at 8 m, ACL maps of the Apulia region, and rainfall and soil data were used as an input to identify the most erosion-prone areas. Our results show a 7.5% average decrease of soil loss rate during the first period of adoption of the four-year crop cycle—from 2.3 t ha−1 y−1 with CM to 2.1 t ha−1 y−1 with the CA system. CA reduced soil loss rate compared to CM in all classes, from 10.1% in hill class to 14.1% for hill + low slope class. These results can therefore assist in the implementation of effective soil management systems and conservation practices to reduce soil erosion risk in the Apulia region and in the Mediterranean basin more generally.

Improving irrigation, crop, and soil management for sustainable soybean production in Southern Brazilian lowlands

Lowlands have been cultivated with irrigated rice (Oryza sativa) in a monoculture cropping system for more than a century in southern Brazil. Shallow topsoil with high bulk density and deficient water infiltration favors the of production paddy rice; however, this condition does not favor species non-tolerant to flooding or oxygen restriction. Thus, soil and irrigation management may be necessary to raise the rice-soybean (Glycine max) rotation systems to sustainable levels. We carried out a two-year field experiment to assess the effects of irrigation treatments and soil management on soil physical properties, soybean growth, and grain yield in lowland systems. The experiment comprised a randomized block design with two factors and three replications. The main factor comprised the following irrigation treatments: sprinkler; surface, and rainfed. Four soil managements composed the second factor: conventional tillage (CT), no-tillage (NT), conventional tillage with raised-seedbed, and no-tillage with raised-seedbed. Soil physical properties, soil penetration resistance, crop parameters, grain yield and water productivity were evaluated. CT increased the soil penetration resistance near the soil surface layer. The highest soil bulk density at the 0.05-0.10 m layer in the CT reduces grain yield in rainfed soybean compared to NT. Supplementary irrigation increased soybean yield of about 36 % in years of uneven rainfall distribution. Sprinkler irrigation resulted in higher irrigated water productivity (90 %) compared to surface irrigation, contributing to a more sustainable increase in grain yield. Crop rotation in a no-tillage cropping scheme could improve the sustainability of diversified agriculture in lowlands.

Soil Management and Crop Practice Effect on Soil Water Infiltration and Soil Water Storage in the Humid Lowlands of Beles Sub-Basin, Ethiopia

To investigate the response of soil management and cropping practice on infiltration, a field experiment was conducted under natural environment on Nitisol of Pawi area. Eight treatments combining two soil management methods (Zero tillage and conventional tillage) and four crop covers (continuous maize, continuous soya bean, rotated maize, and maize soya bean intercrop) were laid out on permanent plots in a randomized complete block design (RCBD) with three replications. The results showed that soil management and crop cover significantly affect both the capacity and rate of infiltration. Relative to conventionally tilled continuous maize, zero tilled maize soya bean intercrop improved infiltration rate and infiltration by 164.6% and 148%, respectively. While maize rotation with zero tillage, maize soya bean intercropping with conventional tillage and maize with zero tillage methods improve infiltration rate by 117.8%, 105.8%, 108%, respectively. The soil management and crop cover practices such as maize with zero tillage, maize soya bean intercrop with zero tillage, rotated maize with conventional tillage, maize soya bean intercrop with conventional tillage, soya bean with zero tillage and rotated maize with zero tillage increased soil water storage in the order of 65mm, 41mm, 41mm, 35mm, 15mm and 13mm. Generally, zero tillage with greater cover is an appropriate method to improve infiltration and soil water storage.

Soil organic carbon storage, distribution, and influencing factors at different depths in the dryland farming regions of Northeast and North China

The knowledge of the spatial distribution of soil organic carbon (SOC) and of its influencing factors is crucial for understanding the global carbon cycle. Although the influence of climate, soil properties, and soil management on the SOC content has been extensively explored, their relative importance remains unclear, especially under dryland farming. Herein, we investigated the SOC density (SOCD) at different depths (0–10, 10–20, 20–30, and 30–40 cm) across an area of 37.79 × 104 km2 (420 sites) located in the dryland farming regions of Northeast and North China. The total SOC storage (SOCS) was estimated to be 1922.38 Tg, with a mean density of 5.78 kg C m−2 for the entire area. The three soil groups with the largest SOCS were Fluvo-aquic, Black, and Chernozem soils, accounting for 63.34% of the total SOCS in the study area. Overall, both the SOCD and SOCS increased from southwest to northeast at all investigated depths. A structural equation model was used to distinguish direct from indirect effects of different factors on SOCD. Soil properties (e.g., bulk density and pH) and natural conditions (e.g., mean annual temperature and mean annual precipitation) were found to be the main factors controlling the SOCD variation at depths of 10–20, 20–30, and 30–40 cm. However, the total (direct and indirect) effect of soil management on SOCD at a 0–10 cm depth was greater than that of natural conditions, and smaller than that of soil properties. With increasing soil depth, the total effect of natural conditions on SOCD changed from –0.33 to –0.58, whereas the indirect effect of soil management decreased from 0.47 to 0. These results indicate that compared with environmental factors, soil management practices such as tillage and fertilization had a greater influence on SOCD in the surface soil of dryland. Our study provides a valuable reference for future research on the long-term evolution of SOC in dryland farming regions.

Nitrous Oxide Consumption Potential in a Semi-Arid Agricultural System: Effects of Conservation Soil Management and Nitrogen Timing on nosZ Mediated N2O Consumption

Agricultural soils account for less than 10% of the total greenhouse gas (GHG) emissions in the United States but about 75% of nitrous oxide (N2O) emissions. Soil conservation practices, such as no-tillage, have the potential to mitigate GHG emissions. We examined the short-term consequences of no-tillage with a winter wheat cover crop (NTW) and no-tillage winter fallow (NT) on N2O emissions, N2O reducing bacterial populations, and overall soil bacterial abundance during the summer growing season in the southern Great Plains, United States. Conservation practices were coupled with nitrogen (N) fertilizer application timing (100% pre-plant, 100% mid-season, 40% pre-plant 60% mid-season, 100% pre-plant with N stabilizer). In addition, N2O emissions were measured to determine any functional effects of altering N fertilizer timing and changing bacterial populations. The combination of N treatment and conservation practice affected nosZ clade II abundance in the second year of the study. Diversity of nosZ clade II was evaluated to determine effects on non-typical N2O reducers which were highly abundant in this study. No nosZ clade II diversity effects were determined, although some clustering of conservation system and N treatments was observed in the second year. Nitrogen treatment affected N2O-N emissions during the summer of both years, likely related to overall increased microbial activity and N fertilizer application. Negative fluxes (consumption) of N2O-N were observed in every treatment and tillage combination and were most pronounced in the control (0 kg N ha−1). Negative fluxes are likely due to a combination of low inorganic-N concentrations at various points during the year and a robust clade II population driving N2O consumption. Altering conservation system and the timing of N fertilizer application affects the microbial community and will likely continue to select for unique communities as the system matures. This will also likely further impact N2O emissions from the system and may increase the rate and frequency of N2O consumption.

Portable, In-Situ Determination of Soil Nutrients

The sustainable future of our world depends fundamentally on soil fertility and the fine balance between soil nutrients and the physical soil environment. In order to feed 7 billion people, humans have more than doubled global land-based cycling of nitrogen (N) and greatly influenced cycles of other major nutrients (e.g. carbon (C), phosphorus (P), potassium (K) and Sulphur (S)). As a consequence, they are now out of balance, causing major environmental, health and economic problems. Insufficient access to nutrients limits food production and contributes to land degradation, while finite P reserves represent a potential risk for future global food security, requiring prudent use.These issues warrant effective soil management strategies across different spatial and temporal scales. Ultimately, this depends on how accurately we can measure nutrient levels in soils over a large area in real-time with a high spatial and temporal resolution that is economically feasible.In the last several years, we are focusing our efforts on modification and adaptation of Ion Selective Electrodes (ISEs) that hold great promise for in situ analysis of plant nutrients. Unfortunately, relatively poor precision and robustness as well as requirements for pre- and post measurement handling prohibit their reliable use in the field by non-trained personnel (e.g. farmers) which is our ultimate goal.We will herein describe and discuss our efforts on the development of significantly simplified sensor substrates, measuring protocols, and integration with statistical methods aimed at improvement of precision. Moreover, we will demonstrate recent data obtained using our newly developed portable device that allows in situ determination of up to 16 analytes enhanced with the wireless data transmission capability.

Diversification and Soil Management Effects on the Quality of Organic Apricots

Nutritional and commercial value of the apricot fruits depends on the interaction among several factors, including the management strategies, the environmental conditions, and the genotype. This study aimed to evaluate the effect of orchard management and pedoclimatic conditions on apricot fruit quality traits (soluble solids, titratable acidity, dry matter and soluble solids and titratable acidity ratio) and phytochemical content (total phenolic content and antioxidant activity). Two apricot cultivars (Kioto* and Pieve*) were subjected to three different organic systems: (i) a standard management (BAU), (ii) an innovative diversified system with reduced tillage based on the natural cover conservation (INC) and (iii) an innovative diversified system with introduction of different cover crops (ICC), for two consecutive years (2019–2020). Overall, besides the effect of the climatic conditions, the multivariate analysis revealed the role of management systems, rather than genotype, on the quality of apricot fruits. In particular, INC soil management positively affected soluble solids, titratable acidity and dry matter parameters, especially in environments with low precipitation and high solar radiation (20.7 ± 1.7 g 100 g−1 FW, 19.9 ± 2.5 g MA 100 g−1 FW and 0.23 ± 0.2 g 100 g−1 FW respectively). In addition, the results indicate that ICC management showed the highest antioxidant values (1.45 ± 0.19 μg of Trolox equivalent (TE) 100 mg−1 FW), especially in the environment with high precipitation. This study was a useful tool for farmer to choose an effective organic system management in order to obtain fruits with high quality parameters.

Effects of cover crops and irrigation on ‘Tempranillo’ grapevine and berry physiology: an experiment under the Mediterranean conditions of Southern Portugal

In addition to irrigation, other viticultural practices such as soil management can be applied to improve grapevine (Vitis vinifera L.) quality responses and attenuate unfavourable environmental conditions. Cover crops in the interrow of irrigated vineyards change the dynamics of water extraction and it is expected that the patterns of vines’ water relations will be modified, also changing their productive responses. This study took place over two seasons in ‘Tempranillo’ grapevines in a vineyard in South Portugal, where a cover crop was sown in the inter-rows of half the study area (SCC) while maintaining resident vegetation in the remaining (RV). Five water regime treatments were applied: full irrigation (200 mm irrigation amount–I200); moderate irrigation (150 mm–I150); deficit irrigation (100 mm–I100); ultra-deficit irrigation (50 mm–I50); rainfed (I0). Measurements of predawn leaf water potential (ΨPD), stomatal conductance (gs), photosynthetic rate (An), and transpiration rate (E) were made during the final stages of the growth cycle. Data of soil water availability, yield and growth variables, and berries and wine composition were also used. Significant interactions between the effect of soil management and water regime were observed on ΨPD. A water competition effect exerted by the cover crop could be responsible for reduced water loss and carbon assimilation, whenever Spring rain is lower and/or the cover crop biomass development is not controlled. Differences in gs and An observed at midday and late measurements reflect the influence of the daily increase of atmospheric water demand. Stomatal closure of grapevines was less affected in plots of higher soil water storage capacity. The correlation between ΨPD and gs was higher in the midday and late measurements, pointing to the regulation of stomatal response in response to water availability and daily environmental conditions. Principal components analysis (PCA) evidenced an influence of water deficit on metabolic responses that benefit fruit and wine quality. The cluster analysis (CA) revealed that no significant cluster of cases was clearly controlled by soil management or water regime in the first season but, in the second, drier season, significant clustering more irrigation- than soil management-controlled showed that a predominant influence of irrigation should be expected for ‘Tempranillo’ grapevines grown under dry Mediterranean conditions.

Long-term soil quality effects of soil and crop management in organic and conventional arable cropping systems

Improving or maintaining soil health is crucial to support human needs, with the concept of soil quality connecting soil functions and sustainability concerns. In 2019, we assessed soil chemical, physical and biological properties in a long-term crop rotation experiment initiated in 1997 at Foulum, Denmark, with the aim of determining the long-term soil quality effects of the use of cover crops, animal manure, different crop sequences (with or without a legume-based ley) and organic vs conventional management. The concentration of soil organic carbon has been relatively stable across all treatments for 14 years prior to this investigation; in 2019, we found high aggregate stability, porosity, air permeability and pore organization in all treatments. Bulk density, air permeability and pore organization were affected to some extent by soil and crop management, with bulk density being the lowest in the organic treatment without cover crops, which had the most frequent harrowing. Earthworm density was the greatest in the organic system with grass-clover, especially following the ley year, thanks to a combination of high quality plant input and reduced soil disturbance. From a system perspective, none of the treatments investigated represented extremes, and all maintained good soil quality in the long-term. This indicates that long-term management should take into account the combination of different factors affecting soil quality.

Factors Influencing the Effectiveness of Improved Soil Management Practices among Rice Farmers in Abuja

The study examined the socio economic factors influencing the effectiveness of improved soil management practices among rice farmers in the Federal Capital Territory (FCT), Abuja. The study was conducted in Gwagwalada, FCT, Abuja. Two objectives guided the study. The study adopted descriptive research design. Multi stage sampling technique was used to select rice farmers, while a well-structured questionnaire was used for data collection from the 360 rice farmers used for the study. Objectives of the study were achieved using descriptive statistics and logistic regression. The results show that 58.06% of the rice farmers were male, 36.13% were between the ages of 30 and 39years, 47.74% of them were married with 40% having an average of 5 people in their households. Also 61.94% had at most a national certificate of education (NCE). Majority (44.84) of the rice farmers had a farm size of between half a hectare and two hectares. Zero tillage, with a weighted mean score of 2.95, is the most effective soil management practice in the study area, while fertilizer application with a mean score of 3.2 is the most effective fertility practice among the rice farmers in the study area. The result further revealed that with a weighted mean score of 2.5, the respondents agree with the assertion that location of the soil determines the effectiveness of management practices. The result of the logistic regression shows that sex, age, education and farm size all had significant influences on the effectiveness of soil management practices in the study area. It was recommended that manual tillage should be mostly carried out by rice farmer to improve the level of production, use of fertilizer by the farmers to improve the land fertility level should be encouraged, terracing is required to control erosion as most of the rice farm lands are areas that require water which have high tendency of erosion, soil rotation should be practiced where soil is much available to reduce the level of degradation, organic farming should be practiced to reduce the application of chemicals that will constitute hazard to the soil. Keywords: Rice farmers, improved soil management, adoption, effectiveness, zero tillage

The role of soils in regulation of freshwater and coastal water quality.

Water quality regulation is an important ecosystem service function of soil. In this study, the mechanism by which soil regulates water quality was reviewed, and the effects of soil management on water quality were explored. A scientometrics analysis was also conducted to explore the research fields and hotspots of water quality regulation of soil in the past 5 years. This review found that the pollutants entering the soil can be mitigated by precipitation, adsorption and desorption, ion exchange, redox and metabolic decomposition. As an optimal substrate, soil in constructed wetlands has perfect performance in the adsorption and passivation of pollutants such as nitrogen, phosphorus and heavy metals in water, and degradation of pesticides and emerging contaminants. Mangrove wetlands play an important role in coastal zone protection and coastal water quality restoration. However, the excessive application of agricultural chemicals causes soil overload, which leads to the occurrence of agricultural non-point source pollution. Under the dual pressures of climate change and food insecurity in the future, developing environmentally friendly and economically feasible sustainable soil management measures is crucial for maintaining the water purification function of soil by relying on the accurate quantification of soil function based on big data and modelling. This article is part of the theme issue 'The role of soils in delivering Nature's Contributions to People'.

Crop residue displacement by soil inversion: Annelid responses and their impact on carbon and nitrogen dynamics in a lab-based mesocosm study

In the context of sustainable agriculture, a deeper knowledge of the effects of soil management on soil annelids is needed, as they play an important role in many soil processes. In a laboratory mesocosm experiment, we compared the simulated effect of ploughing by inverting the top soil (crop residues at 15 cm depth) to a non-inversion treatment (crop residues on the soil surface) using the soil type Haplic Luvisol. We investigated the response of earthworms and enchytraeids and the consequences for microbial and chemical soil parameters. Four treatments with soil fauna were established by adding: (i) endogeic earthworms (Octolasion cyaneum), (ii) anecic earthworms (Lumbricus terrestris), (iii) a combination of two enchytraeid species (Enchytraeus crypticus and Enchytraeus christenseni) and (iv) having control columns (without annelids). Feeding behaviour of annelids was investigated using isotopic analysis (δ13C, δ15N), and chemical and microbial soil properties were measured. Carbon and nitrogen losses in the form of gas emissions (CO2, N2O) and leachate were recorded during the time of incubation.We found no interactions of soil inversion and annelid addition on chemical and microbial soil properties; these properties were closely related to crop residue placement, indicated by the effect of soil inversion between 0 and 20 cm. Below 20 cm, this effect disappeared. Here, the presence of enchytraeids enhanced soil microbial properties, regardless of soil inversion. Stimulating microbial activity and increasing soil aeration seem to be the most important factors that increase CO2-C emissions in the presence of anecic earthworms. N2O-N emissions were consistently higher (+188%) in the inverted columns. Our results show that regardless of the placement of crop residues, anecic earthworms and enchytraeids fed more on crop residue derived carbon than endogeic earthworms, while endogeic earthworms appeared to avoid feeding at the soil surface. Moreover, it was found that the inversion and the annelid effects did not interact in an experimental setting where soil inversion is carried out in a form without detracting or impairing the annelids directly.

Assessing the Effects of Vineyard Soil Management on Downy and Powdery Mildew Development

Advantages of vineyard cover crops include soil conservation, nutrient and water cycling, and a better growth–yield balance. They naturally promote agro-system biological multifunctionality, soil biocenosis, and biological pest control. However, for the role of cover crops on disease control, there is still a lack of information. We performed a systematic evaluation of the soil management effects on the development of two main pathogens: Plasmopara viticola and Erysiphe necator. Conventional soil tillage was compared to grass and legume cover crops during a three-season trial in the Nurra wine region (Sardinia, Italy). Disease and grapevine development were assessed in relation to the weather, leaf area growth, leaf nitrogen, canopy density, and favorable microclimatic conditions for each disease, to weight their importance on disease susceptibility in each treatment. Higher infection percentages were observed in plots subjected to soil tillage. Disease development was better understood in relation to leaf area, leaf nitrogen, and canopy density. The main role of weather conditions on downy mildew infections was ascertained, yet high canopy sunlight levels reduced disease spread under grass cover. For powdery mildew, leaf nitrogen had a crucial role in disease development under soil tillage, and canopy light and hygrothermal conditions had the most relevant function on disease development in cover-cropped vineyards.

Approximating Soil Organic Carbon Stock in the Eastern Plains of Colombia

In Colombia, the rise of agricultural and pastureland expansion continues to exert increasing pressure on the structure and ecological processes of savannahs in the Eastern Plains. However, the effect of land use change on soil properties is often unknown due to poor access to remote areas. Effective management and conservation of soils requires the development spatial approaches that measure and predict dynamic soil properties such as soil organic carbon (SOC). This study estimates the SOC stock in the Eastern Plains of Colombia, with validation and uncertainty analyses, using legacy data of 653 soil samples. A random forest model of nine environmental covariate layers was used to develop predictions of SOC content. Model validation was determined using the Taylor series method, and root-mean-squared error (RMSE) and mean error (ME) were calculated to assess model performance. We found that the model explained 50.28% of the variation within digital SOC content map. Raster layers of SOC content, bulk density, and coarse rock fragment within the Eastern Plains were used to calculate SOC stock within the region. With uncertainty, SOC stock in the topsoil of the Eastern Plains was 1.2 G t ha−1. We found that SOC content contributed nearly all the uncertainty in the SOC stock predictions, although better determinations of SOC stock can be obtained with the use of a more geomorphological diverse dataset. The digital soil maps developed in this study provide predictions of extant SOC content and stock in the topsoil of the Eastern Plains, important soil information that may provide insight into the development of research, regulatory, and legislative initiatives to conserve and manage this evolving ecosystem.