Improve Soil Physical Properties Research Articles

Analisis Nisbah Dispersi dan Stabilitas Agregat Tanah pada Penggunaan Lahan SisteM agroforestri di Lahan Miring

Agroforestry is a form of conservation principle in maintaining land productivity. The various variations that exist in agroforestry will be able to improve soil physical properties, especially the dispersion ratio and stability of soil aggregates, these physical properties will help in resisting the pressure or force of the falling raindrops. This study aimed to determine the effect of land use by agroforestry systems on the dispersion ratio and stability of soil aggregates on sloping land. The research method used is the descriptive method with sampling done diagonally. There were 3 agroforestry systems (clove-based agroforestry, coffee-based agroforestry, and durian-based agroforestry) which were studied in 3 replications with upstream, middle, and downstream positions. This research was conducted in January-June 2020 in Santoni Village, Kayangan District, North Lombok. Two main parameters were tested, namely the dispersion ratio and the stability of soil aggregates. The results showed that the average value of the ratio of land dispersion indicated by coffee-based agroforestry was 79.85% and the highest was clove-based agroforestry of 91.56%, these values ​​belong to the highly dispersed class. Unlike the case with soil aggregate stability, the highest average soil aggregate stability value was shown in coffee-based agroforestry of 109 and the lowest was clove-based agroforestry of 60. The soil aggregate stability value when interpreted as coffee-based agroforestry was classified as very stable clove-based agroforestry is a relatively stable class. Coffee-based agroforestry is best applied on sloping land so that soil erosion and land productivity can be maintained.

Transition to conservation agriculture: how tillage intensity and covering affect soil physical parameters

Abstract. Conservation agriculture (CA) relies on the following three key practices to improve agricultural sustainability: crop rotation, reduced tillage, and cover crop usage. Despite known soil physical benefits (reduced soil compaction and strength, enhanced soil porosity, and permeability), inconsistent reports on short-term CA results have limited its adoption in the European agroecosystems. To elucidate the short-term effects, a 3-year field experiment was undertaken in the low-lying Venetian plain (northern Italy). Bulk density (BD), penetration resistance (PR), soil hydraulic saturated conductivity, and sorptivity were used to evaluate soil quality obtained by combining three tillage intensities (conventional tillage – CT; minimum tillage – MT; no tillage – NT) with three winter soil coverings (bare soil – BS; tillage radish cover crop – TR; winter wheat cover crop – WW). Among the tillage methods, CT, on average, reduced BD by 4 % (from 1.48 to 1.42 g cm−3) and PR by 3.1 % (from 1.69 to 1.64 MPa) in the 0–30 cm tilled layer. Across the soil profile, reduced tillage coupled with WW improved soil physical properties even below the tilled layer, as evidenced by root-growth-limiting condition reductions (−11 % in BD values, with BD >1.55 g cm−3, and −7 % in PR values, with PR >2.5 MPa). Soil hydraulic measurements confirmed this positive behaviour; NT combined with either BS or WW produced a soil saturated conductivity of 2.12×10-4 m s−1 (4 times that of all other treatments). Likewise, sorptivity increased in NT combined with BS vs. other treatments (3.64×10-4 m s−1 vs. an all-treatment average of 7.98×10-5 m s−1). Our results suggest that, despite the increase in BD and PR due to reduced tillage, the strategy improved soil functioning and particularly soil hydraulic conductivity. In the short term, the WW cover crop moderately increased physical soil parameters, whereas TR had negligible effects. This study demonstrates that, to quantify CA, several soil physical parameters should be monitored.

Corn Yield in Monoculture and Intercropped with Cover Plants and Aggregates Stability

The cultivation of corn intercropped with cover crops has been increasing in the western region of Paraná. However, more technical information about this type of cultivation is needed. Thus, the present study aims to evaluate the yield of corn intercropped with brachiaria and crotalaria and its effect on aggregate stability and soil consistency. The experiment was carried out at the experimental station of Cooperativa Agrícola Mista Rondon (Copagril), in the city of Marechal Cândido Rondon. The experimental design was randomized blocks with 8 replications. There were six treatments for corn cultivation (T1) Corn monoculture (control), (T2) Corn intercropped with Brachiaria (Brachiaria ruzizienses), (T3) Brachiaria in monoculture, (T4) Crotalaria spectabilis (Crotalaria spectabilis) in monoculture, (T5) Corn intercropped with Crotalaria, (T6) Black oats (Avena sativum) in monoculture. Corn yield in intercropping, dry matter added to the soil, aggregate stability and soil consistency were evaluated. The yield of corn intercropped with cover crops was similar to that of corn in monoculture. The cultivation of Brachiaria ruziziensis in monoculture or intercropped with corn produced a large amount of straw and favored soil aggregation. Therefore, the intercropping systems are recommended for the improvement of soil physical properties and the conservation of soil.

Intermittent Deep Tillage on Improving Soil Physical Properties and Crop Performance in an Intensive Cropping System

Soil management practices are important parts of sustainable agriculture. Improving tillage practice is important for alleviating soil degradation and promoting sustainable grain production. A four year field experiment was conducted to examine the effects of deep tillage (DT), incorporated into the minimum tillage (MT), on soil physical properties and crop performance. The field experiments included continuous rotary tillage (RT), continuous DT, and intermittent DT every three years, every two years, and every other year, into RT. The results showed that the introduction of DT into continuous RT reduced the soil bulk density of the 20–30 cm soil layer by 5.6% and reduced nutrient stratification rates by 20–30%, which favored more uniformly distributed soil nutrients in the top soil layer. The root growth for treatments with DT in the deep soil layers (1–1.5 m) was significantly improved, which resulted in a higher soil water depletion. Under deficit irrigation scheduling, the improved root growth and soil water uptake in the deep soil layer improved crop growth and grain production. Overall, a 10.5% increase in yield and 18.3% increase in water productivity were observed when intermittent DT was introduced during the four years. The effects of DT could be maintained for two continuous years. Therefore, it was suggested that after two or three years of RT, DT should be applied to improve soil physical properties and ensure high grain production.

Long term effect of different crop rotations on soil physical properties in a Mollisol

The present study was conducted for the study about the effect of different rotations on physical properties in a Mollisol. The study area was located at Norman E. Borlaug Crop Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar, which lies at 290N latitude, 790 3’ E longitude and 243.84 m above the mean sea level altitude. The crop rotation selected for study were T1 (Rice- Wheat-Fallow) T2 (Rice- Vegetable pea- Summer Rice) T3 (Maize- Wheat- Cowpea) T4 (RiceWheat- Sesbania) T5 (Maize- Toria- Urd) T6 (Rice- Yellow Sarson- Grain Cowpea) T7 (Multi-Cut Sorghum- Barseem + Oat- Maize + Cowpea) T8 (Napier + Fodder cowpea- Barseem- Fodder cowpea) T9 (Basmati rice- Potato- Maize Cob) T10 (Maize- Broccoli- Okra) T11 (fallow (uncultivated land)). The soil sample was collected from 20cm depth for the study of soil physical properties (soil color, soil texture, bulk density, particle density, porosity, and water holding capacity). Among the different crop rotations, T4 treatment was obtained a significantly high value (except bulk density) of soil texture, particle density, porosity, and water holding capacity. T11 (except bulk density) treatment was obtained a significantly lowest value of soil texture, particle density, porosity and water holding capacity Results indicated that soil under Sesbania rotation was found superior with respect to soil physical properties followed by other crop rotation and the uncultivated land. By taking a crop for a long time on same and using chemical fertilizers that are decrease of soil physical properties. Therefore, in this experiment taking different crop rotations. under the different crop rotations, soil physical properties influenced positively and especially the green manure cycle has had the greatest positive impact. According to experimental data concluded that incorporation of green manure crop rotations was effect more positive an effect on soil physical properties. Crop rotations and green manure crops are improved soil physical properties and soil health.

Bio‐tillage improves soil physical properties and maize growth in a compacted Vertisol by cover crops

AbstractBio‐tillage has recently been proposed as a measure to alleviate soil compaction through biopores created by cover crop roots. The objective of this study was to determine the effect of different cover crops on soil physical properties and the succeeding maize (Zea mays L.) growth in compacted soil. Four treatments, including no cover crop as a control (Con), alfalfa (Medicago sativa L.), oilseed rape (Brassica napus L.), and radish and hairy vetch mixture (Raphanus sativus L. and Vicia villosa Roth), were carried out under both compacted and noncompacted soil conditions. Soil physical properties, such as the volumetric soil water content (SWC), bulk density, saturated hydraulic conductivity (Ks) and air permeability at water potential of −60 hPa (Ka60), and maize root characteristics and yield were measured. The cover crops did not affect the soil bulk density but significantly decreased the SWC in both the compacted and noncompacted soils relative to the Con treatment. The alfalfa treatment presented significantly higher Ks in the noncompacted soil and Ka60 in both the compacted and noncompacted soils than the Con treatment in the soil layer depth of 20–50 cm. The three cover crop treatments improved the maize root biomass density (173.2% for 2018 and 35.6% for 2019) and root length density (50.9% for 2018 and 51.8% for 2019) relative to the Con treatment in the soil layer depth of 10–70 cm in 2018 and soil layer depth of 10–50 cm in 2019 in the compacted soil rather than in the noncompacted soil. Compared with the Con treatment, the radish mixed with hairy vetch treatment in 2018 and the oilseed rape treatment in 2019 significantly enhanced the maize yield in the compacted soil. Our results suggest that alfalfa is the best crop for improving air permeability; however, the oilseed rape and mixture of radish and hairy vetch lead to better maize growth in the compacted soil. Bio‐tillage using cover crops is effective in alleviating soil compaction.

Effect of field pea (Pisum sativum subsp. arvense (L.) Asch.) and pea-oat (Avena sativa L.) biculture cover crops on high tunnel vegetable under organic production system

In general, adaptation of cover cropping in crop rotation practices to organic tunnels by methods supporting soil health and quality has not yet been fully optimized. Effect of field pea and pea-oat cover crops to soil physicochemical properties and cash crop quality was assessed in an organic high tunnel in southern Poland in 2016–2017, with the following planting sequence: spring cover crops/tomato/romaine lettuce/green bean/iceberg lettuce. The sole pea produced a lower aboveground biomass (3.06 t ha−1) than the pea-oat mixture (4.17 t ha−1), and the N content in their biomass was 155 kg N ha−1 and 136 kg N ha−1, respectively. The results indicated that a high residue input from cover crops was important for soil organic carbon stock, for retaining plant-available N in organic matter, and for improving soil physical properties, especially wet aggregate stability. We observed an increase in soil pH and the availability of some mineral nutrients in the soil under cover crop treatments, especially Ca, Mg, K, and P. N uptake by the subsequent cash crop significantly (p ≤ 0.05) increased with pea than with pea-oat biculture, and in the green manure formula than with the mulch treatment. Early spring cover cropping depressed the subsequent tomato yield, but enhanced green bean yield in the second year of cropping.

REGE (Recycle Vegetable Waste): Pemberdayaan Limbah Sayur Menjadi Pupuk Organik Padat dan Cair Ramah Lingkungan di Pasar Koto Baru

Compost has some advantages, improving soil physical properties, chemical properties, and biological properties. It happens because its characteristics contain nutrients in varying types and amounts depending on the original material, provide nutrients slowly (slow release) and in limited quantities, and have the main function of improving soil fertility and health. The pile of organic waste from the Koto Baru market directly impacts the environment to their community. This Community Service Program aims to increase the knowledge and skills of target communities about processing vegetable waste from the Koto Baru market into the solid and liquid-friendly environment of organic fertilizers. The target people of this activity were PKK Jorong Subarang Nagari Koto Baru women in particular and people who wrote Jorong Subarang Nagari Koto Baru. The methods used in this service were socialization of the processing of vegetable waste from the Koto Baru market into the solid and liquid-solid and liquid friendly environment of organic fertilizers, distribution of practical manuals for assembling tools for making solid and liquid organic fertilizer from vegetable waste, distributing initial questionnaires to online socialization. This activity had positive impacts on these PKK women, including providing knowledge of PKK women about the use of organic vegetable waste from the Koto Baru market to become a POP friendly environment and POC, the dissemination of information on the use of vegetable waste from the Koto Baru market became a solid and liquid friendly environmental of organic fertilizer in Jorong Subarang Nagari Koto Baru, Tanah Datar Regency.

Effects of subsoiling tillage on structure, permeability, and crop yields on compacted Solonetzic and Chernozemic dryland soils in Western Canada

Compaction induced by field wheel traffic and dense layers in the subsoil may adversely alter soil structure, impede soil aeration, restrict water infiltration and nutrient uptake, and inhibit plant root development, negatively affecting plant yields. Reclaiming compacted Chernozemic and Solonetzic soils with hardpan B horizons may be possible through subsoiling operations to loosen the soil to depth, e.g. ~0.30 m. The objective of this study was to evaluate the effect of subsoiling on soil physical properties and plant yield in wheel traffic compacted and non-compacted Chernozemic and Solonetzic soils in southern Saskatchewan Canada. Subsoiling increased air permeability in the compacted Chernozemic soil from 4.5x10-7 m sec-1 to 2.9x10-6 m sec-1. In the compacted Solonetzic soil, subsoiling significantly decreased soil cone index to 1579 kPa compared to 2376 kPa in the non-subsoiled treatment. Crop yields (hard red spring wheat, dry peas) in the two years following the treatment were similar among tillage and compaction treatments in the Chernozemic soil. However, subsoiling of the compacted Solonetzic soil resulted in a seed yield increase of canola of ~ 1000 kg ha-1 in the first year of study and no treatment effect in the second year when wheat was grown. Overall, subsoiling of the compacted soils tended to improve soil physical properties, especially in the Solonetzic soils.

Influence of palm oil mills effluent (POME) sludge vermicomposting on soil physicochemical properties and Zea mays growth performances

Discharging the palm oil mill effluents (POME) might result in environmental pollution, thus the POME wastes that had high total solids, abundant in oil palm mills, potential to be utilized as an organic amendment, vermicompost or treated POME sludge (TPS). The objectives of this study are to determine the best treatment effect of organic amendments and Zea mays growth performances, and to analyse the soil physicochemical properties after application of treatments after harvesting. This experiment was carried out in Randomized Completely Block Design (RCBD) with 4 treatments and 6 replications. The treatments consisted of; treatment 1: Control, treatment 2: 2 kg FVC, treatment 3: 2 kg TPS and treatment 4: 1 kg FVC and 1 kg TPS. Based on the result, 2 kg FVC (T2) treatment showed significant improvement in soil physical properties and soil shear strength. Cation exchange capacity (CEC), nutrients availability and and Zea mays growth performances were also improved in this experiment. For shear strength analysis, T4 treatment showed high normal stress at 319.4 kN/m2. In conclusion, FVC organic fertilizer and mixed FVC and TPS indicated the best amendment in improving soil physicochemical and enhanced Zea mays growth performance and it is cost effective and environmentally friendly.

Improving Soil Physical Properties and Cassava Productivity Through Organic Fertilizers Management in the Southern Cameroon

Improving Soil Physical Properties and Cassava Productivity Through Organic Fertilizers Management in the Southern Cameroon

Spontaneous Vegetation as an Alternative to Cover Crops in Olive Orchards Reduces Water Erosion and Improves Soil Physical Properties Under Tropical Conditions

Spontaneous Vegetation as an Alternative to Cover Crops in Olive Orchards Reduces Water Erosion and Improves Soil Physical Properties Under Tropical Conditions

The residual effect of soil amendments application on physical sandy soil properties and first ratoon sugarcane (Saccharum officinarum L.)

Sugarcane cultivation in sandy soil is quite difficult because the sandy soil properties are less suitable for this crop. Soil amendment application might be important as a growth medium for sugarcane. This study aimed to improve the physical properties of sand-texture soil due to the residue of soil amendments application and their effect on first ratoon sugarcane. The study was arranged in a randomized block design with ten treatments and three replication. The treatment was soil amendments residue which had been applied in 2013 includes 10 t ha−1 of single soil amendment: sugarcane trash biochar (STB), sugarcane trash compost (STC), boiler ash (BA), cattle manure (CM); and 5+5 t ha−1 of combinations: STB+STC, STB+CM; BA+STC, BA+CM, BA+filter cake (FC), and control. The results showed that the residue of soil amendment at 11 months after ratooning significantly improved soil physical properties such as aggregate stability, bulk density, total porosity, and available water content. The residue treatments of STB, CM, STB+CM, gave better effect on soil properties and increased growth, but they did not significantly increase the yield of the first ratoon sugarcane. Therefore, further research is needed with a dose of soil amendments >10 t ha−1 in combination with nutrient treatments.

Surface morphology properties of biochar feedstock for soil amendment

A soil amendment is any material added to a soil to improve soil physical properties, support plant growth, improve soil fertility, organic matter, and water holding capacity, improve soil chemical and biological properties. Biochar is an organic amendment that improve soil fertility, mitigates climate change, and effectively keeps nutrients and available to plants. The chemical and physical properties of the biochar are important to know the suitable applications of biochar. The chemical and physical properties of the biochar are depending on the process and biomass feedstock. The research aimed to find out the kind of biomass feedstock for biochar as a soil amendment. The biochar feedstock was evaluated using scanning electron microscopy (SEM) and electron dispersive X-ray (EDX) analysis and can predicting possible uses for the biochars. The result showed that the biochar surface morphology properties were influenced by the feedstock types and pyrolysis temperature. The pores development and mineral contents in coconut shell biochar are the most suitable for soil amendment.

Integrated Use of Phosphatic Fertilizer and Farm Manure on Soil Physical Properties and Maize Yield

Soil fertility, one of the important determinants of agricultural productivity, is generally thought to be supplemented through the application of nutrients mainly through inorganic fertilizers and organic amendments. The physical health of the soil creating suitable environment for the availability and uptake of these nutrients is generally ignored. The present study was aims to characterize the soil physical environment in relation to integrated application of farm manure (FM) and inorganic fertilizer in hybrid maize (Zea mays L.). A Field experiment was conducted at Research Area of Institute of Soil Environmental Sciences, University of Agriculture Faisalabad to evaluate the impact of different levels of DAP fertilizer @ 70:80:90 kg ha-1 in combination with FM @ 0, 5, 10 Mg ha-1 to check the soil physical properties as well as yield of hybrid maize. The experimental design was RCBD under factorial structure with 9 treatments replicated thrice. Crop was harvested at maturity and taking observations like physical parameters (Bulk density, porosity, infiltration rate, field saturated hydraulic conductivity, soil strength) and yield parameters (1000 grain weight, plant height, total grain yield) following standard procedures. Results showed that integrated use of farm manure and phosphorus rates significantly affect the plant height, grain yield of maize. Farm maure and phosphorus levels also increased soil porosity and soil hydraulic conductivity. But it reduced the soil bulk density and soil strength. So to improve soil physical properties, to gain substantial yield of maize phosphorus rates applied in a planned manner rather than excessive use and effects of farm manure should also be kept under consideration.

Soil Physical Properties and Root Growth of Pearl Millet as Affected by Ridge Tillage and Farmyard Manure

Ridge tillage (RT) and organic manure management are among promising agronomic practices for conserving soil moisture and improving soil physical environment in arid and semiarid rain-fed areas. The studies were conducted during the year 2020 farming season with two soil types from northeastern part of Nigeria to compare the relative efficacy of RT with and without organic manure in improving soil physical properties and root growth of millet under rain-fed semi-arid condition. The effects of the RT treatments in combination with organic manure were compared to the conventional flat-bed treatment (control, FB). The soil types chosen for the study were sandy loam soil located at the University of Maiduguri (Unimaid) and sandy clay loam located at Alakaramti village, respectively. The other land configuration and manure treatments compared were: open-ridge (OR), tied-ridge (TR), flat bed + manure (FBM), open-ridge + manure (ORM), and tied-ridge + manure (TRM) each laid out in randomized complete block design with four replicates. The combination of RT (open or tied) plus organic manure (ORM & TRM) performed better in terms of all measured parameters: bulk density (Bd), porosity (Tp), mean weight diameter (MWD), soil water content (SWC) and root growth as measured with root mass density (RMD) than the bare ridge-tilled (OR & TR) or flat bed with manure (FBM) and without manure (FB) treatments, irrespective of differences in soil type. The improvement in soil condition resulting from combining the practices of RT with organic manure application as reflected by reduced Bd, increased Tp, and higher profile SWC has enhanced millet root growth under the water limited rain-fed farming system of the study area. In regions like northeast Nigeria where low and variable rainfall often limits crop production, the practice of combining RT(open or tied) with organic matter input could be recommended as an optimal agronomic practice for improving drought resilience of crops like millet.

Long-Term Integrated Nutrient Management in the Maize–Wheat Cropping System in Alluvial Soils of North-Western India: Influence on Soil Organic Carbon, Microbial Activity and Nutrient Status

Integrated nutrient management (INM) is a widely recognized tool to ensure sustainable crop productivity while preserving soil fertility. The addition of organic manures in soil has been evidenced to improve soil characteristics, in addition to improving nutrient availability. The soil samples, with five treatment combinations of chemical fertilizers with farmyard manure (FYM), were collected from a 17-year-old field experiment conducted at PAU, Ludhiana to investigate the effect of INM on the buildup of organic carbon (OC), microbial community, soil nutrient status and improvement in soil physical properties under the maize–wheat cropping system. The INM technique enhanced the OC content (0.44 to 0.66%), available N (152.8 to 164.9 kg ha−1), P (22.8 to 31.4 kg ha−1) and K (140.6 to 168.0 kg ha−1) after 17 years. The DTPA-extractable and total micronutrients (Zn, Cu, Fe, and Mn) status also improved significantly with FYM supplementation. The organic source, coupled with inorganic fertilizers, improved the water holding capacity, total porosity, soil respiration, microbial biomass C, microbial biomass N, and potentially mineralizable N. However, pH, EC, and bulk density of soil decreased with the addition of FYM, coupled with chemical fertilizers.

The Effect of Composting Campus Litter Granules and Inorganic Fertilizers on the Improvement of Soil Physical Properties and Corn Yield (Zea mays L.) In Inceptisol

The addition of organic matter is done to overcome the problems that occur in acid soils such as inceptisols. The aim of the research was to develop organic fertilizer enriched in granular form from campus litter compost to improve soil physical properties and maize yield in Inceptisols. The treatments consisted of: no fertilizer (KGSK1), 8 t ha-1 granule compost (KGSK2), inorganic fertilizer (Urea, SP-36, and KCl) recommended dose (KGSK3), inorganic fertilizer + 8 t ha- granule compost (KGSK4 ), x dose of inorganic fertilizer + compost granule (8 t ha-1) (KGSK5), 2 times dose of inorganic fertilizer + compost granule 8 t ha-1 (KGSK6), x dose of inorganic fertilizer + compost granule 12 t ha- 1 (KGSK7) and 2 times the dose of inorganic fertilizer + compost 4 t ha (KGSK8). The study was designed using a randomized block design with three replications. The results of the study found that the provision of enriched campus litter granules, either applied singly or in combination with inorganic fertilizers, had a significant effect on improving soil physical properties, namely soil volume weight, soil specific gravity, soil porosity, fast drainage pores, slow drainage pores, water pores. available, and unavailable pore water were 0.90 g cm-3, 2.30 g cm-3, 7.77%, 23.54%, 8.83%, 11.62%, and 249.17%, and the yield of dry shelled corn was 7.85 tons ha- 1.Keywords: Granular compost, Corn, Inceptisol, inorganic fertilizer

Effectiveness of cowpea (Vigna unguiculata L.) living mulch on weed suppression and yield of maize (Zea mays L.)

Abstract Weed control plays a vital role in achieving higher maize yield. We tested the hypothesis that interseeding cowpea as living mulch with maize will reduce biomass and diversity of weeds, and improve soil physical properties and maize yield. In 2017/2018 cropping seasons, a 2 × 4 factorial experiment was laid in a randomized complete block design with three replications at the Savelugu Municipality of Northern Ghana. The factorial treatment consisted of three cowpea varieties interseeded with two maize genotypes and a control (maize with no living mulch). Our result showed that, in both seasons, weed biomass and diversity, soil temperature, and grain yield were significantly (p < 0.05) higher in control plots than in cowpea living mulch plots at all growth stages of both maize varieties. However, maize growth was not affected by weeds at tasseling. We established that cowpea varieties as living mulch in maize cropping have similar effect on soil moisture and temperature but have varying degrees of suppressing weeds and improving maize yield. The cowpea living mulch had weed biomass of 0.5 t ha−1 compared to 2.6 t ha−1 in the control. In addition, living mulch plots had maize grain of 2 t ha−1 and stover yield of 3 t ha−1 compared to 0.98 and 2 t ha−1 respectively in the control. In conclusion, choosing the appropriate time for intercropping living mulches and selection of plant species (growth and canopy cover) for living mulch are essential in suppressing growth of weeds.

Functional root trait‐based classification of cover crops to improve soil physical properties

AbstractCover crop use is a well‐established soil conservation technique and has been proven effective for erosion control and soil remediation in many arable systems. Whereas the obvious protection mechanism of cover crops occurs through the canopy, plant roots perform multiple functions. It is important to consider the soil functions delivered by different root systems in order to increase the uptake of cover crops for sustainable soil and water management. A classification of cover crop root systems up to 0.6 m deep based on functional traits will allow us to better study their potential role in soil bio‐engineering, soil structural improvements for hydrological services and soil resource protection. This was a glasshouse experiment, using large 1‐m3 containers filled with loam soil, loose topsoil and compacted subsoil, in which seven cover crop species (oat, rye, buckwheat, vetch, radish, mustard, phacelia) were grown for 90 days. Root cores were taken at the end of the experiment, washed and imaged to determine root traits (total root length density, average root diameter, root specific length and root surface area) for both the topsoil and subsoil layers. Root identity was determined from a distinctive combination of single root traits and related to three soil functional variables, representing soil structural improvement, runoff mitigation and erosion control. The results showed that total root length and root surface area correlate well with aggregate stability and soil macroporosity. Buckwheat, mustard and rye had significantly greater aggregate stability, as well as 10, 8 and 7% greater microporosity, respectively, at the interface with the compacted layer when compared to the control bare soil. Furthermore, average root diameter negatively correlated with soil macroporosity, indicating that cover crops with a fine root system are more beneficial for creating pore‐space than those with thicker taproots. Selecting cover crop species with the right root traits is therefore crucial to improve soil health.Highlights Roots of cover crops are a largely unexplored frontier for bio‐engineering of agricultural soils. Combinations of root traits were identified that most improve soil characteristics. Cover crops with finer root systems were better at enhancing porosity. Root length and surface area were most important for enhancing soil structure.