Evaluation Of Soil Quality Research Articles

Determination of plant-parasitic nematode fauna and evaluation of soil quality in apple orchards of Çanakkale province (Türkiye)

Determination of plant-parasitic nematode fauna and evaluation of soil quality in apple orchards of Çanakkale province (Türkiye)

A holistic approach for the evaluation of iron nanoparticles on maize plants and earthworms in natural soil.

There is a debate about the implications of the effect of nanoparticles or nanomaterials on edible plants and soil organisms. Earthworms have been used to evaluate soil quality, reproduction, survival, and other biochemical parameters when organisms are exposed to nanomaterials. Most studies have been performed in laboratory settings, and little has been studied under realistic conditions, especially when earthworms and corn plants share the same natural soil and organic matter space. The objective of this research was to evaluate concentrations of 10, 100, 200, 400, and 800mgkg-1 of iron nanoparticles (Fe NPs, combination of magnetite [Fe3O4] and hematite [α-Fe2O3]) on the growth and development of maize plants (Zea mays L.), and of the reproduction parameters of Eisenia fetida during 110 days of exposure. The results demonstrated that concentrations of 100 and 400mgkg-1 of Fe NPs positively changed some morphological, photosynthetic, and yield parameters in maize crops. Unexpectedly, concentrations of 400 and 800mgkg-1 decreased earthworm population but, at the same time, increased the number of juveniles. With this holistic approach experiment, it was demonstrated that the use of Fe nanoparticles as a biostimulant can promote corn yield parameters, but at the same time it impacts the reproductive capacity of the earthworms. However, it is necessary to explore the long-term effect of the proposed nanomaterials in agriculture to rule out risks or ecological implications in agricultural systems.

Soil quality assessment in agricultural lands of an industrializing region of India.

Soil degradation due to industrialization is a growing global concern, emphasizing the importance of evaluating soil quality near industrial zones to ensure food security, environmental sustainability, and public health. This study compares soil quality across five industrial sites, including foundries, electroplating, paper mills, textile mills, and quarries and cement industries, in the Coimbatore district. Soil samples were collected via a purposive sampling approach from nearby agricultural fields via a 500 m2 grid. The soil quality was assessed by including all the soil parameters as soil quality indicators via principal component analysis (PCA) and correlation studies with a minimum data set followed by linear scoring and the weighted additive method. The soil quality was ranked as follows: reference soils (0.752) > foundry industrial sites (0.591) > quarry and cement industrial sites (0.554) > paper mill sites (0.552) > textile and dyeing industrial sites (0.500) > electroroplating industrial sites (0.482). The findings reveal that industrial activities significantly compromise soil quality in adjacent agricultural areas, with varying levels of impact.

Evaluation of Soil Quality and Health Sustainability of Cocoa (Theobroma Cacao) Crop in Two Production Systems, Morona, Santiago, Ecuador

The productive evaluation of cocoa in this research is proposed through an assessment of soil quality and crop health in an organic production system (SPO) Taisha canton and a conventional production system (SPCv) Morona canton. Methodology: Altieri and Nicholls establish a diagnosis of chemical, physical, biological and health indicators, with weightings high (10), medium (5) and low (1). Results: SPO soil quality, reflects weights 10 (high) for ammonium ion, zinc, copper, iron, manganese, moisture retention, biological activity, compaction, apparent density, residue status, color, organic matter, root development, erosion incidence; 5 (medium) potassium, phosphorus, calcium, sulfur, pH, texture; 1 (low) magnesium, boron, topsoil depth, for crop health values ​​of 10 (high) appearance, crop growth, stress resistance or tolerance, weed competition, agrosilvopastoral system, plant diversity and management system, 5 (medium) potential yield, incidence of pests and diseases. The SPCv soil quality presented a weighting of 10 (high) for nitrogen, zinc, copper, iron, biological activity, compaction, bulk density, color, organic matter, root development, erosion incidence; 5 (medium) manganese, pH, texture, moisture retention, residue status; 1 (low) potassium, phosphorus, calcium, magnesium, sulfur, boron, topsoil depth; crop health 10 (high) crop appearance and growth, stress resistance or tolerance, weed competition, agrosilvopastoral system, plant diversity, management system, potential yield, 5 (medium) incidence of pests and diseases, 1 (low) surrounding natural diversity. Conclusions: The SPO for soil quality: 7.41 and for crop health: 7.59 weighted as sustainable, while the SPCv for soil quality: 6 and crop health: 6.76, resulting in a moderately sustainable production system.

Evaluation of Soil Quality in Different Bletilla striata Agroforestry Systems in Eastern China

Agroforestry is being promoted as a feasible land use management to improve understory economic benefits. However, there are few studies on species selection and the comprehensive evaluation of soil quality change in rhizoma bletillae (Bletilla striata) agroforestry systems. The soil quality index (SQI) and minimum dataset (MDS) methods can reflect the overall condition and were effective tools for understanding different cultivation systems. In this study, we evaluated the soil quality of four cultivation models (including three agroforestry systems: PeB, moso bamboo (Phyllostachys edulis)–rhizoma bletillae; PoB, plane trees (Platanus orientali)–rhizoma bletillae; CcB, pecan trees (Carya cathayensis)–rhizoma bletillae; and CK, rhizoma bletillae monoculture. The total dataset (TDS) consisted of 15 soil parameters containing physical, chemical, and biological characteristics. The results showed that soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) were finally selected and established as the MDS. Agroforestry could significantly influence soil quality. Compared with CK, the SQI in CcB significantly increased and decreased in PeB and PoB. Soil water content (SWC), nitrate nitrogen (NO3−-N), dissolved organic carbon (DOC), SOC, TN, and TP contents were higher in CcB than in the other cultivation models. Based on various soil indicators and SQI analysis, the CcB was the best in improving soil quality. These findings showed that the soil quality index based on the MDS can be used as an effective indicator for agroforestry systems selection. It provides theoretical guidance for the practice of bionic cultivation and the sustainable management of rhizoma bletillae.

Enhancing Soil Quality and Maize Yield with the Combination of Acacia-Biochar, NPK Fertilizer and Compost

<p style="text-align:justify; margin-bottom:13px"><span style="font-size:11pt"><span style="text-justify:inter-ideograph"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-GB" style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:"Times New Roman",serif">Pakistan's agricultural soils exhibit a high tendency for leaching, low quantities of organic matter, and minimal microbial activity. The situation is aggravated by human activities such as bush burning, mining, sand extraction, and ongoing conventional methods of farming. These methods, together with the naturally low amounts of organic matter, result in the soil being deprived of essential nutrients. These nutrients are necessary for the optimal growth and yield of crops. Enhancing crop production such as maize and other crops on nutrient-deficient soils has the potential to improve household food security in Pakistan, necessitating the implementation of appropriate measures.</span></span></span> <span lang="EN-GB" style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:"Times New Roman",serif">Various techniques have been devised to mitigate the deleterious impacts on plants. The use of biochar, an organic substance produced through pyrolysis with limited oxygen supply, as a soil amendment is currently attracting significant attention globally.</span></span></span> <span lang="EN-GB" style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:"Times New Roman",serif">This study aimed to assess the effectiveness of a mixture of Acacia-biochar, NPK fertilizer, and compost in improving soil quality and boosting yields of crops.</span></span></span> <span lang="EN-GB" style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:"Times New Roman",serif">The first variable examined in the study was the biochar dosage, which was divided into four levels: no biochar, a biochar dosage of 5, 10, and 15 t ha<sup>-1</sup>. Additionally, it is important to take into account the selection of fertilizer, which consists of four different types: non-fertilizer, NPK, compost, and NPK + compost. The results showed that applying biochar at a rate of 10 t ha<sup>-1</sup>, along with NPK + compost, improved the availability of phosphorus and potassium, and significantly enhanced soil quality, as indicated by a soil quality rating value of 18. Applying a rate of 10 t ha<sup>-1</sup> of biochar, along with NPK + compost, led to the highest dry weight of seed maize, achieving 12.80 t ha<sup>-1</sup>. This represents a 40% augmentation in relation to the conditions without biochar and with the addition of NPK + compost. When the seed maize is weighed without any moisture content, the yield of 12.80 t ha<sup>-1</sup> results in the highest level of efficient agronomic value, which is 120.31%. Additionally, the feasibility value for growing maize in drylands is 1.28.</span></span></span></span></span></span></span></p>

Croplands Quality Evaluation of Whole Tillage Layer Based on the Minimum Data Set in Jilin Province, China

The aim of this study is to accurately evaluate the quality characteristics of whole tillage cropland and deepen the knowledge of sub-tillage soil quality evaluation in Jilin Province, China. In this study, top-tillage and sub-tillage soil samples were collected from 185 maize continuous cropping areas in Jilin Province, and 12 physicochemical indexes (pH, cation exchange capacity (CEC), soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), available potassium (AK), sand, silt, and clay) were used to evaluate the whole tillage layer soil quality index (SQI). The results showed that the whole tillage soil physicochemical indexes in Jilin Province were generally above the moderate level, and nutrient contents increased from West to East among the regions. The minimum data set SQI (SQI-MDS) of the top-tillage and sub-tillage layers were 0.22–0.98 (0.46) and 0.23–0.93 (0.55), respectively. The suitable ranges of MDS parameters for reasonable tillage layers were as follows: top-tillage layer SOM ≥ 34.5 g kg−1, 31.5% ≤ sand ≤ 53.5%, AP ≥ 32.1 mg kg−1, and TK ≥ 15.18 g kg−1; sub-tillage layer 31.3% ≤ sand ≤ 51.2%, TN ≥ 1.48 g kg−1, 6.4 ≤ pH ≤ 7.1, and AK ≥ 157.6 mg kg−1. In summary, the SQI and evaluation indexes of the top-tillage and sub-tillage layers in different ecological zones are varied. It is necessary to adjust the evaluation index thresholds in combination with the actual conditions to establish a more accurate evaluation index system of the whole tillage soil quality.

Effects of plastic film mulching on soil microbial carbon metabolic activity and functional diversity at different maize growth stages in cool, semi-arid regions.

Plastic film mulching has been widely used to enhance soil hydrothermal conditions and increase crop yields in cool, semi-arid areas. However, its impact on soil microbial carbon metabolic activity and functional diversity during plant growth remains unclear despite their important roles in nutrient cycling and soil quality evaluation. This study used the Biolog EcoPlate technique to investigate the dynamics and driving factors of soil microbial carbon metabolic activity and functional diversity at different maize growth stages following plastic film mulching. The results revealed that film mulching significantly increased microbial carbon metabolic activities [represented by average well color development (AWCD)] by 300% at the seedling stage and by 26.8% at maturity but decreased it by 47.4% at the flowering stage compared to the control (without mulching). A similar trend was observed for the microbial functional diversity index. Redundancy analysis identified soil moisture (SM), soil temperature (ST), dissolved organic carbon (DOC), microbial biomass carbon (MBC), and bacteria amounts as the primary factors influencing changes in soil microbial carbon source utilization. The mulch treatment significantly increased SM at all growth stages, while its warming effect disappeared at the flowering stage. Soil DOC, MBC, and bacterial populations were notably higher under mulching at the seedling and maturity stages but lower at the flowering stage. Pearson correlation analysis showed that changes in SM, ST, DOC, MBC, and bacterial populations positively correlated with the utilization of all carbon source classes, AWCD, and functional diversity indexes after film mulching. Furthermore, maize grain yield and water use efficiency increased by 142 and 129%, respectively, following film mulching. In conclusion, plastic film mulching enhanced soil microbial carbon metabolic activity and functional diversity at the seedling and maturity stages, improving crop yields in cool, semi-arid areas. Furthermore, the decrease in soil carbon metabolic capacity at flowering stage highlights that supplementing soil carbon sources should be considered after continuous film mulching to sustain or enhance farmland productivity and soil quality.

Evaluating soil quality and carbon storage in Western Ghats Forests, Karnataka, India, for sustainable forest management.

Monitoring soil quality index (SQI) and soil organic carbon (SOC) stock status of the Western Ghats (WG) forests in India is crucial for providing vital ecosystem services alongside sustainable forest management practices. However, comprehensive profile data on SQI and SOC stock across different forest types under WG forests are limited. The study evaluated SQI and SOC stock under three forest types, i.e. tropical wet evergreen (TWE), tropical semi-evergreen (TSE), and tropical moist deciduous (TMD) across WG in Karnataka. SQI was assessed using principal component analysis with two indexing approaches and scoring methodologies, with weightage indexing through nonlinear scoring functions (NLSF) showing superiority over other methodologies. TMD forests exhibited the highest SQI, followed by TWE and TSE, while the lowest was observed in Rippon Pet RF (0.36 surface, 0.28 control section), primarily due to limitations in organic carbon and clay content. SOC stock mirrored SQI trends (TMD > TWE > TSE), with the highest values in Kollegal RF (339.3 MG ha-1) and lowest in Rippon Pet RF (102.5 MG ha-1). Although SOC and SQI were established to be ideal indicators for dynamic ecosystem services (ESs), high OC content in surface soils of Poomale NF induces pedogenic acidification and Al toxicities, indicating potential forest soil degradation. Significant correlation with control section SQI and SOC (p < 0.05) emphasises monitoring subsurface soil status to identify soil degradation, sustainable forestry practices, and complex ESs in forest systems.

Soil health evaluation of non-grain cultivated land: A case study of Dongwu Town, Ningbo City, Zhejiang Province, China

Non-grain utilization of cultivated land threatens farmland ecological environment and soil health, which restricts grain production. To identify the key obstacle factors of cultivated soil under non-grain utilization, explore the changes of soil quality and function, and evaluate the effects of non-grain utilization on the health of farmland soil, we evaluated soil health of farmland under different non-grain utilization types (vegetables, bamboo-abandoned, nursery-grown plant-abandoned, nursery-grown plant-rice) by soil quality index and soil multifunctionality index method combined with sensitivity and resistance approaches. The results showed that soil organic carbon and total nitrogen (TN) in the bamboo-abandoned soil were 95.3%, 66.7%, 65.7% and 82.6%, 57.0%, 59.5% of those under vegetables, nursery-grown plant-abandoned and nursery-grown plant-rice treatments, respectively. The electrical conductivity of vegetable soil was 2.2-2.5 times that of other soils of non-grain cultivated land. Total phosphorus and nitrate nitrogen were 1.8-2.0 times and 3.5-5.5 times of other soils of non-grain cultivated land, respectively. Among different non-grain utilization types, soil quality index and soil multifunctionality index of vegetable soil were the highest. Soil quality index and soil multifunctionality index decreased significantly in bamboo-abandoned (50.2% and 22.7%), nursery-grown plant-abandoned (38.3% and 14.4%) and nursery-grown plant-rice (27.7% and 8.5%) treatments, compared with that of vegetable soil. Random forest model analysis showed that available potassium and available nitrogen (AN) were the key factors affecting soil quality index. TN, cellulase and xylanase activities that related to soil C cycle were the key factors affecting soil multifunctionality index. In addition, available phosphorus, AN, TN and enzyme activity were sensitive indices to soil change in non-grain cultivated land. By comprehensively evaluating soil quality of non-grain cultivated land, we identified the key obstacle factors and provide a theoretical basis for the healthy soil cultivation and sustainable utilization of non-grain cultivated land.

Reducing Nitrogen Application Rates and Straw Mulching Can Alleviate Greenhouse Gas Emissions from Wheat Field Soil and Improve Soil Quality

Sustainable agriculture faces challenges balancing the need for increasing crop production with environmental protection. Straw mulching is widely used to improve crop productivity, while reducing nitrogen application is an effective strategy to reduce greenhouse gas (GHG) emissions. However, the comprehensive evaluation of soil properties, GHG emissions, and soil quality under straw mulching conditions with different N application rates has not been extensively studied, especially in the Loess Plateau region of Central Gansu. Therefore, a two-year field experiment was conducted, involving two tillage practices (CT: conventional tillage, CTS: conventional tillage + straw mulching) and three fertilization levels (LN: low nitrogen fertilizer, 55 kg N ha−1; MN: medium nitrogen fertilizer, 110 kg N ha−1 HN: high nitrogen fertilizer, 220 kg N ha−1). Based on the greenhouse gas emission intensity (GHGI), the minimum data set (MDS) was constructed by principal component analysis, correlation analysis, and Norm value, and the weighted index method was applied to comprehensively evaluate the soil quality. Our results showed that compared with CT, CTS significantly increased crop yields and improved the content of soil nutrients, and it was more effective when applying moderate amounts of nitrogen fertilizer. Wheat field soil behaves as a nitrous oxide (N2O) emission source and a methane (CH4) absorption sink. CTS–MN and CTS–LN reduced N2O emission by 52.95–87.76%, increased total CH4 uptake by 16.69–43.60%, and slowed down global warming potential (GWP) by 35.70–48.17% compared with CTS–HN in 2021–2022. They also reduced GHGI. Furthermore, CTS enhanced soil quality at different nitrogen application levels compared with CT, with CTS–MN exhibiting the highest Soil Quality Index (SQI) over the two years. Consequently, considering both economic and environmental benefits, CTS–MN can be regarded as a key practice for the sustainable development of agroecosystems in the Loess Plateau region of Central Gansu.

Soil Quality Evaluation and Analysis of Driving Factors of Pinus tabuliformis in Loess Hilly Areas

The selection of suitable tree species and the reasonable allocation of planting areas are important measures for improving soil quality. To evaluate the soil quality (SQ) and its driving factors of Pinus tabuliformis forests in loess hilly areas where forestry ecological projects, such as returning farmland to forest (grass), have been implemented, this study selected P. tabuliformis forests with different restoration years (1a, 6a, 11a, 18a, and 22a) in Wuqi County and used grassland before afforestation (PRG) and abandoned grassland (AG) with 22 years as controls. In this study, soil physicochemical indices, soil fauna indices, and herbaceous plant indices obtained via principal component analysis were used to establish a soil quality evaluation model via the fuzzy comprehensive evaluation method to comprehensively evaluate SQ. Structural equation modeling (SEM) was used to identify the key factors affecting the SQ of P. tabuliformis forests. The goal was to create a model that could effectively evaluate the SQ while considering all relevant factors. The findings of the study showed that: (1) by performing a principal component analysis on the 27 indicator factors, the first six principal components had eigenvalues &gt; 1, and the cumulative contribution rate was 90.028%, effectively encompassing the information of the original variables. (2) The highest soil quality index (SQI) was 0.592 (p &lt; 0.05) in the restored 6a P. tabuliformis forest, whereas the lowest SQI was 0.323 in the restored 1a P. tabuliformis forest. As the number of years of restoration increased, the SQ of the P. tabuliformis plantation forest progressively approached that of the long-term abandoned grassland, with only a 1.8% difference after 22 years of restoration. The SQI of the P. tabuliformis woodland in restored 6a was 83% higher than that of 1a, and following 6a of restoration, the SQI showed a decreasing trend with increasing restoration years. Nevertheless, the SQI increased by &gt;52% compared with the early stage of restoration (1a) and by 31% compared with the grassland before afforestation (PRG). (3) SEM revealed that the SQ of P. tabuliformis forest land was mainly driven by soil physical and herbaceous plant indicators, and soil fauna indicators and restoration years had a negative effect on the evolution of SQ in P. tabuliformis forests. The driving factors of P. tabuliformis forests of different restoration years were different, and with the increase in restoration years, the effects of soil fauna and herbaceous plant indicators on the SQ of P. tabuliformis plantation forests showed an overall upward trend.

Impacts of land use and management methods on soil quality dynamics in central highlands of Ethiopia.

Land degradation often results in poor soil quality in many parts of Ethiopia, including the study area. To address this issue and promote sustainable land management practices, various land use and management methods (LUMMs) have been implemented. However, little information is available regarding how these management practices influence overall soil quality dynamics of the study area. This study aimed at evaluating soil quality dynamics in the Urago micro-watershed, central highlands of Ethiopia, under major LUMMs: barren land (BL), grassland (GL), established farm boundary (EFB), restored degraded land (RDL), and stone-supported soil bund (SSB). Forty-five disturbed and fifteenundisturbed soil samples were collected from the ploughed soil layer (0-20cm) of each LUMM and analysed for selected physicochemical properties to be used as indicators of soil quality. Principal component analysis and multiple correlation were used to select the minimum data set (MDS) to evaluate the overall soil quality index (SQI). The MDS included SOC, clay content, exchangeable Mg2+, and available P, which could replace other indicators for assessing the overall soil quality dynamics of the study watershed. The result showed notable variations in particle-size fractions, soil organic carbon (SOC), total nitrogen (TN), available P (av. P), and exchangeable Na+, K+, and Mg2+ levels among the LUMMs. RDL had higher sand and silt contents than SSB, whereas SSB had higher clay content compared to RDL, GL, and BL. GL, RDL, and EFB showed significantly higher levels of SOC, TN, and av. P, respectively, compared to other LUMMs. The obtained SQI showed that GL had the highest score (0.847), followed by SSB (0.703), RDL (0.701), EFB (0.644), and BL (0.628). This underscores the significance of stone-supported soil bund and restored degraded land as an efficient management method to enhance soil quality and agro-ecosystem through conserving soil and encouraging sustainable farming practices.

A comprehensive evaluation of soil quality in the Three River Headwaters Region, China

Soil quality in the Three River Headwaters Region (TRHR) has a direct connection with the vegetation restoration and ecosystem health of the whole region, however, the evaluation of soil quality on a regional scale is still lacking. We analyzed the distribution pattern of the regional soil quality index (SQI), explored the dominant factors affecting SQI, and proposed measures to improve soil quality based on 638 soil samples collected at surface soil and subsurface soil. The results showed that in the TRHR, the SQI was higher in the southeast, and lower in the northwest. The average SQI were 0.52 for surface soil and 0.50 for subsurface soil, indicating better soil quality in the surface soil. Among different vegetation types within the TRHR, the SQI was ranked as follows: the alpine shrub (0.52–0.55) > the alpine meadow (0.51–0.52) > the alpine steppe (0.44–0.45). The study explored that NDVI was the dominant factor driving SQI, with geographical and climatic factors indirectly affected it through vegetation. This study proposes the corresponding strategies based on the distribution of SQI in different vegetation types and its main driving factor for the better development of soil quality in the TRHR, and it can provide practical guidance for remediating degraded soil, restoring degraded vegetation, and alleviating the impact of climate change.

Evaluation of soil quality of cultivated lands with classification and regression-based machine learning algorithms optimization under humid environmental condition

In soil science, machine learning algorithms are preferred for pedotransfer functions due to their rapid data acquisition and high prediction accuracy. The current study aims to evaluate the prediction of soil quality in agricultural lands dominated by the humid Black Sea climate using various algorithms. Both classification and regression-based algorithms (Random Forest-RF, Light Gradient Boosting-LGB, Extreme Gradient Boosting-XGBoost, k-nearest neighbors-kNN, Logistic Regression, multilayer perceptron-MLP, Linear Regression-LR and Bayesian Ridge- BR) were used in the method. The comparison of soil maps is also included. Furthermore, the present study evaluates the Grid Search optimization method with K-Fold Cross Validation (K = 5) for both classification and regression-based algorithms. The prediction of soil quality was performed using class-based and regression-based algorithms. As a result of the study, the RF and XGBoost algorithms achieved an approximate accuracy rate of 92 % in the class-based prediction. In regression-based predictions, the most successful algorithms were BR and LR, with an R2 Score of 0.84. The Grid Search optimization method was used to improve the R2 Score, resulting in an increase to 0.90 and 0.88 for BR and LR, respectively. The optimized hyperparameters showed improved performance in predicting the soil quality index. The present study found that Gaussian and Spherical models had the lowest prediction errors in spatial distribution maps. Tree-based algorithms were found to be suitable for class-based prediction of soil quality, while the linear regression method was appropriate for regression predictions. This study is characterized by a rainy climate resulting in acidic soils with high organic matter content. Planning of new studies in different climates and soil properties is recommended.

Changes in fungal abundance and biochemical properties of soil through a temporal restoration of forests

Changes due to the exploratory management of the soil and cultivated plant species can interfere with the cycling of nutrients vital for soil fertility. This biogeochemical cycling of soil is an interaction of physical, chemical, and biological processes that can be altered by land use change and management. Therefore, the objective of this study was to evaluate soil quality indicators in sand-extraction-degraded areas that had been reforested at different times and compare them to an unrestored area and native forest fragments. The five areas reforested with native Atlantic Forest species were 20, 17, 10, 7, and 5 years old. The fungal abundance, microbial respiration rate, enzyme activity, and C content were evaluated in soil samples collected at a depth of 10 cm. In addition, the total organic carbon, soluble carbon content, total carbohydrates, moisture, organic matter, and pH of these soils were studied. Our results verified a significant improvement in the fertile fraction of these soils due to the action of microorganisms in the different reforestation areas. The longer the reforestation period, the more the soil exhibited similar characteristics to native forests and approached the level of primary forests. The unrestored sand mining degraded soil area had the poorest fungal community and the least biochemical activity, which was less than the fungal abundance and activity of the most recent reforestation. These results suggest that the use of microbial and enzymatic activities as soil quality indicators is a viable approach to assess the impact suffered from past uncontrolled exploitation in areas that are undergoing ecological restoration processes of native forests.

Soil Quality Assessment and Influencing Factors of Different Land Use Types in Red Bed Desertification Regions: A Case Study of Nanxiong, China

Soil environmental issues in the red bed region are increasingly conspicuous, underscoring the critical importance of assessing soil quality for the region’s sustainable development and ecosystem security. This study examines six distinct land use types of soils—agricultural land (AL), woodland (WL), shrubland (SL), grassland (GL), bare rock land (BRL), and red bed erosion land (REL)—in the Nanxiong Basin of northern Guangdong Province. This area typifies red bed desertification in South China. Principal component analysis (PCA) was employed to establish a minimum data set (MDS) for calculating the soil quality index (SQI), evaluating soil quality, analyzing influencing factors, and providing suggestions for ecological restoration in desertification areas. The study findings indicate that a minimal data set comprising soil organic matter (SOM), pH, available phosphorus (AP), exchangeable calcium (Ca2+), and available copper (A-Cu) is most suitable for evaluating soil quality in the red bed desertification areas of the humid region in South China. Additionally, we emphasize that exchangeable salt ions and available trace elements should be pivotal considerations in assessing soil quality within desertification areas. Regarding comprehensive soil quality indicators across various land use types, the red bed erosion soils exhibited the lowest quality, followed by those in bare rock areas and forest land. Within the minimal data set, Ca2+ and pH contributed the most to overall soil quality, underscoring the significance of parent rock mineral composition in the red bed desertification areas. Moreover, the combined effects of SOM, A-Cu, and AP on soil quality indicate that anthropogenic land management and use, including fertilization methods and vegetation types, are crucial factors influencing soil quality. Our research holds significant implications for the scientific assessment, application, and enhancement of soil quality in desertification areas.

Soil quality assessment in the Araban plain across various land use types

BackgroundSoil is an important resource for improving the quality of human well-being and creating sustainable environmental awareness. Therefore, it is imperative to protect the soil health. This study determined quality of the soils in the Araban plain, Türkiye using three different methods, i.e., principal component analysis (PCA), analytic hierarchy process (AHP), and expert opinion (EO). The major aim was to determine the most appropriate method for determining soil quality and recommending soil protection practices for improving quality. MethodsThis study was conducted on an area of approximately 25,000 ha. A total of 230 soil samples (7 pasture areas, 56 orchards, and 167 arable crops) were analyzed to determine key soil quality indicators. A minimum dataset consisting of parameters that best represent the soils of the region was created. Subsequently, PCA was used to predict soil quality with the optimal accuracy using the least amount of data. The EO was incorporated to validate the PCA results. The AHP was used to assign weights to the parameters. Indicators at all sampling points were converted to unitless scorers. These scores were then formulated as soil quality index (SQI) using the weighted summation method. ResultsOrganic matter (OM) exerted the highest impact on soil quality. Significant variations in SQI values were observed among arable land, orchards land and pastureland (P < 0.01). Significant variations were recorded in SQI values of the assessment methods employed in this study. The lowest (0.552) and highest (0.829) SQI values were recorded for AHP and EO, respectively. Overall, streamlining indicators through PCA gave the most accurate result for SQI value. Subsequently, SQI determination should involve weighing with AHP, particularly towards EO. ConclusionThe AHP was found to be the most appropriate method for evaluating soil quality in Araban. This integrated approach ensures a robust evaluation of soil quality, facilitating more accurate and nuanced insights for informed land management decisions. Overall, 92.61 % of the region’s soil had poor and medium soil quality. Therefore, increasing OM content and aggregate stability are suggested to improve soil quality in the study region.

Application of soil quality evaluation indices and multivariate statistics to assess soil health: a case study

Application of soil quality evaluation indices and multivariate statistics to assess soil health: a case study

Soil quality enhancement by multi-treatment in the abandoned land of dry-hot river valley hydropower station construction area under karst desertification environment.

The medium-intensity karst desertification environment is typically characterized by more rocks and less soil. The abandoned land in the construction areas of the dry-hot river valley hydropower station has more infertile soil, severe land degradation, and very low land productivity. Therefore, it is urgent to improve the soil quality to curb the increasingly degrading land and reuse the construction site. Few studies have focused on the effect of soil restoration and comprehensive evaluation of soil quality with multi-treatment in abandoned land in the dry-hot valley hydropower station construction area. Here, 9 soil restoration measures and 1 control group were installed at the Guangzhao Hydropower Station construction in Guizhou Province, China, for physical and chemical property analysis. In total, 180 physical and 90 chemical soil samples were collected on three occasions in May, August, and December 2022. Soil fertility and quality were evaluated under various measures using membership functions and principal component analysis (PCA). This study showed that almost all measures could enhance soil water storage capacity (The average total soil porosity of 9 soil treatments was 57.56%, while that of the control group was 56.37%). With the increase in soil porosity, soil evaporation became stronger, and soil water content decreased. Nevertheless, no decrease in soil water content was observed in the presence of vegetation cover (soil water content: 16.46% of hairy vetch, 13.99% of clover, 13.77% of the control). They also proved that manure, synthetic fertilizer, and straw could promote total and available nutrients (Soil total nutrient content, or the total content of TN、TP、TK,was presented as: synthetic fertilizer (11.039g kg-2)>fowl manure (10.953g kg-2)>maize straw (10.560g kg-2)>control (9.580g kg-2);Total available nutrient content in soil, or the total content of AN,AP,A,was shown as:fowl manure (1287.670 mg kg-1)>synthetic fertilizer (925.889 mg kg-1)>sheep manure (825.979 mg kg-1)>control (445.486 mg kg-1). They could also promote soil fertility, among which the first two reached the higher comprehensive soil quality. Fertilizer was conducive to improve soil quality and fertility, yet long-term application could cause land degradation like soil non-point source pollution, compaction, and land productivity decline. Ultimately, combining fertilizer with biochar or manure is recommended to improve soil fertility. Biochar and green manure could play an apparent role in soil improvement only when there is abundant soil water. The above views provide theoretical support for curbing soil degradation, improving soil fertility and quality, enhancing land productivity, and promoting the virtuous cycle of the soil ecosystem.