Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivaria...Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQI<sub>add</sub> and WQI<sub>com</sub>) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TDS) and minimum data set (MDS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TDS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K<sup>+</sup> and Mg<sup>2+</sup>, bulk density and C/N ratio were retained in MDS, using principal component analysis (PCA). In the MDS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQI<sub>add</sub> and NQI, whereas the total was observed with WQI<sub>com</sub>. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQI<sub>add</sub> and NQI into the TDS and MDS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQI<sub>add</sub>. However, WQI<sub>add</sub> was chosen as the best SQI model, according to its high linear regression value (R<sup>2</sup> = 0.82) between TDS and MDS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.展开更多
Since there are some signs of land degradation and desertification showing how soil sustainability is threatened, it is crucial to create a soil quality index(SQI) model in the semi-arid ?orum Basin, situated between ...Since there are some signs of land degradation and desertification showing how soil sustainability is threatened, it is crucial to create a soil quality index(SQI) model in the semi-arid ?orum Basin, situated between the Black Sea and Anatolia Region, Central Turkey. The primary aims of the study are:(1) to determine SQI values of the micro-basin in terms of land degradation and desertification.Moreover, the best-worst method(BWM) was used to determine the weighting score for each parameter;(2) to produce the soils' spatial distribution by utilizing different geostatistical models and GIS(geographic information system) techniques;and(3) to validate the obtained SQI values with biomass reflectance values. Therefore, the relationship of RE-OSAVI(red-edge optimized soil-adjusted vegetation index) and NDVI(normalized difference vegetation index) generated from Sentinel-2A satellite images at different time series with soil quality was examined. Results showed that SQI values were high in the areas that had almost a flat and slight slope. Moreover, the areas with high clay content and thick soil depth did not have salinity problems, and were generally distributed in the middle parts of the basin. However, the areas with a high slope, poor vegetation, high sand content, and low water holding capacity had low SQI values.Furthermore, a statistically high positive correlation of RE-OSAVI and NDVI indices with soil quality was found, and NDVI had the highest correlative value for June(R~2=0.802) compared with RE-OSAVI.展开更多
Soil quality determination and estimation is an important issue not only for terrestrial ecosystems but also for sustainable management of soils.In this study,soil quality was determined by linear and nonlinear standa...Soil quality determination and estimation is an important issue not only for terrestrial ecosystems but also for sustainable management of soils.In this study,soil quality was determined by linear and nonlinear standard scoring function methods integrated with a neutrosophic fuzzy analytic hierarchy process in the micro catchment.In addition,soil quality values were estimated using a support vector machine(SVM)in machine learning algorithms.In order to generate spatial distribution maps of soil quality indice values,different interpolation methods were evaluated to detect the most suitable semivariogram model.While the soil quality index values obtained by the linear method were determined between 0.458-0.717,the soil quality index with the nonlinear method showed variability at the levels of 0.433-0.651.There was no statistical difference between the two methods,and they were determined to be similar.In the estimation of soil quality with SVM,the normalized root means square error(NRMSE)values obtained in the linear and nonlinear method estimation were determined as 0.057 and 0.047,respectively.The spherical model of simple kriging was determined as the interpolation method with the lowest RMSE value in the actual and predicted values of the linear method while,in the nonlinear method,the lowest error in the distribution maps was determined with exponential of the simple kriging.展开更多
Soil is the major source of infinite lives on Earth and the quality of soil plays significant role on Agriculture practices all around.Hence,the evaluation of soil quality is very important for determining the amount ...Soil is the major source of infinite lives on Earth and the quality of soil plays significant role on Agriculture practices all around.Hence,the evaluation of soil quality is very important for determining the amount of nutrients that the soil require for proper yield.In present decade,the application of deep learning models in many fields of research has created greater impact.The increasing soil data availability of soil data there is a greater demand for the remotely avail open source model,leads to the incorporation of deep learning method to predict the soil quality.With that concern,this paper proposes a novel model called Improved Soil Quality Prediction Model using Deep Learning(ISQP-DL).The work considers the chemical,physical and biological factors of soil in particular area to estimate the soil quality.Firstly,pH rating of soil samples has been collected from the soil testing laboratory from which the acidic range has been categorized through soil test and the same data has been taken as input to the Deep Neural Network Regression(DNNR)model.Secondly,soil nutrient data has been given as second input to the DNNR model.By utilizing this data set,the DNNR method is used to evaluate the fertility rate by which the soil quality has been estimated.For training and testing,the model uses Deep Neural Network Regression(DNNR),by utilizing the dataset.The results show that the proposed model is effective for SQP(Soil Quality Prediction Model)with efficient good fitting and generality is enhanced with input features with higher rate of classification accuracy.The results show that the proposed model achieves 96.7%of accuracy rate compared with existing models.展开更多
Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil...Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil quality SQ in the main agroecosystems (AES) of the eastern flank of Mount Bambouto (West, Cameroon). Using multiple statistics tests and principal component analysis (PCA), SOCS and Soil Quality Index (SQI) were computed for each AES. SOCS and SQI were computed based on soil chemical properties and analysis of variance. Topsoil samples (0 - 30 cm) were collected in a different AES and analyzed in the laboratory. The four AES identified and selected are cultivated land (CL), forest areas (FA), mixed areas (MA), and bush areas (BA). Further, multiple comparison tests were used to compare soils from different AES. PCA was used to select the most appropriate indicators that control SOCS and SQ. Several soil properties showed high to very high coefficient of variation within the AES. Organic matter (OM) was significantly high in FA. SOCS and SQ differ significantly (p = 0.000) between the AES. The study further indicates that the main variables controlling SQ within the eastern flank of Mount Bambouto are OM, pHw, N, C/N, and CEC. While the main soil parameters controlling SOCS are OM, OC, BD, C/N, S, and pHKCl.展开更多
To examine changes in surface soil quality over time in Populus×xiaohei shelterbelts,we collected soil samples from five shelterbelts of different ages and also from former cropland left fallow for 25 years.Twent...To examine changes in surface soil quality over time in Populus×xiaohei shelterbelts,we collected soil samples from five shelterbelts of different ages and also from former cropland left fallow for 25 years.Twenty-one surface soil(0–20 cm)properties were measured,and variation in soil quality was assessed using one-way ANOVAs and multiple comparison tests.Based on this analysis,16 soil indexes were used in a model evaluating soil quality,with each index given weight as determined by the correlation coefficient.Compared with the control,the postmature forest had greater soil moisture content but lower bulk density(P<0.05).The mature forest also had higher soil pH,total organic carbon,alkali-hydrolyzed nitrogen,available phosphorus,and biomass nitrogen content,but reduced nitrate-nitrogen and total phosphorus content than the control(P<0.05).Total porosity was highly positively correlated with aeration,nitrate-nitrogen,alkali-hydrolyzed nitrogen,available phosphorus,microbial biomass carbon and microbial biomass nitrogen.Soil total organic carbon,ammonium nitrogen,nitrate-nitrogen,alkali-hydrolyzed nitrogen,total nitrogen,available phosphorus,microbial biomass carbon and microbial biomass nitrogen were all strongly correlated.In the soil quality evaluation model,total organic carbon was assigned the highest weight and total potassium content the lowest.The soil quality index was lowest in the near-mature forest and greatest in the postmature forest.Generally,soil quality in P opulus×xiaohei shelterbelts varied with age and was higher in the 10–20 cm versus 0–10 cm soil layer.After a single forest generation,surface soil quality was significantly improved.展开更多
Most agricultural soils in sub-Saharan Africa are degraded,compromising the grain yield of rice and farmers return on investment.A 3-year field study was undertaken to explore the effect of the application of compost ...Most agricultural soils in sub-Saharan Africa are degraded,compromising the grain yield of rice and farmers return on investment.A 3-year field study was undertaken to explore the effect of the application of compost or inorganic NPK fertilizer applied alone or in combination with biochar on soil quality,grain yield of rice and net income.The five treatments were laid out using a randomized complete block design with four replications.The treatments were applied to supply approximately 75 kg N ha–1.The best fertilizer input was compost+biochar which resulted in the greatest improvement in soil physico-chemical properties by reducing bulk density and increasing porosity and moisture retention,organic matter content,percent nitrogen,available phosphorus and cation exchange capacity.Apart from treatment with inorganic fertilizer alone,treated soils showed a decrease in pH.Bacterial and fungal counts and basal respiration decreased in soils in the following order:compost+biochar>compost only>inorganic NPK fertilizer+biochar>inorganic NPK fertilizer>control.The increase in pooled grain yield and net income in response to treatment followed the order:compost+biochar>NPK+biochar>NPK>compost>control.The findings suggest that the use of compost or NPK alone might improve soil quality and increase grain yield and net income,but it is greatly recommended to co-apply these fertilisers with biochar.展开更多
There are numerous valley farmlands on the Chinese Loess Plateau(CLP),where suffers from low soil quality and high risk of soil salinization due to the shallow groundwater table and poor drainage system.Currently,rese...There are numerous valley farmlands on the Chinese Loess Plateau(CLP),where suffers from low soil quality and high risk of soil salinization due to the shallow groundwater table and poor drainage system.Currently,research on the evolution processes and mechanisms of soil quality and salinization in these dammed-valley farmlands on the CLP is still inadequately understood.In this study,three kinds of dammed-valley farmlands in the hilly-gully areas of the northern CLP were selected,and the status of soil quality and the impact factors of soil salinization were examined.The dammed-valley farmlands include the new farmland created by the project of Gully Land Consolidation,the 60-a farmland created by sedimentation from check dam,and the 400-a farmland created by sedimentation from an ancient landslide-dammed lake.Results showed that(1)the newly created farmland had the lowest soil quality in terms of soil bulk density,porosity,soil organic carbon and total nitrogen among the three kinds of dammed-valley farmlands;(2)soil salinization occurred in the middle and upper reaches of the new and 60-a valley farmlands,whereas no soil salinization was found in the 400-a valley farmland;and(3)soil salinization and low soil nutrient were determined to be the two important factors that impacted the soil quality of the valley farmlands in the hilly-gully mountain areas of the CLP.We conclude that the dammed-valley farmlands on the CLP have a high risk of soil salinization due to the shallow groundwater table,alkalinity of the loessial soil and local landform feature,thus resulting in the low soil quality of the valley farmlands.Therefore,strengthening drainage and decreasing groundwater table are extremely important to improve the soil quality of the valley farmlands and guarantee the sustainable development of the valley agriculture on the CLP.展开更多
This study investigated the effects of six crop rotation combinations on the soil quality of old apple orchard and seedling growth of Malus hupehensis Rehd.(apple rootstock) under pot conditions. The inhibitory effect...This study investigated the effects of six crop rotation combinations on the soil quality of old apple orchard and seedling growth of Malus hupehensis Rehd.(apple rootstock) under pot conditions. The inhibitory effects of crops such as Allium fistulosum, Brassica juncea, and Triticum aestivum on four species of Fusarium were observed and compared in six treatments. These were continuous cropping(CK), fumigation with the methyl bromide(FM), rotating A. fistulosum only(R1), rotating A. fistulosum and T. aestivum(R2), rotating A. fistulosum, B. juncea, and T. aestivum(R3), and fallow(FC) in a year. The results showed that the biomass of Malus hupehensis Rehd. seedlings increased significantly. The root length increased and the root architecture was optimized. The respiration rate of the root system was increased by about 1 time after rotation. The treatments of R1, R2, R3, and FC increased bacterial count by 232.17%, 96.04%, 316.21%, and 60.02%, respectively. However, the fungi were reduced in varying degrees and bacteria/fungi ratio was increased by 5–10 times. The enzyme activities, p H, and organic matter were increased, but soil bulk density was decreased. Phenolic acids such as phloridzin was decreased significantly. The copy number of four Fusarium species declined by 85.59%, 74.94%, 69.68%, and 54.41% after rotating three different crops(R3 treatment). The root volatiles of three plants inhibited mycelial growth and spore germination of four Fusarium species.展开更多
[Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide...[Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide a theoretical basis for maintaining the sustainable development of soil in Hetao Irrigation District. [Methods] The methods of experiment, questionnaire, on-the-spot investigation and literature review were used. [Results] This study proposed the empirical framework of washing salinity by irrigation to maintain soil quality in Hetao Irrigation District. Seven factors of the framework, including flood irrigation, land leveling, plastic film mulching, fertilization, soil organic matter, pH and salinity, and their relationships were determined. The characteristics of these factors in Hetao Irrigation District were investigated(flooding irrigation with a large amount of irrigation water, high amount of fertilizer application, low organic matter, high pH, large variation of salinity, etc.). The mechanisms and effects of various factors affecting soil quality in Hetao Irrigation District were analyzed(the mean soil organic matter(SOM) and pH were kept in the range of 10.9-13.9 g/kg and 8.0-8.15 in recent 35 years, respectively, and increased slightly, etc.). [Conclusions] The empirical framework can be used as a theoretical norm for evaluating soil quality under the condition of washing salinity by irrigation. Under the condition of washing salinity by irrigation, the agricultural soil quality in Hetao Irrigation District showed a stable trend over time. Using this framework, we can find soil problems, and adjust some unbalanced factors to maintain the stability of soil quality in Hetao Irrigation District, and can also provide a reference for other areas.展开更多
For hydrocarbon polluted soils that underwent bioremediation it is important to assess its condition after a period of time, but it is more useful when there is an opportunity of comparison against an unpolluted soil ...For hydrocarbon polluted soils that underwent bioremediation it is important to assess its condition after a period of time, but it is more useful when there is an opportunity of comparison against an unpolluted soil and an untreated polluted one. This paper provides a comparison of three adjacent parcels, being the first clean, the second polluted and bioremediated, the third polluted and left to natural attenuation. Study was conducted determining pH, electrical conductivity, carbonates, soil organic matter, chemical oxygen demand, eight anions, and twelve metals. Data were compared against those references for agricultural soils found in the Mexican NOM-021. A Pearson correlation was applied to find coincidences between the three parcels, obtained results allowed to say that bioremediated parcel allowed for most uniform pH, negligible salinity risk, and medium content of soil organic matter, but treatment has enabled heavy metal accumulation since its values are higher in respect to the other parcels. Natural attenuated parcel has some spots with lower pH, a moderately saline risk, a high content of soil organic matter, and lower content of heavy metals. The clean or unaffected parcel exhibit the higher pH values, a slightly saline condition, soil organic matter ranges from high to very high content, heavy metals content is medium, but no reaching dangerous levels. An important assessment is that bioremediation has enhanced the bioavailability of soil organic matter but it is not similar to the values in the unpolluted parcel.展开更多
The study examined the impacts of urbanization-related activities on soil quality in Port Harcourt Metropolis-Rivers state,Nigeria.Experimental and survey research designs were implored in the study utilizing GIS and ...The study examined the impacts of urbanization-related activities on soil quality in Port Harcourt Metropolis-Rivers state,Nigeria.Experimental and survey research designs were implored in the study utilizing GIS and spatial analysis approaches.Both primary and secondary sources of data were used.The primary data were generated through laboratory analysis of soil samples from 15 randomly selected sites within the metropolis;and 800 valid copies of socio-economic questionnaire administered to 800 respondents.Also,public hospitals were visited to ascertain the commonest soil borne diseases in the area.Four research questions,four specific objectives and two hypotheses guided the study.The hypotheses were tested with one sample t-test and one sample chi square using SPSS.Standard scientific and laboratory procedures were followed in the collection and analysis of soil samples.Findings of the study include:urbanization-related activities(e.g.waste dumpsites,mechanic workshops,abattoirs,etc.)cause significant changes on soil quality in the area;and this result to the emergence of soil borne diseases(e.g.Vascular witts,Ascaris lumbricoids,Trichuris trichiura,Strongloids stereoralis)which affects residents’wellbeing.However,there is significant difference in the perceived socio-economic effects of the diseases across the area.Specifically,laboratory results for soil analysis show that(mean values):pH 7.22,temperature 25.62℃,PO_(4)0.342 mg/kg,Pb 120.62 mg/kg,K 66.81 mg/kg,NO_(3)mg/kg.The study recommended for enforcement of physical planning and development control laws;regular evaluation of the quality of the soil,and restriction on the location of mechanic workshops and waste dumpsites around the metropolis.展开更多
[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient el...[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient element content and metabolites of C.oleifera.C.oleifera was inoculated with the suspension of Fusarium sp.in pot experiments and ammonium-N,available phosphorus,available potassi-um,organic matter,enzymes and pH of rhizosphere soil,MDA content,activity of SOD,POD of C.oleifera leaves were analyzed.[Results]Fusarium sp.stress significantly inhibited soil enzyme activities and significantly reduced available phosphorus content,especially for phospha-tase and sucrase.Antioxidant enzyme activities in C.oleifera tissues showed that Fusarium sp.stress significantly increased MDA and SOD enzyme activities and decreased POD enzyme activity.Especially,SOD enzyme activity was elevated by 53.86%compared with the CK group.In addition,analysis of the content of major metabolites in C.oleifera leaves showed that Fusarium sp.stress significantly reduced the content of total flavonoids,quercetin,isoquercitrin and isoquercitrin in C.oleifera leaves by 7.80%,50.00%and 75.90%,respectively.[Conclusions]Our results are an important step which showed strong resistance of C.oleifera and can give a novel insight for researches on the effects in the rhizosphere soil enzyme,soil nutrient elements and metabolites of C.oleifera under the Fusarium sp.too.展开更多
Grasslands provide a number of ecosystem services for human society.Degradation of grasslands results in the loss of biodiversity and leads to the deterioration of ecosystem functions.In order to accurately assess the...Grasslands provide a number of ecosystem services for human society.Degradation of grasslands results in the loss of biodiversity and leads to the deterioration of ecosystem functions.In order to accurately assess the influence of grassland degradation on belowground ecosystems,we conducted experiments on a temperate steppe with different levels of degradation and investigated the influence of degradation on soil quality and soil biotic communities.Our results showed that grassland degradation significantly decreased soil quality,with lower values of soil quality index(SQI)observed in the degraded grassland than the meadow steppe and the grassland from the forest-steppe ecotone.Changes in the SQI along the grassland degradation gradient were positively correlated with soil carbon stock and the aboveground biomass,and negatively correlated with the root shoot ratio.Nematode trophic diversity and the ratio of fungal to bacterial PLFA were lower in the degraded grassland than the grassland from the forest-steppe ecotone.The dissimilarities in soil microbial and nematode community composition increased with the changes in soil quality index.Our results indicate that soil quality index based on the minimum data sets could effectively assess the influence of grassland degradation on soil biodiversity and ecosystem function.In order to effectively restore degraded grasslands,the key contributors to the soil quality,such as soil carbon,should be taken on priority basis for revitalizing the soil biodiversity and ecosystem function.展开更多
Understanding the influence of collapsing gully management restoration on soil quality and function is essential to the protection of the regional ecological environment in the collapsing gully erosion area.The primar...Understanding the influence of collapsing gully management restoration on soil quality and function is essential to the protection of the regional ecological environment in the collapsing gully erosion area.The primary objective of this study was to construct soil quality index(SQI)to assess the influence of different vegetation restoration types on soil quality in collapsing gully restoration.The influence of five vegetation restoration types on soil properties was investigated by using a path analysis,a comprehensive soil quality index(SQI),and a general linear model(GLM).Vegetation restoration was shown to significantly increase the saturated hydraulic conductivity(Ks),mainly due to the effect of the physical parameters of bulk density,soil cohesion,and soil water content.Meanwhile,pH,Ks,soil organic matter(OM),and sand content were revealed as reasonable indicators to evaluate the influence of vegetation restoration on soil quality.Moreover,vegetation restoration was found to significantly improve the soil quality,with the highest SQI value for natural restoration mixed forest(NF),followed by replanted arboreal forest(RA)and replanted scrubland(RS),which were all significantly higher than the SQI value of the erosion area(EA)in the collapsing gully.Additionally,vegetation type explained the most substantial proportion of total variability(46.41%),and restoration time showed a positive correlation with SQI.The results of this study can provide a reference for the restoration and protection of the regional ecological environment in the collapsing gully area.展开更多
Background:Shifting cultivation is a major agriculture practice in the Nagaland state of India.This study examines the effect of shifting cultivation and the length of the fallow period on soil quality index(SQI).Four...Background:Shifting cultivation is a major agriculture practice in the Nagaland state of India.This study examines the effect of shifting cultivation and the length of the fallow period on soil quality index(SQI).Four sites were selected for the study,viz.,a shifting cultivation site(SCS),a 3-year-old fallow land(FL-3),a 7-year-old fallow land(FL-7),and a 12-year-old fallow land(FL-12).Soil parameters were recorded seasonally and SQI was calculated from the minimum data set.Results:With the increase in the fallow period,the values of conductivity,soil organic carbon,available nitrogen,available phosphorus,exchangeable potassium,moisture,clay,and cation exchange capacity of soil increased.Meanwhile,soil pH and bulk density decreased with fallow duration.The additive SQI_(a)values were in the order SCS<FL-3<FL-12<FL-7;meanwhile,the weighted SQI_(w)values were in the order SCS<FL-3<FL-7<FL-12.It is also observed that the SQI value decreases with the increase in soil depth under both the weighted and additive indexes.SCS with the lowest SQI value reflects the reduced soil organic carbon(SOC)and macronutrients.Increased SOC levels in site FL-12(2.88–3.94%)may be one reason for its higher SQI value.Conclusions:Our study highlights that unsustainable practices of shifting cultivation and reduction in the fallow period negatively affect soil quality.Furthermore,the study also recommends the use of the weighted method of SQI as it agrees with the reports of land use causing alteration in the soil quality.Our findings may be utilized to quickly access and disseminate information to the stakeholders and aid in constructing local soil quality index maps of the region.There is an urgent need for a rapid,cost and resource-efficient soil quality assessment and SQI may be one tool that achieves this goal.展开更多
Reuse of industrial wastewater(effluent)for irrigation purpose is a common practice.However,lack of adequate treatment of the effluent can cause soil deterioration,vegetation destruction and contamination of the aquat...Reuse of industrial wastewater(effluent)for irrigation purpose is a common practice.However,lack of adequate treatment of the effluent can cause soil deterioration,vegetation destruction and contamination of the aquatic environment.These adverse effects necessitated the study of wastewater irrigation in Emene Industrial Layout,Enugu State,Nigeria.Wastewater and soil samples were collected,analyzed and subjected to Analysis of Variance(ANOVA)for Completely Randomized Design(CRD)at 5% probability level using GENSTAT software.The results obtained from the study were compared with FAO soil and water standards.The wastewater analysis suggested that contamination at the untreated stage was very high and results at the treatment level were within the FAO reuse range.The study also found wide variation in chemical status of industrial wastewater treated soil.Almost all the values for the wastewater treated soil were not within the FAO irrigated soil chemical properties standards.This suggests high re-contamination along the open channel(from non-point sources)before reuse.This calls for proper monitoring and treatment of the industrial effluent prior to irrigation application.展开更多
Vegetable greenhouses form a significant land utilisation pattern in China.A case study of the greenhouse soil quality changes and potential risk to humans under a specific long-term environment,which includes high fe...Vegetable greenhouses form a significant land utilisation pattern in China.A case study of the greenhouse soil quality changes and potential risk to humans under a specific long-term environment,which includes high fertilization rates,high temperatures and humidity levels and out-of-season cultivation,is presented in this study.Soil profiles of 72 representative solar greenhouses with various planting years were sampled in Shouguang City,which is the birthplace of winter greenhouse in China.The temporal distribution of soil quality changes were quantitatively evaluated through the application of a correlation analysis and soil quality assessment.The soil was highly enriched with phosphorus and potassium and had low organic matter content.The organic matter,nitrogen,phosphorus and potassium contents increased with the years planted,reached their peak values after 5-10 a,and declined as the soil layer’s depth increased.The infiltration rate of nitrate was relatively high,which poses risks to underground water safety.A comprehensive soil quality assessment revealed that in vegetable greenhouses planted for different periods,the soil quality improved at first and then sharply declined after 10 a.Studying greenhouse soil quality changes will aid in implementing nutrient management strategies to improve the soil quality and sustainable development programs for the vegetable industry.展开更多
There have been many studies on soil quality and crop yield using different biochar application amounts,but few studies have focused on the combination of different methods and amounts of biochar application in modera...There have been many studies on soil quality and crop yield using different biochar application amounts,but few studies have focused on the combination of different methods and amounts of biochar application in moderately degraded Mollisols.In this study,the methods of mixing biochar evenly with the soil of the plough layer(0-20 cm depth)[homogeneous biochar application(HO)]and burying biochar above the soil plow pan(under 20 cm depth)(heterogeneous biochar application(HE))were used to reveal how biochar application methods influenced soil quality,crop yield and agronomic characteristics in moderately degraded Mollisols(soil organic matter(SOM),30.33 g kg^(−1)).The biochar application amounts were 0(control),10(level 1),20(level 2),and 40(level 3)t ha^(−1)in both the HO and HE treatments.The results showed that,compared with control,HO3 significantly increased maize yield in the first year,and HO2,HO3,HE2 and HE3 continuously increased maize yield in the next three years but not significantly.HO1 and HE1 had the lowest maize yield.HO2 tended to delay maize leaf senescence.There was a posi-tive linear relationship between soil quality index(SQI)and biochar application amount in HO.Compared with other treatments,the pH,EC,SOM,available phosphorus,sucrase and catalase activities were highest in HO3.However,the effects of HE on soil quality and crop productivity were limited at first but gradually increased with time.Overall,HO3 was beneficial for improving the soil quality and crop productivity in Mollisols for short-term cultivation(3-year),while HE showed an effect over time.展开更多
Increasing the quantity and improving the quality of cropland can alleviate the human-land contradiction and promote the sustainable development of agriculture especially in mountainous areas.With the support of the c...Increasing the quantity and improving the quality of cropland can alleviate the human-land contradiction and promote the sustainable development of agriculture especially in mountainous areas.With the support of the central government’s policies,Yan’an,Northern Shaanxi,China implemented a major land consolidation engineering project in the loess hilly-gully region from 2013 to 2018,achieving 33,333.3 ha of new cropland.However,the poor quality of some newly-constructed cropland at the initial stage hindered its efficient utilization.In order to overcome this problem,red clay and Malan loess were compounded in different volume ratios to explore the method to improve the cropland quality.The Root Zone Water Quality Model was used to simulate the effects of different soil treatments on soil water,nitrogen and maize growth.Experimental data were collected from 2018 to 2019 to calibrate and validate the model.The root mean square error(RMSE)of soil water content,nitrate nitrogen concentration,above-ground biomass,leaf area index were in the range of 11.72-14.06 mm,4.06-11.73 mg kg^(-1),835.21-1151.28 kg ha^(-1)and 0.24-0.47,respectively,while the agreement index(d)between measured and simulated values ranged from 0.70 to 0.96.It was showed that,compared with land constructed with Malan loess only(T1),the soil structure and hydraulic characteristics of land with a volume ratio of red clay and Malan loess of 2:1(T3)was better.Simulation indicated that,compared with T1,the soil water content and available water content of T3 increased by 14.4%and 19.0%,respectively,while N leaching decreased by 16.9%.The aboveground biomass and maize yield of T3 were 7.9%and 6.7%higher than that of T1,respectively.Furthermore,the water productivity and nitrogen use efficiency of T3 increased by 21.0%and 16.6%compared with that of T1.These results indicated that compounding red clay and Malan loess in an appropriate ratio was an effective method to improve soil quality.This study provides a technical idea and specific technical parameters for the construction or improvement of cropland in loess hilly-gully region,which may also provide reference for similar projects in other places.展开更多
文摘Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQI<sub>add</sub> and WQI<sub>com</sub>) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TDS) and minimum data set (MDS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TDS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K<sup>+</sup> and Mg<sup>2+</sup>, bulk density and C/N ratio were retained in MDS, using principal component analysis (PCA). In the MDS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQI<sub>add</sub> and NQI, whereas the total was observed with WQI<sub>com</sub>. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQI<sub>add</sub> and NQI into the TDS and MDS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQI<sub>add</sub>. However, WQI<sub>add</sub> was chosen as the best SQI model, according to its high linear regression value (R<sup>2</sup> = 0.82) between TDS and MDS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.
文摘Since there are some signs of land degradation and desertification showing how soil sustainability is threatened, it is crucial to create a soil quality index(SQI) model in the semi-arid ?orum Basin, situated between the Black Sea and Anatolia Region, Central Turkey. The primary aims of the study are:(1) to determine SQI values of the micro-basin in terms of land degradation and desertification.Moreover, the best-worst method(BWM) was used to determine the weighting score for each parameter;(2) to produce the soils' spatial distribution by utilizing different geostatistical models and GIS(geographic information system) techniques;and(3) to validate the obtained SQI values with biomass reflectance values. Therefore, the relationship of RE-OSAVI(red-edge optimized soil-adjusted vegetation index) and NDVI(normalized difference vegetation index) generated from Sentinel-2A satellite images at different time series with soil quality was examined. Results showed that SQI values were high in the areas that had almost a flat and slight slope. Moreover, the areas with high clay content and thick soil depth did not have salinity problems, and were generally distributed in the middle parts of the basin. However, the areas with a high slope, poor vegetation, high sand content, and low water holding capacity had low SQI values.Furthermore, a statistically high positive correlation of RE-OSAVI and NDVI indices with soil quality was found, and NDVI had the highest correlative value for June(R~2=0.802) compared with RE-OSAVI.
文摘Soil quality determination and estimation is an important issue not only for terrestrial ecosystems but also for sustainable management of soils.In this study,soil quality was determined by linear and nonlinear standard scoring function methods integrated with a neutrosophic fuzzy analytic hierarchy process in the micro catchment.In addition,soil quality values were estimated using a support vector machine(SVM)in machine learning algorithms.In order to generate spatial distribution maps of soil quality indice values,different interpolation methods were evaluated to detect the most suitable semivariogram model.While the soil quality index values obtained by the linear method were determined between 0.458-0.717,the soil quality index with the nonlinear method showed variability at the levels of 0.433-0.651.There was no statistical difference between the two methods,and they were determined to be similar.In the estimation of soil quality with SVM,the normalized root means square error(NRMSE)values obtained in the linear and nonlinear method estimation were determined as 0.057 and 0.047,respectively.The spherical model of simple kriging was determined as the interpolation method with the lowest RMSE value in the actual and predicted values of the linear method while,in the nonlinear method,the lowest error in the distribution maps was determined with exponential of the simple kriging.
文摘Soil is the major source of infinite lives on Earth and the quality of soil plays significant role on Agriculture practices all around.Hence,the evaluation of soil quality is very important for determining the amount of nutrients that the soil require for proper yield.In present decade,the application of deep learning models in many fields of research has created greater impact.The increasing soil data availability of soil data there is a greater demand for the remotely avail open source model,leads to the incorporation of deep learning method to predict the soil quality.With that concern,this paper proposes a novel model called Improved Soil Quality Prediction Model using Deep Learning(ISQP-DL).The work considers the chemical,physical and biological factors of soil in particular area to estimate the soil quality.Firstly,pH rating of soil samples has been collected from the soil testing laboratory from which the acidic range has been categorized through soil test and the same data has been taken as input to the Deep Neural Network Regression(DNNR)model.Secondly,soil nutrient data has been given as second input to the DNNR model.By utilizing this data set,the DNNR method is used to evaluate the fertility rate by which the soil quality has been estimated.For training and testing,the model uses Deep Neural Network Regression(DNNR),by utilizing the dataset.The results show that the proposed model is effective for SQP(Soil Quality Prediction Model)with efficient good fitting and generality is enhanced with input features with higher rate of classification accuracy.The results show that the proposed model achieves 96.7%of accuracy rate compared with existing models.
文摘Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil quality SQ in the main agroecosystems (AES) of the eastern flank of Mount Bambouto (West, Cameroon). Using multiple statistics tests and principal component analysis (PCA), SOCS and Soil Quality Index (SQI) were computed for each AES. SOCS and SQI were computed based on soil chemical properties and analysis of variance. Topsoil samples (0 - 30 cm) were collected in a different AES and analyzed in the laboratory. The four AES identified and selected are cultivated land (CL), forest areas (FA), mixed areas (MA), and bush areas (BA). Further, multiple comparison tests were used to compare soils from different AES. PCA was used to select the most appropriate indicators that control SOCS and SQ. Several soil properties showed high to very high coefficient of variation within the AES. Organic matter (OM) was significantly high in FA. SOCS and SQ differ significantly (p = 0.000) between the AES. The study further indicates that the main variables controlling SQ within the eastern flank of Mount Bambouto are OM, pHw, N, C/N, and CEC. While the main soil parameters controlling SOCS are OM, OC, BD, C/N, S, and pHKCl.
基金supported by Forestry Industry Research Special Funds for Public Welfare Projects(2014040202-01)。
文摘To examine changes in surface soil quality over time in Populus×xiaohei shelterbelts,we collected soil samples from five shelterbelts of different ages and also from former cropland left fallow for 25 years.Twenty-one surface soil(0–20 cm)properties were measured,and variation in soil quality was assessed using one-way ANOVAs and multiple comparison tests.Based on this analysis,16 soil indexes were used in a model evaluating soil quality,with each index given weight as determined by the correlation coefficient.Compared with the control,the postmature forest had greater soil moisture content but lower bulk density(P<0.05).The mature forest also had higher soil pH,total organic carbon,alkali-hydrolyzed nitrogen,available phosphorus,and biomass nitrogen content,but reduced nitrate-nitrogen and total phosphorus content than the control(P<0.05).Total porosity was highly positively correlated with aeration,nitrate-nitrogen,alkali-hydrolyzed nitrogen,available phosphorus,microbial biomass carbon and microbial biomass nitrogen.Soil total organic carbon,ammonium nitrogen,nitrate-nitrogen,alkali-hydrolyzed nitrogen,total nitrogen,available phosphorus,microbial biomass carbon and microbial biomass nitrogen were all strongly correlated.In the soil quality evaluation model,total organic carbon was assigned the highest weight and total potassium content the lowest.The soil quality index was lowest in the near-mature forest and greatest in the postmature forest.Generally,soil quality in P opulus×xiaohei shelterbelts varied with age and was higher in the 10–20 cm versus 0–10 cm soil layer.After a single forest generation,surface soil quality was significantly improved.
文摘Most agricultural soils in sub-Saharan Africa are degraded,compromising the grain yield of rice and farmers return on investment.A 3-year field study was undertaken to explore the effect of the application of compost or inorganic NPK fertilizer applied alone or in combination with biochar on soil quality,grain yield of rice and net income.The five treatments were laid out using a randomized complete block design with four replications.The treatments were applied to supply approximately 75 kg N ha–1.The best fertilizer input was compost+biochar which resulted in the greatest improvement in soil physico-chemical properties by reducing bulk density and increasing porosity and moisture retention,organic matter content,percent nitrogen,available phosphorus and cation exchange capacity.Apart from treatment with inorganic fertilizer alone,treated soils showed a decrease in pH.Bacterial and fungal counts and basal respiration decreased in soils in the following order:compost+biochar>compost only>inorganic NPK fertilizer+biochar>inorganic NPK fertilizer>control.The increase in pooled grain yield and net income in response to treatment followed the order:compost+biochar>NPK+biochar>NPK>compost>control.The findings suggest that the use of compost or NPK alone might improve soil quality and increase grain yield and net income,but it is greatly recommended to co-apply these fertilisers with biochar.
基金This study was funded by the National Natural Science Foundation of China(41790444)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB40000000)the National Key Research and Development Program of China(2018YFC1504701).
文摘There are numerous valley farmlands on the Chinese Loess Plateau(CLP),where suffers from low soil quality and high risk of soil salinization due to the shallow groundwater table and poor drainage system.Currently,research on the evolution processes and mechanisms of soil quality and salinization in these dammed-valley farmlands on the CLP is still inadequately understood.In this study,three kinds of dammed-valley farmlands in the hilly-gully areas of the northern CLP were selected,and the status of soil quality and the impact factors of soil salinization were examined.The dammed-valley farmlands include the new farmland created by the project of Gully Land Consolidation,the 60-a farmland created by sedimentation from check dam,and the 400-a farmland created by sedimentation from an ancient landslide-dammed lake.Results showed that(1)the newly created farmland had the lowest soil quality in terms of soil bulk density,porosity,soil organic carbon and total nitrogen among the three kinds of dammed-valley farmlands;(2)soil salinization occurred in the middle and upper reaches of the new and 60-a valley farmlands,whereas no soil salinization was found in the 400-a valley farmland;and(3)soil salinization and low soil nutrient were determined to be the two important factors that impacted the soil quality of the valley farmlands in the hilly-gully mountain areas of the CLP.We conclude that the dammed-valley farmlands on the CLP have a high risk of soil salinization due to the shallow groundwater table,alkalinity of the loessial soil and local landform feature,thus resulting in the low soil quality of the valley farmlands.Therefore,strengthening drainage and decreasing groundwater table are extremely important to improve the soil quality of the valley farmlands and guarantee the sustainable development of the valley agriculture on the CLP.
基金supported by the National Natural Science Foundation of China (Grant No. 31672104)China Agriculture Research System of MOF and MARA (Grant No. CARS-27)+4 种基金Shandong Agricultural Major Applied Technology Innovation Project (Grant No. SD2019ZZ008)Taishan Scholar Funded Project(Grant No. 20190923)Qingchuang Science and Technology Support Project of Shandong Colleges and Universities (Grant No.2019KJF020)Natural Science Foundation of Shandong Province(Grant No. ZR2020MC131)the National Key Research and Development Program of China (Grant No. 2020YFD1000201)。
文摘This study investigated the effects of six crop rotation combinations on the soil quality of old apple orchard and seedling growth of Malus hupehensis Rehd.(apple rootstock) under pot conditions. The inhibitory effects of crops such as Allium fistulosum, Brassica juncea, and Triticum aestivum on four species of Fusarium were observed and compared in six treatments. These were continuous cropping(CK), fumigation with the methyl bromide(FM), rotating A. fistulosum only(R1), rotating A. fistulosum and T. aestivum(R2), rotating A. fistulosum, B. juncea, and T. aestivum(R3), and fallow(FC) in a year. The results showed that the biomass of Malus hupehensis Rehd. seedlings increased significantly. The root length increased and the root architecture was optimized. The respiration rate of the root system was increased by about 1 time after rotation. The treatments of R1, R2, R3, and FC increased bacterial count by 232.17%, 96.04%, 316.21%, and 60.02%, respectively. However, the fungi were reduced in varying degrees and bacteria/fungi ratio was increased by 5–10 times. The enzyme activities, p H, and organic matter were increased, but soil bulk density was decreased. Phenolic acids such as phloridzin was decreased significantly. The copy number of four Fusarium species declined by 85.59%, 74.94%, 69.68%, and 54.41% after rotating three different crops(R3 treatment). The root volatiles of three plants inhibited mycelial growth and spore germination of four Fusarium species.
基金Supported by Natural Science Foundation of Inner Mongolia Autonomous Region (2020MS04001)Science and Technology Research Program of Hetao University (HYZX201952)Talent Introduction Startup Program of Hetao University (HYRC2019006)。
文摘[Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide a theoretical basis for maintaining the sustainable development of soil in Hetao Irrigation District. [Methods] The methods of experiment, questionnaire, on-the-spot investigation and literature review were used. [Results] This study proposed the empirical framework of washing salinity by irrigation to maintain soil quality in Hetao Irrigation District. Seven factors of the framework, including flood irrigation, land leveling, plastic film mulching, fertilization, soil organic matter, pH and salinity, and their relationships were determined. The characteristics of these factors in Hetao Irrigation District were investigated(flooding irrigation with a large amount of irrigation water, high amount of fertilizer application, low organic matter, high pH, large variation of salinity, etc.). The mechanisms and effects of various factors affecting soil quality in Hetao Irrigation District were analyzed(the mean soil organic matter(SOM) and pH were kept in the range of 10.9-13.9 g/kg and 8.0-8.15 in recent 35 years, respectively, and increased slightly, etc.). [Conclusions] The empirical framework can be used as a theoretical norm for evaluating soil quality under the condition of washing salinity by irrigation. Under the condition of washing salinity by irrigation, the agricultural soil quality in Hetao Irrigation District showed a stable trend over time. Using this framework, we can find soil problems, and adjust some unbalanced factors to maintain the stability of soil quality in Hetao Irrigation District, and can also provide a reference for other areas.
文摘For hydrocarbon polluted soils that underwent bioremediation it is important to assess its condition after a period of time, but it is more useful when there is an opportunity of comparison against an unpolluted soil and an untreated polluted one. This paper provides a comparison of three adjacent parcels, being the first clean, the second polluted and bioremediated, the third polluted and left to natural attenuation. Study was conducted determining pH, electrical conductivity, carbonates, soil organic matter, chemical oxygen demand, eight anions, and twelve metals. Data were compared against those references for agricultural soils found in the Mexican NOM-021. A Pearson correlation was applied to find coincidences between the three parcels, obtained results allowed to say that bioremediated parcel allowed for most uniform pH, negligible salinity risk, and medium content of soil organic matter, but treatment has enabled heavy metal accumulation since its values are higher in respect to the other parcels. Natural attenuated parcel has some spots with lower pH, a moderately saline risk, a high content of soil organic matter, and lower content of heavy metals. The clean or unaffected parcel exhibit the higher pH values, a slightly saline condition, soil organic matter ranges from high to very high content, heavy metals content is medium, but no reaching dangerous levels. An important assessment is that bioremediation has enhanced the bioavailability of soil organic matter but it is not similar to the values in the unpolluted parcel.
文摘The study examined the impacts of urbanization-related activities on soil quality in Port Harcourt Metropolis-Rivers state,Nigeria.Experimental and survey research designs were implored in the study utilizing GIS and spatial analysis approaches.Both primary and secondary sources of data were used.The primary data were generated through laboratory analysis of soil samples from 15 randomly selected sites within the metropolis;and 800 valid copies of socio-economic questionnaire administered to 800 respondents.Also,public hospitals were visited to ascertain the commonest soil borne diseases in the area.Four research questions,four specific objectives and two hypotheses guided the study.The hypotheses were tested with one sample t-test and one sample chi square using SPSS.Standard scientific and laboratory procedures were followed in the collection and analysis of soil samples.Findings of the study include:urbanization-related activities(e.g.waste dumpsites,mechanic workshops,abattoirs,etc.)cause significant changes on soil quality in the area;and this result to the emergence of soil borne diseases(e.g.Vascular witts,Ascaris lumbricoids,Trichuris trichiura,Strongloids stereoralis)which affects residents’wellbeing.However,there is significant difference in the perceived socio-economic effects of the diseases across the area.Specifically,laboratory results for soil analysis show that(mean values):pH 7.22,temperature 25.62℃,PO_(4)0.342 mg/kg,Pb 120.62 mg/kg,K 66.81 mg/kg,NO_(3)mg/kg.The study recommended for enforcement of physical planning and development control laws;regular evaluation of the quality of the soil,and restriction on the location of mechanic workshops and waste dumpsites around the metropolis.
基金Supported by Key Field Project of Education Department of Guizhou Province(QJHKYZ[2021]044)Forestry Research Project of Guizhou Province(QLKH[2021]11)+1 种基金Project of Guizhou Provincial Characteristic Key Laboratory(QJHKY[2021]002)National Natural Science Foundation of China(41761010).
文摘[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient element content and metabolites of C.oleifera.C.oleifera was inoculated with the suspension of Fusarium sp.in pot experiments and ammonium-N,available phosphorus,available potassi-um,organic matter,enzymes and pH of rhizosphere soil,MDA content,activity of SOD,POD of C.oleifera leaves were analyzed.[Results]Fusarium sp.stress significantly inhibited soil enzyme activities and significantly reduced available phosphorus content,especially for phospha-tase and sucrase.Antioxidant enzyme activities in C.oleifera tissues showed that Fusarium sp.stress significantly increased MDA and SOD enzyme activities and decreased POD enzyme activity.Especially,SOD enzyme activity was elevated by 53.86%compared with the CK group.In addition,analysis of the content of major metabolites in C.oleifera leaves showed that Fusarium sp.stress significantly reduced the content of total flavonoids,quercetin,isoquercitrin and isoquercitrin in C.oleifera leaves by 7.80%,50.00%and 75.90%,respectively.[Conclusions]Our results are an important step which showed strong resistance of C.oleifera and can give a novel insight for researches on the effects in the rhizosphere soil enzyme,soil nutrient elements and metabolites of C.oleifera under the Fusarium sp.too.
基金This study was supported by the National Key Research and Development Program of China(2016YFC0500602)the National Natural Science Foundation of China(No.41877047).
文摘Grasslands provide a number of ecosystem services for human society.Degradation of grasslands results in the loss of biodiversity and leads to the deterioration of ecosystem functions.In order to accurately assess the influence of grassland degradation on belowground ecosystems,we conducted experiments on a temperate steppe with different levels of degradation and investigated the influence of degradation on soil quality and soil biotic communities.Our results showed that grassland degradation significantly decreased soil quality,with lower values of soil quality index(SQI)observed in the degraded grassland than the meadow steppe and the grassland from the forest-steppe ecotone.Changes in the SQI along the grassland degradation gradient were positively correlated with soil carbon stock and the aboveground biomass,and negatively correlated with the root shoot ratio.Nematode trophic diversity and the ratio of fungal to bacterial PLFA were lower in the degraded grassland than the grassland from the forest-steppe ecotone.The dissimilarities in soil microbial and nematode community composition increased with the changes in soil quality index.Our results indicate that soil quality index based on the minimum data sets could effectively assess the influence of grassland degradation on soil biodiversity and ecosystem function.In order to effectively restore degraded grasslands,the key contributors to the soil quality,such as soil carbon,should be taken on priority basis for revitalizing the soil biodiversity and ecosystem function.
基金the National Natural Science Foundation of China(41630858)the National Key Research and Development Program of China(2017YFC0505404)the National Natural Science Foundation of China(41771304).
文摘Understanding the influence of collapsing gully management restoration on soil quality and function is essential to the protection of the regional ecological environment in the collapsing gully erosion area.The primary objective of this study was to construct soil quality index(SQI)to assess the influence of different vegetation restoration types on soil quality in collapsing gully restoration.The influence of five vegetation restoration types on soil properties was investigated by using a path analysis,a comprehensive soil quality index(SQI),and a general linear model(GLM).Vegetation restoration was shown to significantly increase the saturated hydraulic conductivity(Ks),mainly due to the effect of the physical parameters of bulk density,soil cohesion,and soil water content.Meanwhile,pH,Ks,soil organic matter(OM),and sand content were revealed as reasonable indicators to evaluate the influence of vegetation restoration on soil quality.Moreover,vegetation restoration was found to significantly improve the soil quality,with the highest SQI value for natural restoration mixed forest(NF),followed by replanted arboreal forest(RA)and replanted scrubland(RS),which were all significantly higher than the SQI value of the erosion area(EA)in the collapsing gully.Additionally,vegetation type explained the most substantial proportion of total variability(46.41%),and restoration time showed a positive correlation with SQI.The results of this study can provide a reference for the restoration and protection of the regional ecological environment in the collapsing gully area.
基金File no.16-6(Dec 2018)/2019(NET/CSIR)provided by the CSIR-UGC,Government of India,Nationality Eligibility Test.
文摘Background:Shifting cultivation is a major agriculture practice in the Nagaland state of India.This study examines the effect of shifting cultivation and the length of the fallow period on soil quality index(SQI).Four sites were selected for the study,viz.,a shifting cultivation site(SCS),a 3-year-old fallow land(FL-3),a 7-year-old fallow land(FL-7),and a 12-year-old fallow land(FL-12).Soil parameters were recorded seasonally and SQI was calculated from the minimum data set.Results:With the increase in the fallow period,the values of conductivity,soil organic carbon,available nitrogen,available phosphorus,exchangeable potassium,moisture,clay,and cation exchange capacity of soil increased.Meanwhile,soil pH and bulk density decreased with fallow duration.The additive SQI_(a)values were in the order SCS<FL-3<FL-12<FL-7;meanwhile,the weighted SQI_(w)values were in the order SCS<FL-3<FL-7<FL-12.It is also observed that the SQI value decreases with the increase in soil depth under both the weighted and additive indexes.SCS with the lowest SQI value reflects the reduced soil organic carbon(SOC)and macronutrients.Increased SOC levels in site FL-12(2.88–3.94%)may be one reason for its higher SQI value.Conclusions:Our study highlights that unsustainable practices of shifting cultivation and reduction in the fallow period negatively affect soil quality.Furthermore,the study also recommends the use of the weighted method of SQI as it agrees with the reports of land use causing alteration in the soil quality.Our findings may be utilized to quickly access and disseminate information to the stakeholders and aid in constructing local soil quality index maps of the region.There is an urgent need for a rapid,cost and resource-efficient soil quality assessment and SQI may be one tool that achieves this goal.
文摘Reuse of industrial wastewater(effluent)for irrigation purpose is a common practice.However,lack of adequate treatment of the effluent can cause soil deterioration,vegetation destruction and contamination of the aquatic environment.These adverse effects necessitated the study of wastewater irrigation in Emene Industrial Layout,Enugu State,Nigeria.Wastewater and soil samples were collected,analyzed and subjected to Analysis of Variance(ANOVA)for Completely Randomized Design(CRD)at 5% probability level using GENSTAT software.The results obtained from the study were compared with FAO soil and water standards.The wastewater analysis suggested that contamination at the untreated stage was very high and results at the treatment level were within the FAO reuse range.The study also found wide variation in chemical status of industrial wastewater treated soil.Almost all the values for the wastewater treated soil were not within the FAO irrigated soil chemical properties standards.This suggests high re-contamination along the open channel(from non-point sources)before reuse.This calls for proper monitoring and treatment of the industrial effluent prior to irrigation application.
基金This study was supported by the Program for the National Key Research and Development Program of China(2017YFD0801404 and 2016YFD0300808)the Youth Fund of Beijing Academy of Agriculture and Forestry Sciences(QNJJ201717)Youth Innovation Promotion Association CAS(NO.2017073).
文摘Vegetable greenhouses form a significant land utilisation pattern in China.A case study of the greenhouse soil quality changes and potential risk to humans under a specific long-term environment,which includes high fertilization rates,high temperatures and humidity levels and out-of-season cultivation,is presented in this study.Soil profiles of 72 representative solar greenhouses with various planting years were sampled in Shouguang City,which is the birthplace of winter greenhouse in China.The temporal distribution of soil quality changes were quantitatively evaluated through the application of a correlation analysis and soil quality assessment.The soil was highly enriched with phosphorus and potassium and had low organic matter content.The organic matter,nitrogen,phosphorus and potassium contents increased with the years planted,reached their peak values after 5-10 a,and declined as the soil layer’s depth increased.The infiltration rate of nitrate was relatively high,which poses risks to underground water safety.A comprehensive soil quality assessment revealed that in vegetable greenhouses planted for different periods,the soil quality improved at first and then sharply declined after 10 a.Studying greenhouse soil quality changes will aid in implementing nutrient management strategies to improve the soil quality and sustainable development programs for the vegetable industry.
基金the National Key Research and Development Program of China(2021YFD1500801)the National Natural Science Foundation of China(42177321).
文摘There have been many studies on soil quality and crop yield using different biochar application amounts,but few studies have focused on the combination of different methods and amounts of biochar application in moderately degraded Mollisols.In this study,the methods of mixing biochar evenly with the soil of the plough layer(0-20 cm depth)[homogeneous biochar application(HO)]and burying biochar above the soil plow pan(under 20 cm depth)(heterogeneous biochar application(HE))were used to reveal how biochar application methods influenced soil quality,crop yield and agronomic characteristics in moderately degraded Mollisols(soil organic matter(SOM),30.33 g kg^(−1)).The biochar application amounts were 0(control),10(level 1),20(level 2),and 40(level 3)t ha^(−1)in both the HO and HE treatments.The results showed that,compared with control,HO3 significantly increased maize yield in the first year,and HO2,HO3,HE2 and HE3 continuously increased maize yield in the next three years but not significantly.HO1 and HE1 had the lowest maize yield.HO2 tended to delay maize leaf senescence.There was a posi-tive linear relationship between soil quality index(SQI)and biochar application amount in HO.Compared with other treatments,the pH,EC,SOM,available phosphorus,sucrase and catalase activities were highest in HO3.However,the effects of HE on soil quality and crop productivity were limited at first but gradually increased with time.Overall,HO3 was beneficial for improving the soil quality and crop productivity in Mollisols for short-term cultivation(3-year),while HE showed an effect over time.
基金supported by the National Natural Science Foundation of China(Grant No.41931293)the National Key Research and Development Program of China(Grant No.2017YFC0504701)。
文摘Increasing the quantity and improving the quality of cropland can alleviate the human-land contradiction and promote the sustainable development of agriculture especially in mountainous areas.With the support of the central government’s policies,Yan’an,Northern Shaanxi,China implemented a major land consolidation engineering project in the loess hilly-gully region from 2013 to 2018,achieving 33,333.3 ha of new cropland.However,the poor quality of some newly-constructed cropland at the initial stage hindered its efficient utilization.In order to overcome this problem,red clay and Malan loess were compounded in different volume ratios to explore the method to improve the cropland quality.The Root Zone Water Quality Model was used to simulate the effects of different soil treatments on soil water,nitrogen and maize growth.Experimental data were collected from 2018 to 2019 to calibrate and validate the model.The root mean square error(RMSE)of soil water content,nitrate nitrogen concentration,above-ground biomass,leaf area index were in the range of 11.72-14.06 mm,4.06-11.73 mg kg^(-1),835.21-1151.28 kg ha^(-1)and 0.24-0.47,respectively,while the agreement index(d)between measured and simulated values ranged from 0.70 to 0.96.It was showed that,compared with land constructed with Malan loess only(T1),the soil structure and hydraulic characteristics of land with a volume ratio of red clay and Malan loess of 2:1(T3)was better.Simulation indicated that,compared with T1,the soil water content and available water content of T3 increased by 14.4%and 19.0%,respectively,while N leaching decreased by 16.9%.The aboveground biomass and maize yield of T3 were 7.9%and 6.7%higher than that of T1,respectively.Furthermore,the water productivity and nitrogen use efficiency of T3 increased by 21.0%and 16.6%compared with that of T1.These results indicated that compounding red clay and Malan loess in an appropriate ratio was an effective method to improve soil quality.This study provides a technical idea and specific technical parameters for the construction or improvement of cropland in loess hilly-gully region,which may also provide reference for similar projects in other places.
