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Effects of organic matter on the distribution of rare earth elements in red soil aggregates during ecological restoration

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Journal of Mountain Science 2021年第11期18卷 2915-2928页

作者： OU Xiao-lin CHEN Zhi-biao CHEN Zhi-qiang LIANG Mei-xia CHEN Hai-bin Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education Fujian Normal UniversityFuzhou 3500007China School of Geographical Sciences Fujian Normal UniversityFuzhou 3500007China

Rare earth elements(REEs)are widely applied in high-tech ***,their increasing presence in the food chain poses significant risks to human *** present,little is known about the effects of organic matter on the distribution of ion-adsorbed REEs in soil aggregates during ecological *** soil derived from coarse-grained granite in Southern China is both prone to ecosystem degradation from soil erosion and rich in *** the distribution of REEs in soil aggregates undergoing ecological restoration is helpful to formulate effective measures for controlling the environmental migration of *** sites that had undergone different durations/degrees of ecological restoration were selected in the areas to *** concentration of six different aggregates sizes(5 mm)were analyzed and the enrichment coefficients were calculated in 4 sample sites of severe-degraded ecosystem in Changting County,Fujian Province,Southern *** results showed that the total rare earth elements(TREEs)concentration in the aggregates increased from 213 mg kg^(-1) to 528 mg kg^(-1) with the extension of the ecological restoration *** the initial stages of ecological restoration,there was no significant difference in the TREEs concentration among the six aggregates ***,in the middle and late stages of restoration,the concentration of TREEs increased significantly with the decrease of aggregate *** concentration of individual REEs showed three changing trends with sizes of aggregates during ecological restoration,respectively:1)no obvious regular change(S1),2)a V-shaped change trend(S2),and 3)increasing concentration with the decrease of aggregate size(S3 and S4).Ce and Eu showed a positive and negative anomaly in the soil aggregates,***,the light rare earth elements(LREEs)were enriched,while the heavy rare earth elements(HREEs)were depleted during the initial stages,and the HREEs were

关键词： Rare earth elements soil aggregates Ecological restoration red soil

Spatial variability of soil organic carbon and total nitrogen in the hilly red soil region of Southern China

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Journal of Forestry Research 2020年第6期31卷 2385-2394页

作者： Xiong Yao Kunyong Yu Yangbo Deng Jian Liu Zhuangjie Lai College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002China University Key Lab for Geomatics Technology and Optimize Resources Utilization in Fujian Province Fuzhou 350002China

To obtain accurate spatial distribution maps of soil organic carbon(SOC)and total nitrogen(TN)in the Hetian Town in Fujian Province,China,soil samples from three depths(0–20,20–40,and 40–60 cm)at 59 sampling sites were sampled by using traditional analysis and geostatistical *** SOC and TN ranged from 2.26 to 47.54 g kg-1,and from 0.28 to 2.71 g kg-1,*** coefficient of variation for SOC and TN was moderate at 49.02–55.87%for all *** to the nuggetto-sill ratio values,a moderate spatial dependence of SOC content and a strong spatial dependence of TN content were found in different soil depths,demonstrating that SOC content was affected by both extrinsic and intrinsic factors while TN content was mainly influenced by intrinsic *** of cross-validation,such as mean error,mean standardized error,were close to zero,indicating that ordinary kriging interpolation is a reliable method to predict the spatial distribution of SOC and TN in different soil *** using ordinary kriging indicated the spatial pattern of SOC and TN were characterized by higher in the periphery and lower in the *** improve the accuracy of spatial interpolation for soil properties,it is necessary and important to incorporate a probabilistic and machine learning methods in the future study.

关键词： SOC TN Spatial variability Geostatistics red soil

Influence of Exogenous Lanthanum on Fertility Parameters of red soil and Paddy soil

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Journal of Rare Earths 2001年第3期19卷 229-232页

作者：谢祖彬朱建国褚海燕曾青张雅丽曹志洪 Chinese Acad Sci Inst Soil Sci Lab Mat Cycling Pedosphere Nanjing 210008 Peoples R China

The effects of exogenous La on the fertility parameters such as cation exchange capacity ( CEC), exchangeable basic cations, and exchangeable acidity in red soil and paddy soil were studied with soil column simulation. The results show that with increasing amount of the added La, the proportion of exchangeable La in soils increases and there is more exchangeable La in red soil than in paddy soil. When the concentration of La is more than 600 mg(.)kg(-1) the proportion of exchangeable La almost remains constant. When the concentration of La is less than 1200 mg(.)kg(-1) there is no significant effect on CEC in red soil. But when the concentration of La is more than 1200 mg(.)kg(-1,) it has significant effect on CEC in paddy soil. The application of La resulted in increasing exchangeable aluminum, Ca and Mg in soil solution, and decreasing exchangeable Ca and Mg retained in soils. But when the concentration of La is less than 150 mg(.)kg(-1), it has no significant influence on CEC, exchangeable Ca and Mg, and exchangeable acidity in red soil and paddy soil.

关键词： rare earths lanthanum fertility red soil paddy soil

Mechanistic insights into the synergetic remediation and amendment effects of zeolite/biochar composite on heavy metal-polluted red soil

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 105-114页

作者： Jing Li Dazhong Yang Wensong Zou Xuezhen Feng Ranhao Wang Renji Zheng Siyuan Luo Zheting Chu Hong Chen State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution ControlSchool of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

red soil,the most critical soil resource in tropical/subtropical regions worldwide,faces tremendous threats,including nutrient deficiency,acidification,and heavy metal *** is a great demand for multifunctional eco-materials capable of modifying this ***,we used widely distributed soil and biomass to develop a zeolite/biochar composite for synergistic red soil remediation and *** the composite material,the Pb^(2+) and Cd^(2+) remediation efficiencies reached 92.8%and 92.9%,respectively,in stems under optimal ***,the acidity and nutrient deficiency conditions of red soil significantly *** atomic-scale interaction mechanism during the remediation and amendment process was elucidated with complementary characterization methods,which revealed that in the zeolite/biochar composite material,zeolite contributes to longterm heavy metal remediation ***,biochar is responsible for soil quality amendment and short-term heavy metal ***,for the first time,single-atom heavy metal ions were observed on biochar during the remediation process,indicating the broad distribution of single atoms in the natural environment.

关键词： red soil Heavy metal pollution Zeolite/biochar composite soil remediation soil amendment

Effect of Lanthanum on Nitrification, Phosphorus Transformation and Phenol Decomposition in red soil

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Journal of Rare Earths 2002年第1期20卷 67-70页

作者：褚海燕朱建国谢祖彬李振高曹志洪曾青 Laboratory of Material Cycling in Pedosphere Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effect of La on nitrification, P transformation and phenol decomposition in red soil was studied by incubation and pot culture experiments. La at low concentration has stimulative effect on soil nitrification and P transformation while its high concentration has inhibitory effects, and the inhibition is strengthened with increasing concentration of La. La has strongly inhibitory effect on soil phenol decomposition and the inhibition is strengthened with increasing concentration of La. When the incubation time is prolonged, the inhibitory effect of La on soil nitrification and phenol decomposition tends to decrease.

关键词： rare earths lanthanum red soil nitrification phosphorus transformation phenol decomposition

Interaction of Cd and citric acid, EDTA in red soil

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Journal of Environmental Sciences 2001年第2期13卷 153-156页

作者： ZHOU Dong mei WANG Shen-qiang CHEN Huai man Laboratory of Material Cycling in Pedosphere Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Adsorption and desorption process of cadmium in red soil (Ferrisols) as well as the influence by media' s pH were investigated in detail with and without citric acid and EDTA. Experimental results clearly showed that Cd adsorption in red soil was affected significantly by the coexisted organic chemicals. In the presence of citric acid and EDTA, Cd adsorption in red soil increased with pH in acid media but decreased in high pH one. Further studies placed stress on the adsorbed Cd in red soil which was found to be existed mainly as exchangeable one at pH < 5.5, and desorption rate by 0.10 mol/L NaNO3 gave a peak-shaped curve due to the difference of specifically and nonspecifically adsorbed Cd with pH's change.

关键词： cadmium interaction organic acid red soil

Water and heat transport in hilly red soil of southern China:II. Modeling and simulation

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第5期6卷 338-345页

作者：吕军黄志珍韩晓非 School of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 China

Simulation models of heat and water transport have not been rigorously tested for the red soils of southern China. Based on the theory of nonisothermal water-heat coupled transfer, a simulation model, programmed in Visual Basic 6.0, was developed to predict the coupled transfer of water and heat in hilly red soil. A series of soil column experiments for soil water and heat transfer, including soil columns with closed and evaporating top ends, were used to test the simulation model. Results showed that in the closed columns, the temporal and spatial distribution of moisture and heat could be very well predicted by the model, while in the evaporating columns, the simulated soil water contents were somewhat different from the observed ones. In the heat flow equation by Taylor and Lary (1964), the effect of soil water evaporation on the heat flow is not involved, which may be the main reason for the differences between simulated and observed results. The predicted temperatures were not in agreement with the observed one with thermal conductivities calculated by de Vries and Wierenga equations, so that it is suggested that Kh, soil heat conductivity, be multiplied by 8.0 for the first 6.5 h and by 1.2 later on. Sensitivity analysis of soil water and heat coefficients showed that the saturated hydraulic conductivity, KS, and the water diffusivity, D(θ), had great effects on soil water transport; the variation of soil porosity led to the difference of soil thermal properties, and accordingly changed temperature redistribution, which would affect water redistribution.

关键词： red soil Coupled transfer of soil water and heat Simulation model Validation Sensitivity analysis

Effect of Different Vegetation Systems on soil Erosion and soil Nutrients in red soil Region of Southeastern China

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Pedosphere 2003年第2期13卷 121-128页

作者： S. KUMAR Department of Environmental Engineering Environmental Science and Resources College of Zhejiang University

The effect of different vegetation systems including bamboo plantation (BP), forest ecosystem (CF),citrus orchard (Ctr) and farmland (FL) on erosion and nutrients of red soil were investigated in hilly region of southeastern China to find effective control measures for soil erosion. The results showed that all the vegetation systems could significantly reduce soil erosion and nutrient losses compared to bare land (Br).The ability of different vegetation systems to conserve soil and water was in the order of Ctr ＞ BP ＞ CF ＞ FL ＞ Br. Vegetation could also improve soil fertility. The soil organic matter, total N and total P contents were much higher in all the vegetation systems than in bare land, especially for the top soils. Vegetation systems improved soil physical properties remarkably. Compared to the bare land, soil organic matter, TP,TK and available K, especially soil microbial biomass C, N and P, increased under all the vegetation ***, they were still much lower than expected, thus these biological measurements are still needed to be carried out continuously.

关键词： microbial biomass nutrients red soil soil erosion vegetation systems

Crop Yield and soil Responses to Long-Term Fertilization on a red soil in Southern China

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Pedosphere 2009年第2期19卷 199-207页

作者： ZHANG Hui-Min WANG Bo-Ren XU Ming-Gang FAN Ting-Lu Key Laboratory of Plant Nutrition and Nutrient Cycling Ministry of Agriculture of China and Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Department of Resource and Environment Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China Department of Agronomy Henan University of Science and Technology Luoyang 471003 China

A 15-year fertilization experiment with different applications of inorganic N,P and K fertilizers and farmyard manure (M)was conducted to study the yield and soil responses to long-term fertilization at Qiyang,Hunan Province,China. Average grain yields of wheat and corn(1 672 and 5 111 kg ha-1,respectively)for the treatment NPKM were significantly higher than those(405 and 310 kg ha-1)of the unfertilized control and single inorganic fertilizer *** with the corresponding initial values of the experiment,all treatments showed a yield decline of 9 to 111 kg ha-1 year-1 in wheat and 35 to 260 kg ha-1 year-1 in corn,respectively,and a significant pH decline of 0.07 to 0.12 pH year?1,except for the treatments PK and *** long-term fertilization,the soil organic C,soil available P,exchangeable Ca2+ and Mg2+and available Cu2+and Zn2+contents were higher in the treatment NPKM than in the treatments applied with inorganic fertilizer *** to the treatment NPK,the treatment NPKM,where manure partially replaced inorganic N,had a positive impact on arresting the decline of soil *** improved grain yields of wheat and corn, suggesting that application of NPK fertilizer in combination with farmyard manure is important to maintain soil fertility and buffering capacity in red soil.

关键词： corn long-term fertilization red soil wheat yield