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Optimized NPK fertilizer recommendations based on topsoil available nutrient criteria for wheat in drylands of China
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作者 Wenjie Yang Jie Yu +9 位作者 Yanhang Li Bingli Jia Longgang Jiang Aijing Yuan Yue Ma Ming Huang Hanbing Cao Jinshan Liu Weihong Qiu Zhaohui Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2421-2433,共13页
The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical fertilizers.Critical nutrient values can be used for evaluating the nutritional status... The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical fertilizers.Critical nutrient values can be used for evaluating the nutritional status of a crop,and they reflect the nutrient concentrations above which the plant is sufficiently supplied for achieving the maximum potential yield.Based on on-farm surveys of 504 farmers and 60 field experimental sites in the drylands of China,we proposed a recommended fertilization method to determine nitrogen(N),phosphorus(P),and potassium(K)fertilizer input rates for wheat production,and then validated the method by a field experiment at 66 different sites in northern China.The results showed that wheat grain yield varied from 1.1 to 9.2 t ha^(-1),averaging 4.6 t ha^(-1),and it had a quadratic relationship with the topsoil(0-20 cm)nitrate N and soil available P contents at harvest.However,yield was not correlated with the inputs of N,P,and K fertilizers.Based on the relationship(exponential decay model)between 95–105%of the relative yield and topsoil nitrate N,available P,and available K contents at wheat harvest from 60 field experiments,the topsoil critical nutrient values were determined as 34.6,15.6,and 150 mg kg^(-1)for soil nitrate N,available P,and available K,respectively.Then,based on five groups of relative yield(>125%,115–125%,105–115%,95–105%,and<95%)and the model,the five groups of topsoil critical nutrient levels and fertilization coefficients(Fc)were determined.Finally,we proposed a new method for calculating the recommended fertilizer input rate as:Fr=Gy×Nr×Fc,where Fr is the recommended fertilizer(N/P/K)input rate;Gy is the potential grain yield;Nr is the N(N_(rN)),P(N_(rP)),and K(N_(rK))nutrient requirements for wheat to produce 1,000 kg of grain;and Fc is a coefficient for N(N_c)/P(P_c)/K(K_c)fertilizer.A 2-year validated experiment confirmed that the new method reduced N fertilizer input by 17.5%(38.5 kg N ha^(-1))and P fertilizer input by 43.5%(57.5 kg P_(2)O_(5) ha^(-1))in northern China and did not reduce the wheat yield.This outcome can significantly increase the farmers’benefits(by 7.58%,or 139 US$ha^(-1)).Therefore,this new recommended fertilization method can be used as a tool to guide N,P,and K fertilizer application rates for dryland wheat production. 展开更多
关键词 fertilization method dryland wheat soil nutrient critical value soil nitrogen topsoil nutrients
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Spatio-temporal variations in organic carbon density and carbon sequestration potential in the topsoil of Hebei Province, China 被引量:5
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作者 CAO Xiang-hui LONG Huai-yu +4 位作者 LEI Qiu-liang LIU Jian ZHANG Ji-zong ZHANG Wen-ju WU Shu-xia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第11期2627-2638,共12页
Reliable prediction of soil organic carbon(SOC) density and carbon sequestration potential(CSP) plays an important role in the atmospheric carbon dioxide budget. This study evaluated temporal and spatial variation... Reliable prediction of soil organic carbon(SOC) density and carbon sequestration potential(CSP) plays an important role in the atmospheric carbon dioxide budget. This study evaluated temporal and spatial variation of topsoil SOC density and CSP of 21 soil groups across Hebei Province, China, using data collected during the second national soil survey in the 1980 s and during the recent soil inventory in 2010. The CSP can be estimated by the method that the saturated SOC content subtracts the actual SOC associated with clay and silt. Overall, the SOC density and CSP of most soil groups increased from the 1980 s to 2010 and varied between different soil groups. Among all soil groups, Haplic phaeozems had the highest SOC density and Endogleyic solonchaks had the largest CSP. Areas of soil groups with the highest SOC density(90 to 120 t C ha^(–1)) and carbon sequestration(120 to 160 t C ha^(–1)) also increased over time. With regard to spatial distribution, the north of the province had higher SOC density but lower CSP than the south. With respect to land-use type, cultivated soils had lower SOC density but higher CSP than uncultivated soils. In addition, SOC density and CSP were influenced by soil physicochemical properties, climate and terrain and were most strongly correlated with soil humic acid concentration. The results suggest that soil groups(uncultivated soils) of higher SOC density have greater risk of carbon dioxide emission and that management should be aimed at maximizing carbon sequestration in soil groups(cultivated soils) with greater CSP. Furthermore, soils should be managed according to their spatial distributions of SOC density and carbon sequestration potential under different soil groups. 展开更多
关键词 carbon sequestration SOC density spatial variation topsoil
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Distribution characteristics of total mercury and methylmercury in the topsoil and dust of Xiamen, China 被引量:3
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作者 LIANG Ying YUAN Dongxing +3 位作者 LU Min GONG Zhenbin LIU Xiyao ZFIANG Zhen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第10期1400-1408,共9页
The levels and distribution of mercury (Hg) species, including total mercury (THg) and methylmercury (MeHg) in the topsoil and dust collected from twenty sampling stations located in different land function area... The levels and distribution of mercury (Hg) species, including total mercury (THg) and methylmercury (MeHg) in the topsoil and dust collected from twenty sampling stations located in different land function areas of Xiamen, China, were investigated. The THg concentrations in topsoil ranged from 0.071 to 1.2 mg/kg, and in dust ranged from of 0.034 to 1.4 mg/kg. For stations where the THg of dust was less than 0.31 mg/kg, THg concentrations in the topsoil were significantly correlated to those in the corresponding dust (r = 0.597, n = 16, P = 0.014). The MeHg concentrations in topsoil were varied between 0.14 and 5.7 μg/kg. The ratios of MeHg/THg in the topsoil ranged from 0.069% to 0.74%. The range of MeHg concentration in the dust were 0.092-2.3 μg/kg. The ratios of MeHg/THg in the dust were at the same level as those in the topsoil. The MeHg concentrations in both topsoil and dust were linked to corresponding THg concentrations and soil organic matter. Neither THg nor MeHg concentration in the topsoil and dust was obviously linked to the land function. 展开更多
关键词 total mercury METHYLMERCURY topsoil DUST XIAMEN
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Storage and Density of Soil Organic Carbon in Urban Topsoil of Hilly Cities:A Case Study of Chongqing Municipality of China 被引量:7
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作者 LIU Yong WANG Cheng +1 位作者 YUE Wenze HU Yanyan 《Chinese Geographical Science》 SCIE CSCD 2013年第1期26-34,共9页
Rapid urbanization results in the conversion of natural soil to urban soil,and consequently,the storage and density of the soil carbon pools change.Taking Chongqing Municipality of China as a study case,this investiga... Rapid urbanization results in the conversion of natural soil to urban soil,and consequently,the storage and density of the soil carbon pools change.Taking Chongqing Municipality of China as a study case,this investigation attempts to better understand soil carbon pools in hilly cities.First,the vegetated areas in the study area were derived from QuickBird images.Then,topsoil data from 220 soil samples(0-20 cm) in the vegetated areas were collected and their soil organic carbon(SOC) densities were analyzed.Using the Kriging interpolation method,the spatial pattern of SOC was estimated.The results show that the SOC density exhibited high spatial variability in the urban topsoil of Chongqing.First,the SOC density in topsoil decreased according to slope in the order 2°-6° < 25°-90° < 0°-2° < 6°-15° < 15°-25°.Second,the newly developed areas during 2001-2010 had a lower SOC density than the areas built before 1988.Third,urban parks and gardens had a higher SOC density in topsoil,residential green land followed,and scattered street green land ranked last.For hilly cities,the variability of terrain affects the distribution of SOC.The Kriging results indicate that Kriging method combining slope with SOC density produced a high level of accuracy.The Kriging results show that the SOC density to the north of the Jialing River was higher than the south.The vegetated areas were estimated to amount to 73.5 km2 across the study area with an SOC storage of 0.192 Tg and an average density of 2.61 kg/m2. 展开更多
关键词 soil organic carbon (SOC) topsoil hilly city Kriging interpolation
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Geochemical baseline determination and contamination of heavy metals in the urban topsoil of Fuxin City,China 被引量:5
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作者 ZHANG Hua YU Miao +4 位作者 XU Hongjia WEN Huan FAN Haiyan WANG Tianyi LIU Jiangang 《Journal of Arid Land》 SCIE CSCD 2020年第6期1001-1017,共17页
Urban topsoil is the most frequent interface between human society and natural environment.The accumulation of heavy metals in the urban topsoil has a direct effect on residents'life and health.The geochemical bas... Urban topsoil is the most frequent interface between human society and natural environment.The accumulation of heavy metals in the urban topsoil has a direct effect on residents'life and health.The geochemical baseline of heavy metals is an objective description of the general level of heavy metals in the urban topsoil.Meanwhile,the determination of geochemical baseline is necessary for regional environmental management,especially in coal cities prone to heavy metal pollution.Heavy metal pollution has become an environmental problem in Fuxin City,China for a long time.To establish the geochemical baseline of heavy metals in the topsoil of Fuxin City and to evaluate the ecological risk of the topsoil,we collected 75 topsoil samples(0–20 cm)and analyzed the concentrations of Cu,Ni,Zn,Pb,Cr,Cd,Hg and As through X-ray fluorescence spectrometry,atomic absorption spectrometry and inductively coupled plasma optical emission spectrometry.We determined the geochemical baseline of heavy metals in the topsoil of Fuxin City by using iteration removal,box-whisker plot,cumulative frequency curve and reference metal normalization;evaluated the contamination risk and ecological risk of the topsoil by using the baseline factor index,Nemerow index and Hakanson potential ecological risk index;and identified the source category of heavy metals in the topsoil by using a pedigree clustering heatmap.Results showed that the geochemical baseline values were 42.86,89.34,92.23,60.55,145.21,0.09,0.08 and 4.17 mg/kg for Cu,Ni,Zn,Pb,Cr,Cd,Hg and As,respectively.The results of Nemerow index and Hakanson potential ecological risk index indicated that the urban topsoil in the study area was slightly contaminated and suffering low potential ecological risk.The main contaminated areas dominated in the middle part and northeast part of the study area,especially in the western Haizhou Strip Mine.The result of baseline factor index indicated that Hg and Cd were the major pollution elements.Using a pedigree clustering heatmap,we divided the sources of these heavy metals into three types:type I for Ni and Cr,largely represented the enrichment of heavy metals from natural sources;type II for Cu,Pb,Zn,Cd and As,mainly represented the enrichment of heavy metals from anthropogenic sources;and type III for Hg,represented the form of both natural and anthropogenic inputs. 展开更多
关键词 heavy metals urban topsoil geochemical baseline contamination index pedigree clustering heatmap
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Clomazone dissipation, adsorption and translocation in four paddy topsoils 被引量:1
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作者 LILian-fang LIGuo-xue +2 位作者 YANGRen-bin GUOZheng-yuan LIAOXiao-yong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期678-682,共5页
Laboratory experiments about the dissipation, adsorption and translocation in four paddy topsoils were conducted in this paper. From the results it can be concluded as follows: the dissipation rate of clomazone differ... Laboratory experiments about the dissipation, adsorption and translocation in four paddy topsoils were conducted in this paper. From the results it can be concluded as follows: the dissipation rate of clomazone differed greatly in different paddy soil derived from different parent materials. The half-lives for clomazone degradation in paddy soils ranged from 5.7 to 22.0 d. The order of clomazone dissipation rate was reddish yellow paddy soil > alluvial sandy paddy soil > yellow clayey paddy soil > purple sandy paddy soil. Clomazone sorption quantity was significantly correlated with organic carbon(R2=0.62) and clay content(R2=0.67) in the tested paddy soils. Positive correlation was found between apparent K d value and cation exchange content(CEC). The consequences for the adsorption of different soils were purple sandy paddy soil>yellow clayey paddy soil>reddish yellow paddy soil>alluvial sandy paddy soil. Under the simulated rainfall of 200 mm through four different unsaturated soil lysimeters over 24 h, clomazone was readily to be leached into lower surface soil and there was about 2.6%—4.2% of applied clomazone leached out of 20 cm cultivated soil layer. Translocation experiments showed that the order of clomazone leaching ability was: alluvial sandy paddy soil > reddish yellow paddy soil > yellow clayey paddy soil > purple sandy paddy soil. Simple regression results manifested that factors like CEC, organic carbon, clay, and adsorption rate constant had been negatively correlated with the percentage of clomazone loss from soil lysimeters. 展开更多
关键词 CLOMAZONE DISSIPATION ADSORPTION TRANSLOCATION paddy topsoils
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Effects of native and invasive Prosopis species on topsoil physiochemical properties in an arid riparian forest of Hormozgan Province,Iran 被引量:1
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作者 Maryam MOSLEHI JOUYBARI Asgahr BIJANI +2 位作者 Hossien PARVARESH Ross SHACKLETON Akram AHMADI 《Journal of Arid Land》 SCIE CSCD 2022年第10期1099-1108,共10页
Biological invasions can alter soil properties within the range of their introduced,leading to impacts on ecosystem services,ecosystem functions,and biodiversity.To better understand the impacts of biological invasion... Biological invasions can alter soil properties within the range of their introduced,leading to impacts on ecosystem services,ecosystem functions,and biodiversity.To better understand the impacts of biological invasions on soil,we compared topsoil physiochemical properties at sites with invasive alien tree species(Prosopis juliflora),native tree species(Prosopis cineraria,Acacia tortilis,and Acacia ehrenbergiana),and mixed tree species in Hormozgan Province of Iran in May 2018.In this study,we collected 40 soil samples at a depth of 10 cm under single tree species,including P.juliflora,P.cineraria,A.tortilis,and A.ehrenbergiana,as well as under mixed tree species.The results showed that organic matter,moisture,potassium,calcium,nitrogen,and magnesium in topsoil at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria were higher than that at sites where P.juliflora was present(P<0.05).Sodium at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria and P.juliflora was lower as compared to that at sites with just A.tortilis and A.ehrenbergiana.Electrical conductivity was lower at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria,and it was higher at sites with mixed Acacia and P.juliflora trees.Based on the generally more positive effect of native Acacia and P.cineraria on topsoil physiochemical properties as compared to the P.julifora,afforestation with native tree species is preferable for soil restoration.In addition,due to the negative effects of P.julifora on soil properties,P.julifora spread should be better managed. 展开更多
关键词 Prosopis juliflora Prosopis cineraria tree species INVASION topsoil physiochemical properties Iran
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Distribution of heavy metals in the topsoil of the Jining mining area 被引量:1
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作者 HAO Junliang HAN Zuozhen +2 位作者 WANG Cuizhen ZHOU Guangzhu LI Yinming 《Mining Science and Technology》 EI CAS 2010年第3期395-399,共5页
The geochemical baseline is the fundamental reference for environmental change and assessment.In this article we describe cluster and regression analyses with a normalization procedure.The elements Sc and Ag were chos... The geochemical baseline is the fundamental reference for environmental change and assessment.In this article we describe cluster and regression analyses with a normalization procedure.The elements Sc and Ag were chosen to calculate the environmental geochemical baseline.The geoaccumulation index was calculated and mapped to indicate the environmental quality of the soil.The results show that the urban areas are barely polluted with Ni and Cr but the rural areas in the southern part of the city, and the western part of the lake,are polluted with Ni,Cr,and Cu at the second level.On the other hand,the rural areas in the southern part of the city,and the western part of the lake,are polluted with As at a moderate level.The other area is polluted at the second level.An increase in As pollution occurs in a direction from northeast to southwest.The Cd pollution follows a trend similar to As,with an additional smaller contaminated area polluted at levelⅢ.The Hg pollution typical of urban areas occurs in the main and northern parts of the city.The geochemical accumulation index decreases from the city center to the periphery.The highest pollution level reaches levelⅣ,which indicates that the soil is seriously polluted with Hg.The southern part of the city and the rural areas to the west of the lake are not contaminated with Hg.Geological factors and the disturbance from human activities are both possible major factors:further research is needed to identify them. 展开更多
关键词 geochemical baseline heavy metal geoaccumulation index topsoil
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Characterization of Topsoil Samples and Analysis of the Distribution of Heavy Metals in Parral Chihuahua, Mexico 被引量:1
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作者 L. Rodriguez Vazquez H. Ferman Avila +7 位作者 E. Torres Carrillo L. Shenz Macias J. Luna Carrete E. Herrera G.GonzSlez D. Aranda Caro J. Carrillo L. Lozoya 《Journal of Environmental Science and Engineering》 2010年第12期12-17,共6页
During the 17th Century, Parral City in the Chihuahua State in Mexico was one of the most important miner zones in the whole world. After more than three centuries important amounts of residuals, known as tailings, wi... During the 17th Century, Parral City in the Chihuahua State in Mexico was one of the most important miner zones in the whole world. After more than three centuries important amounts of residuals, known as tailings, with high contents of heavy metals were generated. These residuals are a potential risk for the environment and human health. Given to that, it decided to carry out the analysis of the concentrations of cadmium, lead, chromium, zinc and arsenics, in topsoil samples susceptible of airborne transport and accumulation in risky zones (populated areas). A 120 kin: area was selected, this include Parral City and its surroundings. From this area 30 samples were obtained. For this purpose, Atomic Absorption Spectroscopy technique was used, expecting high concentrations of heavy metals, above the permit limits, since several studies carried out in the same region, as in San Francisco del Oro Chihuahua, show that the concentrations of all the elements sampled, in topsoil, were above the limits. The analysis in the space distribution of the heavy metal detected will allow us to set the points with the highest susceptibility to the accumulation of those pollutants and to propose mitigation measures and control. 展开更多
关键词 Heavy metals mining activity topsoil
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Morphological Characteristics and Environmental Implications of Phytoliths in Topsoils from Different Vegetation Zones on Northern Slope of Changbai Mountains,China
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作者 QIAO Zhihe JIE Dongmei +2 位作者 LIU Hongmei GE Yong ZHANG Hongyan 《Chinese Geographical Science》 SCIE CSCD 2010年第6期506-512,共7页
The Changbai Mountains,located in the temperate monsoon climate zone of East Asia,is an ideal loca-tion for the research on timberline response to global changes.In this study,the topsoils were collected from differen... The Changbai Mountains,located in the temperate monsoon climate zone of East Asia,is an ideal loca-tion for the research on timberline response to global changes.In this study,the topsoils were collected from different vertical vegetation zones on the northern slope of the Changbai Mountains,Northeast China in August 2009,and phytoliths in the soil samples were extracted by using wet oxidation method and identified with Motic 2.0 microscope in laboratory.The results show that phytoliths are abundant in the topsoils of the study area.The herbal phytoliths are primarily composed of elongated,tooth-shaped,point-shaped and hat-shaped phytoliths,as well as a small amount of fan-shaped and square-shaped ones.The elongated,tooth-shaped,point-shaped and hat-shaped phytoliths are representative of cold climate,while fan-shaped and square-shaped ones are representative of warm and humid climate.In the conifer broadleaved mixed forest zone,coniferous forest zone and broadleaf forest zone,there are close correlations between vegetation and woody phytoliths in the topsoils,indicating that the woody plants of a region can be reconstructed from the woody phytolith assemblages in the topsoils.Meanwhile,the topsoil phytolith assemblages can also be used to reconstruct the understory herbs effectively.The phytolith assemblages in the topsoils of the forest community and herbal community differ significantly,which can help indicate the historical location of the timberline. 展开更多
关键词 topsoil phytolith TIMBERLINE environmental implication vertical vegetation zones Changbai Mountains
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Impact of natural disturbance, forest management and vegetation cover on topsoil biochemical characteristics of Tatra Mts.(Slovakia)
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作者 Jana GáFRIKOVá Milan ZVARíK +2 位作者 Peter HANAJíK Marek SúLOVSKY Ivana VYKOUKOVá 《Journal of Mountain Science》 SCIE CSCD 2020年第6期1294-1309,共16页
Perturbations caused by windstorms usually lead to the harvesting and clearcutting of fallen trees and wood debris,especially in the areas of managed forest ecosystems.Induced shifts in soils due to management practic... Perturbations caused by windstorms usually lead to the harvesting and clearcutting of fallen trees and wood debris,especially in the areas of managed forest ecosystems.Induced shifts in soils due to management practices play a crucial role in the restoration and maintaining of key ecosystem services.This paper focuses on topsoil chemical properties in relation to vegetation type(trees,shrubs and herbs)evolving at windstorm damaged(in 2004)areas with former Norway spruce(Picea abies)forests in the Tatra Mts.region(Slovakia).We assessed the content of topsoil organic matter fractions(extractives,holocellulose(HC)and lignin(Lig)),carbon in microbial biomass(Cmic),soil organic matter(SOM)and the content of elements N,C,H and S.The study plots represent different types of post-windthrow disturbance history/regime:wooden debris extraction(EXT),wooden debris not extracted(NEX),wooden debris extraction followed by wildfire(FIR),affected by the windstorm in 2014 with the subsequent wooden debris extraction(REX)and unaffected(REF).Our results revealed significant differences among sites in the content of dichloromethane extractives(EXT vs.REX and FIR),acetone extractives(NEX vs.EXT,FIR and REF),ethanol extractives(FIR vs.EXT,NEX and REF),water extractives(FIR vs.REX,NEX)and Cmic(EXT vs.NEX,FIR and REF).The topsoil of Vaccinium myrtillus and Picea abies showed a higher ratio of C/N,N/Lig,and Lig/HC compared to Rubus idaeus,Avenella flexuosa,Calamagrostis villosa,and Larix decidua.The content of N,C,H and S varied between topsoil with shrubs(Vaccinium myrtillus,Rubus idaeus)and grasses(Avenella flexuosa,Calamagrostis villosa).A positive correlation between soil organic matter(SOM)and polar extractives(r=0.81)and a negative correlation between SOM and HC(r=-0.83)was revealed.The carbon content in microbial biomass(Cmic)is positively correlated with acid soluble lignin(ASL)(r=0.85).We also identified a strong correlation between Klason lignin(KL)and the Lig/HC ratio(r=0.97). 展开更多
关键词 WINDTHROW WILDFIRE Organic matter fractions Vegetation type Norway spruce topsoil chemical properties
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Micro-morphological Features of Topsoil under Long-term Cultivation of Grain and Cotton Crops in Northwestern Shandong
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作者 Baohua ZHANG Ziting LIU +1 位作者 Jianrong CAO Baoxian TAO 《Asian Agricultural Research》 2018年第6期81-84,共4页
This study aimed to provide a basis for the rational improvement of the microstructure of the soil that had been planted with crops for a long time. Conventional and micro-morphological methods were used to study the ... This study aimed to provide a basis for the rational improvement of the microstructure of the soil that had been planted with crops for a long time. Conventional and micro-morphological methods were used to study the effects of planting grain and cotton crops on soil properties in Gaotang County,Shandong Province. The results showed that long-term cultivation of grain and cotton crops has a significant impact on soil micro-structure. The top soil( 0-10 cm) of wheat-maize field has higher organic matter content,uniform aggregate size,high separation,and strong packing void connectivity,forming a type micro-structure that is conducive to agricultural production. The characteristics of soil matrix are mainly inherited from soil parent materials,and the impact of crop cultivation on soil matrix is very weak. The amount of formations in the soil is less,and only Fe nodules,Mn nodules and excrement are observed. 展开更多
关键词 CROP topsoil Soil micro-morphology Gaotang County SHANDONG
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Brief Study on Microelement Contents in Topsoils of Farmlands in Xuancheng, South Anhui
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作者 Anqi Wang Ka Lin +9 位作者 Chengxin Ma Qin Gao Qifa Zhu Xuejun Ji Guo Zhang Lin Xue Chaolong Zu Chaoqiang Jiang Jia Shen Decheng Li 《Agricultural Sciences》 2018年第6期718-728,共11页
The available contents of microelements in the topsoil can influence the yield and quality of flue-cured tobacco. Xuancheng is the dominant tobacco-planting region in Anhui province since 2008. In this paper, the tops... The available contents of microelements in the topsoil can influence the yield and quality of flue-cured tobacco. Xuancheng is the dominant tobacco-planting region in Anhui province since 2008. In this paper, the topsoil available Fe, Mn, Cu and Zn contents of 4197 farmlands mainly under rice-rice rotation and wheat-rice rotation in 2008 and of 124 typical farmlands under tobacco-rice rotation in 2015 in Xuancheng city were analyzed in order to disclose the changes and spatial distributions of these microelements and to instruct the reasonable application of the microelement fertilizers. The results showed that the topsoil average available contents in the farmlands under rice-rice rotation or wheat-rice rotation in 2008 were 105.9 mg·kg-1 for Fe, 19.6 mg·kg-1 for Mn, 4.5 mg·kg-1 for Cu, and 3.0 mg·kg-1 for Zn, respectively, increased by 33.14%, 64.29%, 51.11% and 36.67%, respectively, compared with those in the 2nd Soil Survey in 1980s, and the historic, once intensive and overall application of microelement fertilizers was attributed to the great increases. The topsoil average available contents in the farmlands under tobacco-rice rotation in 2015 were 31.1 mg·kg-1 for Fe, 9.8 mg·kg-1 for Mn, 2.1 mg·kg-1 for Cu, and 0.3 mg·kg-1 for Zn, respectively, decreased by 70.63%, 50.00%, 53.33% and 90.00%, respectively, compared with those of the farmlands under rice-rice rotation or wheat-rice rotation in 2008, and the net deficiencies in the input and output of microelements were attributed to the significant decreases in the topsoil microelements. It is necessary to monitor the farmlands under tobacco-rice rotation dynamically and in time in order to decide whether applying microelement fertilizers or not. 展开更多
关键词 Microelement Available CONTENT topsoil of FARMLAND Xuancheng City
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Spatial distribution and risk assessments of mercury in topsoils of Central Asia
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作者 Zhengzheng Yang Junming Guo +7 位作者 Shiwei Sun Dingming Ni Pengfei Chen Dipesh Rupakheti Huhu Kang Sabur F Abdullaev Salamat Abdyzhapar uulu Shichang Kang 《Geoscience Frontiers》 SCIE CAS CSCD 2023年第4期270-279,共10页
Central Asia is one of the largest arid areas on earth,yet little is known about the concentration levels and risks of mercury(Hg)in the soils of this region.In this study,extensive sampling of topsoils(0-10 cm)from r... Central Asia is one of the largest arid areas on earth,yet little is known about the concentration levels and risks of mercury(Hg)in the soils of this region.In this study,extensive sampling of topsoils(0-10 cm)from representative landscapes was carried out over Central Asia(i.e.,Tajikistan,Uzbekistan,and Kyrgyzstan).The total mercury(THg)concentrations in topsoils varied widely from 1.6 to 908.0 ng/g,with high values observed in samples collected in the capital cities and urban areas.Topsoil THg concentrations among different landscapes showed a decreasing order of urban(79.8±184.0 ng/g)>woodland(27.3±28.9 ng/g)>grassland(20.6±15.9 ng/g)>farmland(18.3±9.5 ng/g)>desert(12.3±8.0 ng/g).High THg concentrations were found in the capital cities/urban clusters,followed by a gradual decrease towards the peripheries.THg concentrations were found to be negatively correlated with the distance from the sampling sites to their nearest cities,indicating that anthropogenic emissions significantly influenced the spatial distribution of topsoil Hg.A significant correlation between THg concentrations and topsoil total organic carbon(TOC)contents was also observed,suggesting that TOC played an essential role in the spatial distribution of topsoil Hg.The assessments of pollution and potential ecological risk suggested that topsoils in highly densely-populated areas were contaminated by Hg and had higher degrees of potential ecological risks.The health risk assessment results showed that the exposure risk of topsoil Hg to children was higher than that to adults.Fortunately,there was no unacceptable human health risk of topsoil Hg.This study clarified the spatial distribution and risks of Hg in the Central Asian topsoils,offering new insight into the risk prevention and control of soil Hg. 展开更多
关键词 MERCURY topsoil LANDSCAPE Spatial distribution Risk assessment Central Asia
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皖西大别山农耕区表层土壤养分地球化学综合评价及影响因素
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作者 董秋瑶 宋超 +3 位作者 温皓天 向娇 王攀 严明疆 《岩矿测试》 CAS CSCD 北大核心 2024年第2期344-355,共12页
土壤养分是影响农作物产量的重要指标,掌握中国主要农业生产区的土壤养分时空演变特征对合理使用农业土地资源具有重要的意义。本文以中国重要农耕区皖西大别山六安地区为研究区,采集浅层土壤(0~20cm)样品1295组,采用硫碳仪、X射线荧光... 土壤养分是影响农作物产量的重要指标,掌握中国主要农业生产区的土壤养分时空演变特征对合理使用农业土地资源具有重要的意义。本文以中国重要农耕区皖西大别山六安地区为研究区,采集浅层土壤(0~20cm)样品1295组,采用硫碳仪、X射线荧光光谱法、电感耦合等离子体发射光谱法等技术进行测试。应用统计学分析方法,在分析pH值的基础上,对总氮(TN)、总磷(TP)和钾(K)和土壤有机质(SOM)四个地球化学养分指标进行单指标养分等级划分和土壤养分综合等级评价,并探讨了各项指标的影响因素。结果表明:研究区98.88%的土壤为酸性土壤(其中8.03%为强酸性土壤),受地貌类型影响较大;TN分布以中等丰富为主,受土壤类型影响较大;TP以中等含量和缺乏为主,受地貌类型的影响较大;K是最为丰富的元素,其含量在中等及以上的比例达97.81%,主要受地貌类型的影响;SOM以中等和较缺乏为主,受土壤类型、土地利用方式和地貌类型的共同影响,且SOM含量与TN含量呈高度正相关。全区土壤养分等级以中等为主,占全区总面积的60.10%,其次是较缺乏土壤,占25.27%,南部山区养分状况优于北部平原区。整体上,研究区土壤具有养分较差、养分分布不均匀、普遍酸化的特点,部分地区应按需调整肥料的使用平衡土壤养分。可通过农田养分的管理,提高农业产量。 展开更多
关键词 表层土壤 电感耦合等离子体发射光谱法 土壤养分地球化学综合等级评价 土地利用方式 土壤类型 地貌类型
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Physicochemical composition and climate response of surface sediments at different altitudes in Motuo on the southern slope of the Himalayas
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作者 XIE Mengping SONG Yougui +2 位作者 LAN Minwen ZHANG Mingyu HAN Yixiao 《地球环境学报》 CSCD 2024年第4期624-640,共17页
Background,aim,and scope Certain physicochemical indexes of topsoil are closely related to climatic factors including temperature,and precipitation.Understanding the relationship between modern topsoil properties and ... Background,aim,and scope Certain physicochemical indexes of topsoil are closely related to climatic factors including temperature,and precipitation.Understanding the relationship between modern topsoil properties and climatic factors is essential for quantitative paleoclimate reconstruction.Motuo located in the eastern Himalayas,exhibits a significant elevation gradient of over 7000 m from Nnamjagbarwa Peak(7782 m a.s.l.)to the Baxika(150 m a.s.l.).This region features a complete vertical zonation of vegetation,from alpine meadow to tropical forest,presenting an ideal place to investigate the relationships among vegetation,soil and climate conditions across altitudinal gradients.This study aims to explore the vertical variations in the physicochemical composition of topsoil and its relationship with temperature and precipitation.Materials and methods Twenty-seven topsoil samples were collected at 100 m intervals from 800 m to 3600 m a.s.l.along the southern slope of the Himalayas.Grain size,magnetic susceptibility and geochemical elements were measured to discuss the vertical variation characteristics of topsoil composition and their correlation with climatic factors.Results(1)The grain size of topsoil at different altitudes in Motuo is mainly composed of sand accounting for an averaged 53.2%,followed by silt and clay.(2)In the mixed forest zone,frequency dependent magnetic susceptibility(χfd%)shows a clear relationship with altitude,and clay is positively correlated with both altitude and climatic factors.(3)The oxides of topsoil in this area mainly consist of SiO_(2),Al_(2)O_(3) and Fe_(2)O_(3),followed by MgO,CaO,Na_(2)O and K_(2)O,with slight variations in the primary components at different altitudes.The sensitivity of elements to climate varies across different altitudes and vegetation zone,likely due to the region’s complex topography and vegetation.(4)Physical and biological weathering dominates in the broad-leaved forest zone of Motuo,while chemical weathering is more prominent in the coniferous forest zone,with the mixed forest zone falling in between.Discussion The formation of topsoil across the three vegetation zones is influenced by various factors,including parent material,vegetation,and climate.In the broad-leaved forest zone,physical weathering(precipitation,root wedging etc.)and pedogenesis dominate,resulting in finer grain size.The χ_(fd)% increases with altitude likely due to the high temperature and abundant precipitation in this zone,which facilitate the transformation of strong magnetic miners into weaker ones,particularly when the soil is oversaturated.Zirconium(Zr),primarily found in zircon,is depleted at lower altitudes by strong current erosion.Barium(Ba)is similarly reduced at low altitudes in this zone.In mixed forest zone,clay content is the lowest,indicating weaker physical weathering conditions than broad-leaved forest zone.The coarser grain size may result from the combined effects of topography and vegetation coverage.Magnetic susceptibility and organic matter show a positive correlation with altitude.Zr concentration is higher than that in the broad-leaved forest zone,likely resulting from decreased precipitation.In the coniferous zone,the clay content shows considerable fluctuations,with grain size generally becoming finer as altitude increases.This trend may be explained by intensified soil disintegration from seasonal freeze-thaw cycles.The χ_(fd)% values lack a clear trend or pattern,possibly due to soil erosion causing the migration of magnetic minerals or insufficient iron precipitation,which reduces the concentration of magnetic minerals in the soil.Additionally,a positive correlation is observed between altitude and organic matter content,with higher altitudes associated with greater organic matter accumulation.This may be attributed to lower microbial activity in colder conditions,which slows the decomposition and transformation of organic matter.Conclusions The variations in grain size,magnetic susceptibility,and geochemical elements differ across altitudes and vegetation zones,closely connected to the complex interplay of terrain,vegetation,and climate in Motuo.In the mixed forest,altitude has a significant impact onχfd%,and the clay component is particularly sensitive to changes in altitude,mean annual temperature,and precipitation.Zr shows a strong correlation with altitude and climate factors,making it a valuable indicator for assessing changes in atmospheric precipitation within specific altitude ranges.Recommendations and perspectives This study enhances our understanding of the relationships between the physicochemical properties of topsoil and climate conditions,offering valuable insights for paleoclimate reconstruction in Motuo. 展开更多
关键词 southern slope of the Himalayas MOTUO topsoil altitude difference vegetation zone physicochemical indexes
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青藏高原表土磁化率空间分布特征及影响因素
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作者 陈雅敏 宋效东 +3 位作者 刘峰 叶明亮 张楚 张甘霖 《土壤学报》 CAS CSCD 北大核心 2024年第2期361-371,共11页
土壤磁化率是古环境重建的常用代用指标,对表土磁化率与现代环境的关系研究有助于理解磁化率产生差异的原因。当前,区域尺度上土壤磁化率变化成因认识尚不清楚,限制了磁化率作为古环境重建重要代用指标的精准应用。本研究系统调查了青... 土壤磁化率是古环境重建的常用代用指标,对表土磁化率与现代环境的关系研究有助于理解磁化率产生差异的原因。当前,区域尺度上土壤磁化率变化成因认识尚不清楚,限制了磁化率作为古环境重建重要代用指标的精准应用。本研究系统调查了青藏高原的254个样点表层(发生层A层)土样,测定土壤磁化率和其他土壤属性,结合母质、气候、地形和植被等数据,阐明青藏高原地区土壤磁化率空间变化特征及其主要影响因素。结果表明:(1)不同母质类型之间,表层土壤磁化率(χ_(lf))无显著差异,百分频率磁化率(χ_(fd)%)差异显著,表现为黄土和砂页岩风化物>冰碛物和结晶盐风化物,其他母质类型之间无显著差异;不同土地利用之间,表层土壤χ_(lf)无显著差异,χ_(fd)%差异显著:森林和旱地>草地>荒地。(2)各因子对土壤磁化率影响表现为植被>理化性质>地形>母质。(3)空间分布上,χ_(lf)与χ_(fd)%均呈现由东南向西北降低的趋势。此外,χ_(lf)和χ_(fd)%的空间分布规律与青藏高原植被分区相吻合。因此,磁化率能更好地指示植被空间分布。 展开更多
关键词 青藏高原 表土 磁化率 气候
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城市不同环境空间下PM_(2.5)及表层土壤细菌群落结构差异性研究
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作者 叶子葳 文建辉 +4 位作者 卢德林 林清钰 陈春强 霍强 龙腾发 《广西科学》 CAS 北大核心 2024年第3期523-531,共9页
为探究不同环境空间下空气微生物的组成特征和来源,在桂林城区与市郊选择8类典型的人类活动环境空间,分别采集大气细颗粒物(PM_(2.5))及表层土壤样本,利用高通量测序技术分析样本的细菌群落结构。结果表明:在不同环境空间下,PM_(2.5)样... 为探究不同环境空间下空气微生物的组成特征和来源,在桂林城区与市郊选择8类典型的人类活动环境空间,分别采集大气细颗粒物(PM_(2.5))及表层土壤样本,利用高通量测序技术分析样本的细菌群落结构。结果表明:在不同环境空间下,PM_(2.5)样本间的细菌群落结构差异性较小,表层土壤则表现出较明显的城区与市郊差异性,同一采样点的PM_(2.5)与表层土壤也表现出较大的差异性。PM_(2.5)与表层土壤中的主要细菌门为变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、绿弯菌门(Chloroflexi)、拟杆菌门(Bacteroidetes)及厚壁菌门(Firmicutes),其相对丰度总和超过80%。各个环境空间中的微生物群落差异均表明人类活动对微生物群落的影响较大。此外,不同环境空间中的优势菌属也有所不同,这与环境的特点、细菌的生态功能相关。PM_(2.5)中的优势菌属为异样根瘤菌属(Allorhizobium Neorhizobium Pararhizobium Rhizobium)、假双头斧形菌属(Pseudolabrys)、甲基杆菌属(Methylobacterium)和不动杆菌属(Acinetobacter),而表层土壤中的优势菌属为鞘氨醇单胞菌属(Sphingomonas)、异常球菌属(Deinococcus)、马赛菌属(Massilia)和酸杆菌门(Acidobacteria)下的Subgroup_6属。 展开更多
关键词 PM_(2.5) 表层土壤 细菌群落结构 来源分析 高通量测序
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长三角地区南京市表土重金属污染特征及源解析 被引量:3
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作者 杨昱莹 刘亮 +3 位作者 陈明 赖涓涓 王彦瑜 郝燕芳 《中国环境科学》 EI CAS CSCD 北大核心 2024年第7期3910-3918,共9页
以南京市主城区浅表层土壤为例,分析长三角地区典型工业城市土壤重金属Cd、Cr、Cu、Mn、Ni、Pb和Zn的污染特征,并用克里金法与多元统计分析法,解析土壤重金属来源.结果表明:南京市主城区土壤中Cd、Cr、Cu、Mn、Ni、Pb和Zn均存在富集现象... 以南京市主城区浅表层土壤为例,分析长三角地区典型工业城市土壤重金属Cd、Cr、Cu、Mn、Ni、Pb和Zn的污染特征,并用克里金法与多元统计分析法,解析土壤重金属来源.结果表明:南京市主城区土壤中Cd、Cr、Cu、Mn、Ni、Pb和Zn均存在富集现象,含量均值分别为0.24、76.9、36.45、707.22、35.48、32.65和99.75mg/kg.从空间分布特征来看,南京市土壤重金属元素Zn、Cu、Cd和Pb在工业区含量较高,Zn、Cu及Pb在老城区存在高值;Ni、Cr在工业区含量普遍较高,在老城区含量整体较低;Mn分布趋势较平缓,且与其他6种重金属元素分布特征明显不同.结合主成分分析与聚类分析结果可知,南京市土壤中Zn、Cu、Cd、Pb主要受工业和交通活动的影响,Ni和Cr主要受工业活动影响,Mn主要为自然来源.工业与交通活动是造成长三角地区工业城市土壤重金属污染的重要原因,同时也是长三角地区土壤重金属污染治理的重要方向. 展开更多
关键词 城市表土 土壤重金属 空间分布 物源解析 长三角地区 南京市
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张掖盆地1990s表土层深部土壤重金属分布特征及其来源分析
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作者 何甘地 何进忠 +1 位作者 牛洪斌 张忠平 《物探与化探》 CAS 2024年第5期1388-1399,共12页
甘肃省张掖盆地是国家现代农业示范区,也是1990s迄今唯一农业土壤调查与区域地球化学勘查相重合的地区。笔者搜集了1990s甘肃省物探队与化探队在张掖盆地及其周围山地采集的岩石、表土层深部土壤和水系沉积物的地球化学调查数据,按照拉... 甘肃省张掖盆地是国家现代农业示范区,也是1990s迄今唯一农业土壤调查与区域地球化学勘查相重合的地区。笔者搜集了1990s甘肃省物探队与化探队在张掖盆地及其周围山地采集的岩石、表土层深部土壤和水系沉积物的地球化学调查数据,按照拉依达法则和采样介质计算了元素在各个地质单元中的背景值;进而以重金属为主线,采用将区域表土层深部土壤背景值与中国土壤背景值和同时期耕作层土壤平均值作对比、第四系地层土壤背景值与区域土壤背景值作对比,以及将地球化学混合模型与地理学要素相结合的方法,探讨1990s张掖盆地表土层深部土壤重金属分布特征及其物质来源。相对中国土壤元素背景值,研究区表土层深部土壤富集Cu和Cd,贫Zn;与同时期耕作层土壤相比,Cr显著富集,Cu、Zn、Pb和As显著贫化。重金属Zn、Cd和As主要源于北祁连;Pb来源于龙首山;Hg和Cr可能主要与人类活动有关;表土层深部土壤中的H3潜在生态风险指数异常是西北风和东南风共同作用的结果。重金属在表土层深部土壤中的富集程度与人类活动强度正相关,与新构造运动强度负相关。本次研究为探讨该区区域土壤环境演化提供了科学数据。 展开更多
关键词 土壤 表土层深部土壤 重金属 物质来源 张掖盆地 甘肃
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