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Prediction of Apple Fruit Quality by Soil Nutrient Content and Artificial Neural Network
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作者 Mengyao Yan Xianqi Zeng +5 位作者 Banghui Zhang Hui Zhang Di Tan Binghua Cai Shenchun Qu Sanhong Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期193-208,共16页
The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu... The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu Province.Soil mineral elements and fruit quality were measured.The effect of soil nutrient content on fruit quality was analyzed by artificial neural network(ANN)model.The results showed that the prediction accuracy was highest(R2=0.851,0.847,0.885,0.678 and 0.746)in mass per fruit(MPF),hardness(HB),soluble solids concentrations(SSC),titratable acid concentration(TA)and solid-acid ratio(SSC/TA),respectively.The sensitivity analysis of the prediction model showed that soil available P,K,Ca and Mg contents had the greatest impact on the quality of apple fruit.Response surface method(RSM)was performed to determine the optimum range of the available P,K,Ca,and Mg contents in orchards In Feng County,which were 10∼20 mg⋅kg^(−1),170∼200 mg⋅kg^(−1),1000∼1500 mg⋅kg^(−1),and 80∼200 mg⋅kg^(−1),respectively.The research also concluded that improving the content of available P and available Ca in orchard soil was crucial to improve apple fruit quality in Feng County,Jiangsu Province. 展开更多
关键词 APPLE soil nutrients fruit quality artificial neural network sensitivity analysis response surface methodology analysis
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Knowledge Map of Soil Nutrient Migration Analysis Based on WOS (Web of Science) Database
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作者 Jiafeng Wang Jingsheng Chen +2 位作者 Qiuliang Cai Jinsheng Huang Liuqiang Zhou 《Agricultural Sciences》 CAS 2023年第3期398-421,共24页
It is important to understand the research trends and hotspots of global soil nutrient migration and control. Based on the core collection of WOS (Web of Science), citespace knowledge map analysis tool was used to ana... It is important to understand the research trends and hotspots of global soil nutrient migration and control. Based on the core collection of WOS (Web of Science), citespace knowledge map analysis tool was used to analyze the number of publications, cooperation networks, disciplines, research hotspots and frontier trends on nutrient migration in soil. The results showed that: the number of publications on the study of soil nutrient migration showed a good growth from 1990 to 2021. 173 countries had cooperative relationships. The number of articles published in the United States and China was significantly higher than that in other countries, while Chinese Academy of Sciences was the institution with the largest number of publications. It was a comprehensive system that permeates with agriculture, environmental science, botany and other disciplines. The research of nutrient migration in soil mainly focused on the measures of microbial community in different land types to promote nutrient transformation, improve soil fertility and reduce nutrient loss. In the future, the research trends will be the management measures of soil nutrient loss, the relationship between the change of soil nutrient and plant community diversity, and the remediation of agricultural contaminated soil. Through the above analysis, there was an overall understanding of soil nutrient migration. The research on nutrient migration may continue to increase in the future. It is suggested that Chinese research institutions, teams and universities need to strengthen international cooperation, and speed up their integration with the international community. 展开更多
关键词 CiteSpace soil nutrients Visual Analysis Research Progress nutrient Migration
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Nutrient coordination mechanism of tiger nut induced by rhizosphere soil nutrient variation in an arid area, China
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作者 TAN Jin WU Xiuqin +2 位作者 LI Yaning SHI Jieyu LI Xu 《Journal of Arid Land》 SCIE CSCD 2023年第10期1216-1230,共15页
Tiger nut is a bioenergy crop planted in arid areas of northern China to supply oil and adjust the planting structure.However,in the western region of Inner Mongolia Autonomous Region,China,less water resources have r... Tiger nut is a bioenergy crop planted in arid areas of northern China to supply oil and adjust the planting structure.However,in the western region of Inner Mongolia Autonomous Region,China,less water resources have resulted in a scarcity of available farmland,which has posed a huge obstacle to planting tiger nut.Cultivation of tiger nut on marginal land can effectively solve this problem.To fully unlock the production potential of tiger nut on marginal land,it is crucial for managers to have comprehensive information on the adaptive mechanism and nutrient requirement of tiger nut in different growth periods.This study aims to explore these key information from the perspective of nutrient coordination strategy of tiger nut in different growth periods and their relationship with rhizosphere soil nutrients.Three fertilization treatments including no fertilization(N:P(nitrogen:phosphorous)=0:0),traditional fertilization(N:P=15:15),and additional N fertilizer(N:P=60:15)were implemented on marginal land in the Dengkou County.Plant and soil samples were collected in three growth periods,including stolon tillering period,tuber expanding period,and tuber mature period.Under no fertilization,there was a significant correlation between N and P contents of tiger nut roots and tubers and the same nutrients in the rhizosphere soil(P<0.05).Carbon(C),N,and P contents of roots were significantly higher than those of leaves(P<0.05),and the C:N ratio of all organs was higher than those under other treatments before tuber maturity(P<0.05).Under traditional fertilization,there was a significant impact on the P content of tiger nut tubers(P<0.05).Under additional N fertilizer,the accumulation rate of N and P was faster in stolons than in tubers(P<0.05)with lower N:P ratio in stolons during the tuber expansion period(P<0.05),but higher N:P ratio in tubers(P<0.05).The limited availability of nutrients in the rhizosphere soil prompts tiger nut to increase the C:N ratio,improving N utilization efficiency,and maintaining N:P ratio in tubers.Elevated N levels in the rhizosphere soil decrease the C:N ratio of tiger nut organs and N:P ratio in stolons,promoting rapid stolon growth and shoot production.Supplementary P is necessary during tuber expansion,while a higher proportion of N in fertilizers is crucial for the aboveground biomass production of tiger nut. 展开更多
关键词 tiger nut STOICHIOMETRY rhizosphere soil nitrogen addition marginal land
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Climate Variability and Soil Nutrients Status along Altitudinal Gradient in Kigezi Highlands, Southwestern Uganda 被引量:2
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作者 Fortunate Twagiramaria Casim Umba Tolo 《Natural Resources》 2016年第1期1-22,共22页
Kigezi highlands currently experiences changes in precipitation and temperature which modify the evaporation and soil moisture storage leading to alterations in runoff and other components of hydrological systems. Ext... Kigezi highlands currently experiences changes in precipitation and temperature which modify the evaporation and soil moisture storage leading to alterations in runoff and other components of hydrological systems. Extreme events, like floods and droughts, are more intense and frequent. Furthermore heavy unpredictable rainfall has become frequent in the area, causing soil erosion and floods that destroy crops. Soil erosion is particularly a pressing challenge due to steep-sided hills leading to deterioration of soil nutrients including soil fertility. The unpredictable rains and droughts are attributed to climate change and variability. Consequently, climate change and variability have caused a significant impact on soil nutrients which have affected the agricultural productivity in the area. This paper presents findings of empirical study which explored the climate variability and soil nutrient status along altitudinal gradient. The paper particularly addresses key questions of: land management practices in the study area, nutrient availability and their effects on productivity of selected crops along altitudinal gradient in changing climate and variability. Independent variables such as topographic sequence along altitudinal gradient were evaluated against dependent variables such as yield harvests of selected grown crops and soil nutrients. Samples for crop yields were collected along transect of 0.5 kilometer using a quadrant of 4 × 4 m<sup>2</sup> along attitudinal gradient. Soil samples were taken from selected plots at 0-20cm soil depth for nutrient analysis. Analysis of physical and chemical soil parameters was carried out on soil samples and these include: soil pH, soil organic content, total nitrogen, available soil phosphorous and exchangeable bases (Ca, Mg, K and Na). The study showed that middle parts of the transects had the highest concentration of most soil nutrients, probably because the middle parts could have been a deposition centre for some organic matter from the upper parts of the hills, and lower lying areas were being affected by floods that affects the decomposition of organic matter which is the main source of nutrients. Similarly, the middle parts of the study were the most fertile due to the high concentration of soil nutrient compositions. This indicates that crop yields were significantly affected by availability of soil nutrients along same gradient, attributable to the severity in soil erosion, nutrients leaching and farming practices. 展开更多
关键词 Climate Change Climate Variability soil nutrients Kigezi Highlands Altitudinal Gradient Southwestern Uganda
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Fire alters the availability of soil nutrients and accelerates growth of Eucalyptus grandis in Zambia
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作者 Donald Chungu Phillimon Ng’andwe +1 位作者 Henry Mubanga Felix Chileshe 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1637-1645,共9页
Fire has been used to prepare land during tree plantation establishment for many years but uncertainty about how ecosystems respond to prescribed burning makes it difficult to predict the effects of fire on soil nutri... Fire has been used to prepare land during tree plantation establishment for many years but uncertainty about how ecosystems respond to prescribed burning makes it difficult to predict the effects of fire on soil nutrients.The aim of this study was to determine the effect of burning accumulated forest residues(slash)on soil chemical properties and how trees respond.We analyzed 40 burned and unburned sites and compared growth of Eucalyptus grandis W.Hill ex Maiden between sites.Soil pH increased by 39%after fire,suggesting reduced soil acidity and increased liming.Total nitrogen increased by 100%;other nutrients(Ca^2+,Mg^2+and K^+)also increased.Increase in nutrients had a significant effect on the growth of E.grandis;larger and taller trees were associated more with burned than unburned sites.This study provides evidence that burning accumulated slash during land preparation prior to plantation establishment alters soil nutrient status and enhances the growth of E.grandis. 展开更多
关键词 Nitrogen mineralization Forest residue burning soil nutrients Zambia exotic plantations Plantation establishment Eucalyptus grandis
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Changes in morphology and soil nutrient patterns of nebkhas in arid regions along a precipitation gradient
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作者 WeiCheng Luo WenZhi Zhao +1 位作者 Bing Liu Heng Ren 《Research in Cold and Arid Regions》 CSCD 2021年第3期256-267,共12页
Nebkhas, discrete mounds of sand and vegetation, are a common landscape feature critical to the stability of desert ecosystems and supported by limited precipitation. Nebkha morphology and spatial pattern vary in land... Nebkhas, discrete mounds of sand and vegetation, are a common landscape feature critical to the stability of desert ecosystems and supported by limited precipitation. Nebkha morphology and spatial pattern vary in landscapes, but it is unclear how they change along precipitation gradients in arid and semi-arid regions. In this study we determined morphology and soil nutrient patterns of nebkha from different regions of northwestern China. The objective of this study was to understand zonal differences among nebkhas and how morphological characteristics and soil nutrient patterns of nebkha change along a precipitation gradient in northwestern China. Our results shows that mean annual precipitation(MAP) had significant effects on morphological characteristics of nebkhas such as height, area, and volume which significantly decreased with an increase in MAP. MAP had significant positive effects on shrub cover and species richness of nebkha. Soil nutrients such as soil organic matter(SOM), total carbon(TC), total nitrogen(TN), and total phosphorus(TP) in the 0-10 cm layer increased with an increase of MAP, and soil nutrient content within nebkhas was higher than in inter-nebkha areas.We concluded that nebkhas are "fertile islands" with an important role in ecosystem dynamics in study regions. Further,MAP is a key factor which determined zonal differences, morphological, and soil nutrients patterns of nebkhas. However,disturbance, such as animal grazing, and planted sand-stabilizing vegetation accelerated the degeneration of nebkha landscapes. We recommend implementation of protective measures for nebkhas in arid and semi-arid areas of China. 展开更多
关键词 Nebkha MORPHOLOGY soil nutrient precipitation gradient arid and semi-arid lands
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Differences of Soil Nutrient Contents under Different Land Use Patterns in Niyang River Basin
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作者 Heping MA Zhu DONG 《Agricultural Biotechnology》 CAS 2022年第2期80-84,共5页
[Objectives]This study was conducted to investigate the variation characteristics of soil nutrient contents under different land use patterns in the middle and upper reaches of the Niyang River in Tibet.[Methods]With ... [Objectives]This study was conducted to investigate the variation characteristics of soil nutrient contents under different land use patterns in the middle and upper reaches of the Niyang River in Tibet.[Methods]With the cultivated land,grass land and forest land in the middle and upper reaches of the Niyang River as the research objects,216 soil samples were collected in layers(0-10,10-20,20-30 cm)by the standard sampling method,and the soil total nitrogen,alkali-hydrolyzable nitrogen,total potassium,available potassium,total phosphorus,available phosphorus and organic matter were determined.[Results]The contents of soil organic matter,total nitrogen and alkali-hydrolyzable nitrogen in the middle and upper reaches of Niyang River in Tibet ranked as forest land>grass land>cultivated land,and there were significant differences between the three(P<0.05).The total potassium contents of grass land and forest land were not much different,and the contents of available potassium exhibited an order of forest land>grass land>cultivated land.The distribution of soil total nutrients and available nutrients under different land use patterns showed a certain degree of surface aggregation.The contents of total nutrients and available nutrients in the soil at the 0-10 cm depth were significantly higher than those at 10-20 and 20-30 cm,and there were significant differences between the three(P<0.05).The average content of alkali-hydrolyzable nitrogen was the largest in forest soil and the smallest in cultivated land under the three land use patterns in the study area.The average content of soil available phosphorus in cultivated land(19.47 mg/kg)was significantly higher than those in grass land(5.73 mg/kg)and forest land(5.19 mg/kg).The above results indicate that long-term vegetation restoration can improve the soil quality of the middle and upper reaches of the Niyang River.[Conclusions]The results of this study research provide basic support for improving the soil effect in the area. 展开更多
关键词 soil nutrient Land use type soil quality Available nutrient TIBET
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The Characteristics of Soil Nutrients in Terracing Land under Different Land Use Patterns in Three Gorges Reservoir Area
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作者 Guojian CHEN Chunli LI +3 位作者 Juanjuan LI Liangyu LIAO Jie WEI Peixia LI 《Asian Agricultural Research》 2017年第3期89-92,共4页
In this study,taking the typical terracing land in Wushan County of Chongqing Municipality for example,we study the distribution of soil nutrients in the terracing land under different land use patterns in Three Gorge... In this study,taking the typical terracing land in Wushan County of Chongqing Municipality for example,we study the distribution of soil nutrients in the terracing land under different land use patterns in Three Gorges Reservoir Area. We conduct field survey and sampling on three different land use patterns( cash crop land,food crop land and abandoned land),and do the indoor experimental analysis of soil nutrient indicators. The results indicate that there is significant or very significant impact on soil nutrients under different land use patterns. The content of soil organic matter declines in sequence from abandoned land,food crop land to cash crop land; the content of soil N declines in sequence from cash crop land,abandoned land to food crop land; the content of soil P declines in sequence from cash crop land,food crop land to abandoned land; the content of soil K declines in sequence from abandoned land,cash crop land to food crop land. The result is in close relation to land use patterns,human cultivation activity,land disturbance and application of fertilizer. 展开更多
关键词 Three Gorges Reservoir Area Terracing land Land use patterns soil nutrients
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Fertilization Status and Soil Nutrient Condition in Some Asparagus Production Regions of Zhejiang Province
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作者 Haimin KONG Yiding CHEN +2 位作者 Yugen JIANG Jianqiang LI Jianqing PAN 《Asian Agricultural Research》 2017年第12期47-51,共5页
Asparagus is delicious,with rich nutrition,and it is one of main economic crops in Zhejiang Province.In this paper,by investigating fertilization situations of farmers in several asparagus production regions(Fuyang,Pi... Asparagus is delicious,with rich nutrition,and it is one of main economic crops in Zhejiang Province.In this paper,by investigating fertilization situations of farmers in several asparagus production regions(Fuyang,Pinghu,Changxing and Cixi) and soil nutrient condition of asparagus garden with different plantation years,fertilization status and nutrient condition of asparagus garden were described,and fertilization suggestion was proposed,which aimed to guide scientific fertilization of asparagus and promote healthy development of industry. 展开更多
关键词 ASPARAGUS FERTILIZATION soil nutrient
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Effects of Long-term Return of Milk Vetch(Astragalus sinicus)on Soil Nutrients and Microorganism Communities in Double-rice Cropping Field
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作者 Rong HU Kaiwei CHEN +3 位作者 Kailun SONG Xing YIN Chunhuo ZHOU Guorong NI 《Agricultural Biotechnology》 CAS 2021年第4期127-129,133,共4页
[Objectives]This study was conducted to investigate the effects of milk vetch(Astragalus sinicus)on soil nutrients and microorganisms in paddy fields after returning to the field.[Methods]Three treatments,no fertiliza... [Objectives]This study was conducted to investigate the effects of milk vetch(Astragalus sinicus)on soil nutrients and microorganisms in paddy fields after returning to the field.[Methods]Three treatments,no fertilization,single application of chemical fertilizers and milk vetch return combined with chemical fertilizers,were set up to determine soil nutrient contents and the quantity of microorganisms,respectively.[Results]The return of milk vetch combined with chemical fertilizers could significantly increase the contents of organic matter and total nitrogen in the paddy soil,while the contents of available potassium and available phosphorus decreased.Milk vetch return combined with chemical fertilizers could significantly increase the quantity of soil microorganisms in the paddy field.[Conclusions]The return of milk vetch can be used as a feasible measure to improve soil fertility. 展开更多
关键词 Milk vetch Returning to field soil nutrient MICROORGANISMS
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Effects of Raising Chickens Under Moringa oleifera Forests on Soil Nutrients and Selenium Absorption by M. oleifera
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作者 Liping PAN Hanyu ZHU +3 位作者 Ying XING Guoxin SHA Jinping CHEN Yongxian LIU 《Agricultural Biotechnology》 CAS 2021年第6期10-13,共4页
[Objectives]This study was conducted to investigate the effects of raising chickens under Moringa oleifera forests on soil nutrient changes and selenium absorption by M.oleifera.[Methods]The nutrient contents of the s... [Objectives]This study was conducted to investigate the effects of raising chickens under Moringa oleifera forests on soil nutrient changes and selenium absorption by M.oleifera.[Methods]The nutrient contents of the soil and the selenium contents of different parts of M.oleifera were determined and analyzed.[Results]Raising chickens under the investigated M.oleifera forest improved the soil.Compared with the control,the soil organic matter,hydrolyzable nitrogen,available phosphorus,and available potassium of the plots for underforest chicken raising were significantly improved;the changes were the most significant within the range of 2 m from the chicken houses,respectively,and the values were 1.39,1.38,1.52 and 1.31 times of the control,respectively;soil bulk density decreased,total porosity increased,soil structure and permeability improved,and soil pH values at 2 and 5 m away from the chicken houses were significantly higher than the control by 0.34 and 0.28 unit,respectively;and raising chickens under the forest promoted the absorption and utilization of selenium in M.oleifera,and the selenium contents in stems and leaves of M.oleifera were 1.64 times and 1.51 times of the control,respectively.[Conclusions]This study provides a theoretical basis for the high-value selenium-enriching compound economic model of raising chickens under M.oleifera forests. 展开更多
关键词 Moringa oleifera Raising chickens under forests soil nutrients SELENIUM
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Changes in Soil Nutrients of Farmland with Different Cultivation Years of Panax ginseng
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作者 Changming GE Xin WANG +3 位作者 Aixuan WU Yun LU Hongyan ZHAO Renzhe PIAO 《Asian Agricultural Research》 2017年第12期75-78,共4页
Through analyzing the soil organic matters(N,P,K) of farmland cultivated with different years of Panax ginseng,this paper studied the changes in soil nutrients of farmland with different vertical depths and cultivatio... Through analyzing the soil organic matters(N,P,K) of farmland cultivated with different years of Panax ginseng,this paper studied the changes in soil nutrients of farmland with different vertical depths and cultivation years of P.ginseng.Results indicated that the vertical structure was obvious in soil nutrients of farmland with different cultivation years of P.ginseng;in most cases,the soil nutrient content gradually declined with the fibrous roots of P.ginseng spreading downward;the soil electrical conductivity(EC),total nitrogen(TN),total phosphorus(TP),total potassium(TK),available nitrogen,available phosphorus were manifested as surface layer > root layer > bottom layer,while the available potassium was manifested as surface soil and bottom layer > root layer;the soil pH changed in the range of 5.69-6.22,suitable for growth of P.ginseng.It is expected to provide theoretical basis for improvement of soil nutrients of farmland with cultivation of P.ginseng. 展开更多
关键词 Farmland with cultivation of Panax ginseng soil nutrients Cultivation years
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A Study of Soil Nutrients in the Terrace Field Changed from Mountain Slope in Three Gorges Reservoir Region
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作者 Guojian CHEN Chunjuan LI +3 位作者 Chunli LI Juanjuan LI Jie WEI Hongwei DONG 《Asian Agricultural Research》 2016年第8期77-80,共4页
In order to accurately grasp the soil fertility in Three Gorges Reservoir Region after changing mountain slope into terrace field,we take Wushan County for example,and use the spatio-temporal substitution method to an... In order to accurately grasp the soil fertility in Three Gorges Reservoir Region after changing mountain slope into terrace field,we take Wushan County for example,and use the spatio-temporal substitution method to analyze the soil nutrient status and trend about the terrace field changed from mountain slope under different length of implementation.The results show that the soil fertility is generally low in the study area,and according to the soil nutrient grading standards in the second national land survey,the average content of total nitrogen,available potassium,organic matter and available phosphorus reaches Standard III,Standard III,Standard IV and Standard V,respectively,and the spatial heterogeneity of soil nutrients is small.Compared to the sloping land,the terrace field changed from mountain slope has increasing soil nutrients on the whole with the length of farming.The mean of various indicators about soil nutrients in the terrace field changed from mountain slope for 2 years is lower than in the sloping land,and there is the biggest difference in soil fertility,while the mean of various indicators about soil nutrients in the terrace field changed from mountain slope for 14 years shows a linear upward trend,and the difference in soil fertility decreases. 展开更多
关键词 Changing mountain slope into terrace field soil nutrients Three Gorges Reservoir Region
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Research on Influencing Factors of Spatial Variation of Soil Nutrients
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作者 Tingting MENG 《Meteorological and Environmental Research》 CAS 2020年第4期95-97,共3页
Based on previous studies,the research methods and influencing factors of spatial variation of soil nutrients are summarized.It is concluded that the spatial variation of soil nutrients is studied generally by geostat... Based on previous studies,the research methods and influencing factors of spatial variation of soil nutrients are summarized.It is concluded that the spatial variation of soil nutrients is studied generally by geostatistics methods,and the spatial distribution of nutrients is visually observed by using Kriging interpolation method.The influencing factors mainly include topography,sampling method,sampling spacing,sampling density and sampling scale.The influence of random sampling and grid sampling on interpolation is analyzed based on the specific conditions of the actual study area.The influence of sampling density and topography on the spatial variation of soil nutrients cannot be ignored,especially on available nutrients.When samples are collected in a large area(under a small and medium scale),the spatial variation of soil nutrients is large,and they have strong spatial autocorrelation;in a small area(namely under a large scale),the spatial variability of soil nutrients is small,and they have obvious spatial autocorrelation.This study can provide intuitive and convenient reference materials for the following researchers. 展开更多
关键词 soil nutrients Spatial variation GEOSTATISTICS Sampling method Sampling scale Sampling density
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Evaluation of Soil Nutrient Content and Fertility in Main Dry Farming Regions of Laos
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作者 Shuyi LIU Yuyi HUANG +7 位作者 Guifen CHEN Yancheng MENG Bin LIU Zhong LIU Yanfei HUANG Liping XIE Qizhan TANG Moryang CHUAYENG 《Asian Agricultural Research》 2022年第3期25-29,32,共6页
[Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil s... [Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil samples in the 0-20 cm layer of the main dryland in southern and northern provinces of Laos.Soil pH,organic matter,total nitrogen,available nitrogen,available phosphorus,available potassium,exchangeable calcium,exchangeable magnesium and available zinc content were analyzed.[Results]The soil in the main dry farming regions of Laos was acidic,the overall fertility level was good,and the exchangeable calcium and magnesium contents were low.There were differences in soil nutrient content in the dry farming regions of southern and northern Laos.Drylands where cassava and maize were growed had higher fertility.[Conclusions]It is suggested to apply lime or alkaline fertilizer in the dry land with acid soil to increase soil pH and increase the supply of soil calcium and magnesium.Organic fertilizer should be applied to improve soil water retention capacity,and it is necessary to pay attention to the fertilization ratio of macroelements to balance fertilization. 展开更多
关键词 Dry land soil nutrient content Fertility evaluation Laos
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Wet and Dry Season Effects on Select Soil Nutrient Contents of Upland Farms in North Bank Region of the Gambia
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作者 Ebrima Sonko Daniel N. Tsado +2 位作者 Sidat Yaffa Appollonia A. Okhimamhe Julia Eichie 《Open Journal of Soil Science》 2016年第3期45-51,共7页
The study was conducted in three villages of North Bank Region of the Gambia in 2013 and 2014. We examined wet and dry season effects on select soil nutrient contents of upland farms in North Bank Region of the Gambia... The study was conducted in three villages of North Bank Region of the Gambia in 2013 and 2014. We examined wet and dry season effects on select soil nutrient contents of upland farms in North Bank Region of the Gambia. The objective was to evaluate changes in soil nutrient contents in both wet and dry seasons. Soil samples were collected from three RCBD upland fields with three replications at a depth of 0 - 15 cm and analyzed for pH, Soil Organic Carbon (SOC), and soil moisture content. The gravimetric method of moisture estimation was used. The results showed that soil moisture content, soil TN, and soil pH are significantly different (P < 0.05) during the two seasons. There was no significant difference in SOC between the two seasons in the study area. The study concluded that soil nutrients were more readily available during the wet season than during the dry season probably because there is more soil moisture available in the wet season that facilitates soil nutrient release. The study concludes that soil moisture has to be available in order for some select soil nutrients to be released for plant uptake. 展开更多
关键词 soil nutrients Wet Season Dry Season pH
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Nutrient Budget and Soil Nutrient Status in Greenhouse System 被引量:29
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作者 YU Hai-ying LI Ting-xuan ZHANG Xi-zhou 《Agricultural Sciences in China》 CSCD 2010年第6期871-879,共9页
This paper is based on nutrient budget and its effects on soil nutrient status in typical greenhouse system in China to provide a basis for raising the utilization rate of fertilizers and maintaining the sustainable d... This paper is based on nutrient budget and its effects on soil nutrient status in typical greenhouse system in China to provide a basis for raising the utilization rate of fertilizers and maintaining the sustainable development of agriculture in the greenhouse.By investigating the management of 18 representative greenhouses in Shouguang,Shandong Province,China,and analyzing both the greenhouse and open field soil samples,the soil nutrient budget and the trend of nutrient accumulation and translocation in soils were thus studied.The results under greenhouse system showed that the average annual inputs of N,P2O5 and K2O were 4 088,3 655 and 3 437 kg ha-1,respectively.The total inputs of N,P2O5 and K2O provided by chemical fertilizers which are the main source of soil nutrient were 63,61 and 66%,respectively.The utilization rates of N,P2O5 and K2O were only 24,8,46% and the input ratio among N,P2O5 and K2O (1:0.9:0.8) was quite different from the uptake ratio (1:0.3:1.4).It had caused the excess of N,P2O5 and K2O in the soil,and the theoretical surpluses were 3 214,3 401 and 2 322 kg ha-1,respectively,for N,P2O5 and K2O.The level of the organic matter,total nitrogen,nitrate nitrogen,available phosphorus,and available potassium was increased substantially,and their maximum level was observed in the topsoil (0-20 cm) with an average value being 1.4,1.9,21.2,5.4,and 3.7 times higher than that of the open field soil,respectively.The greenhouse soils showed leaching of the nutrients,especially NO3- which would cause a potential risk to the quality of groundwater in the area.It is necessary to apply more organic manure and provide nutrients according to the crop requirements and soil fertility as it could not only produce high crop yield,but also be beneficial to balance the soil nutrient and improve the utilization rate of fertilizers.Further,there would be no significant surplus of nutrients which may leach out of soil to contaminate the environment. 展开更多
关键词 土壤养分收支 温室系统 养分状况 预算 肥料利用率 P2O5 硝酸盐氮 平均价值
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Effect of Different Vegetation Systems on Soil Erosion and Soil Nutrients in Red Soil Region of Southeastern China 被引量:57
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作者 S. KUMAR 《Pedosphere》 SCIE CAS CSCD 2003年第2期121-128,共8页
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 south... 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 covers.However, they were still much lower than expected, thus these biological measurements are still needed to be carried out continuously. 展开更多
关键词 土壤侵蚀 土壤肥力 红壤 植被系统 中国 东南地区 细菌数量
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The Heterogeneity and Its Influencing Factors of Soil Nutrients in Peak-Cluster Depression Areas of Karst Region 被引量:21
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作者 ZHANG Wei CHEN Hong-song +3 位作者 WANG Ke-lin SU Yi-rong ZHANG Ji-guang YI Ai-jun 《Agricultural Sciences in China》 CAS CSCD 2007年第3期322-329,共8页
By selecting a typical peak-cluster depression area of karst region in Southwest China, we evaluated the effect of land use types and topographic factors on soil nutrients. Grid and line sampling methods were used to ... By selecting a typical peak-cluster depression area of karst region in Southwest China, we evaluated the effect of land use types and topographic factors on soil nutrients. Grid and line sampling methods were used to sample soil in depression and slope lands respectively, and classical statistical tools were applied to analyze the spatial variability character of soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), available potassium (AK), pH, and C/N. It was found that land use type was the dominant factor that effected the spatial heterogeneity of SOC, TN, TP, TK, AN, and AP. The content of SOC, TN, and AN decreased with the increase of land use intensity. Due to high fertilizer input, TP and AP in tillage fields were higher than those in the other land use types. TK had no obvious change trend among various land use types. Topographic factors had a significant effect on SOC, TN, TP, AN, AP, AK, and pH. Habitat factor was the dominant factor that effected AK. Altitude factor was the dominant factor for pH. However, all of these factors had no significant effect on C/N. Tillage practice had important effect on soil nutrients loss and soil degradation in the fragile karst ecosystem, and the input of organic manure should be increased in this region. 展开更多
关键词 土壤营养 不均匀性 影响因子 岩溶地区
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Effects of artificially cultivated biological soil crusts on soil nutrients and biological activities in the Loess Plateau 被引量:7
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作者 YanMin ZHAO QingKe ZHU +4 位作者 Ping LI LeiLei ZHAO LuLu WANG XueLiang ZHENG Huan MA 《Journal of Arid Land》 SCIE CSCD 2014年第6期742-752,共11页
Biological soil crusts(BSCs) play an important role in the early succession of vegetation restoration in the Loess Plateau, China. To evaluate the effects of artificially cultivated BSCs on the soil surface micro-envi... Biological soil crusts(BSCs) play an important role in the early succession of vegetation restoration in the Loess Plateau, China. To evaluate the effects of artificially cultivated BSCs on the soil surface micro-environment, we obtained natural moss crusts and moss-lichen crusts from the Loess Plateau of Shaanxi province, and subsequently inoculated and cultivated on horizontal and sloping surfaces of loess soil in a greenhouse. The chemical and biological properties of the subsoil under cultivated BSCs were determined after 10 weeks of cultivation. The results indicated that BSCs coverage was more than 65% after 10 weeks of cultivation. Moss crust coverage reached 40% after 5 weeks of cultivation. Compared with the control, soil organic matter and available nitrogen contents in moss crust with the horizontal treatments increased by 100.87% and 48.23%, respectively; increased by 67.56% and 52.17% with the sloping treatments, respectively; they also increased in moss-lichen crust with horizontal and sloping treatments, but there was no significant difference. Available phosphorus in cultivated BSCs was reduced, soil pH was lower and cationic exchange capacity was higher in cultivated BSCs than in the control. Alkaline phosphatase, urease and invertase activities were increased in artificially cultivated BSCs, and alkaline phosphatase activity in all cultivated BSCs was obviously higher than that in the control. Numbers of soil bacteria, fungi and actinomycetes were increased in the formation process of cultivated BSCs. These results indicate that BSCs could be formed rapidly in short-term cultivation and improve the micro-environment of soil surface, which provides a scientific reference for vegetation restoration and ecological reconstruction in the Loess Plateau, China. 展开更多
关键词 生物土壤结皮 人工栽培 黄土高原 生物活性 土壤养分 碱性磷酸酶活性 阳离子交换容量 基站控制器
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