检索结果-南通市图书馆

Response of soil respiration to short-term changes in precipitation and nitrogen addition in a desert steppe

Journal of Arid Land 2023年第9期15卷 1084-1106页

作者： MA Jinpeng PANG Danbo HE Wenqiang ZHANG Yaqi WU Mengyao LI Xuebin CHEN Lin College of Forestry and Prataculture Ningxia UniversityYinchuan 750021China College of ecological Environment Ningxia UniversityYinchuan 750021China Breeding Base for State key laboratory of Land Degradation and ecological restoration in Northwest China Ningxia UniversityYinchuan 750021China

Changes in precipitation and nitrogen(N)addition may significantly affect the processes of soil carbon(C)cycle in terrestrial ecosystems,such as soil ***,relatively few studies have investigated the effects of changes in precipitation and N addition on soil respiration in the upper soil layer in desert *** this study,we conducted a control experiment that involved a field simulation from July 2020 to December 2021 in a desert steppe in Yanchi County,***,we measured soil parameters including soil temperature,soil moisture,total nitrogen(TN),soil organic carbon(SOC),soil microbial biomass carbon(SMBC),soil microbial biomass nitrogen(SMBN),and contents of soil microorganisms including bacteria,fungi,actinomyces,and protozoa,and determined the components of soil respiration including soil respiration with litter(RS+L),soil respiration without litter(RS),and litter respiration(RL)under short-term changes in precipitation(control,increased precipitation by 30%,and decreased precipitation by 30%)and N addition(0.0 and 10.0 g/(m^(2)·a))*** results indicated that short-term changes in precipitation and N addition had substantial positive effects on the contents of TN,SOC,and SMBC,as well as the contents of soil actinomyces and *** addition,N addition significantly enhanced the rates of RS+L and RS by 4.8%and 8.0%(P0.05).The mean RL/RS+L value observed under all treatments was 27.63%,which suggested that RL is an important component of soil respiration in the desert steppe *** results also showed that short-term changes in precipitation and N add

关键词： soil respiration litter respiration nitrogen deposition soil carbon soil microorganisms climate change desert steppe ecosystems

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Inorganic Phosphorus Fractions and Phosphorus Availability in a Calcareous soil Receiving 21-Year Superphosphate Application

引用

Pedosphere 2010年第3期20卷 304-310页

作者： WANG Jun LIU Wen-Zhao MU Han-Feng DANG Ting-Hui State key laboratory of soil erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conser-vation Northwest A&F University Yangling 712100 (China) College of Urban and Environment Northwest University Xi'an 710127 (China)

A long-term （21-year） field experiment was performed to study the responses of soil inorganic P fractions and P availability to annual fertilizer P application in a calcareous soil on the Loess Plateau of China. soil Olsen-P contents increased by 3.7, 5.2, 11.2 and 20.6 mg P kg-1 after 21-year annual fertilizer P application at 20, 39, 59, and 79 kg P ha-1, respectively. Long-term fertilizer P addition also increased soil total P and inorganic P （Pi） contents significantly. The contents of inorganic P fractions were in the order of Ca10-P 〉 Cas-P 〉 Fe-P 〉 A1-P 〉 occluded P 〉 Ca2-P in the soil receiving annual fertilizer P application. Fertilizer P application increased Cas-P, A1-P and Ca2-P contents as well as their percentages relative to Pi. Pi application increased Fe-P and occluded P contents but nor their percentages. soil Ca10- P content remained unchanged after fertilizer P application while its percentage relative to Pi declined with increasing fertilizer P rate. All Pi fractions but Ca10-P were correlated with Olsen-P significantly. 90% of variations in Olsen-P could be explained by Pi fractions, and the direct contribution of Cas-P was predominant. Long-term annual superphosphate application would facilitate the accumulation of soil Cas-P, and thus improve soil P availability.

关键词： long-term experiment Olsen-P path analysis Loess Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Infiltration characteristics of non-aqueous phase liquids in undisturbed loessal soil cores

引用

Journal of Environmental Sciences 2009年第10期21卷 1424-1431页

作者： WANG Yunqiang SHAO Ming'an State key laboratory of soil erosion and Dry-land Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Northwest A&F University Yangling 712100 China. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The widespread contamination of soils and aquifers by non-aqueous phase liquids （NAPL）, such as crude oil, poses serious environmental and health hazards globally. Understanding the infiltration characteristics of NAPL in soil is crucial in mitigating or remediating soil contamination. The infiltration characteristics of crude and diesel oils into undisturbed loessal soil cores, collected in polymethyl methacrylate cylindrical columns, were investigated under a constant fluid head （3 era） of either crude oil or diesel oil. The infiltration rate of both crude and diesel oils decreased exponentially as wetting depth increased with time. soil core size and bulk density both had significant effects on NAPL infiltration through the undisturbed soil cores; a smaller core size or a greater bulk density could reduce oil penetration to depth. Compacting soil in areas susceptible to oil spills may be an effective stratage to reduce contamination. The infiltration of NAPL into soil cores was spatially anisotropic and heterogeneous, thus recording the data at four points on the soil core is a good stratage to improve the accuracy of experimental results. Our results revealed that crude and diesel oils, rather than their components, have a practical value for remediation of contaminated loessal soils.

关键词： crude oil diesel oil soil compaction soil core sample size the Loess Plateau of China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Genomic analyses of metal resistance genes in three plant growth promoting bacteria of legume plants in Northwest mine tailings, China

引用

Journal of Environmental Sciences 2015年第1期27卷 179-187页

作者： Pin Xie Xiuli Hao Martin Herzberg Yantao Luo Dietrich H.Nies Gehong Wei State key laboratory of soil erosion and Dryland Farming on the Loess Plateau College of Life Science Northwest A&F University Molecular Microbiology Institute for Biochemistry and Biotechnology Martin-Luther-University Halle-Wittenberg

To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria（PGPB）. It shows that： Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF（Cation Diffusion Facilitator）, Hup E/Ure J and CHR（chromate ion transporter） family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative Cop A/Cue O system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while Znt A transporter, assisted with putative Czc D, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid（IAA） secretion,indicating a potential in-site phytoremediation usage in the mining tailing regions of China.

关键词： Plant growth promoting bacteria Metal resistance gene Legume–rhizobia symbiosis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Predicted Climate Change will Increase Landslide Risk in Hanjiang River Basin,China

引用

Journal of Earth Science 2024年第4期35卷 1334-1354页

作者： Xinggang Tang Lingjian Wang Huiyong Wang Yingdan Yuan Dou Huang Jinchi Zhang Co-Innovation Center for Sustainable Forestry in Southern China Jiangsu Province Key Laboratory of Soil and Water Conservation and Ecological RestorationNanjing Forestry UniversityNanjing210037China Jiangsu key laboratory of Crop Genetics and Physiology College of Horticulture and Plant ProtectionYangzhou UniversityYangzhou225009China College of Forestry Nanjing Forestry UniversityNanjing210037China

Landslides are widespread geomorphological phenomena with complex mechanisms that have caused extensive causalities and property damage *** scale and frequency of landslides are presently increasing owing to the warming effects of climate change,which further increases the associated safety *** this study,the relationship between historical landslides and environmental variables in the Hanjiang River Basin was determined and an optimized model was used to constrain the relative contribution of variables and best spatial response *** optimal MaxEnt model was used to predict the current distribution of landslides and influence of future rainfall changes on the landslide *** results indicate that environmental variables in the study area statistically correlate with landslide events over the past 20 *** MaxEnt model evaluation was applied to landslide hazards in the Hanjiang River Basin based on current climate change *** results indicate that 25.9%of the study area is classified as a high-risk *** main environmental variables that affect the distribution of landslides include altitude,slope,normalized difference vegetation index,annual precipitation,distance from rivers,and distance from roads,with a cumulative contribution rate of approximately 90%.The annual rainfall in the Hanjiang River Basin will continue to increase under future climate warming *** rainfall will further increase the extent of high-and medium-risk areas in the basin,especially when following the RCP8.5 climate prediction,which is expected to increase the high-risk area by 10.7%by ***,high landslide risk areas in the basin will migrate to high-altitude areas in the future,which poses new challenges for the prevention and control of landslide *** study demonstrates the usefulness of the MaxEnt model as a tool for landslide susceptibility prediction in the Hanjiang River Basin caused by global warming and yi

关键词： Hanjiang River Basin climate change environmental factor landslide susceptibility assessment MaxEnt model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

What is the mass of loess in the Loess Plateau of China?

引用

Science Bulletin 2019年第8期64卷 534-539页

作者： Yuanjun Zhu Xiaoxu Jia Jiangbo Qiao Ming'an Shao State key laboratory of soil erosion and Dryland Farming on the Loess Plateau Northwest A&F University Institute of soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources College of Resources and Environment University of Chinese Academy of Sciences key laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The Loess Plateau of China(LP) has the largest and thickest loess deposits in the world. Quantifying the amount of loess in the LP is crucial for investigating the accumulation and erosion of loess, and determining the regional soil and water resource capacity. We used loess thickness data, a pedotransfer function for bulk density(BD), and the clay content data observed in 242 sites across the LP to derive the BD of loess and then estimate the loess mass and its distribution across the LP. The results indicated that the average BD of loess between the surface and bedrock is 1.58 g cm^(-3), varying from 1.18 to 1.87 g cm^(-3).The total loess mass is approximately 5.45 ? 10^(13) t, and the average loess mass over an area of 1 m^2 is 169 t, ranging from 1.36 to 585 t. The greatest mass of loess is in the south-central of the LP while the lowest mass of loess is in the northwest and river valley areas. Our estimate of loess mass provides key data for calculating water, carbon, and nutrient storages in the LP, which improves our understanding of soil-water processes and ecohydrological systems in this landscape.

关键词： The Loess Plateau Loess mass Pedotransfer function soil erosion Bulk density

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Temporal and spatial variation characteristics of extreme precipitation on the Loess Plateau of China facing the precipitation process

引用

Journal of Arid Land 2023年第4期15卷 439-459页

作者： ZHANG Yixin LI Peng XU Guoce MIN Zhiqiang LI Qingshun LI Zhanbin WANG Bin CHEN Yiting State key laboratory of Eco-Hydraulic in Northwest Arid Region Xi'an University of TechnologyXi'an 710048China key laboratory of National Forestry and Grassland Administration on ecological Hydrology and Disaster Prevention in Arid Regions Northwest Survey and Planning Institute of National Forestry and Grassland AdministrationXi'an 710048China State key laboratory of soil erosion and Dryland Farming on the Loess Plateau Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China

The preceding and succeeding precipitation(PSP)often act together with extreme precipitation(EP),in turn,causing floods,which is an objective component that is often overlooked with regard to summer flood hazards in the arid region of Northwest *** this study,event-based extreme precipitation(EEP)was defined as continuous precipitation that includes at least one day of *** analyzed the spatiotemporal variation characteristics of four EEP types(front EEP,late EEP,balanced EEP,and single day EEP)across the Loess Plateau(LP)based on data acquired from 87 meteorological stations from 1960 to *** on the LP basically maintained a spatial pattern of"low in the northwest region and high in the southeast region",and EP over the last 10 a increased *** cumulative precipitation percentage of single day EEP was 34%and was dominant for 60 a,while the cumulative precipitation percentage of front,late,and balanced EEP types associated with PSP accounted for 66%,which confirms to the connotation of *** cumulative frequencies of front and late EEP types were 23%and 21%,respectively,while the cumulative frequency of balanced EEP had the lowest value at only 13%.Moreover,global warming could lead to more single day EEP across the LP,and continuous EEP could increase in the northwestern region and decrease in the eastern region in the *** concept of process-oriented EP could facilitate further exploration of disaster-causing processes associated with different types of EP,and provide a theoretical basis for deriving precipitation disaster chains and construction of disaster cluster characteristics.

关键词： temporal and spatial variation climate change extreme precipitation(EP) event-based extreme precipitation(EEP) Loess Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characteristics of Dried soil Layers Under Apple Orchards of Different Ages and Their Applications in soil Water Managements on the Loess Plateau of China

引用

Pedosphere 2015年第4期25卷 546-554页

作者： WANG Yunqiang SHAO Mingan LIU Zhipeng ZHANG Chencheng State key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences State key laboratory of soil erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources key laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences

Negative soil water balance （i.e., water input 〈 water output） can lead to soil desiccation and subsequently the occurrence of a dried soil layer （DSL）. The DSLs are generally studied at a specific sampling depth （e.g., 500 cm）, and the actual extent of DSLs remains unknown due to the challenge of collecting deep soil samples. To investigate the characteristics of actual DSLs under different ages of apple orchards and ascertain the optimal age of apple orchards for avoiding/controlling the formation of DSLs, soil samples were collected to a depth of 1800 cm under apple orchards of different ages in Changwu on the Loess Plateau of China. As the ages increased, soil water content （SWC） and mean SWC in DSLs showed an overall decreasing trend, whereas while DSL thickness and the quantity of water deficit （QWD） in DSLs demonstrated an increasing trend. The DSL was the thickest （1 600 cm） under the 17-yeax-old orchard, the forming velocity of DSL thickness was the highest at the apple tree growth stage of 9-17 years （168 cm year-l）, and the highest increasing velocity of QWD （-181 mm year-1） was also observed at this stage. The thickness of DSL was significantly correlated with growth age and root depth of apple trees （r 〉 0.88）, whereas the QWD and mean SWC in DSLs were found to have no correlation with them. The optimal age of apple orchards for avoiding/controlling the formation of DSLs was about 9 years. This information provided pertinent references for the management of deep water resources by controlling the growth age of plants. key Words： deep soil, growth age, plant roots, soil desiccation, soil water content, soil-plant water relation.

关键词： deep soil growth age plant roots soil desiccation soil water content soil-plant water relation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Drying-rewetting cycles reduce bacterial diversity and carbon loss in soil on the Loess Plateau of China

引用

Pedosphere 2023年第6期33卷 838-848页

作者： Panpan JIAO Haibing XIAO Zhongwu LI Lei YANG Peng ZHENG State key laboratory of soil erosion and Dryland Farming on the Loess Plateau Research Center of Soil and Water Conservation and Ecological EnvironmentChinese Academy of Sciences and Ministry of EducationYangling 712100China Institute of soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China University of Chinese Academy of Sciences Beijing 100049China State Environmental Protection key laboratory of soil Health and Green Remediation Huazhong Agricultural UniversityWuhan 430070China College of Resources and Environmental Sciences Hunan Normal UniversityChangsha 410081China key laboratory of soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

With global climate change, soil drying-rewetting(DRW) events have intensified and occurred frequently on the Loess Plateau of China. However, the extent to which the DRW cycles with different wetting intensities and cycle numbers alter microbial community and respiration is barely understood. Here,indoor DRW one and four cycles treatments were implemented on soil samples obtained from the Loess Plateau, involving increase of soil moisture from10% water-holding capacity(WHC) to 60% and 90% WHC(i.e., 10%–60% and 10%–90% WHC, respectively). Constant soil moistures of 10%, 60%,and 90% WHC were used as the controls. The results showed that bacterial diversity and richness decreased and those of fungi remained unchanged under DRW treatments compared to the controls. Under all moisture levels, Actinobacteriota and Ascomycota were the most dominant bacterial and fungal phyla,respectively. The bacterial network was more complex than that of fungi, indicating that bacteria had a greater potential for interaction and niche sharing under DRW treatments. The pulse of respiration rate declined as the DRW cycle increased under 10%–60% WHC, but remained similar for different cycles under 10%–90% WHC. Moreover, the DRW treatments reduced the overall carbon loss, and the direct carbon release under 10%–60% WHC was larger than that under 10%–90% WHC. The cumulative CO_(2) emissions after four DRW cycles were significantly positively correlated with microbial biomass carbon and negatively correlated with fungal richness(Chao 1).

关键词： bacterial network cumulative CO_(2)emissions fungal richness microbial biomass carbon microbial community respiration rate soil moisture

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Arbuscular mycorrhizal fungi communities associated with wild plants in a coastal ecosystem

引用

Journal of Forestry Research 2021年第2期32卷 683-695页

作者： Jinping Wang Shilin Ma G.Geoff Wang Linhao Xu Zhiyuan Fu Juan Song Jinchi Zhang Co-Innovation Center for Sustainable Forestry in Southern China Jiangsu Province Key Laboratory of Soil and Water Conservation and Ecological RestorationNanjing Forestry University159 Longpan RoadNanjing 210037JiangsuChina Department of Forestry and Environmental Conservation Clemson UniversityClemsonSC 29634USA

Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant *** little is known about the structure and composition of AMF communities on coastal beaches of eastern *** this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,*** all of the local wild species were colonized by AMF except for Chenopodium album ***-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven *** was the dominant genus and Funneliformis mosseae the dominant *** colonization,spore composition and diversity of AMF were strongly related to edaphic ***(Na^(+))ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na^(+)levels and pH had a significant negative effect on AMF spore density and ***,there was a significant positive correlation between species richness and total organic *** results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.

关键词： AMF diversity Coastal beach Edaphic factors Mycorrhizal composition Wild hosts

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：