检索结果-南通市图书馆

Soil type-dependent effects of drying-wetting sequences on aggregates and their associated OC and N

International Soil and Water Conservation Research 2022年第4期10卷 649-661页

作者： Na Mao Xiaorong Wei mingan shao State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling712100China Institute of Soil and Water Conservation Northwest A&F UniversityYangling712100China CAS Center for Excellence in Quaternary Science and Global Change Xi'an710061China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China

Evaluating the impacts of drying-wetting(DW)cycles on soil aggregates and their associated organic carbon(OC)and nitrogen(N)is crucial to understand the OC and N *** are likely subjected to DW cycles with different sequences depending on seasons or in ***,studies on how DW sequences influence OC and N dynamics within aggregates,and whether this effect is dependent on soil type,are relatively ***,two DW sequences,i.e.,drying-wetting-dryingwetting(2DW)and wetting-drying-wetting-drying(2WD)treatments were designed,and a consistent wetting(CW)was set as a control to assess the effects of DW *** soils(Entisol,Ultisol,Anthrosol and Mollisol)varying in texture and OC content were *** aggregate size distribution,the OC,total N(TN),readily oxidizable OC(ROOC)and mineral N(Min-N)content in aggregates were *** showed that 2DW treatment increased but 2WD treatment decreased the large aggregates of Entisol and Ultisol,while 2DW and 2WD treatments synchronously increased the large aggregates of Anthrosol but decreased them of *** DW treatments increased the OC in each aggregate of Entisol,Anthrosol and Mollisol but decreased them of *** 2DW didn't affect but 2WD treatment decreased ROOC in 1e2 mm aggregates of Entisol and<0.25 mm aggregates of Ultisol and *** 2DW and 2WD treatments minimally affected TN but potentially influenced Min-N in *** 2DW and 2WD treatments both decreased the Min-N in each aggregate size class of Entisol and Mollisol,while 2DW increased but 2WD treatment decreased Min-N in each aggregate of Ultisol and *** results indicated that the varied effects of DW sequences and the interactive effects of soil type with DW sequences on aggregate turnover and OC and N cycling should be reconsidered to provide more precisive evidences for global C and N cycles under the scenario of future climate changes.

关键词： Aggregates Carbon Nitrogen Drying-wetting sequences Soil type

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Estimation and testing of linkages between forest structure and rainfall interception characteristics of a Robinia pseudoacacia plantation on China’s Loess Plateau

引用

Journal of Forestry Research 2022年第2期33卷 529-542页

作者： Changkun Ma Yi Luo mingan shao Xiaoxu Jia State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xian University of TechnologyXianChina Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

Understanding the interaction between canopy structure and the parameters of interception loss is essential in predicting the variations in partitioning rainfall and water resources as affected by changes in canopy structure and in implementing water-based management in semiarid forest *** this study,seasonal variations in rainfall interception loss and canopy storage capacity as driven by canopy structure were predicted and the linkages were tested using seasonal filed *** study was conducted in nine 50 m×50 m Robinia pseudoacacia plots in the semiarid region of China’s Loess *** rain-fall,throughfall and stemflow were measured in seasons with and without leaves in 2015 and *** show that measured average interception loss for the nine plots were 17.9% and 9.4% of gross rainfall during periods with leaves (the growing season) and without leaves, respectively. Average canopy storage capacity estimated using an indirect method was 1.3 mm in the growing season and 0.2 mm in the leafless season. Correlations of relative interception loss and canopy storage capacity to canopy variables were highest for leaf/wood area index (LAI/WAI) and canopy cover, fol-lowed by bark area, basal area, tree height and stand density. Combined canopy cover, leaf/wood area index and bark area multiple regression models of interception loss and canopy storage capacity were established for the growing season and in the leafless season in 2015. It explained 97% and 96% of the variations in relative interception loss during seasons with and without leaves, respectively. It also explained 98% and 99% of the variations in canopy storage capacity during seasons with and without leaves, respectively. The empiri-cal regression models were validated using field data col-lected in 2016. The models satisfactorily predicted relative interception loss and canopy storage capacity during seasons with and without leaves. This study provides greater under-standing a

关键词： Rainfall interception loss Canopy storage Canopy structure Regression models China’s 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

Humic acid transport in saturated porous media:Influence of flow velocity and influent concentration

引用

Journal of Environmental Sciences 2014年第12期26卷 2554-2561页

作者： Xiaorong Wei mingan shao Lina Du Robert Horton State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Department of Agronomy Iowa State University Ames IA 50011 USA

Understanding the transport of humic acids（HAs） in porous media can provide important and practical evidence needed for accurate prediction of organic/inorganic contaminant transport in different environmental media and interfaces. A series of column transport experiments was conducted to evaluate the transport of HA in different porous media at different flow velocities and influent HA concentrations. Low flow velocity and influent concentration were found to favor the adsorption and deposition of HA onto sand grains packed into columns and to give higher equilibrium distribution coefficients and deposition rate coefficients, which resulted in an increased fraction of HA being retained in ***, retardation factors were increased and the transport of HA through the columns was delayed. These results suggest that the transport of HA in porous media is primarily controlled by the attachment of HA to the solid matrix. Accordingly, this attachment should be considered in studies of HA behavior in porous media.

关键词： Attachment Flow velocity Humic acid Initial concentration Porous media Transport

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

Fractions and Bioavailability of Soil Inorganic Phosphorus in the Loess Plateau of China under Different Vegetations

引用

Acta Geologica Sinica(English Edition) 2011年第1期85卷 263-270页

作者： WEI Xiaorong shao mingan shao Hongbo GAO Jianlun XU Gang State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau NorthwestA ＆ F University Yangling 712100 China The CAS/Shandong Provincial Key Laboratory of Coastal Environmental Process Yantai Institute of Costal Zone Research Chinese Academy of Sciences （CAS） Yantai 264003 China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources （CAS ＆ MWR） Yangling 712100 China Institute for Life Sciences Qingdao University of Science ＆ Technology Qingdao 266042 China Mizhi Meteorological Office of Shaanxi Province Mizhi 718100 China

Plants play an important role in soil phosphorus nutrition. However, the effect of plants on phosphorus nutrition in soils of the Loess Plateau of China is not well understood. This study was conducted to reveal the relationships between plants and phosphorus＇ fractions and availability in the Loess Plateau of China. Twenty-two plant communities were surveyed and soil samples under different plant canopies were collected for the determination of soil properties and inorganic phosphorus fractionation. The results showed that Leguminosae and Lilaceae reduced pH and increased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies, while Labiatae and Rosaceae increased pH and decreased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies. The contents of Ca2P, CasP, AI-P and Fe-P were highly related with soil Oisen phosphorus. They were all higher in soils under Leguminosae and Lilaceae and lower in softs under Labiatae and Rosaceae. The results of this study indicate that Leguminosae and Lilaceae improved phosphorus nutrition in soils, yet Labiatae and Rosaceae impeded the improvement of phosphorus nutrition in soils under their canopies, which will be of more help to instruct vegetation restoration in the region and provide information for soil development.

关键词： bioavailability fraction inorganic phosphorus vegetation soil development 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

Response of soil CO_2 efflux to precipitation manipulation in a semiarid grassland

引用

Journal of Environmental Sciences 2016年第7期28卷 207-214页

作者： Xiaorong Wei Yanjiang Zhang Jian Liu Hailong Gao Jun Fan Xiaoxu Jia Jimin Cheng mingan shao Xingchang Zhang State Key Laboratory of Soil Erosion and Dryland Farming in the Loess Plateau Northwest A&F University College of Animal Science and Technology Northwest A&F University Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences

Soil CO_2efflux（SCE） is an important component of ecosystem CO_2 exchange and is largely temperature and moisture dependent, providing feedback between C cycling and the climate system. We used a precipitation manipulation experiment to examine the effects of precipitation treatment on SCE and its dependences on soil temperature and moisture in a semiarid grassland. Precipitation manipulation included ambient precipitation, decreased precipitation（- 43%）, or increased precipitation（＋ 17%）. The SCE was measured from July2013 to December 2014, and CO_2 emission during the experimental period was *** response curves of SCE to soil temperature and moisture were analyzed to determine whether the dependence of SCE on soil temperature or moisture varied with precipitation manipulation. The SCE significantly varied seasonally but was not affected by precipitation treatments regardless of season. Increasing precipitation resulted in an upward shift of SCE–temperature response curves and rightward shift of SCE–moisture response curves,while decreasing precipitation resulted in opposite shifts of such response curves. These shifts in the SCE response curves suggested that increasing precipitation strengthened the dependence of SCE on temperature or moisture, and decreasing precipitation weakened such dependences. Such shifts affected the predictions in soil CO_2 emissions for different precipitation treatments. When considering such shifts, decreasing or increasing precipitation resulted in 43 or 75% less change, respectively, in CO_2 emission compared with changes in emissions predicted without considering such shifts. Furthermore, the effects of shifts in SCE response curves on CO_2 emission prediction were greater during the growing than the non-growing season.

关键词： Soil CO2 efflux response curve Soil moisture Soil temperature Precipitation regimes Semiarid grassland Soil CO2 efflux

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

Roles of ABA Signal Transduction during Higher Plant Seed Development and Germination

引用

Forestry Studies in China 2003年第4期5卷 45-53页

作者： shao Hongbo Liang Zongsuo shao mingan Bio-information College of Chongqing University of Posts and Telecommunications Chongqing 400065P.R.China The National Key Laboratory of Soil Erosion and Dryland Farming Research Centre of Soil and Water Conservation and Eco-environmentChinese Academy of SciencesYangling 712100P.R.China Northwest Sci-tech University of Agriculture and Forestry Yangling 712100P.R.China Institute for Graphical Sciences and Resource Chinese Academy of SciencesBeijing 100101P.R.China

ABA is one of the 5 phytohormones in higher plants, which is also the most important hormone that regulates higher plants in response to environmental stress, by ABA signal transduction. Understanding ABA signal transduction at the molecular level is crucial to biology and ecology, and rational breeding complied with corresponding eco-environmental changes. Great advancements have taken place over the past 10 years by application of the Arabidopsis experimental system. Many components involved in ABA signal transduction have been isolated and identified and a clear overall picture of gene expression and control for this transduction has become an accepted fact. On the basis of the work in our laboratory, in conjunction with the data available at the moment, the authors have attempted to integrate ABA signal transduction pathways into a common one and give some insights into the relationship between ABA signal transduction and other hormone signal transduction pathways, with an emphasis upon the ABA signal transduction during higher plant seed development. A future challenge in this field is that different experimental systems are applied and various receptors and genes need to be characterized through the utilization of microarray chips.

关键词： molecular biology ABA signal transduction ABA-responsive genes seed development environmental stresses

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

MODELING OF INTERRILL EROSION INTHE LOESS PLATEAU OF CHINA

引用

International Journal of Sediment Research 1999年第2期14卷 319-324页

作者： Zhanbin LI mingan shao & Zhanli WANG Bing SHEA (Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water resources. Yangling, Shaanxi 712100, China Xi'an University of Technology , Xi'an , Shaanxi 710048, China)

Based on the field plots data from simulated rainfall experiments, a theoretical model for calculating the kinetic energy of a single raindrop was developed in the Loess Plateau of China Formulae for both single raindrops and rainfall events are presented in this *** shows that overland flow and the area producing runoff on the land surface increase with the duration of rainfall, while the effects of raindrop impact on the surface of the hillslope decrease. The rate of interrill erosion decreases gradually with the rainfall duration. A physically-based formula to calculating the area of runoff production is also given in this paper The overland flow and canopy affect jointly the interrill erosion processes. The paper presents an equation to quantitatively evaluate the effect. It is concluded thats (1) the peak rate of interrill erosion is related to rainfall intensity, rainfall kinetic energy, and slope; and (2) the average rate of interrill erosion during an individual time period for variable rainfall intensity varies with the rainfall intensity, rainfall duration and runoff producing area.

关键词： Interrill erosion Splash erosion Rainfall kinetic energy Runoff producing area.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Interview with optical scientist and engineer Joseph Braat

引用

Advanced Photonics 2024年第3期6卷 7-12页

作者： Yifeng shao Delft University of Technology

Joseph Braat(professor emeritus TU Delft and former research fellow at Philips Research) received the 2019 Holst Memorial Lecture Award for his important contributions in to diffractionlimited optical imaging and scan...

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

黄土区坡地和坝地土壤电阻率分布特征及应用

引用

土壤学报 2022年第1期59卷 139-147页

作者：刘成功贾小旭赵春雷邵明安中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室北京100101 中国科学院大学资源与环境学院北京100190

土壤水分的准确高效测定是土壤水文学研究的重要基础,以土壤电学性质为基础的电阻率成像法(ERT)为土壤水分信息获取提供了新的技术手段。为探究ERT在黄土区土壤水文过程研究中的可行性,利用高密度电法仪测定了陕北六道沟小流域典型坡地... 详细信息

土壤水分的准确高效测定是土壤水文学研究的重要基础,以土壤电学性质为基础的电阻率成像法(ERT)为土壤水分信息获取提供了新的技术手段。为探究ERT在黄土区土壤水文过程研究中的可行性,利用高密度电法仪测定了陕北六道沟小流域典型坡地和坝地剖面土壤电阻率(ρ),分析了不同土地利用方式下ρ二维分布特征,探讨了ERT在黄土区土壤水分及地下水监测研究方面的应用。结果表明:坡地土地利用方式和坡位对ρ具有显著影响,剖面平均ρ由高到低依次为:柠条灌木地>苜蓿草地>撂荒草地>农耕地,坡顶ρ显著高于坡底,这与土壤含水量高低有密切关系。坝地ρ具有明显的水平和垂直分异特征,垂直方向呈高阻层—低阻层—高阻层分布,低阻层上边界与浅层地下水位一致。在坝地尾部,低阻层厚度增加并穿透浅层高阻层,可能与尾部作物耗水较少有关。ERT可用于黄土区不同土地利用方式下土壤干湿状况及坝地地下水动态监测研究。

关键词：土壤电阻率土壤水分地下水土地利用黄土高原

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：