检索结果-内蒙古大学图书馆

SSRN 2022年

作者： Li, Yong Wang, Zhaosheng Huang, Mei Gong, He Sun, Hongfu Zhu, Lin National Ecosystem Science Data Center Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China College of Geoscience and Surveying Engineering China University of Mining and Technology Beijing100083 China National Satellite Meteorological Center China Meteorological Administration Beijing China

Biomass energy is a key component of renewable new energy, which is very important for energy security and environmental protection. Meanwhile, Asia is a region with intensive global energy consumption. It is of great significance to clarify its biomass energy potential and its role in energy and environment. So, we used MODIS NPP to evaluate potential biomass energy reserves and their temporal and spatial changes in Asia. The results show that the total potential biomass energy in Asia is 327.68 ± 11.11 EJ, which is approximately equal to the total energy use in all of Asia over the four years. In addition, we used the AHP and cluster analysis to investigate the degree of energy shortage in Asian *** supplying biomass energy for energy use in various countries, the number of countries with severe, moderate and mild energy shortages in Asia will decrease by 8.5%, 12.7% and 6.4% respectively. In addition, if 50% of conventional energy in Asia is replaced by biomass, its total carbon dioxide emissions will be reduced by 33% to 44%. Taken together, this shows that Asia's abundant biomass energy reserves can help alleviate energy shortages in various countries and reduce regional carbon dioxide emissions. © 2022, The Authors. All rights reserved.

关键词： Energy security

来源：评论

学校读者我要写书评

暂无评论

Correction to: Species-specific and generalized allometric biomass models for eight Fagaceae species in the understory of evergreen broadleaved forests in subtropical China

引用

Journal of Forestry Research 2024年第6期35卷 374-374页

作者： Meng, Shengwang Qianyanzhou Ecological Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing People’s Republic of China

In the original publication, the author has found few errors in the equations as below:1. The ε_(fO) symbol in Wag model of Eq. (6) should be deleted. The incorrect equation appears as below.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Improvement of an aerodynamic roughness model with meteorological measurements and TM image

Improvement of an aerodynamic roughness model with meteorolo...

引用

International Conference on Geoinformatics

作者： Yanlian Zhou Xiaomin Sun Weimin Ju School of Geographic and Oceanographic Sciences Nanjing University Nanjing China Key Laboratory of Ecosystem Network Observation Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy and Sciences Beijing China International Institute for earth system science Nanjing University Nanjing China

ISBN: (纸本)9781424445622

Aerodynamic roughness length (z 0 ) is one of the main parameters for describing aerodynamic characteristics and turbulence exchange of underlying surfaces. It also plays a very important role in land surface fluxes simulation and atmospheric boundary layer studies. In fluxes and atmospheric numerical simulation models, z 0 is usually considered as a simple parameter related to rough elements, while actually z 0 is the result of aerodynamic and thermal factors and rough elements. Some researchers on z 0 established a model to calculate effective roughness at TM pixel scale. But in the model, the length of the fetch is simply considered as 100 times of the highest measuring height, which results in much uncertainty of the model. With the development of eddy covariance observations and the footprint theory, fetch could be determined with more accurate footprint model. This paper aims to make an improvement for the model basing on footprint model, and clarify the relationship between z 0 and air temperature, wind speed and geometric roughness. Firstly meteorological data in two different levels was obtained to calculate z 0 and the calculated z 0 was considered as the real value, and then the fetch length was calculated by FSAM footprint model. Secondly LAI was retrieved from TM image to calculate geometric roughness. Thirdly drag coefficient was taken into the roughness calculation model, and then a roughness calculation model was established with footprint model and LAI, vegetation height, atmospheric stratifications and drag coefficient. The result indicated that z 0 is the function of thermal and aerodynamic factors, and the reason for roughness dynamic was interpreted thoroughly. The quantitative relationship between rough elements and aerodynamic and thermal factors is clarified, and a more accurate model for retrieving z 0 at TM pixel scale could be established with the fetch determined by footprint.

关键词： Aerodynamics Meteorology Atmospheric modeling Thermal factors Land surface Rough surfaces Surface roughness Solid modeling Atmospheric measurements Numerical simulation

来源：评论

学校读者我要写书评

暂无评论

Retrieving wheat Biomass by using a hyper-spectral device on UAV

引用

Advances in Animal Biosciences 2017年第2期8卷 833-836页

作者： L. Xia R.R. Zhang L.P. Chen Y. Wen F. Zhao J.J. Hou Beijing Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry Sciences Beijing China Beijing Key Laboratory of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry Sciences Beijing 100081 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research University of Chinese Academy of Science Beijing China

In this study, the biomass of winter wheat was estimated by using hyperspectral data obtained from a hyperspectral camera on an Unmanned Aerial Vehicle (UAV). Every two bands from the hyperspectral data were selected to calculate two kinds of vegetation indexes: the Normalized Difference Vegetation Index (NDVI) and Ratio Vegetation Index (RVI). Linear models were established between winter wheat biomass and those indexes, and coefficient of determination R2 was used to draw the two-dimensional distribution of R2 values. The comparison between NDVI and RVI for pixel covered by soil and wheat showed that RVI is more efficient to mask the influence from soil than NDVI. For calculating the NDVI, optimal bands are located mainly around 820 nm and 725 nm to 750 nm. For assessing RVI, the wavelength range from 820 to 832 nm, 794 to 808 nm, 770 to 788 nm, 725 nm to 750 nm and 890 nm for RVI are most suitable. Those optimal bands can achieve a coefficient of determination R2 higher than 0.88 by using the linear regression model in the study.

关键词： wheat biomass UAV hyperspectral

来源：评论

学校读者我要写书评

暂无评论

Sources of organic carbon supporting the dry-season food web of a sublake in wetlands of Poyang Lake

Sources of organic carbon supporting the dry-season food web...

引用

“全球变化下的海洋与湖沼生态安全”学术交流会

作者： Huan ZHANG Yuyu WANG Shaoxia XIA Bin CHEN Xiubo YUA Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences College of Nature Conservation Beijing Forestry University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Benthic food web in lakes is generally supported by autochthonous primary production, and by terrestrial detritus derived from the surrounding catchment. Several studies have highlighted the importance of allochthonous input, but the effects of subsidy of that carbon source are not well understood in floodplain lakes of wetland, especially when thousands of herbivorous migrated waterfowl winter in that area and the water level is deceding. With stable isotope signatures(δ13C and δ15N) of four primary food sources and aquatic consumers, we used SIAR model to identify the relative importance of different production sources supporting the macroinvertebrate food web in a floodplain sublake of wetlands in Lake Poyang during the late dry season. Our data showed that Carex spp. was the predominant primary food source, potentially contributing 35%3% organic carbon to the biomass of aquatic consumers in the sublake of wetlands, although its C:N ratio was much lower than other sources. For most of macroinvertebrate species, phytoplankton, and possibly particulate organic matter in the seston, were the other major carbon sources that they utilized. However, we did not find benthic algae or Vallisneria natans as thought to be important food sources for benthic primary consumers due to their low biomass during the cold and low water period. Our findings underpin the importance of allochthonous carbon sources, and further provide a view that migratory waterfowl may facilitate those subsidize which can support the biomass and productivity of consumer taxa in wetlands of Lake Poyang when availability of food sources is limited.

关键词： allochthonous Carex spp. macroinvertebrates wetland stable isotope

来源：评论

学校读者我要写书评

暂无评论

Small-scale switch in cover-perimeter relationships of patches indicates shift of dominant species during grassland degradation

引用

Journal of Plant Ecology 2020年第6期13卷 704-712页

作者： Ming-Hua Song Johannes HCCornelissen Yi-Kang Li Xing-Liang Xu Hua-Kun Zhou Xiao-Yong Cui Yan-Fen Wang Rong-Yan Xu Qi Feng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Systems Ecology Department of Ecological ScienceFaculty of Earth and Life SciencesVU UniversityDe Boelelaan 10851081 HV AmsterdamThe Netherlands College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Plant Science Research Center Shanghai Key Laboratory of Plant Functional Genomics and ResearchPlant Science Research CenterShanghai Chenshan Botanic GardenShanghai 201602China Key Laboratory of Ecohydrology of Inland River Basin Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Aims Grasslands are globally threatened by climate changes and unsustainable land-use,which often cause transitions among alternative stable states,and even catastrophic transition to *** vegetation patch configurations have been shown to signify such transitions at large spatial ***,we demonstrate how small-scale patch configurations can also indicate state *** The whole spatial series of degradation successions were chosen in alpine grasslands characterized as seven typical *** numbers,and perimeter and cover of each patch were recorded using adjacent quadrats along transects in each type of the *** abundance within each patch was *** Findings Across seven grazing-induced degradation stages in the world’s largest expanse of grassland,from dense ungrazed turf to bare black-soil crust,patch numbers and perimeters first increased as patch cover *** and perimeters then decreased rapidly beyond an intersection point at 68%of initial continuous vegetation *** this point,the vegetation fluctuated back and forth between the sedge-dominated grassland breaking-up phase and the forb-dominated phase,suggesting impending shift of grassland *** study thus demonstrates how ground-based small-scale vegetation surveys can provide a quantitative,easy-to-use signals for vegetation degradation,with promise for detecting the catastrophic transition to desertification.

关键词： grassland degradation state transition Tibetan Plateau trade-off vegetation patchiness

来源：评论

学校读者我要写书评

暂无评论

Alpine Grassland Aboveground Biomass and Theoretical Livestock Carrying Capacity on the Tibetan Plateau

引用

Journal of Resources and Ecology 2022年第1期13卷 129-141页

作者： ZHANG Xianzhou LI Meng WU Jianshuang HE Yongtao NIU Ben Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences andNatural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China School of Geographic Sciences Nantong UniversityNantongJiangsu 226007China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China

The accurate simulation and prediction of grassland aboveground biomass (AGB) and theoretical livestock carrying capacity are key steps for maintaining ecosystem balance and sustainable grassland *** AGB in fenced grassland is not affected by grazing and its variability is only driven by climate change,which can be regarded as the grassland potential AGB (AGB_(p)).In this study,we compiled the data for 345 AGB field observations in fenced grasslands and their corresponding climate data,soil data,and topographical data on the Qinghai-Tibetan Plateau (TP).We further simulated and predicted grassland AGB_(p)and theoretical livestock carrying capacity under the climate conditions of the past (2000-2018) and future two decades (2021-2040) based on a random forest (RF) *** results showed that simulated AGB_(p)matched well with observed values in the field (R^(2)=0.76,P<0.001) in the past two *** average grassland AGB_(p)on the Tibetan Plateau was 102.4g m^(-2),and the inter-annual changes in AGB_(p)during this period showed a non-significant increasing ***_(p)fluctuation was positively correlated with growing season precipitation (R^(2)=0.57,P<0.001),and negatively correlated with the growing season diurnal temperature range (R^(2)=0.51,P<0.001).The average theoretical livestock carrying capacity was 0.94 standardized sheep units (SSU) ha^(-1)on the TP,in which about 54.1%of the areas showed an increasing trend during the past two *** with the past two decades,the theoretical livestock carrying capacity showed a decreasing trend in the future,which was mainly distributed in the central and northern *** study suggested that targeted planning and management should be carried out to alleviate the forage-livestock contradiction in grazing systems on the Tibetan Plateau.

关键词： alpine grassland aboveground biomass carrying capacity climate change random forest Tibetan Plateau

来源：评论

学校读者我要写书评

暂无评论

Effect of Land Use and Land Cover Change on the Changes in Net Primary Productivity in Karst Areas of Southwest China:A Case Study of Huanjiang Maonan Autonomous County

引用

Journal of Resources and Ecology 2020年第6期11卷 606-616页

作者： ZHANG Mengyu ZHANG Li REN Xiaoli HE Honglin LV Yan WANG Junbang YAN Huimin Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China National Ecosystem Science Data Center Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Key Laboratory of Resource Utilization and Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Karst areas in southwest China have experienced significant land cover and land use change(LUCC)due to utilization for human activity and a comprehensive rocky desertification control project(RDCP)since *** is important to quantify the effect of LUCC on ecosystem productivity in this region for assessing the overall benefit of this ecological restoration *** this study,we used using MODIS land cover and NPP products to investigate the relative contribution of LUCC to the change in net primary productivity(NPP)during 2008–2013 in Huanjiang County,one of first one hundred pilot counties to implement *** results show that NPP increased in 95.53%of the county,and the average growth of NPP in non-rocky desertification area was higher than in rocky desertification or potential rocky desertification *** has an important contribution(25.23%)to the NPP increase in the county,especially in the LUCC area(70.97%),which increased the average NPP by 3.9%and 10.5%,*** the six RDCP regions in the county,the average increase in NPP for the vegetation restoration measure of governed karst area is significantly greater than in the ungoverned karst area,and the positive change in NPP increased with the increasing implementation area of the vegetation restoration measure.

关键词： land use change net primary productivity karst area comprehensive control project for rocky desertification

来源：评论

学校读者我要写书评

暂无评论

The Rangeland Livestock Carrying Capacity and Stocking Rate in the Kailash Sacred Landscape in China

引用

Journal of Resources and Ecology 2017年第6期8卷 551-558页

作者： DUAN Cheng SHI Peili ZHANG Xianzhou ZONG Ning CHAI Xi GENG Shoubao ZHU Wanrui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100190 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100190 China

Maintaining the health and productivity of rangelands by controlling the livestock stocking rate to remain within carrying capacity is of significance to ensure sustainable management of rangeland ecosystems. But we know little about the safe carrying capacity in particular rangeland landscapes. This has hampered efforts to use rangelands in a risk-averse manner in fluctuating rainfall environments, and especially in arid and semiarid areas. To address this lack of information, we took Kailash Sacred Landscape in China（KSL-China） as our study site and used remote sensing data, meteorological data and statistical data from 2000 to 2015 to analyze rangeland carrying capacity, stocking rate, and major influencing factors. Rangeland carrying capacity presented an increasing trend, while stocking rate was gradually decreasing, resulting in an increase of carrying rate in the study area. The increased carrying capacity was closely related to increased rainfall. Stocking rate declined owing to government regulations, particularly implementation in 2004 of the national policy of Returning Grazing Land to Grassland. There was a sharp reduction of livestock number below 200 000 standard sheep units（SU） after 2005. The decrease of stocking rate had a stronger effect on rangeland carrying rate than did the increase of carrying capacity. ecosystem restoration programs have provided subsidies to pastoralists to encourage them to reduce livestock numbers. Our findings suggest that a safe rangeland carrying capacity is ca. 170 000 SU in KSL-China. There is a carrying capacity surplus of ca. 50 000 SU for safe animal husbandry development in the study area. More importantly, future climate warming and increases in grazing may jointly play a key role in affecting rangeland carrying capacity.

关键词： Kailash Sacred Landscape in China rangeland net primary productivity safe carrying capacity stocking rate

来源：评论

学校读者我要写书评

暂无评论

Fungal Necromass Contribute More to Organic Carbon Sequestration than Bacterial Necromass in Tobacco-Planted Field

SSRN

引用

SSRN 2023年

作者： Tang, Zuoxin Feng, Junna Chen, Lulu Chen, Zebin Shao, Xiaodong Xia, Tiyuan College of Agricultural and Life Sciences Kunming University Yunnan Kunming650214 China Key Laboratory of Ecosystem Network Observation and Modeling Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China Honghe Branch of Yunnan Tobacco Company Mile Yunnan652300 China

Microbial necromass carbon (MNC) is an important component of soil organic carbon (SOC). Although the contribution of MNC to stable SOC pool has been recognized, the response of MNC to fertilization in flue-cured tobacco growing soils is rarely studied. In this study, microbial biomarkers were extracted from rhizosphere soil and used to measure the relationship between the soil microbial community composition (using phospholipid fatty acids, PLFAs) and MNC (using amino sugars), and the contribution of MNC to SOC and its fractions (including particulate and mineral-associated organic carbon (POC and MAOC)) under compound and microbial fertilizer addition. The results showed that the accumulation of amino sugars and MNC increased with the growth period and was affected by the limitation of microbial resources. Compared with other treatments, compound fertilizer reduction combined with microbial fertilizer treatment increased the content of amino sugars and MNC, especially during the harvest period. The contribution of MNC to SOC varied from 38.03% to 50.49%, while the contribution of fungal necromass carbon (FNC) to SOC, POC, and MAOC was approximately three times that of bacterial necromass car-bon (BNC). The content of MNC and FNC increased significantly with the increase of POC, and POC accumulation rate is greater than MAOC. By forming POC, the contribution of fungal necro-mass carbon to SOC was promoted. While the relationship between MAOC and BNC was closer than that of FNC. Hence, bacterial necromass carbon was involved in SOC turnover while fungal necromass carbon dominantly contribute to SOC accumulation. In addition, microbial biomass and microbial community structure composition are important determinants of amino sugars and MNC. Summarizing, these results provided a new idea for the microbial mechanism of controlling carbon persistence in tobacco planting soil, and the POC and MAOC components, and microbial fertilizer partially replace compound fertilizer

关键词： Organic carbon

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：