检索结果-内蒙古大学图书馆

Modelling the integrated effects of land use and climate change scenarios on forest ecosystem aboveground biomass, a case study in Taihe County of China

引用

Journal of Geographical Sciences 2017年第2期27卷 205-222页

作者： WU Zhuo DAI Erfu GE Quansheng XI Weimin WANG Xiaofan Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and NaturalResources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Department of Biological and Health Sciences Texas A&M University Kingsville Texas 78363 USA Key Laboratory of Land Use Ministry of Land and Resources China Land-Surveying and Planning InstituteBeijing 100035 China

Global and regional environmental changes such as land use and climate change have significantly integrated and interactive effects on forest. These integrated effects will undoubtedly alter the distribution, function and succession processes of forest ecosystems. In order to adapt to these changes, it is necessary to understand their individual and integrated effects. In this study, we proposed a framework by using coupling models to gain a better understanding of the complex ecological processes. We combined an agent-based model for land use and land cover change（ABM/LUCC）, an ecosystem process model（PnET-Ⅱ）, and a forest dynamic landscape model（landIS-Ⅱ） to simulate the change of forest aboveground biomass（AGB） which was driven by land use and climate change factors for the period of 2010–2050 in Taihe County of southern China, where subtropical coniferous plantations dominate. We conducted a series of land use and climate change scenarios to compare the differences in forest AGB. The results show that：（1） land use, including town expansion, deforestation and forest conversion and climate change are likely to influence forest AGB in the near future in Taihe County.（2） Though climate change will make a good contribution to an increase in forest AGB, land use change can result in a rapid decrease in the forest AGB and play a vital role in the integrated simulation. The forest AGB under the integrated scenario decreased by 53.7%（RCP2.6 ＋ land use）, 57.2%（RCP4.5 ＋ land use）, and 56.9%（RCP8.5 ＋ land use） by 2050, which is in comparison to the results under separate RCPs without land use disturbance.（3） The framework can offer a coupled method to better understand the complex and interactive ecological processes, which may provide some supports for adapting to land use and climate change, improving and optimizing plantation structure and function,and developing measures for sustainable forest management.

关键词： RCPs plantation forest aboveground biomass ABM landIS-Ⅱ Taihe County

来源：评论

学校读者我要写书评

暂无评论

Phenological records in Guanzhong Area in central China between 600 and 902 AD as proxy for winter half-year temperature reconstruction

引用

Science China Earth Sciences 2016年第9期59卷 1847-1853页

作者： LIU YaChen DAI JunHu WANG HuanJiong YE Yu LIU HaoLong School of Geography Beijing Normal University Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences

Phenological data obtained from historical documents constitute highly important ecological evidence for the pre-instrumental period, and can be used in analyzing climatic change in history. In this study, 87 phenological records about seasonality of non-biological events （e.g., first frost date）, agriculture and ornamental plants （e.g., first flowering date） over 77 years were extracted from historical documents from the Sui and Tang dynasties in China to reconstruct the winter half-year （from October to next April） temperatures in the Guanzhong Area （located in central China） from 600 to 902 AD. Transfer functions between temperature and phenophases with significant correlations were established by using modem observation data. Temperatures from the study period were reconstructed by applying the transfer functions to historical phenological data. The reconstruction indicates that the winter half-year temperatures during 600-902 AD were 0.23~C higher than the reference period （1961-1990）. The temperature changed with two distinct stages. During the 600s-800s, temperatures were approxi- mately 0.38~C higher than at present but then temperatures decreased in the subsequent period （800-902 AD）. These results are similar to ones from previous studies on the mean temperature and the divisions between warm and cold periods during the study period, though differences were found in the degree of warmness/coldness. This reconstruction provides a valuable contribution to a better understanding of climatic variability during the Sui and Tang dynasties in China.

关键词： Phenological records Temperature reconstruction Sui and Tang dynasties in China Guanzhong Area in China

来源：评论

学校读者我要写书评

暂无评论

TEMPORAL AND SPATIAL DYNAMICS OF SOIL EROSION IN NORTH-SOUTH PAN RIVER WATERSHED IN 2000-2010

TEMPORAL AND SPATIAL DYNAMICS OF SOIL EROSION IN NORTH-SOUTH...

引用

IEEE International Geoscience and Remote Sensing Symposium

作者： Wei Cao Lulu Liu Dan Wu Zhai Jun Yunfeng Hu Duanyang Xu Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Beijing CAS China School of Architecture and Civil Engineering Chengdu University Chengdu China Ministry of Environmental Protection Nanjing Institute of Environmental Sciences Nanjing China Ministry of Environmental Protection Satellite Environment Center Beijing China

In this study, the Revised Universal Soil Loss Equation (RUSLE) was applied to analyze the spatial and temporal dynamics of soil erosion in North-South Pan River watershed from 2000 to 2010, and the driving factors were discussed. The results showed that: (1) The average annual soil loss per area in North-South Pan River watershed was 14.6 t/hm~2/yr from 2000 to 2010, and the mean annual total soil loss was about 118 million tons. (2) In 2000-2010, the soil erosion showed an obvious decreasing trend with an annual variation of -0.87 t/hm~2/yr in North-South Pan River watershed. The soil erosion decreased in 75.1% of this watershed, and the soil erosion intensity decreased in 23.6% of this watershed which were mainly changed from slight to trivial (10.0%), from moderate to slight (7.7%) and from intensive to moderate (2.9%). (3) The declining of soil erosion in North-South Pan River watershed was mainly caused by the joint effect of climate change and ecological projects. The rainfall erosivity factor decreased greatly according to the observations of meteorological stations. Meanwhile the implementation of ecological projects helped the restoration of forest and grassland, and the vegetation coverage raise greatly with 0.35%/yr increase which can better prevent the occurrence of soil erosion. (4) Though the soil erosion have decreased a lot recently, the ecological environment of North-south Pan River watershed is still extremely vulnerable to further curb the occurrence of soil erosion in this watershed, a long-term mechanism of ecological protection needs to be established.

关键词： Soil Rivers Forestry Vegetation Mathematical model Market research Vegetation mapping

来源：评论

学校读者我要写书评

暂无评论

Global daily CO2 emissions for the year 2020

arXiv

引用

arXiv 2021年

作者： Liu, Zhu Deng, Zhu Ciais, Philippe Tan, Jianguang Zhu, Biqing Davis, Steven J. Andrew, Robbie Boucher, Olivier Arous, Simon Ben Canadell, Pep Dou, Xinyu Friedlingstein, Pierre Gentine, Pierre Guo, Rui Hong, Chaopeng Jackson, Robert B. Kammen, Daniel M. Ke, Piyu Le Quere, Corinne Monica, Crippa Janssens-Maenhout, Greet Peters, Glen Tanaka, Katsumasa Wang, Yilong Zheng, Bo Zhong, Haiwang Sun, Taochun Schellnhuber, Hans Joachim Department of Earth System Science Tsinghua University Beijing100084 China Laboratoire des Sciences du Climate et de l'Environnement LSCE Orme de Merisiers Gif-sur-Yvette91191 France Department of Earth System Science University of California Irvine 3232 Croul Hall IrvineCA92697-3100 United States CICERO Center for International Climate Research Oslo Norway Institute Pierre-Simon Laplace Sorbonne Université/CNRS Paris France Kayrros 33 Rue La Fayette ParisFR 75009 France Global Carbon Project CSIRO Oceans and Atmosphere Australia Capital Territory Australia College of Engineering Mathematics and Physical Sciences University of Exeter Exeter United Kingdom Department of Earth & Environment Sciences Columbia University United States Earth System Science Department Woods Institute for the Environment Precourt Institute for Energy Stanford University StanfordCA United States Energy and Resources Group Goldman School of Public Policy University of California BerkeleyCA United States School of Environmental Science The Tyndall Centre for Climate Change Research University of East Anglia Norwich United Kingdom Ispra Italy Center for Global Environmental Research National Institute for Environmental Studies Tsukuba Japan Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Tsinghua Shenzhen International Graduate School Tsinghua University Shenzheng China Department of Electrical Engineering Tsinghua University Beijing100084 China Potsdam Institute for Climate Impact Research Potsdam14412 Germany

The diurnal cycle CO2 emissions from fossil fuel combustion and cement production reflect seasonality, weather conditions, working days, and more recently the impact of the COVID-19 pandemic. Here, for the first time we provide a daily CO2 emission dataset for the whole year of 2020 calculated from inventory and near-real-time activity data (called Carbon Monitor project: https://***) for power generation (for 29 countries), industry (for 73 countries), road transportation (for 406 cities), aviation and maritime transportation and residential fuel use sectors (which we estimate for 206 countries). It was previously suggested from preliminary estimates that did not cover the entire year of 2020 that the pandemics may have caused more than 8% annual decline of global CO2 emissions. Here we show from detailed estimates of the full year data that the global reduction was only 5.4% (-1,901 MtCO2, ±7.2% for 2-sigma range). This decrease is 5 times larger than the annual emission drop at the peak of the 2008 Global Financial Crisis. However, global CO2 emissions gradually recovered towards 2019 levels from late April with global partial re-opening. More importantly, global CO2 emissions even increased slightly by +0.9% in December 2020 compared with 2019, indicating the trends of rebound of global emissions. Later waves of COVID-19 infections in late 2020 and corresponding lockdowns have caused further CO2 emissions reductions particularly in western countries, but to a much smaller extent than the declines in the first wave. Despite partial mobility restrictions in European countries and in some US States that have been affected by the second and third waves of the pandemics, emission reductions observed in Autumn 2020 were much smaller than those of Spring 2020. That even substantial world-wide lockdowns of activity led to a one-time decline in global CO2 emissions of only 5.4% in one year highlights the significant challenges for climate change mitigation

关键词： Fossil fuels

来源：评论

学校读者我要写书评

暂无评论

Spatio-temporal Differentiation of Residential land for Coastal Town: A Case Study of Dalian Jinshitan

引用

Chinese Geographical Science 2016年第4期26卷 566-576页

作者： YANG Jun SUN Jing ZHAO Hongdan XI Jianchao LI Xueming Liaoning Key Laboratory of Physical Geography and Geomatics Liaoning Normal University Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Based on SPOT5 satellite remote sensing images and land use data in five time phases covering the period 1988–2012, the distribution characteristics, spatial differentiation processes, and driving mechanisms affecting the residential land of the Jinshitan Tourist Resort were studied. The work included a combination of GIS technology, adoption of the differentiation index D, and the multi-group differentiation-measure model D(m). The results provided a basis for the following conclusions: 1) From 1988 to 2012, the degree of differentiation of the rural residential land first decreased, and then increased. The general residential, commercial residential and garden-house land-types all showed declining trends, of which the garden-house type presented the most intense volatility. 2) The overall background of the traditional residential land type was gradually replaced by a new residential land type, and the total area of residential land increased year by year, significantly improving the overall residential conditions. The areas of the new residential land type showed growth, and were increasingly widely distributed in the coastal tourist resorts, transportation corridors, and scenic areas. 3) Government policy, social differentiation, market mechanisms, and individual choices(along with other factors) were mutually promoted, although still restrained. However, all of these factors interacted to constrain the developmental direction and the processes affecting tourism real estate in the Dalian Jinshitan Tourist Resort.

关键词： residential space differentiation differentiation degree residential conditions driving mechanism Dalian Jinshitan

来源：评论

学校读者我要写书评

暂无评论

The influence of urbanization on karst rivers based on nutrient concentration and nitrate dual isotopes： an example from southwestern China

引用

Acta Geochimica 2017年第3期36卷 446-451页

作者： Zhong-Jun Wang Fu-Jun Yue Jie Zeng Si-Liang Li State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 China University of Chinese Academy of Sciences Beijing 100049China Puding Karst Ecosystem Research Station Institute of Geochemistry Chinese Academy of Sciences Anshun 562100 China School of Geographical and Earth Sciences University of Glasgow Glasgow G12 8QQ UK Key Laboratory of Karst Environment and Geohazard Ministry of Land and Resources Guizhou UniversityGuiyang 550025 China Institute of Surface-Earth System Science Tianjin University Tianjin 300072 China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China

China is experiencing rapid urbanization that has changed the water quality of rivers, especially nutrient loads. In this study, a typical urban river located in a karst area, Chengguan River, was chosen to explore the influence of urbanization on river ecosystems based on nutrient concentration and nitrate isotopes. The results show monthly variability of water chemistry and nutrient concentration. Nutrient concentration in two tributaries and the mainstem showed significant spatial variability, with heavy N and P pollution in one tributary near a suburban area,indicating a response to different levels of *** of nitrate dual isotopes suggest thatvolatilization, assimilation, nitrification, and denitrification all occur in the polluted river. Water chemistry and nitrate isotopes show that major nitrogen sources included domestic waste and agricultural input, such as chemical fertilizer and manure. The results suggest that urbanization increases nutrient concentrations and accelerates the riverine nitrogen dynamic, and point to the need to manage point sources of sewage effluents to improve the water quality of urban rivers in southwestern China.

关键词： Urbanization Urban river Nitrate isotopes Southwestern China Chengguan River

来源：评论

学校读者我要写书评

暂无评论

Emergy-based environmental accounting toward a sustainable Mongolia

引用

Journal of Geographical Sciences 2017年第10期27卷 1227-1248页

作者： LI Haitao BROWN Mark Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Center for Environmental Policy Engineering School of Sustainable Infrastructure and Environment University of Florida Gainesville FI 32611 USA

An emergy-based environmental accounting of Mongolia is presented based on the data from 1995 to 2012. By calculating natural and economic inputs and a series of emergy indicators, this paper discusses Mongolia＇s resource use structure, economic situation, trade status and societal sustainability. The results show that the total emergy use for Mongolia changed from 2.83×10^22 sej in 1995 to 4.96×10^22 sej in 2012, representing a 75% increase over the 18 years of this study, yet its emergy per capita remains one of the lowest in the world （1.74× 10^16 sej/capita）. The emergy money ratio （EMR） of Mongolia during 1995-2012 decreased from 1.99×10^13 sej/USD to 7.75×10^12 sej/USD, which indicates that the power of a dollar for purchasing real wealth in Mongolia was declining, while the relatively high absolute values compared to its trading partners and even the world average EMR suggests that Mongolia is continuing a trade disadvantage. Mongolia＇s emergy exchange ratio is increasingly less than one to the point that in 2012 the ratio was 0.3 suggesting that the exported emergy was over 3.3 times greater than the imported emergy. The growing dependence on imports and the dramatic increase in exports suggests that Mongolia＇s economy is increas- ingly vulnerable to downturns in the world economy.

关键词： emergy resources sustainability Mongolia

来源：评论

学校读者我要写书评

暂无评论

Reconstruction of cropland spatial patterns and its spatiotemporal changes over the 20th century on the Songnen Plain, Northeast China

引用

Journal of Geographical Sciences 2017年第10期27卷 1209-1226页

作者： ZHANG Lijuan JIANG Lanqi ZHANG Xuezhen Key Laboratory of Remote Sensing Monitoring of Geographic Environment Harbin Normal University Harbin 150025 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Jiangsu Collaborative Innovation Center for Climate Change Nanjing 210093 China

We initially estimated the cropland area at county level using local historical documents for the Songnen Plain （SNP） in the 1910s and 1930s. We then allocated this cropland area to grid cells with a size of 1 km ×1 km, using a range of cultivation possibilities from high to low; this was based on topography and minimum distances to rivers, settlements, and traffic lines. Cropland areas for the 1950s were obtained from the land Use Map of Northeast China, and map vectorization was performed with ArcGIS technology. Cropland areas for the 1970s, 1980s, 1990s, 2000s, and 2010s were retrieved from landsat images. We found that the cropland areas were 4.92 ×10^4 km^2 and 7.60 ×10^4 km^2, accounting for 22.8% and 35.2% of the total area of the SNP in the 1910s and 1930s, respectively, which increased to 13.14 × 10^4 km^2, accounting for 60.9% in the 2010s. The cropland increased at a rate of 1.18 ×10^4 km^2 per decade from the 1910s to 1970s while it was merely 0.285 ×10^4 km^2 per decade from the 1970s to 2010s. From the 1910s to 1930s, new cultivation mainly occurred in the central SNP while, from the 1930s to 1970s, it was mainly over the western and northern parts. This spatially explicit reconstruction could be offered as primary data for studying the effects of changes in human-induced land cover based on climate change over the last century.

关键词： land use/cover changes agricultural development historical documents gridding data

来源：评论

学校读者我要写书评

暂无评论

Reconstruction of Lu-level cropland areas in the Northern Song Dynasty （AD976-1078）

引用

Journal of Geographical Sciences 2017年第5期27卷 606-618页

作者：何凡能李美娇李士成 Key Laboratory of Land Surface Pattern and Simulation institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China School of Public Administration China University of Geosciences Wuhan 430074 China

Based on data on taxed-cropland area and on the number of households in historical documents, a probabilistic model of cropland distribution and a cropland area allocation model were designed and validated. Cropland areas for the years AD976, 997, 1066, and 1078 were estimated at the level of Lu（an administrative region of the Northern Song Dynasty）. The results indicated that（1） the cropland area of the whole study region for AD976, 997, 1066, and 1078 was about 468.27 million mu（a Chinese unit of area, with1 mu=666.7m2）, 495.53 million mu, 697.65 million mu, and 731.94 million mu, respectively. The fractional cropland area（FCA） increased from 10.7% to 16.8%, and the per capita cropland area decreased from 15.7 mu to 8.4 mu.（2） With regard to the cropland spatial pattern, the FCA of the southeast, north, and southwest regions of the Northern Song territory increased by 12.0%, 5.2%, and 1.2%, respectively. The FCA of some regions in the Yangtze River Plain increased to greater than 40%, and the FCA of the North China Plain increased to greater than 20%. However, the FCA of the southwest region（except for the Chengdu Plain） in the Northern Song territory was less than 6%.（3） There were 84.2% Lus whose absolute relative error was smaller than 20% in the mid Northern Song Dynasty. The validation results indicate that our models are reasonable and that the results of reconstruction are credible.

关键词： land use/cover change cropland area Lu-level reconstruction spatial–temporal characteristics Northern Song Dynasty

来源：评论

学校读者我要写书评

暂无评论

Examining the influence of the implementation of Major Function-oriented Zones on built-up area expansion in China

引用

Journal of Geographical Sciences 2017年第6期27卷 643-660页

作者： LIU Wenchao LIU Jiyuan KUANG Wenhui NING Jia Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natura Resources Research CAS Beijing 100101 China College of Urban and Environment Science Tianjin Normal University Tianjin 300387 China University of Chinese Academy of Sciences Beijing 100049 China

China had implemented the national strategies for Major Function-oriented Zones （MFOZs） to realize the goal of national sustainable development since 2010. This study analyzed and compared spatio-temporal characteristics and differences in built-up area for China＇s MFOZs using a China＇ s land Use Database （CLUD） derived from high-resolution remotely sensed images in the periods of 2000-2010 and 2010-2013. To sum up：（1） The percentage of built-up area in each of the MFOZs was significantly different, revealing the gradient feature of national land development based on the distribution of the main functions. （2） Annual growth in built-up area in optimal development zones （ODZs） decreased signifi- cantly during 2010-2013 compared with the period 2000-2010, while annual growth in built-up area in key development zones （KDZs）, agricultural production zones （APZs） and key ecological function zones （KEFZs） increased significantly. （3） In ODZs, the average annual increase in built-up area in the Yangtze River Delta region was significantly higher than in other regions; the average area increase and rate of increase of built-up area in KDZs was faster in the western region than in other regions; average annual area growth of built-up area in APZs in the northeast, central and western regions was twice as high as the previous decade on average; the annual rate of change and increase in the dynamic degree of built-up area were most notable in KEFZs in the central region. （4） The spatial pattern and charac- teristics of built-up area expansions in the period 2010-2013 reflected the gradient feature of the plan for MFOZs. But the rate of increase locally in built-up area in ODZs, APZs and KEFZs is fast, so the effective measures must be adopted in the implementation of national and regional policies. The conclusions indicated these methods and results were meaningful for future regulation strategies in optimizing national land development in China.

关键词： Major Function-oriented Zones satellite remote sensing land use change development of urban andtown built-up area China

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：