中国北方未来50年土地利用变化模拟

1 IntroductionLand use m odelling is a useful tool to analyze the land use cause, process and result, torecognize the im pact of land use system change on ecological environm ent,and to support theland use planning and policy (IIA SA ,1998;Costanza etal.,…     

Land cover changes in the rural-urban interaction of Xi＇an region using Landsat TM/ETM data

Landsat ETM/TM data and an artificial neural network （ANN） were applied to analyse the expansion of the city of Xi＇an and land use/cover change of its surrounding area between 2000 and 2003. Supervised classification and normalized difference barren index （NDBI） were used respectively to retrieve its urban boundary. Results showed that the urban area increased by an annual rate of 12.3%, with area expansion from 253.37 km^2 in 2000 to 358.60 km^2 in 2003. Large areas of farmland in the north and southwest were converted into urban construction land. The land use/cover changes of Xi＇an were mainly caused by fast development of urban economy, population immigration from countryside, great development of infrastructure such as transportation, and huge demands for urban market. In addition, affected by the government policy of “returning farmland to woodland”, some farmland was converted into economic woodland, such as Chinese goosebeerv garden, vineyard etc.     

Land use change and its ecological effect in Qian＇an County of Jilin Province

Based on GIS and statistical methods, with the help of searching historical literatures and calculating the landscape indices, the land use changes of Qian‘an County in both spatial and temporal aspects from 1945 to 1996 has been analyzed in this paper. And the driving forces of land use changes and their ecological effects are discussed too. The main findings of this study are as follows: (1) Land use changed greatly in Qian‘an during 1945-1996, characterized by a decrease in grassland, wetland and water bodies, and an increase in cultivated land, saline-alkali land, and the land for housing and other construction purposes. Grassland decreased by 175,828.66 ha, and cultivated land increased by 102,137.23 ha over the half century. Accordingly, the main landscape type changed from a steppe landscape to a managed agricultural ecosystem. (2) Results of correlation analysis show that the land use change in the study area was mainly driven by the socioeconomic factors. (3) The ecological effects of land use change in the area are characterized by serious salinization, degression of soil fertility and the weakening, of landscaoe suitability.     

Markedness Features of Online Chatters’ English Nicknames In the Cyber Communicative Activities

With the development of internet,the use of chat rooms is one of the most popular cyber communicative activities.As a commnication window,Cyber nicknames are very pivotal to find desirable chatting partners from such a huge populaiton.This paper takes on chatters’English cyber nicknames as the main object of study,investigating markedness features and communicative meaning of English cyber nicknames from the perspective of markedness theory.     

Land use change in Bohai Rim: a spatial-temporal analysis

Land use change is one of the important aspects of global change[1-3]. The Bohai Rim is a hot spot of economic development in China, where land use changes remarkably. Analyzing land use change in this area is significant to the research of global change and regional sustainable land use. Although there has been much work undertaken on regional land use change in China, it was mainly on urban land use change[4-11], and few researches integrated remote sensing and GIS method. Based on data f…     

宁夏北部地区土地覆盖模式及其发展潜力

With the objectives to acquire the fundamental data of the territorial resource,understand the impacts of human activities on the lan use and cover patterns and evaluate the potential of the future exploitation,and intensive land cover classification with and accuracy of 93?has been completed for North Ningxia by remote sensin technique based on the adoption of a combination method composed of texture training,maximum likelihood classification and post-processing such as re-allocation and aggregation.This classification result was incorporated with the contemporaneous socio-economic and meteorological data for cross-sectional regression modelling to reveal the spatial determinants of the land cover patterns and understand the human-environmental relationships.A tentative evaluation on the potential of soil exploitation in the near future was carried out in combination with our land use and cover change detection results aiming at supplying some useful references for the central and local governments in their sustainable land use planning.     

21世纪初中国土地利用变化的空间格局与驱动力

Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the "Grain for Green" policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of "Western Development", "Revitalization of Northeast", coupled with rapidly economic development during this period.     

1980年以来中国农地利用变化的区域差异

The study of land use change and its driving mechanism has become the focus since the research of land use/land cover change (LUCC) became one of the important areas of Global Environmental Change (GEC) researches in the 1990s (Turner, 1994). Scholars mai…     

Characteristics of soil water repellency after sand dune stabilization in the Tengger Desert

Soil water repellency (SWR) is one of the most important physical properties of soils found all over the world, and it may have significant effects on the eco-hydrological processes of land ecosystems. In this study, the Capillary Rise Method was used to measure the SWR in the artificial vegetation area in Shapotou, located in the southeast area of the Tengger Desert, Ningxia Province of western China. The variation of the soil water repellency among different minor topographies, different depths and different particle sizes was analyzed. The results of the study indicate that the SWR shows distinct changes with vegetation restoration, and it increases with an increase in the period of dune stabilization. In the same vegetation area, the SWR of soils in inter-dune depressions or windward slopes is slightly greater than that in crest or leeward slopes. The SWR of 0–3 cm topsoil is significantly greater than that in the 3–6 cm soil layer. The SWR decreases with an increase in grain size and the differences among the SWRs of different sieved soil fractions are found to be significant. There is also a significantly positive correlation between the SWR and the proportion of soils with grain sizes of 0–0.05, 0.05–0.01 and 0.01–0.15 mm, and a significantly negative correlation between the SWR and the propotion of soils with grain sizes exceeding 0.15 mm. The increase of SWR in revegetation areas may depend on the continuous depositing of atmospheric dust on the stabilized dune surface as well as the formation of biological soil crusts, especially on the formation of algal and lichen crusts. Enhanced SWR influences the effectiveness of water use of sand plants inhabiting the sand dunes.     

黄淮海平原农区土地利用转型及其动力机制（英文）

Land use transition refers to changes in land use morphology, including dominant morphology and recessive morphology, of a particular region over a period of time driven by various factors. Recently, issues related to land use transition in China have attracted interest among a wide variety of researchers as well as government officials. This paper examines the patterns of land use transition and their dynamic mechanism in the Huang-Huai-Hai Plain during 2000–2010. First, the spatio-temporal patterns of land use transition, their characteristics and the laws governing them were analyzed. Second, based on the established conceptual framework for analyzing the dynamic mechanism of land use transition, a spatial econometric regression analysis method was used to analyze the dynamic mechanism of the five types of major land use transition in the Huang-Huai-Hai Plain at the county level. Land use pattern changes in the study area were characterized by an increase in construction land, water body and forested land, along with a decrease in farmland, unused land and grassland. The changes during 2000–2005 were much more significant than those during 2005–2010. In terms of factors affecting land use transitions, natural factors form the basis, and they have long-term effects. Socio-economic factors such as population and GDP, however, tend to determine the direction, structure, size and layout of land use transition over shorter time periods. Land law and policy factors play a mandatory guiding and restraining role in land use transitions, so as to improve the overall efficiency of land use. Land resource engineering is also an important tool to control land use transitions. In general, the five types of major land use transition were the result of the combined action of various physical, social and economic factors, of which traffic condition and location condition had the most significant effects, i.e. they were the common factors in all land use transitions. Understanding the spatio-temporal process of land use transitions and their dynamic mechanisms is an important foundation for utilizing land resources, protecting regional ecological environment and promoting sustainable regional socio-economic development.     

Land use change and its corresponding ecological responses: a review

This paper reviews the research on land use change and its corresponding ecological responses. Patterns of land use changes in spatio-temporal level are produced by the interaction of biophysical and socio-economic processes. Nowadays, the studies derived from different socioeconomic conditions and scales show that at short-term scale, human activities, rather than natural forces, have become a major force in shaping the environment, while biophysical factors control the trends and processes of land use change under the macro environmental background. Providing a scientific understanding of the process of land use change, the impacts of different land use decisions, and the ways that decisions are affected by a changing environment and increasing ecological variability are the priority areas for research: (1) explanation of scale dependency of drivers of land use change; (2) quantification of driving factors of land use change; (3) incorporation of biophysical feedbacks in land use change models; and (4) underlying processes and mechanisms of ecological impacts of land use change.     

农业物候动态对地表生物物理过程及气候的反馈研究进展

地表过程对全球变化的响应和反馈是地球系统科学研究的核心课题之一,目前的研究多关注全球变化对地表过程的影响,而地表动态过程对地表生物物理过程及气候的反馈研究较少。系统认识地表物候动态对生物物理过程及气候的反馈对深化地球系统科学研究有着重要的意义。本文从农业物候动态的事实、农业物候动态在陆面过程模型中的参数化表达、农业物候动态对地表生物物理过程及气候的反馈等方面进行综述,发现在气候变化和管理措施影响下,以种植期和灌浆期为代表的农业物候期发生了显著的规律性变化;耦合农业物候动态,改善了模型对地表动态过程、生物物理过程和大气过程的数字化表达;农业物候变化对地表净辐射、潜热、感热、反照率和气温、降水、环流等过程产生了影响,并表现出以地表能量分配为主的气候反馈机理。针对农业物候动态对地表生物物理过程及气候效应的时空重要性,需要继续开展以下方面的工作：① 加强全球变化对地表物候动态的影响及其反馈的综合研究;② 不同光谱波段地表反射率与农业物候动态的关系研究;③ 农业物候动态引起的作物生理学特征变化在地表生物物理过程中的贡献;④ 重视不同气候区物候动态对气候反馈效应的差异。     

LUCC驱动力模型研究综述

驱动力研究是土地利用变化研究中的核心问题。土地利用变化驱动力模型是分析土地利用变化原因和结果的有力工具，模型通过情景分析可为土地利用规划与决策提供依据。基于不同理论的驱动力研究方法很多，论文选取了几种国内外应用较多的LUCC驱动力模型进行综述，分析了每个模型的优缺点及适用范围，最后得出结论：1) 基于过程的动态模型更适于研究复杂的土地利用系统。2) 基于经验的统计模型能弥补基于过程的动态模型的不足。3) 基于不同学科背景的模型进一步集成将是LUCC驱动力模型未来的发展趋势。     

土地利用与土地覆盖变化对气候影响的国别对比（英文）

Land use and land cover change(LULCC) strongly influence regional and global climate by combining both biochemical and biophysical processes. However, the biophysical process was often ignored, which may offset the biogeochemical effects, so measures to address climate change could not reach the target. Thus, the biophysical influence of LULCC is critical for understanding observed climate changes in the past and potential scenarios in the future. Therefore, it is necessary to identify the mechanisms and effects of large-scale LULCC on climate change through changing the underlying surface, and thus the energy balance. The key scientific issues on understanding the impacts of human activities on global climate that must be addressed including:(1) what are the basic scientific facts of spatial and temporal variations of LULCC in China and comparative countries?(2) How to understand the coupling driving mechanisms of human activities and climate change on the LULCC and then to forecasting the future scenarios?(3) What are the scientific mechanisms of LULCC impacts on biophysical processes of land surface, and then the climate?(4) How to estimate the contributions of LULCC to climate change by affecting biophysical processes of land surface? By international comparison, the impacts of LULCC on climate change at the local, regional and global scales were revealed and evaluated. It can provide theoretical basis for the global change, and have great significance to mitigate and adapt to global climate changes.     

The climatic impacts of land use and land cover change compared among countries

Land use and land cover change (LULCC) strongly influence regional and global climate by combining both biochemical and biophysical processes. However, the biophysical process was often ignored, which may offset the biogeochemical effects, so measures to address climate change could not reach the target. Thus, the biophysical influence of LULCC is critical for understanding observed climate changes in the past and potential scenarios in the future. Therefore, it is necessary to identify the mechanisms and effects of large-scale LULCC on climate change through changing the underlying surface, and thus the energy balance. The key scientific issues on understanding the impacts of human activities on global climate that must be addressed including: (1) what are the basic scientific facts of spatial and temporal variations of LULCC in China and comparative countries? (2) How to understand the coupling driving mechanisms of human activities and climate change on the LULCC and then to forecasting the future scenarios? (3) What are the scientific mechanisms of LULCC impacts on biophysical processes of land surface, and then the climate? (4) How to estimate the contributions of LULCC to climate change by affecting biophysical processes of land surface? By international comparison, the impacts of LULCC on climate change at the local, regional and global scales were revealed and evaluated. It can provide theoretical basis for the global change, and have great significance to mitigate and adapt to global climate changes.     

西藏农牧区农户土地决策与土地覆被变化研究

调查农户土地决策，均质化处理农户决策因子，形成土地决策空间图；制作土地覆被图和农户土地决策空间图，通过图像叠加处理，来分析土地覆被变化与农户土地决策度政策因子间的空间联系。西藏农牧区案例研究结果表明：农户土地决策决定了土地覆被变化方向，政策因子起修正作用；农户土地决策与土地覆被在空间上和属性上能互相体现；农牧区政策的制定应立足于农户土地决策，在满足农户追求最大经济效益的基础上引导农户顾及生态环境建设；农户土地决策、社会经济发展政策与土地覆被在空闻上能互相体现，可通过观察土地覆被变化来监测农户土地决策及政策因子效果。     

CLUE-S模型应用进展与改进研究

土地利用变化是景观生态学重要的研究领域,通过模型模拟土地利用变化趋势是该领域的主要研究内容之一。CLUE-S模型可以全面考虑自然和人文因子,通过迭代方法综合空间分析和非空间分析,较好地模拟小尺度范围内土地利用变化情景,具有综合性、开放性、空间性、竞争效率性等特点,已经在国内外多个地区的土地利用变化研究中得到广泛应用,形...     

基于SD和CLUE-S模型的张掖市甘州区土地利用情景分析

近年来,学者们基于不同研究需要开发了很多土地利用变化/覆盖(LUCC)模型.但迄今没有一个单独的模型可在不同时空尺度上揭示所有土地利用变化的关键过程.本文尝试开发一种集成SD模型与CLUE-S模型的建模方法,用以弥补已有LUCC模型缺陷,并将其应用于张掖市甘州区的土地利用情景分析中,得到的LUCC模拟结果可为该区土地利...     

湿地景观格局变化研究进展

湿地是自然界最富生物多样性的生态景观,具有重要的生态功能。湿地景观格局是各种生态过程综合作用的结果,具有高度的景观异质性,对景观的功能和过程有着显著的影响。湿地生态系统是世界上受威胁最为严重的生态系统之一,在自然因素和人类活动的影响下发生了大面积的转化或丧失。本文从湿地景观格局研究方法、面积变化、景观类型转化、驱动力以及动态模型、湿地景观格局指数以及湿地景观格局与气候变化之间的关系等方面综述了湿地景观格局变化的研究进展,指出湿地景观格局变化及其生态效应和高原湿地景观格局变化与气候变化之间的关系是未来研究的重点领域。     

土地质量的空间变异与尺度效应研究进展

土地质量能体现自然因素与人类活动对土地的影响，直接关系着环境改善与土地持续利用。20世纪80年代以来，人口增长与经济发展对土地资源的压力越来越大，并导致了不同程度的土地质量退化，人们越来越关注土地质量的提高及其管理。深入认识不同尺度土地质量空间变化与发展对土地质量的提高与管理具有重要意义。本文首先介绍了土地质量和尺度的概念及其特征，阐述了空间变异的研究方法，重点综述了土地质量的空间变异与尺度效应研究进展，并提出了土地质量空间变异及其相关研究的发展趋势，以期对我国土地质量的研究和实现土地资源可持续利用有所启迪。