20世纪80年代末以来中国土地利用变化的基本特征与空间格局

土地利用/土地覆被变化（LUCC）是人类活动与自然环境相互作用最直接的表现形式,本文采用相同空间分辨率的卫星遥感信息源和相同的技术方法,对中国1980 年代末到2010 年土地利用变化数据进行定期更新。在此基础上,提出并发展土地利用动态区划的方法,研究土地利用变化的空间格局与时空特征。我们发现：1990-2010 年的20 年间,中国土地利用变化表现出明显的时空差异。“南减北增,总量基本持衡,新增耕地的重心逐步由东北向西北移动”是耕地变化的基本特征;“扩展提速,东部为重心,向中西部蔓延”是城乡建设用地变化的基本特征;“林地前减后增,荒漠前增后减,草地持续减少”是非人工土地利用类型变化的主要特征。20 世纪末与21 世纪初两个10 年相比,中国土地利用变化空间格局出现了一些新特征,原有的13 个土地利用变化区划单元演变为15 个单元,且部分区划单元边界发生变化。主要变化格局特征为黄淮海地区、东南部沿海地区、长江中游地区和四川盆地城镇工矿用地呈现明显的加速扩张态势;北方地区耕地开垦重心由东北地区和内蒙古东部转向西北绿洲农业区;东北地区旱作耕地持续转变为水田;内蒙古农牧交错带南部、黄土高原和西南山地退耕还林还草效果初显。近20 年间,尽管气候变化对北方地区的耕地变化有一定的影响,但政策调控和经济驱动仍然是导致我国土地利用变化及其时空差异的主要原因。2000 年后的第一个10 年,土地利用格局变化的人为驱动因素已由单向国土开发为主,转变为开发与保护并重。在空间格局变化的分析方法方面,应用“动态区划法”开展世纪之交两个10 年中国LUCC空间格局变化的分析,有效揭示了20 年来中国LUCC“格局的变化过程”,即动态区划边界的推移、区划单元内部特征的变化与单元的消长等;以及“变化过程的格局”,即土地利用变化过程与特征的分阶段区域差异,清晰刻画了LUCC动态区划中区划单元的消长,单元边界的变动,以及前后10 年的变化强度特征,揭示了土地利用“格局”与“过程”之间的交替转化规律,以及不同类型和区域的变化原因,证明了该分析方法的有效性。     

基于主体功能区规划的中国城乡建设用地扩张时空特征遥感分析

21世纪以来,随着中国社会经济的快速发展,城乡建设用地不断扩张,对社会经济和生态环境造成了一系列影响.为了国家可持续发展目标的实现,必须对国土开发空间布局做出科学的规划.为此,一些学者开展了国家主体功能区规划方案研究,其研究成果支持了国家主体功能区规划的制定,该规划于2010年底颁布实施.为分析各类主体功能区在规划颁布前后城乡建设用地变化的特征,评估规划对区域开发的指导作用,及时发现规划实施中的问题,有必要采取有效手段对不同类型主体功能区的国土开发活动进行监测和评估.为此,本研究团队在已完成的2000年和2010年两期全国土地利用变化数据库的基础上,更新了2013年全国土地利用数据库,生成分期的城乡建设用地空间数据集;并对国家尺度各类主体功能区,以及东部,中部,西部,东北4大区域在主体功能区规划颁布前10年间(2000-2010年)和后3年内(2010-2013年)城乡建设用地扩张特征与差异进行了对比分析.结果表明:① 总体而言,2013年优化开发区,重点开发区,农产品主产区和重点生态功能区城乡建设用地在该类主体功能区国土面积中的占比明显不同,体现了国土开发按照不同主体功能布局的梯级特征.② 与2000-2010年相比,2010-2013年优化开发区城乡建设用地年增长率明显降低,重点开发区,农产品主产区和重点生态功能区建设用地年增长率均大幅增加;其中重点开发区和农产品主产区的城乡建设用地年均扩张面积已经超过了优化开发区;重点生态功能区城乡建设用地年均扩张面积和动态度仍处于最低的水平.③ 在区域尺度,优化开发区中,长江三角洲地区建设用地年均增量明显高于其他优化开发区;重点开发区中,西部地区在年增加面积和增加速率两方面均高于其他区域;农产品主产区中,东部,中部和西部地区内城乡建设用地年增加面积均超过前10年的2倍,西部地区的年增加速率更是达到前10年的3倍以上;重点生态功能区中,中部地区城乡建设用地的年变化率和动态度的增长均最为显著.④ 2010-2013年中国城乡建设用地扩张的空间格局和变化特征,在总体上体现了主体功能区规划的梯级开发特征.但是,局部优化开发区,农产品主产区和重点生态功能区建设用地的扩张速度过快,必须切实加强空间管控.研究表明,采用空间格局变化的分析方法,开展主体功能区规划颁布前后两个时期城乡建设用地扩张特征与分阶段区域差异的分析,清晰刻画出不同功能区和不同地区建设用地变化规律及其与主体功能区规划的契合程度,证明了该分析方法的有效性,可据此为未来国土开发空间格局的优化和城乡建设发展提供科学依据.     

中国土地利用时空特征分析

在遥感技术与GIS技术的支持下，对中国近5年来土地利用的时间动态特征和空间动态特征进行了定量分析。具体表现为通过数学建模，利用土地利用动态度模型、土地利用程度模型、垦殖指数模型等对土地利用时空特征进行了分析。研究结果表明：5年间中国土地利用类型发生变化比较大的区域主要分布在东部和北部地区，特别是东北部地区土地利用类型变化比较剧烈，而西部变化相对缓慢；土地利用各类型中面积增加的有耕地、水域、建设用地和未利用地，而林地、草地面积减少；耕地增加的区域位于东北部地区，特别是黑龙江省耕地面积增加最多；林草地以及未利用地的面积变化主要发生在新疆、内蒙和黑龙江等地区，其它地区变化幅度相对较小。     

1956-2000年中国潜在蒸散量时空变化特征

1 Introduction Evaporation is one of the important components in the water and heat balances. The transpiration of vegetation and evaporation from soil are collectively called evapotranspiration. Potential evapotranspiration is not only the theoretical li…     

中国土地利用效益的时空特征研究

基于经济、社会、生态三维视角构建土地利用效益评价指标体系,运用灰色关联方法测度2004—2014年中国土地利用效益水平,并借助于Arc GIS空间分析技术分析其空间异质性及空间演变格局。从时序特征来看,2004—2014年全国土地利用效益波动性提升。从空间特征来看,中国土地利用效益的空间格局存在差异性,但差异日渐缩小;土地利用效益的增减空间分布不均,随着时间的推移,土地利用效益提升省份增加的幅度越来越大,土地利用效益降低省份的下降幅度越来越小;中国土地利用效益空间集聚特征明显,热点主要分布在内蒙古、辽宁和西藏,冷点主要分布在东南沿海地区;土地利用效益的变化也表现出集聚特征,东南沿海与西部地区为中国土地利用效益变化最强烈的集聚区,其土地利用效益变化呈互逆发展态势;中国土地利用效益变化具有明显的政策导向性。     

2015—2020年中国土地利用变化遥感制图及时空特征分析

持续地开展国家尺度土地利用/覆盖变化遥感监测对于新时代国土空间规划和“美丽中国”蓝图绘制具有重要的科学价值。本文采用Landsat 8 OLI、GF-2等卫星遥感数据,融合遥感大数据云计算和专家知识辅助人机交互解译方法,研发了中国土地利用变化（2015—2020年）和2020年土地利用现状矢量数据（CLUD 2020）,建立了完整的30 a（20世纪80年代末—2020年）每隔5 a的30 m分辨率中国土地利用动态数据库。基于CLUD 2020数据,从全国和区域两个尺度揭示了2015—2020年中国土地利用变化的总体规律、区域分异和主要特征。研究表明：将遥感大数据云计算生成的30 m分辨率植被覆盖变化和地表类型变化检测信息融入到人机交互遥感解译方法,可有效地提高大范围土地利用变化遥感制图的效率和变化图斑辨识的准确性;精度评价表明,CLUD 2020一级类型制图的综合精度达95%。总体上,全国范围内国土空间开发强度与2010—2015年比较进入相对稳定状态。期间全国耕地面积仍保持减少态势,空间分异特征为耕地南减北增,东北松嫩平原及其与三江平原交界区大规模的旱地向水田转移,西北新疆南部开垦和北部退耕/撂荒并存;全国城乡建设用地持续增加,空间分异特征表现为由以往的沿海地区和超大、大城市集聚转向中西部地区的大中小城镇周边蔓延为主。全国范围的林草自然生态用地面积持续减少,但强度与2010—2015年比较有所下降;受气候变化的持续影响,青藏高原地区的河流湖泊等水域面积显著增加。以上土地利用变化格局与“十三五”期间国家高质量发展、生态文明建设宏观战略和气候变化的影响密切相关。     

广州市土地利用时空变化研究

土地利用变化包括土地数量变化、质量变化和空间变化.土地利用空间变化作为土地利用变化研究的重要内容,对了解一个地区土地利用变化规律有着深刻意义.广州市属于我国发达地区,研究广州市土地利用空间变化有助于加深对我国发达地区的土地利用变化情况的了解.利用1990,2000年广州市土地利用数据,并结合ArcGis 的分析功能,分析了广州市10年间的土地利用空间变化状况,发现广州市土地利用变化有一定方向性,并且不同辖区的土地利用变化类型不同.10年间全市和各辖区的土地利用程度和信息熵都有所增加.但除了番禺,各辖区的土地利用类型组合却保持不变.     

南京市热岛效应变化时空特征及其与土地利用变化的关系

利用遥感数据和气象统计数据分析自1985年以来南京市热岛效应变化的时空特征及其与土地利用变化的关系。结果表明:自1985年以来,南京市热岛效应强度和范围在增长。南京市的年均温逐年上升,与郊区六合县的温差呈上升趋势;南京市建成区内4级热岛效应面积增加了107.88km²。热岛效应增长在空间上存在差异,大厂>雨花台>市辖区>栖霞>浦口>江宁。南京市土地利用变化的结果使得热岛效应空间分布更广泛,城镇居民点及工矿用地利用强度变化最大的地方即城市热岛效应增加最多的地方,两者在空间上具有很好的吻合;而和城镇居民点及工矿用地的扩展规模没有很好的空间相关性。     

20世纪90年代中国土地利用变化时空特征及其成因分析

在土地利用变化时空信息平台的支持下,本文对我国20世纪80年代末到90年代末的土地利用变化过程进行了全面分析,揭示了我国10年来土地利用变化的时空规律,分析了这些规律形成的主要政策、经济和自然成因。研究表明,20世纪90年代,全国耕地总面积呈北增南减、总量增加的趋势,增量主要来自对北方草地和林地的开垦。林业用地面积呈现总体减少的趋势,减少的林地主要分布于传统林区,南方水热充沛区造林效果明显。中国城乡建设用地整体上表现为持续扩张的态势。90年代后5年总体增速减缓,西部增速加快。20世纪90年代我国的土地利用变化表现出明显的时空差异,政策调控和经济驱动是导致土地利用变化及其时空差异的主要原因。据此,本文提出在今后的全国土地利用规划中,应充分考虑我国现代土地利用变化的区域分异规律。同时,在生态环境恢复与建设规划中也应强调自然地理地带的针对性,同时要改变传统的资源规划与管理思路,在基础设施日益完备的条件下,最大程度地发挥跨区域土地资源优化配置的综合优势     

2002-2010年长江流域GRACE水储量时空变化特征

利用高斯平滑滤波对2002年4月-2010年12月逐月GRACE卫星的时变重力场数据反演得到长江流域大尺度陆地水储量变化,对其时空变化进行研究,并将结果与全球陆面同化数据(GLDAS)模拟结果进行比较。其结论为:根据GRACE数据反演与GGLDAS模拟得到的水储量结果在大多数区域变化趋势相同,两者具有一致性,相关性达到0.89(P<0.05)。GRACE水储量研究结果表明:①2002-2010年长江流域水储量呈增加趋势,平均增长速率为0.43mm/月,相当于约95.04亿m³/年。长江上游增长速率为0.53mm/月,相当于约67.13亿m³/年;中游增长速率为0.51mm/月,相当于25.73亿m³/年;下游增长速率为0.36mm/月,相当于9.14亿m³/年。近9年长江流域水储量共增加约855.33亿m³。②从多年平均水储量空间分布来看,长江流域冬季月份(12、1、2、3月)水储量处于亏损状态,7-9月水储量处于盈余状态,4-6月下游至上游地区由亏损向盈余状态过渡,而10-11月则从上游至下游地区由盈余向亏损状态过渡。③全流域、上游及中游水储量逐月增长速率最大值出现在9月,分别为1.01cm/a、1.37cm/a、1.05cm/a;而下游地区则出现在7月,增长速率为1.62cm/a。     

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

Spatiotemporal patterns and characteristics of land-use change in China during 2010–2015

Land use/cover change is an important theme on the impacts of human activities on the earth systems and global environmental change. National land-use changes of China during 2010–2015 were acquired by the digital interpretation method using the high-resolution remotely sensed images, e.g. the Landsat 8 OLI, GF-2 remote sensing images. The spatiotemporal characteristics of land-use changes across China during 2010–2015 were revealed by the indexes of dynamic degree model, annual land-use changes ratio etc. The results indicated that the built-up land increased by 24.6×10³ km² while the cropland decreased by 4.9×10³ km², and the total area of woodland and grassland decreased by 16.4×10³ km². The spatial pattern of land-use changes in China during 2010–2015 was concordant with that of the period 2000–2010. Specially, new characteristics of land-use changes emerged in different regions of China in 2010–2015. The built-up land in eastern China expanded continually, and the total area of cropland decreased, both at decreasing rates. The rates of built-up land expansion and cropland shrinkage were accelerated in central China. The rates of built-up land expansion and cropland growth increased in western China, while the decreasing rate of woodland and grassland accelerated. In northeastern China, built-up land expansion slowed continually, and cropland area increased slightly accompanied by the conversions between paddy land and dry land. Besides, woodland and grassland area decreased in northeastern China. The characteristics of land-use changes in eastern China were essentially consistent with the spatial govern and control requirements of the optimal development zones and key development zones according to the Major Function-oriented Zones Planning implemented during the 12th Five-Year Plan (2011–2015). It was a serious challenge for the central government of China to effectively protect the reasonable layout of land use types dominated with the key ecological function zones and agricultural production zones in central and western China. Furthermore, the local governments should take effective measures to strengthen the management of territorial development in future.     

Spatiotemporal characteristics,patterns, and caus-es of land-use changes in China since the late 1980s

Land-use/land-cover changes (LUCCs) have links to both human and nature interactions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year intervals from the late 1980s to 2010,with standard procedures based on Landsat TM\ETM+ images. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics,differences,and causes of land-use changes at a national scale were then examined. The main findings are summarized as follows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change decreased in the south and increased in the north,but the total area remained almost unchanged. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly,were mainly distributed in the east,and gradually spread out to central and western China. Woodland decreased first,and then increased,but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region,the southeastern coastal areas,the midstream area of the Yangtze River,and the Sichuan Basin;(2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China;(3) continuous transformation from rain-fed farmlands in northeast China to paddy fields;and (4) effectiveness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia,the Loess Plateau,and southwestern mountainous areas. In the last two decades,although climate change in the north affected the change in cropland,policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century,the anthropogenic factors that drove variations in land-use patterns have shifted the emphasis from one-way land development to both development and conservation.The "dynamic regionalization method" was used to analyze changes in the spatial patterns of zoning boundaries,the internal characteristics of zones,and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning,variations in unit boundaries,and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the causes for changes in different types and different regions of land use were explored.     

Spatiotemporal characteristics,patterns and causes of land use changes in China since the late 1980s简

Land-use/land-cover changes （LUCCs） have links to both human and nature inter- actions. China＇s Land-Use/cover Datasets （CLUDs） were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM／ETM＋ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes （LUCs） across China indicated a significant variation in spatial and temporal characteristics in the last 20 years （1990-2010）. The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included （1） an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; （2） shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; （3） continuous transformation from rain-fed farmlands in northeast China to paddy fields; and （4） effective- ness of the ＂Grain for Green＂ project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change in the north affected the change in cropland, policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century, the anthropogenic factors that drove variations in land-use pat- terns have shifted the emphasis from one-way land development to both development and conservation. The ＂dynamic regionalization method＂ was used to analyze changes in the spatial patterns of zoning boundaries, the internal characteristics of zones, and the growth and decrease of units. The results revealed ＂the pattern of the change process,＂ namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning, variations in unit boundaries, and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the ＂pattern＂ and ＂process＂ of land use and the causes for changes in different types and different regions of land use were explored.     

城市轨道交通对土地利用变化的时空效应

定量分析轨道交通对城市内部精细土地利用复杂变化影响的时空效应,对于预测未来新建站点对土地利用的影响以及规划方案的调整与优化具有重要的指导意义。本文提出结合历史高分遥感影像与POI数据获取多时间节点精细土地利用信息的方法,并以广州市二号和八号地铁线为例,结合逐步回归模型与站点用地功能分类,从时间和空间两个维度定量研究地铁对土地利用转变的复杂影响过程与空间差异规律。结果表明,轨道交通促使站点周边低密度居住用地向商业用地、高密度居住用地等高效益土地利用方式的转变;轨道交通在规划、建设、运营不同阶段对于周边土地利用的影响呈现显著的差异规律;地铁站点对土地利用变化影响规律具有明显的空间异质性特征,与站点在城市里的位置以及站点周边的土地利用有关,对城市中心区域的影响较小,对郊区的影响主要与可用的非建设用地面积相关,而工业用地对土地利用变化具有限制作用;轨道交通还带来用地功能和性质的转变,这样的转变大多发生在地铁站点开通运营的时间点。     

中国近30年气候要素时空变化特征

利用1971~2000年中国603个气象站点逐日平均温度和降水量数据,借助ArcGIS空间分析工具,采用自组织特征映射模型(SOFM),对中国气候变化的时空特征进行分析。研究结果表明:近30年中国气候变化的总体特征以增温为主,增温增湿的地区面积最为广大;季节变化构型也以增温增湿为主,秋季略有异常;从年代际变化来看,1971~1980年间,中国的气候以降温为主,而从1981年开始的20年间,全国的气候变化转为增温占主导。SOFM网络分类结果可以描述为缓增温少降水、剧增温平降水、缓增温缓降水和剧增温剧降水等四种类型。     

2001-2010年中国地表比辐射率的时空变化(英文)

Land surface emissivity is one of the important parameters in temperature inversion from thermal infrared remote sensing. Using MOD11C3 of Terra-MODIS L3 level products, spatio-temporal data sets of land surface emissivity in China for 10 years from 2001 to 2010 are obtained. The results show that the land surface emissivity in the northwest desert region is the lowest in China, with little seasonal variations. In contrast, there are significant seasonal variations in land surface emissivity in northeast China and northern Xinjiang, the Qing-hai-Tibet Plateau, the Yangtze River Valley and the eastern and southern China. In winter, the land surface emissivity in the northeast China and northern Xinjiang is relatively high. The land surface emissivity of the Qinghai-Tibet Plateau region is maintained at low value from November to March, while it becomes higher in other months. The land surface emissivity of the Yangtze River Valley, eastern and southern China, and Sichuan Basin varies from July to October, and peaks in August. Land surface emissivity values could be divided into five levels: low emissivity (0.6163-0.9638), moderate-low emissivity (0.9639-0.9709), moderate emis-sivity (0.9710-0.9724), moderate-high emissivity (0.9725-0.9738), and high emissivity (0.9739-0.9999). The percentages of areas with low emissivity, moderate-low emissivity and moderate emissivity are, respectively, about 20%, 10% and 20%. The moderate-high emis-sivity region makes up 40%-50% of China’s land surface area. The inter-annual variation of moderate-high emissivity region is also very clear, with two peaks (in spring and autumn) and two troughs (in summer and winter). The inter-annual variation of the high emissivity region is very significant, with a peak in winter (10%), while only 1% or 2% in other seasons. There is a clear association between the spatio-temporal distribution of China’s land surface emissivity and temperature: the higher the emissivity, the lower the temperature, and vice versa. Emis-sivity is an inherent property of any object, but the precise value of its emissivity depends very much on its surrounding environmental factors.