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。     

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.     

基于TIN的体布尔算法及其地质应用

提出一种基于TIN的体布尔操作算法,即采用快速碰撞检测方法、改进的三角形求交算法和三角形包含测试算法,能解决复杂地质体的交、并、差等布尔操作。该方法不仅可以有效处理具有侵入、交错等复杂空间关系的地质体建模问题,还适用于基于地质模型的工程分析应用,如开挖模拟等,并在北京市某岩土工程信息系统建设项目中得到了检验。     

Geochemistry of Permian Coal and Its Combustion Residues in Huainan Coalfield, China

INTRODUCTIONMany environmental problems may arise during coal min-ing and utilization. Among these prob1ems, much attention hasbeen paid to S(), and NO. emission during coal combustion.But the environmental effects produced by hazardous elementsduring coal mining and utilization are also important and de-serve to be studied (Goodazi, 1995; Finkelman, 1993; Valk-ovic, l983). For example, when coal wastes are used for landreclamation, the harmful elements in them may pollute water,soil an…     

石嘴山双纪煤田煤中矿物特征对比研究

以石嘴山煤田汝箕沟矿区侏罗纪的二煤、三煤和石炭井矿区二叠纪的四煤、五煤为研究对象,采用低温灰的化学组成分析和X射线衍射分析,对煤中矿物特征做对比研究。结果表明:汝箕沟矿区样品与石炭井矿区样品在化学成分、灰成分指数、Si和Al比值上,都具有明显差异;汝箕沟矿区样品X衍射图谱的波峰最大值远远小于石炭井矿区的样品值,两者的图谱形态也存在很大差异;汝箕沟矿区样品中以高岭石、伊利石、石英为主,其它很少,高岭石约占65%;石炭井矿区样品中以高岭石占绝对优势,约占85%,其他矿物含量较少。化学组成分析的结果和X射线衍射分析的结果具有较好的对应性。     

储层砂岩中自生绿泥石对孔隙结构的影响——来自鄂尔多斯盆地上三叠统延长组的研究结果

通过对鄂尔多斯盆地陇东地区延长组10个砂岩样品的薄片分析、X射线衍射分析、扫描电子显微镜分析、物性分析和压汞分析,研究了这些砂岩中自生绿泥石含量与各种孔隙结构参数之间的关系。研究结果表明：①在孔隙度变化不大的情况下,随着自生绿泥石含量的增加,砂岩的渗透率降低,排驱压力和中值压力增加,与之对应的喉道半径显著减小,同时喉道均值和各种类型喉道的百分数也都显著降低。②自生绿泥石含量的增加可以改善喉道的分选性和非均质性,但这是牺牲了大喉道的数量来实现的。③砂岩中自生绿泥石含量的增加还会显著降低退出效率。因此,在孔隙度类似的前提下,以孔隙衬里方式产出的自生绿泥石含量的增加,会降低砂岩储层的质量并影响烃类开发的效果。     

江苏北部一次由MCC引发的致洪暴雨综合分析

利用卫星云图、NCEP资料和MICAPS系统提供的实况资料和物理量等,对2008年7月23日江苏北部一次中尺度对流复合体（MCC）和暴雨天气过程进行诊断分析。结果表明：MCC是造成暴雨的直接影响系统;200hPa中尺度反气旋环流的形成．配合500hPa西南急流左侧切变线生成以及边界层925hPa锋生与西南强风带或西南急流左侧中尺度低涡生成,有利于MCC生成和发展：925hPa以下边界层10．7m·s^-1·km^-1强风速垂直切变的形成,配合边界层正涡度中心生成、对流层高层辐散增强,是激发MCC生成和发展的动力机制;850hPa江苏中北部MPV1≤-0．5PVU的中尺度对流不稳定中心的生成,配合北方MPV2≥0．6PVU湿斜压场纬向高值带的生成和稳定,有利于江苏北部地区中尺度强对流系统重复出现和MCC生成发展。     

黄河上游龙羊峡水库春季入库流量预报模型研究

The catchment above Longyangxia Gorge in the upper Yellow River basin is situated in the northeast of the Tibetan Plateau. Meltwater from snow is the main water supply to the rivers in this region during spring (late March to early June). In this paper, the study target is the inflow to the Longyangxia Reservoir, the largest reservoir in the upper Yellow River basin, during late March to early June. Then a mid-term operational runoff prediction model based on snow cover data from AVHRR images of NORR meteorological satellite and ground surface hydro-meteorological data, called double sifting and stepwise regression model, is presented to forecast the inflow during this period. Examining at the reservoir shows that the forecast accuracy is satisfying.     

Kinetic Model of Gaseous Alkanes Formed from Coal in a Confined System and Its Application to Gas Filling History in Kuqa Depression, Tarim Basin, Northwest China

Based on the pyrolysis products for the Jurassic low-mature coal under programmed temperature,and chemical and carbon isotopic compositions of natural gas from the Kuqa Depression, the genetic origin of natural gas was determined,and then a gas filling model was established,in combination with the geological background of the Kuqa Depression.The active energy of CH_4,C_2H_6 and C_3H_8 was gotten after the data of pyrolysis gas products under different heating rates(2℃/h and 20℃/h)were fitted by the Gas O...     

渤海东部晚更新世以来的沉积物地球化学特征

为探讨渤海东部晚更新世以来的元素地球化学特征及控制因素,对渤海东部DLC70-1孔157个沉积物样品进行了化学成分、粒度及测年分析。结果表明,晚更新世以来研究区沉积物的物质来源与沉积环境较为稳定;根据DLC70-1孔沉积物地球化学特征,钻孔岩芯可划分为6层,反映了末次间冰期（暖期）晚期以来渤海东部沉积物物源的变化以及海面波动。Al₂O₃、MgO、TFe₂O₃、MnO、TiO₂、Cu、Zn、Pb、Cr和Rb等元素与细粒沉积物呈正相关,SiO₂、Na₂O与粗粒沉积物呈正相关,K₂O、Sr和Ba分布与沉积物粒度无明显正或负的相关性;R-型因子分析得出三种主要组合类型,以Mg、Sr和Ba为代表,分别对应陆源细粒物质输入与黄河物质、海河物质和滦河物质的影响。运用Ba/Al₂O₃与Sr/Al₂O₃、MgO/Al₂O₃与K₂O/Al₂O₃离散图分析了DLC70-1孔的物质来源,结果表明沉积物主要来源于黄河,该孔中上部32.30~49.00 m和9.30~23.20 m沉积物受到了滦河和海河物质的影响。