第三次全国国土调查土地利用矢量数据栅格化方法

第三次全国国土调查县级土地利用图斑层包含利用类型、耕地类型、坡度等级、种植属性等多属性信息,将县级土地利用矢量数据集成栅格化形成全国无缝的多尺度、多专题栅格产品存在一定技术难度。本文针对第三次全国国土调查土地利用栅格产品应用需求,探讨了多属性综合编码、全国基础地理网格框架、栅格化产品数据模型、矢量栅格化等技术方法,建立了全国土地利用栅格产品生产流程,开展了全国多尺度、多专题土地利用栅格产品生产验证。结果表明:本文方法能够实现第三次全国国土调查土地利用矢量图斑多属性信息集成栅格化和全国多尺度、多专题土地利用栅格产品工程化生产,可为今后的国土调查土地利用栅格产品生产和共享应用提供支撑。     

土地利用碳排放核算系统设计与实现

针对土地利用碳排放核算方法的参数设置烦琐、计算过程复杂等缺点,限制了碳排放核算模型广泛应用于我国土地利用/覆被变化导致的碳收支研究。本文选择了簿记模型基本原型作为核心算法,构建一套包含土地开垦/退耕、森林收获/恢复4种情景在内的土地利用碳排放核算系统。系统以地理区域为核算基本单元,可逐年并行核算多个区域土地利用活动导致的土壤和植被直接碳排放,提高了碳排放估算的效率;系统界面简洁明了、输入参数少、操作简便。     

Crime on the edges: patterns of crime and land use change

ABSTRACT

Criminologists have long-known that different locations have varying levels of risk for criminal victimization. Based on the geometry of crime and its corresponding crime generators and crime attractors, edges (boundaries between relatively homogeneous neighborhoods) are locations with an elevated risk of criminal victimization. In this article, we investigate the importance of edges. We find that criminal victimization rates are 2–3 times on an edge compared to elsewhere. However, this effect decreases very quickly moving away from these locations, with the effect gone at 40 meters. This general effect is identified in a number of contexts and locations.     

基于VB + MapObjects的土地利用动态变化更新与实现

在土地利用动态监测中,地理信息系统是实现空间数据动态更新和分析的主要技术手段。本文分析了土地利用动态变化更新模式、土地利用图中图斑的特点以及图斑对象的更新模型,结合土地利用动态变化更新中的GIS空间分析方法,给出了土地利用动态变更中的图斑模型,采用VB+MapObjects进行了组件式GIS二次开发实现。经过实际数据的检验,证明了程序具有很好的稳定性、可靠性和较高的效率。     

Remote sensing-derived national land cover land use maps: a comparison for Malawi

Reliable land cover land use (LCLU) information, and change over time, is important for Green House Gas (GHG) reporting for climate change documentation. Four different organizations have independently created LCLU maps from 2010 satellite imagery for Malawi for GHG reporting. This analysis compares the procedures and results for those four activities. Four different classification methods were employed; traditional visual interpretation, segmentation and visual labelling, digital clustering with visual identification and supervised signature extraction with application of a decision rule followed by analyst editing. One effort did not report classification accuracy and the other three had very similar and excellent overall thematic accuracies ranging from 85 to 89%. However, despite these high thematic accuracies there were very significant differences in results. National percentages for forest ranged from 18.2 to 28.7% and cropland from 40.5 to 53.7%. These significant differences are concerns for both remote-sensing scientists and decision-makers in Malawi.     

基于CLUE-S模型的南京市土地利用变化模拟

本文以南京市为研究区,以南京市1986年的土地利用现状图为基础,分析研究区概况并根据数据的可获取性,选取13类土地利用变化驱动因素,利用逻辑斯蒂回归分析求解土地利用变化驱动因素作用系数矩阵。在此基础上运行CLUE-S模型,对南京市1996年的土地利用空间格局进行模拟。将模拟结果与南京市1996年土地利用现状图与进行对比,结果较为理想,模拟正确率达88.57%,KAPPA指数0.86。这说明CLUE-S模型具有成功模拟区域土地利用时空动态变化的能力,对土地利用预测、规划具有重要的指导作用。     

基于RS的平顶山市土地利用动态变化研究

平顶山市作为典型的资源型城市(以煤炭、耕地发展起来),是人地关系作用最强烈的区域之一,也是土地利用发生急剧变化且具有特色的区域。为此,基于平顶山市城区1994年TM和2002年ETM+两个时段的遥感图像,获取不同时期的土地利用信息,求取土地利用转移矩阵,分析土地利用的时空变化特征和变化规律,并从土地利用面积变化、动态度、耗减度、开发度等方面对土地利用变化进行分析。研究发现:煤炭开采、城市发展对平顶山市土地利用变化具有重要的影响;8年间,该地区耕地、林地大幅减少,城市用地、工矿用地、荒草地大幅增加;减少的耕地主要转化为荒草地、工矿用地、城市用地,减少的林地主要转化为荒草地;受北部矿区条件的影响,市区发展主要朝东、西、南三个方向。     

InSAR和地表覆盖的地表沉降驱动力分析

针对传统地表沉降监测和成因分析无法实现大规模应用的问题,该文采用一种结合InSAR和地表覆盖数据的多源数据监测和分析方法。通过对Envisat数据集和哨兵1号数据集时序处理中的配准技术进行重点攻关,获取大范围、高精度、多时相的地表沉降成果;然后结合相应年度的地表覆盖数据进行多要素数据的空间拓扑分析,确定地表沉降变化变化的驱动力。以天津市汉沽为例,开展多源InSAR数据、多时相地表覆盖数据的地表沉降监测和分析,发现大面积水域的减少、构筑物和房屋建筑的增加等反映城市建设的指标与地表沉降加剧有密切关系,并结合天津市总体规划进行验证分析。实验结果表明,基于InSAR和地表覆盖方法对于地表沉降驱动力分析的有效性,可为后续城市地表沉降灾害防治和可持续发展应用提供参考。     

Application of remote sensing technology for land use/land cover change analysis

Land use/land cover changes over a period of 30 years were studied using remote sensing technology in a part of Gohparu block, Shahdol district of Madhya Pradesh. Land use/ land cover maps were prepared by visual interpretation of two period remotely sensed data. Post-classification comparison technique was adopted for this purpose. The loss of vegetation cover was estimated to be 22 percent and 14 percent of the land was found to have been tranformed into wasteland between 1967 and 1996. Overall rate of change was found to be 1.8 percent per year during this period.     

青海西部土地利用格局时空变化分析

本文以西部测图成果数据为基础,经拓扑检查与纠正、合并、裁剪、拼接、相交及化简等空间数据处理后得到青海省西部两县对比数据,将所得矢量数据转入ArcInfo中,对两期数据进行空间叠置分析,获得土地利用变化的空间数据与属性数据,构建分形指数模型、地类图斑格局指数模型,计算各地类的分形维值、稳定性指数及景观格局指数,根据复杂程度和稳定性指数对两县的地类进行排序,并根据各景观格局指数,分析8年间两县的土地利用格局变化和生态学意义。     

基于孪生神经网络的土地利用现状年度变化检测

近年来,利用多期高分遥感影像,构建土地利用现状年度变化检测模型,并以此为基础支持土地利用现状年度变化检测的智能化发展,正是当前研究的难点所在.本文探讨了构建土地利用现状年度变化检测模型存在的问题.通过对土地资数据进行预处理,构建基于孪生神经网络的变化检测模型,以及对模型输出结果进行GIS优化获取目标区域的变化图斑,实现...     

地理国情地表覆盖的城市建设用地扩张分析——以兰州新区为例

针对传统的土地利用变化研究方法无法实现大规模在建中的建设用地动态监测的问题,该文提出了一种新的动态监测方法。结合多时相遥感影像、规划数据和外业调查数据,能够快速、低成本地提取城市建设用地。选取合适的扩展指数构建综合扩展程度指数模型,便于对建设用地变化时序特征做出评价。定量分析建设用地变化时序特征与规划用地的对比情况,明确了城市建设用地的建设进度和符合度。结果表明,城市建设用地处于高速扩展阶段,建设现状和规划情况基本相符;该方法是对地理国情监测工作的一种新的探索。     

Historical effects of dissolved organic carbon export and land management decisions on the watershed-scale forest carbon budget of a coastal British Columbia Douglas-fir-dominated landscape

Background

To address how natural disturbance, forest harvest, and deforestation from reservoir creation affect landscape-level carbon (C) budgets, a retrospective C budget for the 8500 ha Sooke Lake Watershed (SLW) from 1911 to 2012 was developed using historical spatial inventory and disturbance data. To simulate forest C dynamics, data was input into a spatially-explicit version of the Carbon Budget Model-Canadian Forest Sector (CBM-CFS3). Transfers of terrestrial C to inland aquatic environments need to be considered to better capture the watershed scale C balance. Using dissolved organic C (DOC) and stream flow measurements from three SLW catchments, DOC load into the reservoir was derived for a 17-year period. C stocks and stock changes between a baseline and two alternative management scenarios were compared to understand the relative impact of successive reservoir expansions and sustained harvest activity over the 100-year period.

Results

Dissolved organic C flux for the three catchments ranged from 0.017 to 0.057 Mg C ha^?1 year^?1. Constraining CBM-CFS3 to observed DOC loads required parameterization of humified soil C losses of 2.5, 5.5, and 6.5%. Scaled to the watershed and assuming none of the exported terrestrial DOC was respired to CO₂, we hypothesize that over 100 years up to 30,657 Mg C may have been available for sequestration in sediment. By 2012, deforestation due to reservoir creation/expansion resulted in the watershed forest lands sequestering 14 Mg C ha^?1 less than without reservoir expansion. Sustained harvest activity had a substantially greater impact, reducing forest C stores by 93 Mg C ha^?1 by 2012. However approximately half of the C exported as merchantable wood during logging (~176,000 Mg C) may remain in harvested wood products, reducing the cumulative impact of forestry activity from 93 to 71 Mg C ha^?1.

Conclusions

Dissolved organic C flux from temperate forest ecosystems is a small but persistent C flux which may have long term implications for C storage in inland aquatic systems. This is a first step integrating fluvial transport of C into a forest carbon model by parameterizing DOC flux from soil C pools. While deforestation related to successive reservoir expansions did impact the watershed-scale C budget, over multi-decadal time periods, sustained harvest activity was more influential.

     

基于GIS的岷江上游流域土地利用／覆被变化研究

以岷江上游流域为对象,选取3期9景TM/+ETM遥感影像,通过多步骤最大似然监督分类、变化检测,结合空间动态分析测算模型,分析近20年土地利用/覆被变化情况。结果表明:从整个流域分析,林地面积减少,主要转化为未利用地、建设用地和耕地;未利用地在前8年以每年3.7%、后8年以每年0.4%的速度增加;建设用地在1994—2002年以每年34%的速度增加,到2002—2010年增长速度减缓;耕地总面积减少54 431hm2;从县域分析,1994—2002年间,松潘和黑水县大面积林地转为未利用地;2002—2010年间,松潘县未利用地转为林地和建设用地,茂县和汶川县未利用地面积大幅增加。该研究结论不仅为国土资源管理部门优化土地利用结构提供依据,亦为当地政府实现生态资源可持续发展提供数据支撑。     

Integrating the system dynamic and cellular automata models to predict land use and land cover change

Land use and land cover change (LULCC) is a widely researched topic in related studies. A number of models have been established to simulate LULCC patterns. However, the integration of the system dynamic (SD) and the cellular automata (CA) model have been rarely employed in LULCC simulations, although it allows for combining the advantages of each approach and therefore improving the simulation accuracy. In this study, we integrated an SD model and a CA model to predict LULCC under three future development scenarios in Northern Shanxi province of China, a typical agro-pastoral transitional zone. The results indicated that our integrated approach represented the impacts of natural and socioeconomic factors on LULCC well, and could accurately simulate the magnitude and spatial pattern of LULCC. The modeling scenarios illustrated that different development pathways would lead to various LULCC patterns. This study demonstrated the advantages of the integration approach for simulating LULCC and suggests that LULCC is affected to a large degree by natural and socioeconomic factors.     

Implications of sampling design and sample size for national carbon accounting systems

Background  

Countries willing to adopt a REDD regime need to establish a national Measurement, Reporting and Verification (MRV) system that provides information on forest carbon stocks and carbon stock changes. Due to the extensive areas covered by forests the information is generally obtained by sample based surveys. Most operational sampling approaches utilize a combination of earth-observation data and in-situ field assessments as data sources.     

城市路网变化信息提取及其对土地利用的影响研究

城市路网作为一种特殊的土地覆盖类型,与土地利用相互作用.现代城市系统中道路变化越来越频繁,如何快速精确的对城市路网的变化信息进行提取不仅可以支撑路网基础测绘数据的更新需要,也可以为城市土地利用提供辅助支持.论文基于遥感和矢量数据进行道路网变化信息提取,分析城市路网结构和变化与土地利用的关联关系.     

小尺度土地利用变化模型在岩溶山区的应用

针对当前土地利用模拟技术在岩溶地区应用较少的现状,该文提出了利用CLUE-S模型对岩溶地区土地利用变化进行模拟。此模型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,具有综合性、开放性、空间性、竞争效率性等特点。研究结果表明:该模型不仅能够准确地反映未来研究区土地利用变化趋势,而且能较好地筛选影响未来土地利用变化主要影响因子,进行不同情景土地利用变化模拟,对岩溶地区土地利用规划和管理具有参考价值。     

自然湿地鹤类数量对土地利用变化的响应

鹤类是我国重点野生保护动物,近年来,随着人类活动的加强,鹤类数量变化显著。为了保护鹤类提供更好的依据,该文文章以升金湖自然湿地为例,研究鹤类种群数量对土地利用变化的响应。文章利用软件提取升金湖八期TM遥感影像的土地利用信息;利用土地利用动态度、物种多样性,分析土地利用变化特征及各地类生境鸟类的多样性。对比1986—2015年升金湖越冬鹤类的种群数量变化,以及土地利用变化,分析结果表明:鹤类数量与土地利用类型存在一定相关,湿地内芦苇滩地、泥滩地、草滩地、水田、建设用地等的土地类型变化,对鹤类数量影响较大。     

基于GIS的岳阳县土地利用变化研究

本文利用遥感和GIS技术,分析了岳阳县1993年～2002年土地利用变化及其空间分异特征。研究表明,9年间岳阳县农用地、水域呈减少趋势,建设用地、林地呈增加趋势,其中农用地的减少和林地的增加十分显著;主要转移方向包括农用地向建设用地、林地转移,水域向林地转移等;各类土地利用变化在空间上呈现明显的区域分异;城市化的迅速发展,旅游业的繁荣以及人类生态意识的提高是研究时段内土地利用变化的主要影响因子。