富锦市土地利用景观格局遥感分析

针对基于小尺度的县域土地利用变化监测成果比较缺乏的问题,该文结合GIS、RS技术,采用11个景观格局指数,分析富锦市2000年和2009年土地利用景观格局变化。结果表明:近10年间,耕地是该市最大的景观类型;整个景观的破碎化程度增加显著,各景观类型之间的分布关系变得复杂,分布逐渐趋向分散,景观类型向着多样化和均衡化方向发展;人文驱动是富锦市近10年景观格局动态变化的主要驱动因素。     

A comparison of unsupervised segmentation parameter optimization approaches using moderate- and high-resolution imagery

Unsupervised segmentation optimization methods have been proposed to aid in selecting an “optimal” set of scale parameters quickly and objectively for object-based image analysis. The goal of this study was to qualitatively assess three unsupervised approaches using both moderate-resolution Landsat and high-resolution Ikonos imagery from two study sites with different landscape characteristics to demonstrate the continued need for analyst intervention during the segmentation process. The results demonstrate that these methods selected parameters that were optimal for the scene which varied with method, image type, and site complexity. Several takeaways from this exercise are as follows: (1) some methods do not work as intended, (2) single-scale unsupervised optimization procedures cannot be expected to properly segment all the features of interest in the image every time, and (3) many multi-scale approaches require subjectively chosen weights or thresholds or additional testing to determine those values that meet the objective. Visual inspection of segmentation results is still required in order to assess over and under-segmentation as no method can be expected to select the best parameters for land cover classifications every time. These approaches should instead be used to narrow down parameter values in order to save time.     

安徽省含山县土地整理耕地质量评价及其变化研究

土地整理是改善土地利用条件,提高土地质量的有效措施,对土地整理后的耕地质量进行评价是土地整理重要工作之一。从耕地质量的内涵和土地整理项目的基本要求出发,选取耕地自然条件和耕地利用条件2个基本因素和12个影响因子,将特尔斐法与层次分析法相结合,确定各因子权重,构建基于土地整理的耕地质量评价指标体系。以安徽省含山县铜闸镇土地整理项目为例,采用传统的土壤调查与3S技术相结合的方法,分析土地整理复垦过程中耕地质量时空格局变化,得出整理前、后耕地质量的级别变化。研究结果表明,通过土地整理,研究区的耕地质量空间分布和级别发生了很大变化,整理后一级、二级、三级质量的土地比整理前分别增加了7.20%,11.95%和0.65%,四级、五级则分别减少了15.65%和4.16%,整理后的耕地质量总体水平是整理前的1.291倍。     

Estimating crop net primary production using national inventory data and MODIS-derived parameters

National estimates of spatially-resolved cropland net primary production (NPP) are needed for diagnostic and prognostic modeling of carbon sources, sinks, and net carbon flux between land and atmosphere. Cropland NPP estimates that correspond with existing cropland cover maps are needed to drive biogeochemical models at the local scale as well as national and continental scales. Existing satellite-based NPP products tend to underestimate NPP on croplands. An Agricultural Inventory-based Light Use Efficiency (AgI-LUE) framework was developed to estimate individual crop biophysical parameters for use in estimating crop-specific NPP over large multi-state regions. The method is documented here and evaluated for corn (Zea mays L.) and soybean (Glycine max L. Merr.) in Iowa and Illinois in 2006 and 2007. The method includes a crop-specific Enhanced Vegetation Index (EVI), shortwave radiation data estimated using the Mountain Climate Simulator (MTCLIM) algorithm, and crop-specific LUE per county. The combined aforementioned variables were used to generate spatially-resolved, crop-specific NPP that corresponds to the Cropland Data Layer (CDL) land cover product. Results from the modeling framework captured the spatial NPP gradient across croplands of Iowa and Illinois, and also represented the difference in NPP between years 2006 and 2007. Average corn and soybean NPP from AgI-LUE was 917 g C m⁻² yr⁻¹ and 409 g C m⁻² yr⁻¹, respectively. This was 2.4 and 1.1 times higher, respectively, for corn and soybean compared to the MOD17A3 NPP product. Site comparisons with flux tower data show AgI-LUE NPP in close agreement with tower-derived NPP, lower than inventory-based NPP, and higher than MOD17A3 NPP. The combination of new inputs and improved datasets enabled the development of spatially explicit and reliable NPP estimates for individual crops over large regional extents.     

基于特征基元的高分辨率遥感影像道路网自动提取技术

高分辨率遥感道路网络的自动提取在城市信息更新等方面具有非常重要的意义。在综述国内外道路信息提取进展的基础上,本文提出一套基于特征基元的道路网提取方法体系。即采取自下而上的研究路线("影像像元—特征基元—道路单元—道路网络"):首先通过影像大尺度的区域划分获取道路区域,在此基础上进行小尺度分割,提取出特征基元;然后根据基元的形态、走向、亮度、纹理等特征对基元进行模式分类,识别出道路单元;最后根据道路网语义规则将道路单元进行形态学处理及拓扑连接,形成道路网络。     

Polarimetric synthetic aperture radar change detection for specific land cover types

This paper presents a supervised polarimetric synthetic aperture radar (PolSAR) change detection method applied to specific land cover types. For each pixel of a PolSAR image, its target scattering vector can be modeled as having a complex multivariate normal distribution. Based on this assumption, the joint distribution of two corresponding vectors in a pair of PolSAR images is derived. Then, a generalized likelihood ratio test statistic for the equality of two likelihood functions of such joint distribution is considered and a maximum likelihood distance measure for specific land cover types is presented. Subsequently, the Kittler and Illingworth minimum error threshold segmentation method is applied to extract the specific changed areas. Experiments on two repeat-pass Radarsat-2 fully polarimetric images of Suzhou, China, demonstrate that the proposed change detection method gives a good performance in determining the specific changed areas in PolSAR images, especially the areas that have changed to water.     

Global operational land imager Landsat-8 reflectance-based active fire detection algorithm

A global operational land imager (GOLI) Landsat-8 daytime active fire detection algorithm is presented. It utilizes established contextual active fire detection approaches but takes advantage of the significant increase in fire reflectance in Landsat-8 band 7 (2.20?μm) relative to band 4 (0.66?μm). The detection thresholds are fixed and based on a statistical examination of 39 million non-burning Landsat-8 pixels. Multi-temporal tests based on band 7 reflectance and relative changes in normalized difference vegetation index in the previous six months are used to reduce commissions errors. The probabilities of active fire detection for the GOLI and two recent Landsat-8 active fire detection algorithms are simulated to provide insights into their performance with respect to the fire size and temperature. The algorithms are applied to 11 Landsat-8 images that encompass a range of burning conditions and environments. Commission and omission errors are assessed by visual interpretation of detected active fire locations and by examination of the Landsat-8 images and higher spatial resolution Google Earth imagery. The GOLI algorithm has lower omission and comparable commission errors than the recent Landsat-8 active fire detection algorithms. The GOLI algorithm has demonstrable potential for global application and is suitable for implementation with other Landsat-like reflective wavelength sensors.     

青藏高原少数民族聚居地区城镇用地扩展时空演变分析——以青海省海东市为例

基于多期遥感影像数据,采用GIS空间叠加分析技术,选择扩展强度指数、紧凑度、分形维数、重心转移指数和扩展方位指数,定量分析了海东市1990—2016年间城镇用地扩展时空分异特征.研究结果表明,海东市城镇用地持续增加,扩展强度呈现先降低后升高的中速持续扩展趋势,城镇从空间无序转向空间协同发展;城镇用地紧凑度持续下降,分形...     

基于高分辨率遥感影像的耕地地块提取方法研究

针对耕地地块提取问题,提出了一种基于图像分割的耕地地块提取新方法。该方法以高分辨率遥感影像为基础,借助于边缘提取和数学形态学的方法,通过边缘检测、边缘闭合、区域标号和后处理四个步骤,提取耕地地块。该方法在IDL6.3平台下编程实现。将此方法应用于北京地区QuickBird多光谱遥感影像,结果表明此方法有较好的定位精度,又在一定程度上去除了噪声,具有较好的实用性。     

五种分割算法在高分辨率遥感图像中的适用性分析

本文将5种图像分割算法应用在高分辨率遥感图像分割上,并利用图像分割评价指标,对5种分割算法进行了对比分析,评价了各种方法的优缺点,讨论了它们在高分辨率遥感图像分割中的适用性,明确了不同分割方法的适用条件。实验结果表明,改进的分水岭分割法与JSEG分割法在高分辨率遥感图像分割中的适用性比较强,对大小斑块分割结果都比较好,而其他3种方法不能兼顾不同等级的斑块。     

生态敏感性限制下的城市建设用地适宜性评价

针对当前城市规划中对建设用地适宜性评价框架的不尽合理问题,以河南省西峡县为例构建了包含主导性和限制性逻辑的综合评价方案。利用遥感与地理信息系统相结合的方法,将生态敏感性作为限制性因素进行城市建设用地适宜性研究。研究区的分析结果显示:西峡县整体新增城镇建设区呈现南北区域不适宜而中间适宜的特征,而适宜和较适宜城市建设的用地主要分布在鹳河及其支流形成的河谷地带。但在中心城区外缘某些区域生态敏感性强,应禁止开发活动。研究结果有效体现出建设用地和生态用地的空间格局,对城市总体规划具有一定的参考价值。     

环境遥感的学科地位

地理科学对地理环境系统的研究是以地理信息获取的研究为基础的,后者制约着地理科学研究方法的进步,并影响了整个地理科学的发展水平。现代遥感技术辅之以系统科学等一系列先进的科学理论和技术,在地理环境系统研究中的成功应用,形成遥感技术的一个重要应用分支学科——环境遥感,其作为地理科学研究技术工具学科的地位逐渐确立。 环境遥感研究的实质表现为三个方面:(1)地理环境系统中电磁相互作用关系的充分利用;(2)遥感信息机制研究支持下的地理环境信息处理系统的结构优化;(3)地理环境系统综合分析过程标准化的实现。 环境遥感的学科地位体现为双重特征,即重要的遥感应用分支和现代地理科学研究新的技术方法。由于横跨信息科学和地理科学两大领域,环境遥感充分体现出其综合性、交叉性的学科特点。环境遥感和常规的地理研究方法,分别着重于对地理环境系统中能量信息系统或物质信息系统的考察,两者在某些方面,至少在今天看来是不能互相取代的。但是,环境遥感依靠其技术系统的不断完善、综合分析功能的加强以及对一系列非能量信息的参照和相关分析(如信息复合技术)而在地理环境系统研究的很多领域显示出独特的优越性。 同时,由于科学认识和科学技术水平的整体制约,以及学科本身的固有特性,环境遥感研究仍     

房屋震害预测数字化辅助方法

为提高房屋震害预测效率,将数字化技术应用于房屋震害预测分类工作中。利用航空摄影测量、遥感及地理信息系统技术,提出两种房屋震害预测分类数字化辅助方法。若预测区域有符合条件的遥感影像对,利用航空摄影测量技术可获得DSM及DEM模型,进一步从层数上对建筑物进行分类。另一种方法则是利用遥感技术提取有关建筑物阴影信息,由阴影计算建筑物层数,进而对建筑物进行分类。利用地理信息系统自动统计不同类建筑物总面积,画出不同类建筑的地理分布图。与传统方法相比,这种方法效率高,可以纵览全局,减少房屋震害预测现场调查工作量,提高震害预测工作效率。     

遥感影像在内蒙古典型自然景观地图制作中的应用

在分析遥感影像优势的基础上,以《内蒙古自治区典型自然景观图集》的制作为例探讨了遥感影像在山脉、河湖湿地、森林、耕地、草地、沙漠戈壁、沙地及聚落等景观表达中的应用,有助于理解山、水、林、田、湖、草、沙的空间分布规律,可为自然资源治理提供服务。     

遥感技术用于大型单体滑坡风险评估与管理

本文以平武县文家坝滑坡为研究对象,从地质、地貌、水文3方面分析了该滑坡形成的条件;以遥感地质学相关理论为指导,在地质资料、地形图、CPS数据的支撑下,经过实地验证,建立了滑坡解译标志;对震后SPOT5影像进行解译,提取出滑坡周界、滑坡要素等信息,估算出滑坡规模,分析了滑坡的发育特征;确定滑坡的坡度、岩性、地震因素、水文...     

煤炭开采对泥河小流域土地利用及景观格局的影响

以淮南煤矿区泥河小流域1987、1994、2000、2006、2009、2013、2017年7期多源遥感影像为数据源,结合纹理和光谱特征,利用支持向量机（SVM）对遥感影像进行分类,在此基础上分析了煤炭开采对泥河小流域近30年土地利用和景观格局变化的影响。结果表明：煤炭开采影响下流域的土地利用变化最显著的特征是耕地和建设用地的相互转变及耕地向塌陷水体的转变,30年间塌陷水体和建设用地分别增加了2 281.05、14 741.73 hm²,耕地减少了15 044.67 hm²。采煤驱动下,流域景观格局变化特征体现在以2006年为转折点,前期呈现破碎化、不规则化、异质化和低连通性变化的特征,之后呈现连续化、规则化、均衡化及高连通性变化的特征。建设用地、耕地和塌陷水体经历了不断破碎化到景观逐渐完善的过程;耕地、建设用地和自然水体斑块形状较为复杂;耕地优势性逐渐减弱,最大斑块指数由79.706 0降为38.745 5,塌陷水体和建设用地的优势性增强。     

Landscape transform and spatial metrics for mapping spatiotemporal land cover dynamics using Earth Observation data-sets

Analysis of Earth observation (EO) data, often combined with geographical information systems (GIS), allows monitoring of land cover dynamics over different ecosystems, including protected or conservation sites. The aim of this study is to use contemporary technologies such as EO and GIS in synergy with fragmentation analysis, to quantify the changes in the landscape of the Rajaji National Park (RNP) during the period of 19 years (1990–2009). Several statistics such as principal component analysis (PCA) and spatial metrics are used to understand the results. PCA analysis has produced two principal components (PC) and explained 84.1% of the total variance, first component (PC1) accounted for the 57.8% of the total variance while the second component (PC2) has accounted for the 26.3% of the total variance calculated from the core area metrics, distance metrics and shape metrics. Our results suggested that notable changes happened in the RNP landscape, evidencing the requirement of taking appropriate measures to conserve this natural ecosystem.     

遥感图像的异质性测度分割效果评价

针对高分辨率遥感图像分割结果的评价问题,提出一种基于异质性测度的非监督分割评价方法。首先,通过全局方差和加权Moran指数分别表示对象内异质性和对象间异质性,并利用二者归一化后的和式来对整体分割结果进行评价。其次,为了进行局部分割结果评价,提出一种基于对象方差和局部Geary指数的异质性测度。最后,利用多分辨率分割方法对遥感图像进行分割,并利用提出的方法进行分割评价。实验结果表明,提出的方法能够对不同分割尺度结果进行有效评价,同时可以对过分割区域和欠分割区域进行判断。     

新一代人工智能驱动的陆地观测卫星遥感应用技术综述

随着各国航天事业的高速发展以及政府对卫星遥感技术的大力支持,各类军民商用卫星系统层出不穷,建立了较为完善的卫星遥感数据获取体系,为推动经济社会高质量发展提供了新动能。与此同时,人工智能技术的迅猛发展极大程度的提升了数据分析的智能化、精准化水平,为遥感大数据分析与应用带来了新的发展机遇。在互联网时代的背景下,结合新一代人工智能、大数据、物联网、5G等先进技术,推动遥感应用朝着智能化、大众化、产业化方向发展是大势所趋。本文依据当前陆地观测卫星智能遥感技术的发展现状与实际需求,论述了人工智能驱动的遥感技术在资源调查、环境监测、灾害监测等领域中的应用研究现状,探讨了现阶段制约人工智能技术在遥感领域应用成效的关键问题,最后结合遥感大数据处理中存在的问题和挑战,对陆地观测卫星遥感应用技术的发展趋势进行了展望,建立基于人工智能的卫星遥感应用体系已成为卫星遥感技术发展的必然趋势。     

内陆河流域典型地类面向对象的图像分类试验

利用了基于面向对象的最近邻法分类,比较了最大似然法的分类结果,得出了其不仅适合高分辨率城市遥感影像的分类,而且在中分辨率土地利用/土地覆盖上也有很好的应用.