{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# 14.1 遥感专题制图面临的问题" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "(1)遥感影像质量受成像条件影响大:大气状况多变,地形的复杂程度,都会影响遥感影像的质量,导致影像不能反映地表真实情况。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![1](TP/cloude.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "(2)传感器本身的质量问题:传感器在成像时可能出现多种误差,甚至出现错误,因此需要对数据进行误差校正,修复错误数据。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![2](TP/ETML.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "(3)遥感影像时空不连续:由于多种因素的影响,地表某些区域没有影响覆盖,或者是覆盖不完全,\n", "\n", "在某些时间点上没有数据,在实际研究中需要重建这些缺失的影像数据。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![3](TP/time.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# 14.2 水体遥感制图" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "A.纯净水体:在TM/ETM+7, 4, 3 波段合成的影像上呈现深蓝色, 且在各个波段光谱高吸收、低反射,光谱曲线整体很低;(光谱上容易与图像阴影想混淆)\n", "\n", "\n", "B. 含泥沙浑浊水体:在7, 4, 3 合成的影像上呈现浅蓝色, 由于河流泥沙反射的原因, 使得光谱反射率比纯净的水体要高, 从1 波段到4 波段反射率逐渐增高, 5 波段和6 波段反射率骤降, 致使诸如浅水河流等水体与周边裸土容易混淆, 边界不明显。\n", "\n", "\n", "C.富营养化的水体:在4, 3, 2 波段合成的图像上偏红, 与植被的光谱相似, 在波段3 有吸收谷, 波段4有反射峰,但和植被相比, 整体的反射较低" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![4](TP/water.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "水体信息提取:基于多源遥感影像,依据归一化水体指数NDWI、归一化植被指数NDVI等多种特征参数,\n", "\n", "利用SVM、面向对象分类等多种机器学习分类算法,能够提取出水体,制图流域、河网等专题地图。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![5](TP/classwater.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "基于SVM和面向对象分割的水体提取效果:" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![6](TP/classwaterSVM.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ " The European Commission's science and knowledge service ----- Global Surface Water Explorer: https://ec.europa.eu/jrc/en/scientific-tool/global-surface-water-explorer" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "全球地表水体制图数据集:https://global-surface-water.appspot.com/" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![7](TP/gloabalwater.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# 14.3 植被遥感制图" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "陆表植被对地球生态环境具有极其重要的作用,根据遥感影像动态提取地表植被,这对于监测植被状况和保护生态环境具有重要意义。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![8](TP/VG.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "全球森林植被遥感监测数据:http://globalforestchange.org/" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![9](TP/GEEForst.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "MODIS数据有多种植被遥感参数的产品,可用来提取陆表植被信息" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![10](TP/MODISVG.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# 14.4 建设用地制图" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "建设用地:建造建筑物、构筑物的土地,是城乡住宅和公共设施用地,工矿用地,能源、交通、水利、通信等基础设施用地,旅游用地,军事用地等,\n", "\n", "付出一定投资(土地开发建设费用),通过工程手段,为各项建设提供的土地。是利用土地的承载能力或建筑空间,不以取得生物产品为主要目的的用地。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![11](TP/building.JPG)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "纹理特征(PANTEX):反映建筑区较高的辐射反差(建筑vs阴影)。\n", "\n", "形态特征(mtDAP):multi-scale Differential Attribute Profile (DAP)\n", "\n", "基于多种特征聚合,采用面向对象的思想,可以从高分影像中提取出建设用地,且能达到较高的精度。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "![12](TP/classbuild.JPG)" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.6.4" }, "toc": { "colors": { "hover_highlight": "#DAA520", "navigate_num": "#000000", "navigate_text": "#333333", "running_highlight": "#FF0000", "selected_highlight": "#FFD700", "sidebar_border": "#EEEEEE", "wrapper_background": "#FFFFFF" }, "moveMenuLeft": true, "nav_menu": { "height": "84px", "width": "252px" }, "navigate_menu": true, "number_sections": true, "sideBar": true, "threshold": 4, "toc_cell": false, "toc_section_display": "block", "toc_window_display": true, "widenNotebook": false } }, "nbformat": 4, "nbformat_minor": 2 }