利用遥感法研究广州市区大气污染与植被生态变化

利用彩色红外航片研究大气污染与植被生态变化,是遥感技术应用于大气环境研究的新课题。本研究是使用广州市航空遥感综合调查指挥部提供的1:2万比例尺的彩色红外航片及1:1万比例尺的天然彩色航片。我们的做法是根据显示在航片上的植被信息和部分准同步监测结果,建立解译标志,然后进行解译:进一步将准同步监测、历年大气监测、污染源等资料对解译结果作论证;再到现场调查证实。结果表明:彩色红外航片上的植被信息记录了大气污染与植被生态变化的真实情况;从而认为利用航片上的植被信息特征反映大气污染状况及范围是可行的。研究结果为城市规划、管理和环保部门的决策、管理、环境影响评价等提供科学依据。     

天津市彩色红外相片在研究植被与大气污染关系中的应用

利用彩色红外相片来研究城市植被与大气污染的关系,这是遥感技术应用于环境动态研究中的一个重要课题。在研究过程中,使用了中国科学院遥感所提供的天津市1／5000和1／10000比例尺彩色红外相片。我们首先将显示在相片上的植被与大气污染的遥感信息进行了解译,然后取样分析该地植物体中污染物质的含量,最后再到实地验证。结果表明,彩色红外相片记录了当时植被与大气污染的真实状况,具有丰富的信息,植被信息特征能够反映大气污染的基本情况。同时还可发现一些抗性强、吸毒能力大的绿化效应好的树种和绿化结构,可为城市建设、城市环境质量评价提供科学依据。     

遥感和GIS支持下的城市植被制图及其特征分析

 以上海城市植被为研究对象,探索城市植被的分类理论和方法,提出一套适用于城市植被分类与制图的方法。根据城市植被信息获取的方式以及生态-外貌分类原则,建立了基于植物生活型的、可用图形表示的城市植被分类体系,分天然与半天然植被和人工植被两个大类,共有9个植被型和34个植被亚型。在遥感和地理信息系统(GIS)技术的支持下,建立研究区的城市植被信息数据库,并在此基础上对城市植被类型的特征以及与土地利用的关系进行分析比较,以期掌握城市植被类型的数量特征及其空间分布,同时按不同分类级别用计算机进行城市植被制图。城市植被     

城市复合生态系统中互动关系的测度与评价

基于城市复合生态系统原理和城市代谢功能,构建了城市系统互动分析指标体系。应用因子分析法、层次分析法及所建立的量化模型,对城市复合生态系统中的不同变量之间的相关性和协调性进行度量。并以中国北京、上海、广州、天津、重庆和深圳等六大城市为例,对其可持续发展进程进行横向比较。结果表明,六大城市发展度由大到小的顺序是:上海、深圳、广州、天津、北京、重庆;协调度由好到坏的排序是:重庆、上海、广州、北京、天津、深圳;循环度由好到坏的排序是:深圳、上海、天津、北京、广州、重庆;从可持续发展度看,建设和实现可持续发展城市或生态城市的先后顺序大致为:上海、深圳、广州、重庆、天津、北京。说明城市可持续发展的关键取决于社会经济活动压力源的削减、自然生态环境的保育以及城市代谢功能的增强。     

大气污染对城市植被的生态胁迫效应综述

快速的城市化进程使得城市大气污染日趋严重,造成了城市植被的退化及其生态服务功能的下降。大气中的O₃、紫外(UV-B)辐射、重金属、SO₂等污染物及其复合污染从分子、细胞、个体、种群、群落和生态系统各个水平上都对城市植被造成了胁迫效应。本文从微观实验法和宏观高光谱遥感法两方面对已有的研究方法进行了分析和总结后,提出了以下几个今后需要关注的研究领域:开展野外和长期胁迫实验、植物受胁迫机理及多种因子复合胁迫研究等;同时指出应重视建筑物在城市大气污染生态胁迫中的重要作用,并在今后加强城市行道树相关方面的研究。     

全色型及彩色红外型航空像片解译方法在植被制图中的应用

在编制大、中比例尺植被图的过程中,热红外的,多光谱的、彩色红外的和全色型的航空像片都可以利用。我们在云南省腾冲进行了航空遥感试验。根据直接解译标志和间接解译标志的不同组合可以进行植被类型的解译。这种综合的方法用于遥感图像的解译可以获得良好的效果。文中提出以下的直接解译标志,即植物群落影像的颜色、色调及其影纹结构,植物群落、群落片断或单株的形状、大小和高度以及它们的投影形状。间接解译标志包括植物生长地所处的海拔高度、纬度位置和地貌部位以及成土母岩的性质。间接标志还有人类活动对植被分布影响的程度。为了便于进行自动的植被分类,可以用检索表将各植被类型的详细解译标志表示出来。本文列出了位于常绿阔叶林区的云南省腾冲植被类型解译检索表。所用全色型航空像片的比例尺是1:35000,而彩色红外型航空像片的比例尺是1:34000。     

浙江仙居俞坑森林群落特征研究

浙江省仙居县俞坑境内由于地形复杂 ,水热条件优越 ,加上以前交通不便 ,限制了人类的频繁活动 ,使原有的植物种类得以保存和发展。这是括苍山系仅存的一片次生湿润常绿阔叶林 ,属中亚热带低海拔地区典型的地带性植被。此地于 1991年建立了县级自然保护区 ,目前对该群落仅在演替方面作过研究[1] 。本文主要对该群落的特征进行研究 ,为这一类型的植被研究和资源保护提供资料。1　自然概况俞坑位于浙江省仙居县境内 ,距括苍山主峰米筛浪约 4 0ｋｍ ,为括苍山尾部。地理位置为 2 8°0′5″Ｎ、12 0°0′5″Ｅ ,面积约 3ｋｍ2 [2 ] ,海拔高度在 4…     

承德市避暑山庄植被生态规划有关问题的探讨

本文首先对避暑山庄现状植被及存在的问题进行研究,绘制了现状植被图;然后分析了旅游及城市化对避暑山庄土壤及植物的影响程度以及不同生境土壤中N,P、K、有机质、水分含量及pH大小,针对避暑山庄不同游览区存在的植物配置不协调、生境不适、环境污染等问题,从植被生态角度出发对避暑山庄进行了规划和设计,最后完成了1:10000规划植被图。     

沈阳市建成区行道树的结构与功能研究

城市森林不仅可以减少城市中的裸露地面 ,更是大气污染的天然净化器。它可以促使大气中Ｏ2和ＣＯ2 的平衡 ,降低多种有害气体浓度 ,吸附空气中的灰尘[3] 。沈阳市是一个重工业城市 ,由于历史和现实的原因 ,以工矿企业污染物排放为主要污染源的大气污染日益严重。因此 ,城市森林的建设对于减轻城市大气污染至关重要。行道树是城市森林的重要组成部分 ,是连接城市分段隔离绿地的纽带 ,同时又为野生动物提供了栖息地及迁移通道 ,被认为是城市自然恢复的重要手段 ,其功能越来越受到人们的重视[8] 。怎样合理配置行道树的结构 ,发挥其最大生态效…     

彩叶植物漫谈

近年来我国从国外引进了许多彩叶植物,它们具有花朵一样绚丽的色彩,在春季盛花期过后与绿叶植物相互映衬,极大地丰富了城市的色彩,而且枝繁叶茂,易于形成大面积的群体景观,可在城市绿化中发挥点、线、面的作用,因此成为目前园林绿化美化的新宠。关于彩叶植物的定义,从狭义上说,彩叶植物不包括秋色叶植物,在春秋两季甚至春夏秋三季均呈现彩色,尤其在夏季旺盛生长的季节仍保持彩色不变,一些彩叶裸子植物及亚热带地区的彩叶植物甚至终年保持彩色。它们与传统的仅在秋季变色的秋色叶植物很不相同,且呈现色叶的机理也不尽相同。广义…     

上海市城市绿地景观空间格局研究

以上海市为研究区域,以遥感与地理信息系统为技术手段,基于2003年航空影像,分别按照景观类型和斑块大小两方面对城市绿地景观进行了类型划分,建立了城市绿地景观空间数据库;并将研究区域划分为8个空间单元,运用景观生态学以及空间分析方法,分别从斑块水平、类型水平、景观镶嵌结构等方面研究了上海市城市绿地景观格局的总体布局特征;选择斑块数量、斑块面积标准差、面积均值、周长均值、分维数等若干景观生态学指数来研究城市绿地景观镶嵌结构的数量特征,探讨了城市绿地景观在城市扩展与城市景观格局演变过程中所呈现的时空规律,旨在为城市规划与发展提供决策依据。     

A Comparison of Remote Sensing and Ground-Based Methods for Monitoring Wetland Restoration Success

Abstract Efficient and accurate vegetation sampling techniques are essential for the assessment of wetland restoration success. Remotely acquired data, used extensively in many locations, have not been widely used to monitor restored wetlands. We compared three different vegetation sampling techniques to determine the accuracy associated with each method when used to determine species composition and cover in restored Pacific coast wetlands dominated by Salicornia virginica (perennial pickleweed). Two ground‐based techniques, using quadrat and line intercept sampling, and a remote sensing technique, using low altitude, high resolution, color and color infrared photographs, were applied to estimate cover in three small restoration sites. The remote technique provided an accurate and efficient means of sampling vegetation cover, but individual species could not be identified, precluding estimates of species density and distribution. Aerial photography was determined to be an effective tool for vegetation monitoring of simple (i.e., single‐species) habitat types or when species identities are not important (e.g., when vegetation is developing on a new restoration site). The efficiency associated with these vegetation sampling techniques was dependent on the scale of the assessment, with aerial photography more efficient than ground‐based sampling methods for assessing large areas. However, the inability of aerial photography to identify individual species, especially mixed‐species stands common in southern California salt marshes, limits its usefulness for monitoring restoration success. A combination of aerial photography and ground‐based methods may be the most effective means of monitoring the success of large wetland restoration projects.     

基于遥感影像的城市空间三维绿量(绿化三维量)定量研究

三维绿量又称绿化三维量,是指所有生长植物的茎叶所占据的空间体积。城市三维绿量的测量研究是城市绿化环境效益评价的基本前提,也是城市生态系统研究的重要内容之一。以彩红外航空遥感图像为主要信息源,研究了城市空间三维绿量定量计算的方法。在对植被遥感阴影图像分割的前提下,根据航空摄影时太阳、摄影机以及树木三者之间的几何位置关系,建立了空间三维绿量遥感中关键的植被高度模型。应用统计分析方法,建立了研究区主要树种的树高一冠径相关关系模型。根据冠径一冠高关系以及典型树种的树冠立体几何形态与绿量方程,运用G1S分别计算了浙江省宁波市江北区、江东区、海曙区和全市的总三维绿量和平均相对三维绿量,以及平均相对三维绿量的区域分布。宁波市全市及江北区、海曙区和江东区的平均相对三维绿量分别为3284．4m^3／hm^2、3652．4m^3／hm^2、2908．5m^3／hm^2和3229．7m^3／hm^2,总三维绿量分别为1606．6万m^3、659．5万m^3、448．9万m^3和498．2万m^3。研究结果不仅为城市绿化数据库的建立奠定了基础,而且还丰富了城市绿化评价指标,有助于估算城市绿化的生态环境效益,以及为城市绿化系统的设计,特别是为环境要求不同的功能区的绿化系统的设计、城市绿化群落布局的合理性评价和城市绿化规划提供有价值的技术参数。     

The Ethnography of Landscape: GIS and Remote Sensing in the Study of Forest Change in West African Guinea Savanna

In this paper we explore the application of Amazonian forest change models to the Guinea savanna environment of western Africa. In particular, we examine recent research documenting the growth of peri-village forest islands in the area of Kissidougou, Guinea, which purports to challenge the pervasive view of Guinea savanna deforestation brought about by human activity. As a more systematic approach to the analysis of human/environmental interactions, we propose an "ethnography of landscape," in which the findings of detailed, local ethnographic and ecological case studies are combined with remotely sensed information on what the wider region looks like as it changes over time. In pursuing this research, we employ aerial photography and Geographic Information Systems (GIS) techniques to examine our study area of Kilimi in northwestern Sierra Leone. We show that a Kissidougou-type model of peri-village forest island growth is not applicable to this region, where other environmental change processes are underway. In future work, we propose to employ Landsat satellite image archives to examine, monitor, and compare processes of ecological change throughout the Guinea savanna. [deforestation, ecological anthropology, remote sensing, Sierra Leone, West Africa]     

History of kelp beds (Macrocystis) in Orange and San Diego Counties,California

Areas of Macrocystis canopies, as recorded by infrared aerial photography, are presented for about 140 km of the southern California coastline for the 25 year period 1967 to 1991. Several surveys per year were conducted and the largest size canopy per year was selected for presentation. Possible effects from various influences were examined: El Nino and La Nina episodes, storms, rainfall, and human-associated influences such as discharged wastewaters.     

A gradient analysis based on the buffer zones of urban landscape pattern of the constructed area in Guigang City, Guangxi, China

Over the last century urbanization on the landscape has increased and intensified. Urban development has a great impact on the environment at the local, regional and even global levels. As a driving force in global change, the need to understand the dynamics of urban pattern and its change in an accurate and efficient manner is ever more pressing. Based on aerial color infrared photography in 1985 and QuickBird satellite imagery in 2004 and according to the standard for plan and construction of city land use, the landscape of Guigang City was divided into 11 types. In the landscape classification maps, 31 buffer zones, each being 200 m wide, were divided. With the aid of GIS software ArcView 3.2 and landscape pattern analysis software FRAGSTATS 3.3, the landscape spatial patterns of each buffer zone were analyzed at the landscape level and class level. The landscape indices, such as patch size, patch fractal dimension, diversity index and evenness index, were calculated. The results indicated the following: The total area of the residential land and the communal land in 2004 covered 46.3% of the entire constructed area of Guigang City and the sum of the patch number of the two patch types occupied about 39.7% of the total patch number, while the percentages were respectively 48.2% and 45.4% in 1985. This showed that the mosaic landscape with the residential land and communal facilities land became increasingly unclear following urban development and landscape diversity. Based on the gradient analysis with the landscape-level index and the class-level index, there were two business and finance centers in the constructed area. One was located in the urban center with a range of 0.8 km; the other was from the 10^th to the 16^th zone. In each buffer zone, the mean patch size was larger and the landscape shape was more regular in 2004 than in 1985. Furthermore, the Shannon diversity index of each buffer zone rose in 2004 with patch richness and evenness increasing. The landscape index computed for the main landscape types (communal facilities land, industrial estate land, residential land and farmland) in the middle of the buffer zones clearly indicated the changes taking place in urbanization. The patch size and the patch number of industrial estate land and farmland also pointed to these changes, while communal facilities land and residential land assumed another similar tendency towards changes. In each gradient zone, industrial estate land had the most complex shape, the lowest area percentage of each zone and the biggest mean patch size, whereas communal facilities land and residential land were opposite to industrial estate land. Farmland had a steady percentage along the buffer zone and its continuous distribution had an important impact on the urban eco-environment. The question of how to relate the pattern of changing characteristics along the buffer zone to the urban ecological process and urban ecological planning remains to be studied further in the future.     

Estimation of walrus populations on sea ice with infrared imagery and aerial photography

Population sizes of ice‐associated pinnipeds have often been estimated with visual or photographic aerial surveys, but these methods require relatively slow speeds and low altitudes, limiting the area they can cover. Recent developments in infrared imagery and its integration with digital photography could allow substantially larger areas to be surveyed and more accurate enumeration of individuals, thereby solving major problems with previous survey methods. We conducted a trial survey in April 2003 to estimate the number of Pacific walruses (Odobenus rosmarus divergens) hauled out on sea ice around St. Lawrence Island, Alaska. The survey used high altitude infrared imagery to detect groups of walruses on strip transects. Low altitude digital photography was used to determine the number of walruses in a sample of detected groups and calibrate the infrared imagery for estimating the total number of walruses. We propose a survey design incorporating this approach with satellite radio telemetry to estimate the proportion of the population in the water and additional low‐level flights to estimate the proportion of the hauled‐out population in groups too small to be detected in the infrared imagery. We believe that this approach offers the potential for obtaining reliable population estimates for walruses and other ice‐associated pinnipeds.     

Riparian monitoring using 2-cm GSD aerial photography

Riparian monitoring is a key aspect of sustainable resource management and is mandated by US federal law for federal land management agencies. However, it is an endeavor hampered by rising manpower costs and time-consuming travel and methods. These limitations tend to reduce sampling intensity per reach of stream and limit monitoring to the larger waterways of management units—limitations that reduce the accuracy of inferences derived from resulting data with consequential reductions in the effectiveness of landscape-level resource management. We tested the utility of low-altitude, high-resolution, intermittent aerial digital imagery for relatively inexpensive, high-intensity sampling in a watershed inhabited by the Lahonton Cutthroat trout, a species listed as threatened under provisions of the US Endangered Species Act. Measurements gleaned from the aerial imagery included late-summer open water width, number and location of late-summer dry channels, widths of riparian areas and willow coverage. All measurements were georeferenced to allow spatial data display. Riparian proper functioning condition (PFC) was assessed from the imagery by a USDI, Bureau of Land Management team. These assessments were compared to similar on-the-ground assessments made during the preceding year. PFC assessments from aerial photography were made using an average 4 staff hours per stream compared to an estimated 36 staff hours per stream for ground PFC assessments. The two assessment methods yielded roughly comparable results. We conclude that riparian-condition assessments from 2-cm GSD digital aerial imagery allowed increased sample intensity (and thus increased inference accuracy) and that it did so in our study at a cost less than half that of conventional ground-based methods. We recommend the acquisition and analysis of 2-cm GSD digital aerial imagery be further trialed for its utility and cost efficiency in ecological monitoring of riparian systems.     

Comparison of census methods for black-browed albatrosses breeding at the Ildefonso Archipelago,Chile

A breeding population of black-browed albatrosses has been known to exist at the Ildefonso Archipelago, Chile, for >90 years but the population has never been censused using scientifically defendable methods. To estimate population size, and examine the accuracy and practicality of various census methods, the population was censused in the 2002/2003 breeding season using (a) ground-truthed aerial photography, (b) yacht-based photography, (c) ground counts, (d) quadrat sampling and (e) point-distance sampling. Compared to ground-truthed aerial photography (judged the most accurate) yacht-based photography underestimated population size by 55%, ground counts by 13%, quadrat sampling by 11% and point-distance sampling by 9%. Ground-truthed air photography revealed that in the 2002/2003 breeding season 47,000 pairs of black-browed albatrosses bred at the Ildefonso Archipelago. A repeat aerial census in 2006 suggested the size of the breeding population had not changed in the 4 years between the two censuses. After the Falkland Islands/Islas Malvinas, South Georgia and Diego Ramirez, the Ildefonso Archipelago holds the fourth largest population of black-browed albatrosses in the world.