景观分析工具：arcgis中patch analysis模块
关键字：景观分析arcgis patch analysis 地理信息系统
转自：http://blog.sina.com.cn/s/blog_44b367b10100xt9m.html
模块下载地址：http://flash.lakeheadu.ca/~rrempel/patch/pa_Setup_v93.exe
模块安装步骤：
1. First uninstall any existing versions of Patch Analyst and then run the setup program (e.g., pa_Setup_v93.exe).
2. Open ArcMap, but note that on Windows 7 and Vista you must right click on the ArcMap icon, and "Run as Admin " in order to see the dlls and finish the final install steps, even if you are logged on to the computer as Admin. You probably also need to be logged on as Admin on Win XP.
3. Click on "Tools and select "Customize".
4. Click on the "Commands" tab.
5. Find "Menus" in the 'Categories' column and click on it.
6. - Click the "Add from file" button at the bottom.
- Navigate to the directory where Patch Analyst is stored (usually C:\Program Files\ArcGIS\extensions\PatchAnalyst).
- Select "PatchAnalystv93.dll".
- A window will appear showing the objects added. Click "OK".
- Repeat for PatchGridv93.dll
7. In the 'Commands' column (right hand side) click and drag and drop "Patch" (or "Patch Grid") onto the menu bar.
- When you move the item to an acceptable location (e.g. between Windows and Help menu items, a vertical bar will appear)
8. Open the tutoria data set map. Under File...Open, navigate to C:\Patch Analyst\Samplesand select Patch Analyst Sample Datav93.mxd
（按：大概由于现在所分析的数据空间尺度过大，导致fragstats运行无法分配内存，提示"cannot allocate memory"，尝试使用arcgis的景观分析模块，正在探索中……）
原文地址http://flash.lakeheadu.ca/~rrempel/ecology/papers/patchanalyst.pdf
什么是ARCGIS ® 斑块分析师？
斑块分析师是ArcGIS ®软件系统扩展模块，有利于景观斑块的空间分析与建模与修补程序相关的属性。它是用来进行空间格局分析，常栖息地建模，生物多样性保护和森林管理的支持。该方案包括能力的特点补丁模式和分配能力补丁的价值观基础上的补丁属性（例如立场年龄，林冠组成和冠封闭组合）的组合。它有两个版本，斑块和栅格斑块;后者是栅格分析，而前者是用于多边形层。
Patch analyst is an extension to the ArcGIS®software system that facilitates the spatial analysis of landscape patches and the modeling of attributes associated with patches. It is used for spatial pattern analysis, often in support of habitat modeling, biodiversity conservation and forest management. The program includes capabilities to characterize patch pattern and the ability to assign patch values based on combinations of patch attributes (e.g. combinations of stand age, overstory composition and crown closure). It is available in two versions, Patch and Patch grid; the former is used with polygon layers while the latter is for raster (grid) layers.
它如何工作的？
•一旦程序下载，并添加到ArcGIS工具栏，用户只需点击修补或修补网格显示下拉菜单一拉。如果相关数据（例如，栅格文件对应于Patch Grid）不是当前地图的一部分，有关数据类型的属性选项将不可用，并且在菜单上显示为灰色。
Once the program is downloaded and added to the ArcGIS toolbar the user simply clicks on Patch or
Patch Grid to reveal a pull down menu. If relevant data (e.g. a raster file for Patch Grid) is not a part of the current map, options pertaining to that data type will be unavailable and appear faded on the menu.
•各种可用的操作，允许用户：按字段dissolve（簇）和重分类多边形或栅格，相交（合并）层，建立核心领域，六边形区域，添加或刷新面积和周长字段，从FRI字符串字段创建变量以及对图层中的数据进行各种空间统计参数。
A variety of available operations allow the user to: dissolve (clump) and re-class polygons or rasters by fields, intersect (combine) layers, create core areas, make hexagon regions, add or refresh area and perimeter fields, make variables from FRI string fields as well as calculate a variety of spatial statistics on the data in the layers.
•栅格和多边形图层的空间的的计算是不同的，因此是一个"空间统计"的实现要涉及patch analyst 和 patch grid两个模块。
The Spatial Analysis statistics for raster and polygon layers are calculated differently and therefore there is a 'Spatial Statistics' selection on both the Patch Analyst and Patch Grid menus.
•某些功能有所不同，取决于是否多边形或栅格文件。例如，patch模块的Dissolve功能直接使用了ArcGIS ®的Dissolve工具，而在栅格模块中是将相邻类似像元合并在一起。。
Some functions differ depending on whether the layer is a polygon or raster file. For example, the dissolve function in Patch Analyst uses the Dissolve tool in ArcGIS®, while in Patch Grid the tool clumps adjacent like pixels together.
两个模块中相交 Intersect（合并combine）命令也以不同的方式工作。在多边形斑块分析模块进行多边形相交分析时，使用ArcGIS ®的Intersect工具，在栅格斑块分析模块使用另一种针对栅格图层的算法。
The Intersect (combine) command also works differently in Patch Analyst and Patch Grid. When intersecting polygons in Patch Analyst, the ArcGIS® Intersect tool is used and Patch Grid uses a different method for raster layers.
批量及区域分析
BATCH AND REGIONS ANALYSIS
可以自动进行批量分析或区域分析。批量分析将对预先选定的shapefile文件分别进行单独分析。区域分析将一个大的分析图层细分成许多区域，并分析每个更小的分析单位。这些区域可以是行政区，生态区或任意区域，并可以包括行政区域，流域，或六边形网格叠加。斑块分析师提供了一个便于产生六边形叠加的工具，这些叠加可与原来的分析层相交。
Analysis can be automated by using either batch analysis or regions analysis. Batch analysis will run separate analyses on pre-selected shapefiles. Regions analysis is used where a single large analysis layer is subdivided into regions, and analysis is desired on each of these maller analysis units. Regions can be administrative, ecological or arbitrary, and can include such things as administrative districts, watersheds, or a hexagon grid overlay. Patch Analyst provides a facility to generate a hexagon overlay, and this overlay can be intersected with the original analysis layer.
对栅格数据的斑块分析
从栅格数据创建斑块主题是创建一个新图层（主题），每类像素簇被指定其面积和周长。这是斑块分析的一个必要步骤。
Create Patch Theme from Grid creates a new layer (theme), where each clump of like-classified pixels is assigned its own area and perimeter. This is a necessary step for patch analysis.
聚集栅格（网格）（与shiape文件的dissolve类似）很复杂，需要对运行过程多加注意。对栅格数据执行景观形状分析经常比对shape文件执行该过程要快。聚集栅格（网格）并不是必要步骤，因为这是Fragstats的常规任务。但是，聚簇需要同一类型的每个斑块信息（即制作斑块直方图）。当从shape file 或 coverage文件创建栅格（网格）时，将提示用户输入要素字段，并用它来创建栅格（网格），聚簇的方法（见下文）以及存储栅格（网格）文件的位置。其结果是输出了带有要素属性表的栅格（网格）数据。属性表中每种类型一行。为了绘制斑块直方图，计算斑块数量，一个类型中的每一斑块都需要用一行进行表示（邻接的像素簇）。解散栅格（网格）将简化表，并对每个斑块创建行。
Clumping rasters (grids) (analogous with dissolve for shape files) is complex and requires that careful attention be paid to the process. Performing a landscape pattern analysis on a raster (grid) file is often faster than on a shape file. Clumping rasters (grids) is not necessary when performing a spatial analysis in Patch Grid because this is done by the Fragstats routine. However, clumping is required when information for each patch within the same class is needed (i.e., producing patch histograms). When creating a raster (grid) from a shape file or coverage, the user is prompted for the feature field to use to create the raster (grid), the clumping method (see below), and the location to store the raster (grid). The result is a raster (grid) with a table of feature attributes. The table contains one row for each class. To produce patch histograms, calculate the number of patches etc., a row is needed for each patch (contiguous clump of pixels) within each class. Dissolving a raster (grid) will simplify the table and create a row for each patch.
注意：在解散栅格（网格）时会提示选择一种聚簇方法。
Note: When dissolving a raster (grid) you will be asked to select a Clumping Method.
4N和8N之间的区别是聚簇邻接像素的邻居（N）数量。例如，在下面的例子中有两个斑块A和B（白色像元）。如果4N - 使用直角方法被选中，每个像素周围搜索将包括每个像素的四边。任何临边的具有相同值的像素被发现，两个像素将被聚簇在一起。在下面的例子是使用4N-直角方法产生的两个不同的斑块（斑块A和斑块B）。相反，如果8N - 使用对角线被选中的搜索将包括每个像素的四边和对角线上的每个像素，或每个周围的像素，因此八个邻居。在这个例子中，如使用8N - 使用对角线法定义则将只有一个包括所有白色像素的单独斑块。
The difference between 4N and 8N is the number of neighbours (N) used in clumping contiguous pixels. For instance, in the example below, two patches are present, A and B (white cells). If 4N - Use Orthogonals is selected, a search around each pixel will include the four sides of each pixel. If a pixel with the same value is found on any of the four sides of pixel, the two pixels will be clumped together. In the example below there are two distinct patches when the 4N - Use Orthogonals method is used (Patch A and Patch B). In contrast, if 8N - Use Diagonals is selected the searches will include the four sides of each pixel and the diagonals of each pixel, or each surrounding pixel, hence eight neighbours. In the example, only one discrete patch would be defined using the 8N - Use Diagonals method, and it would include all the white pixels
解散栅格的步骤：
To dissolve a raster (grid):
Select the desired raster (grid) to dissolve from the ArcMap table of contents.
- Choose Create Patch Theme from Grid from the Patch Grid menu .
- Choose the field to clump by and then click OK.
- Select the Clumping Method (4N - Use orthogonals or 8N - Use Diagonals) and then clickOK and the tool will execute. For more information on Clumping Method refer to Create Patch Theme from Grid.
叠加（合并）栅格
Intersect (Combine) Grids
相交（合并）栅格允许用户对栅格图层进行叠加，尤其适用于叠加六边形图层（在斑块图层被转换为栅格格式后）。
Intersect (Combine) Grids allows users to intersect raster (grid) layers (themes), and is especially useful to intersect the hexagon layer (theme) (once its been converted to raster (grid) format) with a specified patch layer (theme).
叠加（合并）栅格教程
Intersect (Combine) Grids Tutorial
- Intersecting grids is often the first step for Analysis by Regions. To combine to raster (grid) layers (themes) into one layer (theme) select Intersect (Combine) Grids from the Patch Grid Menu.
- Choose the first raster (grid) from the pull down menu of available layers (themes) and click OK.
- Choose the second raster (grid) from the pull down menu of remaining available layers (themes) and click OK.
- The user will then be prompted for a name and location of the new layer (theme) that will be created. Once that is done and the user clicks Save the rasters (grids) will be combined.
将栅格剪辑为多边形主题
Clip Grids to Polygon Theme
此功能将栅格（网格）剪辑为一个多边形图层（主题）。它不同于其他arcgis中你可以找到的类似程序，将新栅格的大小以剪辑的多边形图层大小来定义。其结果是栅格文件占用的空间被大幅度减小，尤其是是由Fragstats导出的栅格文件。使用此功能可能会解决遇到Fragstats引擎输入栅格数据文件的大小限制发生的诸如"Fragstats输出文件未找到"或其他Fragstats错误。
This function will clip a raster (grid) to a polygon layer (theme). It differs from other similar procedures you might find in ArcGIS in that the extents of the new grid is defined by the extents of the clip polygon theme. This results in a considerable reduction in the size of the grid, and especially the exported grid file that is used by Fragstats. Using this function may resolve many of of the "Fragstats Output File Not Found" or other Fragstats errors encountered, as the Fragstats engine is limited by the size of the input raster data file.
剪辑栅格为多边形教程
Clip Grids to Polygon Theme Tutorial
- To clip a raster (grid) to a polygon layer (theme) select Clip Grids to Polygon Themefrom the Patch Grid Menu. A dialog box with a pull-down menu containing all available raster (grid) layers (themes) (i.e. on the current map) will open.
- Choose the raster (grid) layer (theme) that is to be clipped and click OK. The next dialog box to appear will contain a list of all possible polygon layers (themes) that can be used to clip the raster (grid). Choose one and click OK.
- The user will then be prompted for a name and a location (drive path) for the new layer (theme) to be saved. Once the file name is entered and the user clicks Save, the tool will execute and clip the raster (grid) to the polygon layer (theme)。
空间分析（fragstats界面）
Spatial Statistics (FragStats Interface)
从patch grid 菜单选择Spatial Statistics (FragStats Interface)菜单项打开界面。
Selecting Spatial Statistics (FragStats Interface) from the Patch Grid menu brings up the "Spatial Statistics" dialog box.
点击Run按钮时，选定的栅格将输出到系统临时目录，于是产生一个参数列表，Fragstats执行，然后生成的文件frag_av.class，frag_av.land和frag_av.full。这些临时的文本文件将被删除补丁电网与未来的执行，因此，如果你想保留原来的Fragstats输出，重命名文件是必要的。
When Run is clicked, the selected grid is exported to the system temporary directory, whereupon a parameter list is generated, Fragstats is executed, and then the files frag_av.class, frag_av.land, and frag_av.full are generated. These temporary text files are removed with the next execution of Patch Grid, therefore renaming the files is necessary if you wish to keep the original Fragstats output.
从这些统计数据读入ArcGIS中，并在用户指定的位置（如果输出表的名称和位置都没有指定，分析将无法运行）表中。根据被用来运行栅格（网格）图层的大小和计算机的速度，它可能需要几分钟时间，用户得到一个消息，说输出已成功创建。输出表将无法显示，直到收到这个确认消息。
Statistics from these are read into ArcGIS, and presented in a table in the location specified by the user (analysis will not run if an output table name and location are not specified). Depending on the speed of the computer being used to run Patch Grid and the size of the raster (grid) layer (theme) being analyzed, it may take a few minutes before the user gets a message saying that the output was created successfully. The output table will not be available for viewing until after this confirmation message is received.
以下是栅格数据空间统计的详细参数：
The following is a breakdown of the "Spatial Statistics for Grids" dialog box, one section at a time:
图层
Layers
这个图层窗口（左上角），ArcMap图层列表中的数据会显示为可选择。图层菜单中的每一个图层都可以作为分析数据。但每运行一次只能分析一个图层。选择需分析的图层。
In the Layers panel (top left), the layer(s) (theme) selected from ArcMap's table of contents will appear. Each layer (theme) that is present in the Layers menu can be analyzed; however, only one layer (theme) can be analyzed at a time. Select the layer (theme) that you wish to analyze.
类型
Class
类型框属性从选定图层的属性表中选择。
The Class box allows selection of the class field from the selected layer's attribute table to be analyzed. Both character and numeric classes can be analyzed.
分析
Analyze by
该参数用于选择在景观还是类型尺度上的统计计算。如图层需进行景观层面的分析，将对无论属于哪种类型的斑块或者单个值的数据都进行统计并生成报告。相反，在类型层面的分析时，统计结果只报告景观中每种类型的情况。
The Analyze By option allows calculation of spatial statistics at either the Landscape or Class level. If the layer (theme) is being analyzed at the landscape level, all patches, regardless of the class they belong to, will be analyzed and a single value will be reported for each statistic. In contrast, if the layer (theme) is analyzed at the class level, the statistics will be reported for each class within the landscape.
输出表格名称
Output Table Name
输出表的名称是输出表的名称（和驱动器的路径），将创建一个包含空间统计。如果该表已经存在，附加/覆盖选项将变为可用。默认是追加。
Output Table Name is the name (and drive path) of the output table that will be created containing the spatial statistics. If the table already exists, the Append/Overwrite options become available. The default is Append.
综合统计
General Statistics
栅格板块分析提供了6大类统计项：
There are six categories of statistics available in the Patch Grid Analyst:
- Area面积
- Patch Density and Size Metrics 斑块密度和大小
- Edge Metrics边缘
- Shape Metrics形状
- Diversity Metrics多样性
- Core Area Metrics核心区
只需选择要计算的，并在空间统计输出表中报告的统计数据。选择"选择所有"选择所有的统计信息，或选择"选择"无"，以明确的选择。某些统计数字只适用于在景观水平。同样，某些统计数字只适用多边形层（主题）。对于统计的适用性（多边形或栅格）和缩写可参见统计摘要（附注1）。
Simply select the statistics to be calculated and reported in the spatial statistics output table. Choose "Select All" to select all the statistics or choose "Select None" to clear the selection. Certain statistics are only applicable at the landscape level. Similarly, certain statistics are only applicable on polygon layers (themes). For a listing of statistic applicability (polygon or raster) and abbreviations refer to Statistic Summary.
Core Area核心区
只适用于栅格数据的空间统计对话框中的核心区度量。当要求对矢量图层进行核心区分析时，用户必须首先从patch 菜单建立核心区（创建一个核心区图层），然后把它当作一个正常的斑块图层的进行分析。从空间统计的对话中选择所需的统计项（即，平均斑块大小，等等），结果将是核心区的统计数据。在创建核心区层（主题）时会有两个字段添加到图层的属性表：I）的核心区面积 和II）斑块面积。然后可以确定选择适当的位置来对核心区图层进行统计分析。
Core Area Metrics from the spatial statistics dialog are only available for raster (grid) layers (themes). When core area statistics are required for vector layers (themes), the user must first Create Core Areas (create a core area layer (theme)) from the Patch menu and then treat the core area layer (theme) as a normal patch layer (theme). Choose the desired statistics (i.e., Mean Patch size, etc.) from the spatial statistics dialogue and the result will be core area statistics. When creating core area layers (themes) two fields are added to the layer's attribute table: i) Core Area and ii) Patch Area. Therefore be sure to choose the proper field to calculate statistics when analyzing core area layers (themes).
设置分析界限参数
Set Analysis Parameters
Fragstats还允许用户改变一些其他的分析参数，包括MPI的阈值，缓冲距离，文件名CWED，和边界的影响。这些参数的当前设置可以看出，在"分析参数"，"栅格数据空间统计"对话框的底部面板。要更改其中的任何设置，点击"设置分析参数"按钮。
Fragstats also allows the user to change some other analysis parameters including the MPI Threshold, Buffer Distance, CWED file name, and the Boundary Influence. The current settings of these parameters can be seen in the "Analysis Parameters" panel at the bottom of the "Spatial Statistics for Grids" dialog. To change any of these settings, click theSet Analysis Parameters button.
空间分析输出表格
Spatial Statistics Output Table
从景观格局分析创建的空间统计输出表中查看分析结果。无论分析栅格数据还是矢量图层，前四列/字段将永远是相同的。这四个字段分别为：i）数据名称，II）分析日期，III）运行（运行数）和 IV）类型（类统计代表某个特定的行）。如果是在景观水平上进行分析，类型字段将报告整体的。下面表中的字段包含"空间统计"对话框中选定的统计项。作为一个完整的清单，包括缩写和单位，参考统计项汇总表（附注1）。每个统计项的一个完整的定义，也可在函数定义（附注2）页面找到。
The spatial statistics output table created from a landscape pattern analysis contains the results of the analysis. The first four columns/fields will always be the same regardless of whether a raster (grid) or vector layer (theme) was analyzed. The four fields are: i) (the name of the layer (theme) analyzed), ii) Run Date (the date of the analysis), iii) Run (the Run number), and iv) Class ( the class that the statistics for a particular row represent). If an analysis is performed at the landscape level the Class field will report full. The following fields in the table will contain the statistics that were selected in the "Spatial Statistics" dialog box. For a complete listing including abbreviations and units that the statistics are reported in refer to the Statistic Summary table. A full definition of each statistic is also available on the Metric Definitions page.
输出表将作为一个dBASE IV（DBF）文件被保存到用户指定的位置。在程序运行前系统将提示用户指定输出表名称及其位置。
The output table will be saved as a dBase IV (.dbf) file and will be saved to the location predetermined by the user. The user will be prompted to name the output table and set it's location before the analysis will run.
附注1
Patch Analyst Statistic Summary
Statistic Name
Statistic
AbbreviationApplicable on
ShapeLayer (Theme)Applicable on
Raster (Grid) Layer (Theme)
Area Metrics
Class Area
CA
Y
Y
Total Landscape Area
TLA
Y
Y
Percentage of Landscape (%)
ZLAND
N
Y
Largest Patch Index (%)
LPI
N
Y
Patch Density & Size Metrics
No. of Patches
NumP
Y
Y
Mean Patch Size
MPS
Y
Y
Median Patch Size
MedPS
Y
N
Patch Size Coefficient of Variance
PSCoV
Y
Y
Patch Size Standard Deviation
PSSD
Y
Y
Patch Richness
PR
Patch Richness Density
PRD
Edge Metrics
Total Edge
TE
Y
Y
Edge Density
ED
Y
Y
Mean Patch Edge
MPE
Y
Y
Contrasted Weighted Edge Density
CWED
N
Y
Shape Metrics
Mean Shape Index
MSI
Y
Y
Area Weighted Mean Shape Index
AWMSI
Y
Y
Mean Perimeter-Area Ratio
MPAR
Y
N
Mean Patch Fractal Dimension
MPFD
Y
Y
Area Weighted Mean Patch Fractal Dimension
AWMPFD
Y
Y
Landscape Shape Index
LSI
N
Y
Double Log Fractal Dimension
DLFD
N
Y
Diversity & Interspersion Metrics
Mean Nearest Neighbour Distance
MNN
Y
Y
Mean Proximity Index
MPI
Y
Y
Interspersion Juxtaposition Index
IJI
Y
Y
Shannon's Diversity Index*
SDI
Y
Y
Shannon's Evenness Index*
SEI
Y
Y
Simpson's Diversity Index*
SIDI
N
Y
Simpson's Evenness Index
SIEI
N
Y
Modified Simpson's Diversity Index
MSIDI
N
Y
Core Area Metrics
Total Core Area
TCA
**
Y
Mean Core Area
MCA
**
Y
Core Area Standard Deviation
CASD
**
Y
Core Area Coefficient of Variance
CACOV
**
Y
Core Area Density
CAD
**
Y
Total Core Area Index
TCAI
**
Y
Core Area percent of Land (%)
C_LAND
N
Y
Number of Core Areas
NCA
N
Y
Mean Corea Area per patch (ha)
MCA1
N
Y
Patch Core Area Standard Deviation (ha)
CASD1
N
Y
Patch Core Area Coefficient of Variation (%)
CACV1
N
Y
Mean Core Area Index
MCAI
N
Y
Notes
All core area metrics are per disjunct cores.
* applicable only at the landscape level
** core area metrics are directly applicable for raster (grid) layers (themes). For vector layers (themes) create a core area layer (theme).附注2
Metric Definitions (from McGarigal and Marks, 1994 and McGarigal and Marks, 1995)
Class Area (CA)
Sum of areas of all patches belonging to a given class.
Example: Conifer Class Area (CA) = 359047.844+......+65819.984
CA = 69.6626 hectares
If the map units are not specified (i.e., Data Frame properties; see Set map units) and "State areas in Hectares" has not been selected in the "Advanced Options" of the "Spatial Statistics" dialog box, then the resulting statistics will be reported in native map units (vector layers (themes) only).
In the example; CA = 696626.012 (map units). This is the case for most statistics.
Landscape Area (TLA)
Sum of areas of all patches in the landscape.
Example: Landscape Area (TLA) = 46872.719 + 359047.844 +... + 62423.574
TLA = 184.11 hectares
Percentage of Landscape (ZLAND)
When analyzing by class, ZLAND is the percentage of the total landscape made up of the corresponding class (patch type).
Number of Patches (NumP)
Total number of patches in the landscape if "Analyze by Landscape" is selected, or Number of Patches for each individual class, if "Analyze by Class" is selected.
Example: Class Level: Number of Patches (NumP)
Mixedwood = 5, Conifer = 4, Deciduous = 5
Landscape Level: Number of Patches (NumP) = 14
Patch Richness (PR)
PR is the number of different patch types within the landcape's boundary.
Patch Richness Density (PRD)
PRD is equal to PR divided by the total area of the landscape (metres squared) multiplied by 10,000 and then 100 (to convert to hundreds of hectares).
Largest Patch Index (LPI)
The LPI is equal to the percent of the total landscape that is made up by the largest patch.
When the entire landscape is made up of a single patch, the LPI will equal 100. As the size of the largest patch decreases, the LPI approaches 0.
Mean Patch Size (MPS)
Average patch size.
Example: Mean Patch Size of Conifer Patches (Class Level)
MPS = (359047.844 + 139531.484 ...+ 65819.984)/4
MPS = 17.42 hectares
Example: Mean Patch Size of Patches (Landscape Level)
MPS = (46872.719 + 359047.844 + ... + 62432.574)/14
MPS = 13.15 hectares
Median Patch Size (MedPS)
The middle patch size, or 50th percentile.
Example: Median Patch size of Conifer Patches (Class Level)
MedPS = 13.22 hectares
Example: Median Patch size of all patches (Landscape Level)
MedPS = 7.59 hectares
Patch Size Standard Deviation (PSSD)
Standard Deviation of patch areas.
Example: Patch Size Standard Deviation of Conifer Patches (Class Level)
PSSD = 11.05 hectares
Example: Patch Size Standard Deviation of all patches (Landscape Level)
PSSD = 9.51 hectares
Patch Size Coefficient of Variance (PSCoV)
Coefficient of variation of patches.
Example: Coefficient of Variation of Conifer patches (Class Level)
PSCoV = PSSD/MPS = (11.05 hectares / 17.42 hectares) *100 = 63
Example: Coefficient of Variation of all patches (Landscape Level)
PSCoV = (9.51 hectares / 13.15 hectares)*100 =72
Total Edge (TE)
Perimeter of patches.
Example: Total Edge Conifer (Class Level)
TE = Sum of perimeter of all conifer patches.
TE = 10858.88 metres
Units are expressed in native maps units.
Example: Total Edge all patches (Landscape Level)
TE = Sum of perimeter of all patches
TE = 28607.27 metres
Important
In the case of vector layers (themes), edge calculations include all the edge on the landscape including boundary edge. The contrasted weighted edge feature allows edge weight at the boundaries to be set to zero. In the case of raster (grid) layers (themes), edge calculations do not include the edges that surround the landscape boundary edge or any interior edges that include pixels classified as No Data.
Edge Density (ED)
Amount of edge relative to the landscape area.
Example: Edge Density Conifer (Class Level)
ED = TE / TLA
ED = 10858.88 metres/184.11 hectares = 58.98 metres/hectare
Example: Edge Density of all Patches (Landscape Level)
ED = 28607.27 metres/184.11 hectares = 155.38 metres/hectare
Mean Patch Edge (MPE)
Average amount of edge per patch.
Example: Mean Patch Edge Conifer (Class Level)
MPE = TE / NumP
MPE = 10858.88 metres/4 patches = 2714.72 metres/patch
Example: Mean Patch Edge all Patches (Landscape Level)
MPE = TE / NumP
MPE = 28607.27 metres/14 patches = 2043.38 metres/patch
Contrasted Weighted Edge Density (CWED)
CWED is a measure of density of edge in a landscape (metres per hectare) with a user-specified contrast weight.
CWED is equal to 0 when there is no edge in the landscape, in other words the whole landscape and it's border are made up of a single patch. It's value increases as the amount of edge in the landscape increases and/or as the user increases the contrast weight.
Landscape Shape Index (LSI)
LSI is the total landscape boundary and all edge within the boundary divided by the square root of the total landscape area (square metres) and adjusted by a constant (circular standard for vector layers, square standard for rasters). The LSI will increase with increasing landscape shape irregularity or increasing amounts of edge within the landscape.
Double Log Fractal Dimension (DLFD)
DLFD is a measure of patch perimeter complexity. It nears 1 when patch shapes are 'simple', such as circles or squares and it approaches 2 as patch shape perimeter complexity increases.
Mean Perimeter-Area Ratio (MPAR)
Shape Complexity.
Example: Mean perimeter-area ratio Conifer (Class Level)
MPAR = Sum of each patches perimeter/area ratio divided by number of patches.
MPAR = (132 m/ha + 112 m/ha + 201 m/ha + 84 m/ha)/4 patches
MPAR = 182 metres/hectare
Example: Mean perimeter-area ratio all patches (Landscape Level)
MPAR = (200 m/ha + 132 m/ha + ... + 175 m/ha)/14 patches
MPAR = 185 metres/hectare
Mean Shape Index (MSI)
Shape Complexity.
MSI is equal to 1 when all patches are circular (for polygons) or square (for rasters (grids)) and it increases with increasing patch shape irregularity.
MSI = sum of each patch's perimeter divided by the square root of patch area (in hectares) for each class (when analyzing by class) or all patches (when analyzing by landscape), and adjusted for circular standard ( for polygons), or square standard (for rasters (grids)), divided by the number of patches.
Area Weighted Mean Shape Index (AWMSI)
AWMSI is equal to 1 when all patches are circular (for polygons) or square (for rasters (grids)) and it increases with increasing patch shape irregularity.
AWMSI equals the sum of each patch's perimeter, divided by the square root of patch area (in hectares) for each class (when analyzing by class) or for all patches (when analyzing by landscape), and adjusted for circular standard ( for polygons), or square standard (for rasters (grids)), divided by the number of patches. It differs from the MSI in that it's weighted by patch area so larger patches will weigh more than smaller ones.
Mean Patch Fractal Dimension (MPFD)
Shape Complexity.
Mean patch fractal dimension (MPFD) is another measure of shape complexity. Mean fractal dimension approaches one for shapes with simple perimeters and approaches two when shapes are more complex.
Area Weighted Mean Patch Fractal Dimension (AWMPFD)
Shape Complexity adjusted for shape size.
Area weighted mean patch fractal dimension is the same as mean patch fractal dimension with the addition of individual patch area weighting applied to each patch. Because larger patches tend to be more complex than smaller patches, this has the effect of determining patch complexity independent of its size. The unit of measure is the same as mean patch fractal dimension.
Mean Nearest Neighbor (MNN)
Measure of patch isolation.
The nearest neighbor distance of an individual patch is the shortest distance to a similar patch (edge to edge). The mean nearest neighbor distance is the average of these distances (metres) for individual classes at the class level and the mean of the class nearest neighbor distances at the landscape level.
Interspersion Juxtaposition Index (IJI)
Measure of patch adacency.
Approaches zero when the distribution of unique patch adjacencies becomes uneven and 100 when all patch types are equally adjacent.
Interspersion requires that the landscape be made up of a minimum of three classes. At the class level interspersion is a measure of relative interspersion of each class. At the landscape level it is a measure of the interspersion of the each patch in the landscape.
Mean Proximity Index (MPI)
Measure of the degree of isolation and fragmentation.
Mean proximity index is a measure of the degree of isolation and fragmentation of a patch. MPI uses the nearest neighbor statistic. The distance threshold default is 1,000,000. If MPI is required at specific distances, select Set MPI Threshold from the main Patch pull-down menu and enter a threshold distance.
Both MNN and MPI use the nearest neighbor statistic of similar polygons in their algorithm. Occasionally a blank or zero will be reported in MNN and MPI fields. This happens when one polygon vertex touches another polygons border but the two similar polygons do not share a common border. When this happens a manual edit (move) of the touching vertex will correct the problem in the layer (theme). This problem will not happen when analyzing raster (grid) layers (themes).
Shannon's Diversity Index (SDI)
Measure of relative patch diversity.
Shannon's diversity index is only available at the landscape level and is a relative measure of patch diversity. The index will equal zero when there is only one patch in the landscape and increases as the number of patch types or proportional distribution of patch types increases.
Simpson's Diversity Index (SIDI)
Measure of relative patch diversity.
Simpson's diversity index is only available at the landscape level and is a relative measure of patch diversity. The index will equal zero when there is only one patch in the landscape and increases as the number of patch types or proportional distribution of patch types increases.
Shannon's Evenness Index (SEI)
Measure of patch distribution and abundance.
Shannon's evenness index is equal to zero when the observed patch distribution is low and approaches one when the distribution of patch types becomes more even. Shannon's evenness index is only available at the landscape level.
Simpson's Evenness Index (SIEI)
SIEI is a measure of the distribution of area among patch types. It equals 1 when the distribution of area among patches is exactly even. SIEI approaches 0 as the distribution of area among the patches become more and more dominated by one patch type.
Modified Simpson's Diversity Index (MSIDI)
MSIDI is a measure of patch diversity. It equals zero when there is only one patch in the landscape and increases as the number of different patch types (PR) increases and the area among patch types becomes more equal.
Modified Simpson's Evenness Index (MSIEI)
MSIEI is a measure of the distribution of area among patch types. It equals 1 when the distribution of area among patches is exactly even. SIEI approaches 0 as the distribution of area among the patches become more and more dominated by one patch type. It differs from SIEI in that it is derived from the Modified Simpson's Diversity Index (MSIDI) rather than the Simpson's Diversity Index (SIDI).
Important
Direct analyses of Core Area through the spatial statistics dialogue are only available for raster (grid) layers (themes). If core area statistics are required for vector layers (themes), first Create Core Areas (create a new core area theme) from the Patch pull-down menu and then calculate statistics for the new layer (theme) as you would for a normal vector layer (theme). The results will be core area statistics.
Total Core Area (CA)
The total size of disjunct core patches.
The total size of disjunct core area patches (hectares).
Mean Core Area (MCA)
The average size of disjunct core patches.
The mean size of disjunct core area patches (hectares).
Number of Core Areas (NCA)
The total number of disjunct core areas within each patch of a corresponding patch type (or class).
Mean Core Area Index (MCAI)
MCAI is the average percentage of a landscape patch that is core area. It will be equal to 0 when there is no core area present in any patch in the landscape and it increases (towards 100%) when patches contain mostly core area.
Core Area Standard Deviation (CASD)
Measure of variability in core area size.
The standard deviation of disjunct core areas (hectares).
Core Area Density (CAD)
The relative number of disjunct core patches relative to the landscape area.
The total number of all disjunct patches divided by the landscape area (number of disjunct core patches/hectare).
Total Core Area Index (TCAI)
Measure of amount of core area in the landscape.
Total core area index is a measure of the amount of core area in the landscape. Total core area index is a proportion of core area in the entire landscape and is equal to zero when no patches in the landscape contain core and approaches one as the relative proportion of core area in the landscape increases.
Core Area Percentage of Land (C_LAND)
C_LAND is the percentage of the total landscape which is made up of core area.
Mean Core Area per Patch (MCA1)
MCA1 is the average core area per patch (as opposed to all distunct core areas).
It equals the sum of the core areas of each patch or corresponding patch type, divided by the number of total patches of the same type, divided by 10, 000 (to convert to hectares).
Core Area Coefficient of Variance (CACOV)
CACOV represents the variability in size of disjunct core areas in relation to the mean core area.
Patch Core Area Standard Deviation (CASD1)
Measure of variability in patch core area size.
The standard deviation of patch core areas (hectares).
Patch Core Area Coefficient of Variation (CACV1)
The standard deviation in core areas (CASD) divided by the mean core area per patch (MCA) and multplied by 100 (%).
The variablility in core area among patches relative to the mean core area.
