Patch analysis指数简单对译.doc

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 landcapes 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 ImportantIn 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 its border are made up of a single patch. Its 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 patchs 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 patchs 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 its 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). Shannons Diversity Index (SDI) Measure of relative patch diversity. Shannons 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. Simpsons Diversity Index (SIDI)Measure of relative patch diversity. Simpsons 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. Shannons Evenness Index (SEI) Measure of patch distribution and abundance. Shannons 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. Shannons evenness index is only available at the landscape level. Simpsons 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 Simpsons 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 Simpsons 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 Simpsons Diversity Index (MSIDI) rather than the Simpsons Diversity Index (SIDI). ImportantDirect 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.度量定义（从McGarigal和标志，1995年，1994年和McGarigal和标记）类区（CA）属于一个给定的类的所有斑块的区域总和。例如：针叶类区（CA）= 359047.844 + . 65819.984CA =69.6626公顷的如果不指定地图单位（即数据帧的属性，请参阅设置地图单位）和“国家公顷”没有被选中的“空间统计”对话框中的“高级选项”，然后将统计结果将报告在本机地图单位（矢量图层（主题）。在本例中，CA = 696626.012（图）。这是对于大多数统计数据的情况下。风景名胜区（TLA）领域的所有斑块的景观总和。例：风景名胜区（TLA）= 46872.719 359047.844 + . + 62423.574TLA =184.11公顷的百分比景观（ZLAND）按类别分析时，ZLAND是由对应的类（贴片式）的总景观的百分比。斑块（NUMP）斑块总数的景观分析，如果“景观”，或为每个类的斑块数，如果选择“分析类”。例：级别：号码修补程序（NUMP的）Mixedwood = 5，康= 4，落叶= 5风景等级：斑块（NUMP）= 14景观丰富度（PR）公关是不同的斑块类型内的landcape的边界。景观丰富度密度（PRD）珠三角是等于PR除以景观总面积（米）的平方乘以10,000和100（转换为数百公顷）。最大斑块指数（LPI）LPI是等于是由最大的斑块的总景观。当整个景观是由一个单一的斑块，LPI等于100。的LPI作为最大斑块的大小减小，接近0。平均斑块面积（MPS）平均斑块大小。例如：平均斑块面积针叶修补程序（级别）MPS =（359047.844 139531.484 . 65819.984 +）/ 4MPS =17.42公顷的例：斑块（景观的平均斑块面积）（46872.719 + MPS = 359047.844 + . + 62432.574）/ 14MPS =13.15公顷的中位数斑块大小（MedPS）中间的斑块大小，或第50百分位。例如：平均斑块大小的康修补程序（级别）MedPS = 13.22公顷例：中位数的所有斑块（斑块大小景观的）MedPS = 7.59公顷斑块面积标准差（PSSD）斑块面积的标准偏差。例：斑块面积标准差针叶修补程序（级别）PSSD = 11.05公顷例如：修补尺寸标准偏差的所有斑块（山水水平）PSSD = 9.51公顷斑块大小变异系数（PSCoV）变异系数的斑块。例：康斑块的变异系数（职业等级）PSCoV = PSSD / MPS =（11.05公顷/17.42公顷的）* 100 = 63例：变异系数的所有斑块（景观水平）PSCoV =（9.51公顷/13.15公顷的）* 100 = 72总边缘（TE）周边的斑块。例：总边缘针叶树（级别）TE =总和，外围所有针叶树斑块的。TE =10858.88米的单位表示在本机地图单位。例：总边缘的修补程序（景观水平）TE =周长总和的所有斑块TE =28607.27米的重要在矢量图层（主题）的情况下，边缘计算包括所有的景观，包括边界边缘的边缘。对比的加权边缘特征的边界处的边的权重可以被设置为零。在栅格（网格）的层（主题）的情况下，边缘计算不包括的边缘周围的景观边界边缘或任何内部边缘，包括的像素分类为无资料。边缘密度（ED）金额相对于景观区的边缘。举例：边缘密度针叶树（级别）ED = TE / TLAED = 10858.88 metres/184.11公顷=58.98米的/公顷举例：边缘密度的所有斑块（景观水平）ED = 28607.27 metres/184.11公顷=155.38米的/公顷平均斑块边缘（MPE）平均每块边缘。例：平均斑块边缘康（级别）MPE = TE / NUMP的MPE =10858.88米/ 4斑块=2714.72米的/斑块例：平均斑块边缘的修补程序（景观水平）MPE = TE / NUMP的MPE = 28607.27 metres/14斑块=2043.38米的/斑块对比加权边缘密度（CWED）CWED边缘的密度是衡量在景观（米每公顷）与用户指定的对比度重量。CWED等于0时，有没有边缘的景观，换句话说，整个景观和它的边界是由一个单独的斑块。这是作为边缘的量的的景观增加和/或作为用户增加对比度重量的值增加。景观形状指数（LSI）LSI是景观边界和边界内的总景观面积（平方米）的平方根，除以一个常数（圆形标准的矢量图层，栅格）的平方标准调整所有的边缘。 LSI将增加，增加景观的形状不规则或边缘内的景观越来越多。双对数分形维数（DLFD）DLFD是斑块周长的复杂性的度量。接近1时，斑块形状是“简单”，如圆或正方形，它的大小接近2斑块形状边界复杂性的增加。平均周长面积比（MPAR）形状的复杂性。例如：平均周长面积比针叶树（级别）MPAR每一个斑块的斑块数量除以周长/面积比的总和。132米/公顷+ 112米/公顷+ 201米/公顷+ 84米/公顷：MPAR =（）/ 4片MPAR = 182米/公顷例：平均周长面积比所有的斑块（景观水平）MPAR =（200米/公顷+ 132米/公顷+ . + 175米/公顷）/ 14斑块MPAR = 185米/公顷平均形状指数（MSI）形状的复杂性。MSI是等于1时所有斑块是圆形的（多边形）或正方形（光栅（栅极）和增加的增加斑块形状不规则。MSI =总和的每个斑块的边界划分斑块面积（公顷）的平方根为每类（当分析按类别）或所有斑块时分析的景观，并调整为圆形标准（多边形），或方标准栅格（网格），除以斑块的数量。面积加权平均形状指数（AWMSI）AWMSI是等于1时所有斑块是圆形的（多边形）或正方形（光栅（栅极）和增加的增加斑块形状不规则。AWMSI等于每个斑块的周长总和，除以的平方根斑块面积（公顷）为每一个类（当分析按类别）或所有修补程序时分析的景观，并调整为圆形标准（多边形）或方形的标准栅格（网格），除以斑块的数量。它不同于MSI的，因为它的加权斑块面积较大的修补程序将重量超过规模较小的。平均斑块分形维数（MPFD）形状的复杂性。平均斑块分形的尺寸（MPFD）的形状复杂的又一举措。平均分