Largest Patch Index Research Articles

基于时空分析的生态保护与修复试点工程实施效果评估——以赣州市为例

PDF HTML阅读 XML下载 导出引用 引用提醒 基于时空分析的生态保护与修复试点工程实施效果评估——以赣州市为例 DOI: 10.5846/stxb201905291126 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 自然资源部国土整治中心课题（20191603） Evaluation on the implementation effect of the pilot project for ecological protection and restoration of multi ecological elements based on spatio-temporal analysis: A case study of Ganzhou Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以“山水林田湖草生命共同体”为中心思想，从生态系统的格局和质量两个方面，对赣州市山水林田湖生态保护与修复试点工程实施效果进行了综合评估。结果如下：（1）从生态系统格局来看，2015到2018年，赣州市森林、农田和城镇生态系统面积明显增加，超过40%的草地生态系统转变为森林生态系统，且近45%的城镇生态系统面积增量由草地生态系统贡献。此外，多数自然生态系统的斑块破碎化加剧，森林生态系统破碎化现象最为明显，最大斑块指数从54.36降低到37.41，而半自然生态系统最大斑块指数增大。（2）从生态系统质量来看，赣州市归一化植被指数稳定在0.7以上并呈增长趋势，水土流失综合治理面积从16543.8 km2增长到18550.4 km2，重点流域水质基本稳定在Ⅱ、Ⅲ级，城镇生态系统受土壤重金属污染的风险较小，但部分县区农田生态系统受一种或多种土壤重金属污染的风险较大。整体而言，赣州市山水林田湖生态保护与修复试点工程取得了显著成效，较好的完成了实施方案中的规划目标。在进一步的生态保护与修复工作中，应重视赣州市自然生态系统斑块破碎化严重地区、水质出现波动较大的河流断面以及农田生态系统受土壤重金属污染威胁较大的县区。 Abstract:From the perspective of the ecosystem pattern and quality, the effectiveness of the pilot project for ecological protection and restoration of multi ecological elements in Ganzhou was comprehensively evaluated based on the central idea of mountains-rivers-forests-farmlands-lakes-grasslands system as a community of life. The results are as follows:(1) For ecosystem pattern, the area of forest, farm and urban ecosystems in Ganzhou increased significantly. More than 40% of grassland ecosystems were converted to forest ecosystems, and nearly 45% of urban ecosystem area increment were contributed by grassland ecosystems. In addition, landscape fragmentation in most natural ecosystems was intensified, and the largest patch index (LPI) of forest ecosystems were decreased from 54.36 to 37.41, while the LPI in semi-natural ecosystems were increased. (2) Regarding ecosystem quality, the normalized difference vegetation index (NDVI) of Ganzhou was stable above 0.7 and showed an increasing trend. The comprehensive control area of soil erosion increased from 16543.8 km2 to 18550.4 km2, and the water quality in key river basins was basically stable at Grade II and III. For the quality of soil environment, urban ecosystems were less threatened by the risk of soil heavy metal pollution. But the soil of farm ecosystems in some areas were at higher risk of being contaminated by one or more heavy metals. Overall, the ecological protection and restoration project in Ganzhou has achieved remarkable effectiveness, and the planning objectives in the implementation plan have been well completed. In the further ecological restoration work, there are three problems should be taken seriously, including the natural ecosystems with severe landscape fragmentation, the rivers with large fluctuations in water quality, and the farm ecosystems with high risk of heavy metal pollution. 参考文献 相似文献 引证文献

Responses of stream water quality concentrations to vegetative cover variation in Muar River watershed

ABSTRACTAnalysis of the historical land-cover of Muar River watershed has shown that forest and agriculture are the dominant land-covers over the last three decades. This information was used to evaluate the relationship between the vegetative landscape variation to stream water quality concentrations which was to provide an insight for management of water quality under humid tropical climate. Three out of the six water quality variables simulated using the hydrological simulation program FORTRAN (HSPF) model are sensitive to change in vegetative land-covers which include; biochemical oxygen demand (BOD), nitrate-nitrogen (NO3-N), and orthophosphate (PO4) concentrations. However, total suspended solids (TSS), dissolved oxygen (DO), and ammonia-nitrogen (NH3-N) concentrations remain insensitive. Further analysis shows that patch density (PD) has a little impact on BOD, NO3-N, and PO4 concentrations compared to edge density (ED), largest patch index (LPI), and landscape shape index (LSI) under varied landscape conditions. However, large ED, LPI, and LSI indices in both forest and agriculture will result to increase in BOD, NO3-N, and PO4 concentrations. Therefore, adequate knowledge of the responses of the water quality concentrations to landscape pattern and its dynamics can serve as an alternative solution to stream water quality deterioration in an abundant rainfall region.

How to cool hot-humid (Asian) cities with urban trees? An optimal landscape size perspective

Urban areas typically experience higher temperatures compared to surrounding rural areas that is known as the urban heat island effect (UHI). Urban greenery is capable of mitigating the UHI by creating microclimates that are lower in temperature than their surroundings, which are known as urban cooling islands (UCI). Previous studies have proved the effectiveness of UCI from different perspectives. However, a specific optimal level of landscape patch size at a regional scale that can be implemented by urban planners has not been identified. In this study, we estimated the optimal patch size in seven selected hot-humid Asian cities with the help of Google Cloud Computing, Python Programming, as well as spatial and statistical analysis. A two-tier (two optimal patch sizes) distribution of the threshold value of efficiency (TVoE) of urban trees in this region was found. Eight landscape-level indexes were used to explore the variance of TVoE. The percentage of landscape (PLAND), edge density (ED), mean landscape shape index (Shape_MN), mean fractal dimension (FRAC_MN), largest patch index (LPI), and mean Euclidian nearest-neighbor distance (ENN_MN) were found to have no significant correlation with TVoE. While the average normalized difference vegetation index (NDVI_MN) and average background temperature (BGT_MN) were found to be highly associated with the variance in TVoE. Further, a concept model that can simulate the effects of NDVI_MN and BGT_MN was also proposed. These findings extend the understanding of the UCI effect of urban trees as well as providing a basis for scientific climate adaption planning in this region.

Relationship between landscape fragmentation and oasis evolution : a case study of Suzhou Oasis in arid China

Landscape fragmentation in arid area under the global Land Use/Cover Changehas drawn more attention in research of arid landscape ecology recently. In this study, the evaluated oasis evolution and its landscape fragmentation in Suzhou Oasis, a typical agricultural oasis in the middle reach of the Heihe River watershed. Oasis maps were obtained from Landsat TM images for 1990, 1999 and 2010, respectively. The results indicated that during 1990 to 2010, the change of oasis area was dominated by an increase of farmland, grassland and constructed land. The oasis area had increased mainly due to the conversion of farmland, unused land to grassland, and rapid urbanization. Landscape fragmentation index changed over time in the 15 towns, and there was a decrease of number of patches (NP), patch density (PD) and largest patch index (LPI), and an increase in division index (DIV) and Shannon’s density index (SHI), suggesting that the change of landscape fragmentation degree had slowed down gradually. An improved method is used to describe the villages and towns scales of landscape fragmentation of the oasis evolution and fragmentation process.

Land cover transition and fragmentation of River Ogba catchment in Benin City, Nigeria

This study examined variation in the intensity of land cover transition and the pattern of habitat fragmentation of River Ogba catchment. Landsat images of 1988, 2002 and 2016 were classified into five categories: low density urban, high density urban, mixed vegetation, agriculture and dense forest using maximum likelihood classifier. Intensity analysis approach and landscape metrics were used to analyze the changes and fragmentation of the land cover. Number of patches, largest patch Index, area-weighted shape index and Euclidean nearest neighbour were computed. The results show that although mixed vegetation accounted for the largest land cover category in 1988 and 2002, low density urban dominated the study area in 2016. Intensity analysis of land cover change in the study area indicates a rising trend. The urban fringe is observed to be highly dynamic zone and this is primarily driven by changes in agriculture, low density urban and mixed vegetation. The implications of rapid land cover transition and fragmentation in River Ogba catchment, and especially in the urban fringe, include threat to biodiversity, food supply and deteriorating environmental conditions. This study provides necessary insights for developing sustainable strategies for urban landscape planning, administration and governance.

Most suitable landscape patterns to preserve indigenous plant diversity affected by increasing urbanization: A case study of Shunyi District of Beijing, China

The effects of urbanization on plant diversity have been increasingly investigated around the world, but our knowledge of the performances of urbanized landscape is still inadequate for suitable urban landscape planning and management. We asked: 1) what are the effects of urbanized landscape pattern on indigenous plant diversity, and 2) do these effects exhibit scale dependence? A total of 105 plots, distributed throughout the study area were chosen. Each plot was 10 m × 10 m. Alpha-diversity, and beta-diversity of species taxonomic composition across plots was calculated. Four groups of landscape metrics (complexity, fragmentation, diversity, and urbanization intensity) were measured for each plot. Ten scales, ranging from 100 m to 1000 m and with increasing steps of 100 m, were used as spatial scales. Pearson’s correlation analyses were used to detect relationships between the indigenous plant diversity along the urbanization gradient and the ten landscape metrics. Shannon’s Diversity Index (SDI), Shannon’s Evenness Index (SEI), Edge Density (ED), and Landscape Shape Index (LSI) were highly and positively correlated with alpha and beta plant diversity, whereas Largest Patch Index (LPI) were negatively correlated with plant diversity. Such correlations became stronger at higher spatial scales, and the highest at 600–700 m. The intensity of urbanization increased the values of ED and LPI in urbanized landscape and negatively influenced plant diversity. The correlations were influenced by the spatial extent. The study offers some guidelines on landscape pattern, including patch size, shape, and its configuration, in managing urban areas optimally to support plant diversity and wildlife. Landscape unit with diverse land uses with a radius of 600–700 m for Beijing, and other specific radius for other cities in the world are proposed as the most suitable landscape pattern for preserving indigenous plant diversity.

Association of urban forest landscape characteristics with biomass and soil carbon stocks in Harbin City, Northeastern China

BackgroundUrban forests help in mitigating carbon emissions; however, their associations with landscape patterns are unclear. Understanding the associations would help us to evaluate urban forest ecological services and favor urban forest management via landscape regulations. We used Harbin, capital city of the northernmost province in China, as an example and hypothesized that the urban forests had different landscape metrics among different forest types, administrative districts, and urban–rural gradients, and these differences were closely associated with forest carbon sequestration in the biomass and soils.MethodsWe extracted the urban forest tree coverage area on the basis of 2 GF-1 remote sensing images and object-oriented based classification method. The analysis of forest landscape patterns and estimation of carbon storage were based on tree coverage data and 199 plots. We also examined the relationships between forest landscape metrics and carbon storage on the basis of forest types, administrative districts, ring roads, and history of urban settlements by using statistical methods.ResultsThe small patches covering an area of less than 0.5 ha accounted for 72.6% of all patches (average patch size, 0.31 ha). The mean patch size (AREA_MN) and largest patch index (LPI) were the highest in the landscape and relaxation forest and Songbei District. The landscape shape index (LSI) and number of patches linearly decreased along rural-urban gradients (p < 0.05). The tree biomass carbon storage varied from less than 10 thousand tons in the urban center (first ring road region and 100-year regions) to more than 100 thousand tons in the rural regions (fourth ring road and newly urbanized regions). In the same urban–rural gradients, soil carbon storage varied from less than five thousand tons in the urban centers to 73–103 thousand tons in the rural regions. The association analysis indicated that the total forest area was the key factor that regulates total carbon storage in trees and soils. However, in the case of carbon density (ton ha−1), AREA_MN was strongly associated with tree biomass carbon, and soil carbon density was negatively related to LSI (p < 0.01) and AREA_MN (p < 0.05), but positively related to LPI (p < 0.05).DiscussionThe urban forests were more fragmented in Harbin than in other provincial cities in Northeastern China, as shown by the smaller patch size, more complex patch shape, and larger patch density. The decrease in LSI along the rural-urban gradients may contribute to the forest carbon sequestrations in downtown regions, particularly underground soil carbon accumulation, and the increasing patch size may benefit tree carbon sequestration. Our findings help us to understand how forest landscape metrics are associated with carbon storage function. These findings related to urban forest design may maximize forest carbon sequestration services and facilitate in precisely estimating the forest carbon sink.

Evaluation of the relationship between soil erosion and landscape metrics across Gorgan Watershed in northern Iran.

Soil erosion is one of the most serious environmental threats strongly influenced by the spatial pattern of land uses. This study was designed to evaluate the relevance of land use pattern and soil erosion using landscape metrics across Gorgan Watershed in northern Iran. Therefore, the revised universal soil loss equation was applied to evaluate and model soil loss and sedimentation in the region. Then, soil erosion relationship to land use pattern was analyzed using a variety of metrics including percentage of landscape, number of patches, largest patch index, and landscape shape index. The results revealed that potential of soil loss, sediment retention, and sediment yield for the whole watershed were 6.6, 2.4, and 1.5tha-1year-1, respectively. The quantity of sediment retention was estimated at 4.3, 3.2, 1.0, and 1.2tha-1year-1 in forest, rangelands, agriculture, and built-up areas, respectively. Similarly, sediment yield was 0.6, 1.6, 1.5, and 2.1tha-1year-1, respectively. The results revealed that the soil loss increased with decreasing metrics of forest and rangelands while increasing metrics of built-up regions and agricultural lands accelerated the process. Moreover, we showed that land use type of patches was an important factor on soil erosion, and soil loss was also affected by area, number, shape, and density of landscape patches. Result of this study can facilitate monitoring of erosion-sensitive areas in the watershed which can help managers and decision makers to design more suitable measures for soil conservation.

Comparison of Landscape Metrics for Three Different Level Land Cover/Land Use Maps

This research aims to investigate how different landscape metrics are affected by the enhancement of the thematic classes in land cover/land use (LC/LU) maps. For this aim, three different LC/LU maps based on three different levels of CORINE (Coordination of Information on The Environment) nomenclature were created for the selected study area using GEOBIA (Geographic Object Based Image Analysis) techniques. First, second and third level LC/LU maps of the study area have five, thirteen and twenty-seven hierarchical thematic classes, respectively. High-resolution Spot 7 images with 1.5 m spatial resolution were used as the main Earth Observation data to create LC/LU maps. Additional geospatial data from open sources (OpenStreetMap and Wikimapia) were also integrated to the classification in order to identify some of the 2nd and 3rd level LC/LU classes. Classification procedure was initially conducted for Level 3 classes in which we developed decision trees to be used in object-based classification. Afterwards, Level 3 classes were merged to create Level 2 LC/LU map and then Level 2 classes were merged to create the Level 1 LC/LU map according to CORINE nomenclature. The accuracy of Level 1, Level 2, Level 3 maps are calculated as; 93.50%, 89.00%, 85.50% respectively. At the last stage, several landscape metrics such as Number of Patch (NP), Edge Density (ED), Largest Patch Index (LPI), Euclidean Nearest Neighbor Distance (ENN), Splitting Index (SPLIT) and Aggregation Index (AI) metrics and others were calculated for different level LC/LU maps and landscape metrics values were compared to analyze the impact of changing thematic details on landscape metrics. Our results show that, increasing the thematic detail allows landscape characteristics to be defined more precisely and ensure comprehensive assessment of cause and effect relationships between classes.

Grassland fragmentation and its influence on woody plant cover in the southern Great Plains, USA

Woodland and agricultural expansion are major causes of grassland fragmentation. Fire and rainfall play important roles in maintaining grasslands, however, fire activity has been reduced in fragmented landscapes. Quantify the degree to which basic landscape fragmentation metrics could be used as drivers of woody cover potential. Woody plant percent cover was calculated between 2004 and 2008 at > 2000 sites. At each site, we calculated these fragmentation metrics for grassland cover type (classified by the National Land Cover Database); # patches, landscape proportion, edge density, largest patch index, effective mesh size and patch cohesion index within 3 circular areas (10 km2, 360 km2 and 3600 km2) surrounding the sampling site. A quantile regression was performed to identify which metrics were useful at predicting the 25th, 50th, 75th or 95th quantile of woody cover distribution. Grassland proportion and edge density were significant predictors of the woody plant potential (75th and 95th quantile). Woody cover potential was positively associated with edge density suggesting that fragmented areas (i.e., areas with high number of edges) maintained higher woody cover, while grassland proportion was negatively associated with woody plant potential. We propose that in addition to a lack of fire, fragmented landscapes may facilitate further woodland expansion by reducing natural land and restricting grasslands to smaller, less connected patches, which can maintain higher woody cover. Given current trends in woodland expansion, special attention should be given to areas that are found within a fragmented landscape and climatically prone to woodland expansion.

Effects of spatio-temporal landscape patterns on land surface temperature: a case study of Xi'an city, China.

A city is a mixed ecosystem of nature, economy, and society and is simultaneously transforming natural areas and adapting to nature. Urbanization causes the population to expand rapidly, leading to rapid expansions of scale. Consequently, the proportions of impermeable surfaces (ISs) and greenspaces (GSs) change drastically, which has a considerable influence on the urban thermal environment. The aim of this study was to research the effects of spatio-temporal landscape patterns on land surface temperature (LST) and between GS and IS in the city of Xi'an using the urban-rural gradient, the moving split-window algorithm (MSA), multiple grid resolutions, and landscape metrics based on three-phase Landsat data. The results showed that there was a significantly positively correlated with IS density and significantly negatively correlated with the GS density from the urban center to rural areas. Over the past 25years, the main urban area of Xi'an has expanded by nearly 6.2 times its initial size. The correlation between IS density and LST increased with increasing grid size, and the correlation between GS density and LST increased with decreasing grid size. Thus, LST is highly sensitive to the ISs and GSs at particular grid sizes. The correlation coefficients of the ISs and GSs with LST increased with decreasing grid size during 1992-2016. Hence, the LST was less sensitive to IS and the GS densities in conjunction with larger grid sizes. The class area (CA) and the landscape shape index (LSI) of the ISs were significantly positively correlated with the LST, whereas the CA and largest patch index (LPI) of the GSs were negatively correlated with the LST. The LST of the ISs in 1992, 2006, and 2016 were 1.6, 1.8, and 3.9°C higher, respectively, than those of the GSs, indicating that GSs are important to lowering urban LSTs. Therefore, the government and urban planning departments should consider optimizing the spatial patterns of ISs and GSs to fully exploit the cooling effect of optimally configured GSs, which would be conducive to the sustainable development of the urban ecological environment.

How China’s linked urban–rural construction land policy impacts rural landscape patterns: a simulation study in Tianjin, China

To prevent the area of arable land from crossing the limit of 120 million ha arable land red line, China’s government proposed a linked urban–rural construction land policy. This policy helps to protect the arable land but will impact the rural landscape. The objective is to evaluate the effect of the linked urban–rural construction land policy on rural landscape in the future. We performed a simulation method to predict the rural landscape pattern changes in Tianjin during 2005–2020 using a cellular automata and multi-agent system model under the scenarios with or without implementing this policy. The landscape metrics were calculated for both scenarios to find the effects caused by this policy. Following this policy, the Total Area and Large Patch Index of arable land decreased slowly. 65.50% of the occupied arable land can be compensated. For rural settlements, the Mean Patch Area increased to 2.87 times that in 2005. Number of Patches reduced greatly, and 1053 of the total rural settlements distributed along the periphery of Tianjin were reclaimed for arable land during 2005–2020. Aggregation Index increased greatly. According to the simulation model, the policy is effective on slowing down the loss of total arable land and the process of large arable land fragmentation. The increasing degree of aggregation of rural settlements is beneficial to the optimal allocation of resources and rural centralized management. However, as the rural settlements gather to urban construction land, they are more vulnerable to urban issues.

Impacts of Urban Sprawl on Soil Resources in the Changchun⁻Jilin Economic Zone, China, 2000⁻2015.

The Changchun–Jilin Economic Zone (CJEZ) is one of the most rapidly developing areas in Northeast China, as well as one of the famous golden maize belts in the world. This is a case study to assess the impacts of urban sprawl on soil resources using remote sensing imagery and geographic spatial analysis methods. The common urbanization intensity index (CUII), soil quality index, and soil landscape metrics were calculated to reflect urbanization and the response of soil resource. Results showed that the area of soil sealing changed from 112,460 ha in 2000 to 139,233 ha in 2015, and in the rural region, the area occupied by urbanization nearly kept balance with the area of rural residential expansion. Urban land increased by 26,767 ha at an annual rate of 3.23% from 2000 to 2015. All seven soil types were occupied during the urbanization process, among which black soil ranked the highest (18,560 ha) and accounted for 69.34% of the total occupied area. Soils of Grades I (3927 ha) and II (15,016 ha) were 64.75% of the total occupied soil areas. Urban land expanded in an irregular shape and a disordered way, which led to an increasing large patch index (LPI) and aggregation index (AI), and a decreasing edge density (ED) and Shannon’s diversity index (SHDI) of the soil landscape in the study area during 2000–2015. According to the geographically weighted regression (GWR) model analysis, the R2 between the CUII and soil landscape metrics decreased from the LPI and ED to SHDI and in turn to AI. The local R2 between SHDI, ED, and CUII showed a gradient structure from the inner city to peri-urban areas, in which larger values appeared with strongly intensive urbanization in urban fringes. Soil sealing induced by urbanization has become a significant factor threatening soil, the environment, and food security. How to coordinate regional development and ensure the sustainability of the multiple functions of soil is a problem that needs to be taken into account in the future development of the region.

Urbanization between compactness and dispersion: designing a spatial model for measuring 2D binary settlement landscape configurations

ABSTRACTMeasuring spatial patterns is a crucial task in spatial sciences. Multiple indicators have been developed to measure patterns in a quantitative manner. However, most comparative studies rely on relative comparisons, limiting their explanatory power to specific case studies. Motivated by advancements in earth observation providing unprecedented resolutions of settlement patterns, this paper suggests a measurement technique for spatial patterns to overcome the limits of relative comparisons. We design a model spanning a feature space based on two metrics – largest patch index and number of patches. The feature space is defined as ‘dispersion index’ and covers the entire spectrum of possible two-dimensional binary (settlement) patterns. The model configuration allows for an unambiguous ranking of each possible pattern with respect to spatial dispersion. As spatial resolutions of input data as well as selected areas of interest influence measurement results, we test dependencies within the model. Beyond, common other spatial metrics are selected for testing whether they allow unambiguous rankings. For scenarios, we apply the model to artificially generated patterns representing all possible configurations as well as to real-world settlement classifications differing in growth dynamics and patterns.

Post-War Land Cover Changes and Fragmentation in Halgurd Sakran National Park (HSNP), Kurdistan Region of Iraq

Context: The fundamental driving force of land use and land cover (LULC) change is related to spatial and temporal processes caused by human activities such as agricultural expansion and demographic change. Landscape metrics were used to analyze post-war changes in a rural mountain landscape, the protected area of Halgurd-Sakran National Park (HSNP) in north-east Iraq. Therefore, the present work attempts to identify the temporal trends of the most fragmented land cover types between two parts of the national park. Objectives: The objectives of this study are to compare two land cover classification algorithms, maximum likelihood classification (MLC) and random forest (RF) in the upper and lower parts of HSCZ, and to examine whether landscape configuration in the park has changed over time by comparing the fragmentation, connectivity and diversity of LULC classes. Methods: Two Landsat images were used to analyze LULC fragmentation and loss of habitat connectivity (before and after the Fall of Baghdad in 2003). Seven landscape pattern metrics, percentage of land (PLAND), number of patch (NP), largest patch index (LPI), mean patch size (MPS), euclidian nearest neighborhood distance (ENN_AM), interspersion and juxtaposition (IJI) and cohesion at class level were selected to assess landscape composition and configuration. Results: A significant change in LULC classes was noticed in the lower part of the park, especially for pasture, cultivated and forest-lands. The fragmentation trends and their changes were observed in both parts of the park, however, more were observed in the lower part. The inherent causes of these changes are the socio-economic factors created by the 1991–2003 UN post-war economic sanctions. The changes increased during sanctions and decreased afterwards. The fall of Baghdad in 2003, followed by rapid economic boom, marked the greatest cause in land use change, especially in changes-susceptible cultivated areas. Conclusions: Shrinkage of forest patches in the lower part of the park increases the distance between them, which contributes to a decline in biological diversity from decreasing habitat area. Lastly, the results confirm the applicability of the combined method of remote sensing and landscape metrics.

Analyzing the effects of urban expansion on land surface temperature patterns by landscape metrics: a case study of Isfahan city, Iran.

Urban expansion can cause extensive changes in land use and land cover (LULC), leading to changes in temperature conditions. Land surface temperature (LST) is one of the key parameters that should be considered in the study of urban temperature conditions. The purpose of this study was, therefore, to investigate the effects of changes in LULC due to the expansion of the city of Isfahan on LST using landscape metrics. To this aim, two Landsat 5 and Landsat 8 images, which had been acquired, respectively, on August 2, 1985, and July 4, 2015, were used. The support vector machine method was then used to classify the images. The results showed that Isfahan city had been encountered with an increase of impervious surfaces; in fact, this class covered 15% of the total area in 1985, while this value had been increased to 30% in 2015. Then LST zoning maps were created, indicating that the bare land and impervious surfaces categories were dominant in high temperature zones, while in the zones where water was present or NDVI was high, LST was low. Then, the landscape metrics in each of the LST zones were analyzed in relation to the LULC changes, showing that LULC changes due to urban expansion changed such landscape properties as the percentage of landscape, patch density, large patch index, and aggregation index. This information could be beneficial for urban planners to monitor and manage changes in the LULC patterns.

Fourteen years of anthropization dynamics in the Uapaca bojeri Baill. forest of Madagascar

Anthropization of forest landscapes is a major threat to ecosystems and biodiversity. To gather comprehensive information on anthropization dynamics in forest landscapes, fine-scale surveys of deforestation are required, coupled with detailed analysis of both spatial transformation processes and forest patch geometry. We conducted such a comprehensive study in a monospecific Uapaca bojeri (Baill.) forest of Madagascar, between 1999 and 2013. A diachronic set of four maps was produced and deforestation rates were calculated. Spatial transformation processes were described using Bogaert et al. (2004) typology. Forest patch geometry was monitored using largest patch index, mean patch size, and squared mean patch size to describe patch size dynamics, mean shape index and area weighted mean shape index to describe patch compactness, and fractal dimension analysis to describe patch outline complexity. For fractal dimension analysis, an innovative segmented regression model (Muggeo 2008) was used to separately quantify fractal dimensions for multiple ranges of patch sizes. Our results showed a growing anthropization of the U. bojeri forest landscape in the area, through a strong yet decelerating deforestation (from − 59.5% year−1 between 1999 and 2005 to − 2.84% year−1 between 2009 and 2013), clear forest fragmentation, and a subtle yet growing-in-scale simplification of patch geometry for small forest patches. Deforestation was artisanal in nature and, in 2013, large patches were withdrawing to less accessible topographic features. Our results forecast a medium-term loss of resilience of the U. bojeri forest in the area, if no direct forest conservation measures are taken.

Multi-scale analysis of the relationship between landscape patterns and a water quality index (WQI) based on a stepwise linear regression (SLR) and geographically weighted regression (GWR) in the Ebinur Lake oasis.

Water quality is highly dependent on landscape characteristics. This study explored the relationships between landscape patterns and water quality in the Ebinur Lake oasis in China. The water quality index (WQI) has been used to identify threats to water quality and contribute to better water resource management. This study established the WQI and analyzed the influence of landscapes on the WQI based on a stepwise linear regression (SLR) model and geographically weighted regression (GWR) models. The results showed that the WQI was between 56.61 and 2886.51. The map of the WQI showed poor water quality. Both positive and negative relationships between certain land use and land cover (LULC) types and the WQI were observed for different buffers. This relationship is most significant for the 400-m buffer. There is a significant relationship between the water quality index and landscape index (i.e., PLAND, DIVISION, aggregation index (AI), COHESION, landscape shape index (LSI), and largest patch index (LPI)), demonstrated by using stepwise multiple linear regressions under the 400-m scale, which resulted in an adjusted R 2 between 0.63 and 0.88. The local R 2 between the LPI and LSI for forest grasslands and the WQI are high in the Akeqisu River and the Kuitun rivers and low in the Bortala River, with an R 2 ranging from 0.57 to 1.86. The local R 2 between the LSI for croplands and the WQI is 0.44. The local R 2 values between the LPI for saline lands and the WQI are high in the Jing River and low in the Bo River, Akeqisu River, and Kuitun rivers, ranging from 0.57 to 1.86.

Impact of an agri-environmental scheme on landscape patterns

Human culture and policy play an important role in structuring landscape patterns. Agriculture is an example of a land use practice that has altered landscape patterns worldwide and agricultural intensification coupled with broad patterns in land use change have resulted in decreased cover of native plant communities and a loss in biodiversity. The Conservation Reserve Program (CRP) was initially developed to address large agricultural surpluses by transitioning highly erodible cropland into conservation-related perennial cover types. Research has demonstrated that this program can help restore ecological processes across landscapes. However, this program can also impact landscape patterns across multiple spatial scales, though its direct influence to these patterns is poorly understood. To understand the contribution of currently enrolled CRP lands to broadscale landscape patterns, we used FRAGSTATS and non-metric multidimensional scaling (NMDS) to assess how patch- and class- scale landscape patterns change in relation to grasslands across the state of Oklahoma with the presence and theoretical absence of CRP. Furthermore, we determined how these patterns vary across three spatial extents: the statewide, the Environmental Protection Agency (EPA) defined ecoregions, and the county extents within Oklahoma. Though impacts at the statewide extent were minimal, NMDS results indicated shifts in landscape patterns across ecoregions and counties that were primarily associated with increases in effective mesh size and largest patch index. Our results indicate that CRP can help maintain complexity of the grassland matrix through improving connectivity. However, the direct impacts of CRP on landscape patterns is dynamic across spatial scales and these effects influence the overall perceived impact of CRP to grassland patterns.

URBAN LANDSCAPE SPATIAL PATTERN ESTIMATION OF CITIES IN SHANDONG PROVINCE USING NIGHTTIME LUMINOSITY DATA

Abstract. China’s cities have been undergoing rapid and intense urbanization processes in the past few decades. Shandong is a coastal province which is located in East China with big economy and population scales, and which also plays an important role in the rapid process of China’s modernization. The DMSP/OLS dataset has been widely used for the urban development assessments in long time-series and large spatial scales situations. In this paper, we used a time series of nighttime light data to estimate the landscape spatial pattern changes of cities in Shandong province from 1994 to 2012. Nine landscape metrics were calculated and analyzed to figure out the spatial patterns of urban area developments of the cities in Shandong province. The landscape metrics include the number of patches (NP), the landscape total area (TA), the aggregation index (AI), the largest patch index (LPI), the mean patch area (AREA_MN), the landscape shape index (LSI), the total edge length (TE), the edge density (ED), and the mean radius of gyration (GYRATE_MN). The experimental results reveal that, in 1994–2012, the total urban area of cities in Shandong province expanded for 1.17 times, the average urban area increased by about 93.00%, the average annual growth rate of the TE metric is 2.67 %, while the ED metric decreased about 1.44 % annually. Bigger cities in this area show relative slower urbanization development processes, such as Jinan and Qingdao. Coastal cities represented much more rapid expansion velocities than inland cities. In the middle area of Shandong province, the connectivity between developed urban areas was constantly increased.