Degree Of Landscape Fragmentation Research Articles

Analysis of the Spatial Pattern and Driving Forces of Linpan in Western Sichuan

Abstract. This study aims to explore the landscape pattern and its driving forces of Linpan in western Sichuan, aiming to gain a deeper understanding of the spatial distribution of this unique rural settlement form. The landscape indices and redundancy analysis method were employed to investigate the landscape pattern and driving forces of Linpan in the western Sichuan region. By extracting the spatial information of Linpan in the study area, quantitative analysis of their landscape pattern was conducted using landscape indices. The results reveal certain characteristics of the landscape pattern of Linpan in the study area, where Longquanyi exhibits the highest degree of landscape fragmentation, with the highest patch density and smaller average patch size, yet the highest landscape diversity, while Wenjiang shows the lowest diversity, and Xinjin exhibits a more dispersed distribution of patches, and Dujiangyan has the highest number of patches. Using redundancy analysis, this study reveals the influence of natural and social driving forces on the landscape pattern of Linpan in Western Sichuan. The results indicate that urbanization rate, patch density, mean patch size, and average elevation are significant factors influencing the distribution and morphology of Linpan. These factors affect the spatial layout and connectivity of Linpan, driving changes in the land use structure, and profoundly impacting the landscape pattern of Linpan. To achieve the ecological sustainability, it is essential to comprehensively consider the impacts of both natural and human factors, scientifically plan and manage Linpan, and promote their harmonious coexistence with the surrounding environment.

Soil organic carbon sequestration can be promoted through the improvement of landscape configuration heterogeneity in typical agricultural regions of northeast China

Landscape heterogeneity is considered a promising option for building resilient and sustainable agroecosystems. Understanding the relationships between farmland soil organic carbon (SOC) and landscape heterogeneity can support soil carbon sequestration and better serve food security and climate change. However, the influence extent and optimal scale of farmland landscape heterogeneity (i.e. landscape composition and landscape configuration heterogeneity) on SOC remains unclear. In this study, we established the relationships between multi-scale landscape heterogeneity and SOC in a typical grain-production county of northeast China. Stepwise regression results showed that when the buffer radius was 2000 m, the interpretation of SOC by landscape heterogeneity was the largest. The effects of landscape composition and landscape configuration on SOC were further decomposed by Variance Partitioning Analysis, and we found that independent interpretation ability of landscape configuration (8%) exceeded landscape composition (7%). The result of soil mapping combined with landscape indexes also showed that landscape configuration contributed more to the increased accuracy. Moreover, we found that correlation between configuration indexes and SOC at the class level was less related than that at the landscape level, among which the two most important indexes were Mean Fractal Dimension Index (FRAC_MN) and Number of Patches (NP). FRAC_MN was even more important than natural factors, indicating the validity of landscape as an indicator of human activities should not be ignored when considering farmland SOC. Overall, the results of this study revealed that the negative effects of agricultural intensification on SOC can be buffered to a certain extent by increasing the complexity of patch shape and reducing the degree of landscape fragmentation at the landscape level, providing hope for the sustainable development in intensive agricultural areas. In addition, due to the scale effect of landscape heterogeneity on farmland SOC, we suggest that decision makers should consider the spatial scale in landscape allocation and planning. This study provides a scientific reference for realizing the balance between grain production and ecological function in intensive agricultural areas.

Segment Anything Model Combined with Multi-Scale Segmentation for Extracting Complex Cultivated Land Parcels in High-Resolution Remote Sensing Images

Accurate cultivated land parcel data are an essential analytical unit for further agricultural monitoring, yield estimation, and precision agriculture management. However, the high degree of landscape fragmentation and the irregular shapes of cultivated land parcels, influenced by topography and human activities, limit the effectiveness of parcel extraction. The visual semantic segmentation model based on the Segment Anything Model (SAM) provides opportunities for extracting multi-form cultivated land parcels from high-resolution images; however, the performance of the SAM in extracting cultivated land parcels requires further exploration. To address the difficulty in obtaining parcel extraction that closely matches the true boundaries of complex large-area cultivated land parcels, this study used segmentation patches with cultivated land boundary information obtained from SAM unsupervised segmentation as constraints, which were then incorporated into the subsequent multi-scale segmentation. A combined method of SAM unsupervised segmentation and multi-scale segmentation was proposed, and it was evaluated in different cultivated land scenarios. In plain areas, the precision, recall, and IoU for cultivated land parcel extraction improved by 6.57%, 10.28%, and 9.82%, respectively, compared to basic SAM extraction, confirming the effectiveness of the proposed method. In comparison to basic SAM unsupervised segmentation and point-prompt SAM conditional segmentation, the SAM unsupervised segmentation combined with multi-scale segmentation achieved considerable improvements in extracting complex cultivated land parcels. This study confirms that, under zero-shot and unsupervised conditions, the SAM unsupervised segmentation combined with the multi-scale segmentation method demonstrates strong cross-region and cross-data source transferability and effectiveness for extracting complex cultivated land parcels across large areas.

Assessment of coastal landscape fragmentation and its driving factors based on optimal scale: A case study of the Yellow River Delta, China

Since the large-scale oil exploration and development in the 1960 s, the Yellow River Delta (YRD) has undergone rapid industrialization and urbanization. Concurrently, the regional landscape ecological structure has experienced significant changes, and the degree of landscape fragmentation has increased. Therefore, a comprehensive assessment of the spatiotemporal dynamics and formation mechanisms of landscape fragmentation is crucial for the protection and restoration of natural ecosystem in the YRD. This study constructs an evaluation index system for landscape fragmentation in the YRD from three perspectives: quantitative characteristics, shape features, and spatial distribution. By combining inflection point analysis, landscape area loss index, and geostatistical models, the optimal spatial scale of landscape fragmentation from 2000 to 2020 is determined. Additionally, the study analyzes the spatiotemporal changes in landscape fragmentation and employs the optimal parameters-based geographical detector (OPGD) model to reveal the formation mechanisms of spatial heterogeneity in landscape fragmentation. The study findings are as follows: (1) The optimal spatial resolution for analyzing landscape fragmentation in the YRD was 80 m, and the extent was 880 m. (2) Between 2000 and 2020, landscape fragmentation in the YRD increased, with the highest level recorded in 2020. Highly fragmented areas, particularly inland regions, expanded remarkably, whereas coastal areas experienced lower fragmentation levels. (3) Distance to rivers and ditch density were the primary factors affecting landscape fragmentation, followed by land-use type and average land gross domestic product. The influence of natural factors was relatively minimal. The interaction between factors had a greater influence on landscape fragmentation compared to individual factors. The distance to rivers and land-use type exhibited the most substantial enhancement effects following interaction with other factors. This study provides valuable insights into the spatiotemporal dynamics and mechanisms of landscape fragmentation in the YRD, providing valuable guidance for the sustainable management and ecological restoration of the region and other similar ecologically sensitive areas.

Modelling Multi-Scenario Ecological Network Patterns and Dynamic Spatial Conservation Priorities in Mining Areas

Mining activities have significantly altered the land use patterns of mining areas, exacerbated the degree of landscape fragmentation, and thereby led to the loss of biodiversity. Ecological networks have been recognized as an essential component for enhancing habitat connectivity and protecting biodiversity. However, existing studies lack dynamic analysis at the landscape scale under multiple future scenarios for mining areas, which is adverse to the identification of ecological conservation regions. This study used the MOP-PLUS (multi-objective optimization problem and patch-level land use simulation) model to simulate the land use patterns in the balance of ecology and economy (EEB) scenario and ecological development priority (EDP) scenario for the Shendong coal base. Then, climate change and land use patterns were integrated into ecosystem models to analyze the dynamic changes in the ecological networks. Finally, the conservation priorities were constructed, and dynamic conservation hotspots were identified using landscape mapping methods. The following results were obtained: (1) From 2000 to 2020, large grassland areas were replaced by mining areas, while cultivated land was replenished. By 2030, the forest and grassland areas (967.00 km2, 8989.70 km2) will reach their peaks and the coal mine area (356.15 km2) will reach its nadir in the EDP scenario. (2) The fragmentation of ecological sources intensified (MPS decreased from 19.81 km2 to 18.68 km2) and ecological connectivity declined (in particular, α decreased by 6.58%) from 2000 to 2020. In 2030, the connectivity in the EDP scenario will increase, while the connectivity in the EEB scenario will be close to that of 2020. (3) The central and southeastern parts of the Shendong coal base have higher conservation priorities, which urgently need to be strengthened. This study offers guidance on addressing the challenges of habitat and biodiversity conservation in mining areas.

Influence of landscape pattern changes on water conservation capacity: A case study in an arid/semiarid region of China

With the accelerating changes of land use/cover caused by natural and human factors, landscape pattern has undergone significant changes. Given the scarcity of water resources and the degradation of ecological functions in arid and semi-arid regions of China, it is necessary to analyze the impact of landscape pattern changes on water conservation. Taking the Wei River Basin (WRB) as the research area, based on water balance equations, FRAGSTATS 4.2 software, and correlation analysis method, this study explored the spatiotemporal distribution characteristics of water conservation and landscape pattern in the WRB from 1990 to 2020, as well as the correlations between the two. The results showed that from 1990 to 2020: (1) the water conservation capacity (WCC) showed no insignificant change trend (P > 0.05) in sub water basins as well as the entire WRB, and it presented a spatial distribution pattern of more in the south and west, and less in the north and east; (2) the landscape diversity and fragmentation of the WRB have increased, and the patch shapes tended to be complex, while connectivity and agglomeration between patches decreased; (3) The WCC had significant negative correlations with the Contagion Index (CONTAG), connectivity index (COHESION), and largest patch index (LPI), while had significant positive correlations with landscape shape index (LSI), Shannon diversity index (SHDI), and separation index (SPLIT), indicating that the increase of landscape fragmentation and diversity was conducive to the improvement of WCC. In the process of ecological landscape planning and optimization, the fragmentation degree of landscape can be appropriately increased. (4) Vegetated grassland, forestland, and farmland were the main sources of WCC, with average WCC values of 81.90, 68.04, and 8.72 mm, respectively. NDVI of the watershed increased significantly (P < 0.01) during the research period and showed a significant positive correlation with WCC, indicating the promoting effect of increasing vegetation coverage on WCC. Relevant results may provide referential information for ecological restoration and optimization of landscape pattern in arid/semiarid regions.

Research on the Protection and Dissemination of Cultural Heritage in Rural Landscapes Based on Image Processing

Abstract The countryside is an important part of the social development process, but with the acceleration of urbanization, the protection of rural landscapes as cultural heritage is facing an increasingly severe situation. In this study, image radiation correction, image fusion, cropping and mosaicing, geometric correction, band selection, and image enhancement are applied to rural landscapes using remote sensing image processing technology. A digital protection system for rural landscape cultural heritage is created using the processed rural landscapes. By comparing the accuracy of this paper’s method to other classification methods, we can explore the classification performance of this paper’s PCA method. By comparing the changes in rural landscape types before and after landscape protection, the effect of landscape protection is explored. Finally, the communication effect of rural landscapes on social media is explored by utilizing the evaluation index system. The PCA method employed in this paper achieves a landscape classification accuracy of 83%, which is significantly superior to the IHS transformation method (73.5%) and the Brovey transformation method (76%). After the rural landscape protection, the degree of landscape fragmentation in Village A was significantly improved compared to before the protection, and the effect of protection was remarkable. The scores of social media users on each dimension of the rural landscape communication effect in Village A were greater than 4, and rural landscape communication achieved a positive effect.

Landscape Fragmentation and Spatial Autocorrelation of a Typical Watershed in the Wenchuan Earthquake-Affected Area—A Case Study in the Longxi River Basin

The 2008 8.0 Ms Wenchuan earthquake caused serious ecological degradation in the northwest of China’s Sichuan Province. Elucidating landscape fragmentation and spatial pattern of post-earthquake landscape is of great interest in order to improve ecological restoration and predict the spatial distribution of damaged ecosystems in earthquake-affected areas. We used four real-time remote sensing images to analyze the landscape pattern characteristics and spatial autocorrelation of the Longxi River Basin before and after the Wenchuan earthquake during the period from 2005 to 2015. In the study period, the degree of landscape fragmentation increased 1 year after the earthquake in 2009 but decreased in 2011 and 2015. The spatial distribution of forest, farmland, and shrub-grassland had significantly positive spatial correlation and the characteristics of spatial aggregation from 2005 to 2015. Construction land had no significant spatial correlation before the earthquake in 2005, but significantly positive spatial correlation after the earthquake, while traffic land had no significant spatial correlation across the study period. Unlike the other landscape types, geological disasters changed from a significantly negative spatial correlation before the earthquake to a significantly positive spatial correlation after the earthquake. However, the positive autocorrelation of all landscape types decreased with the increase of space distance, but in different distance-decay rates. The High-high spatial aggregation areas of geological disasters and construction land clustered gradually upstream of the basin and distributed in Longchi town, respectively; those of farmland distributed in the southeast of the basin increased in 2009 but then decreased, while those of forests had the opposite pattern as the dominant landscape type after the earthquake. Our results elucidated the spatial structure and distribution features of the Longxi River Basin to give a theoretical foundation for assessing the effects of ecological restoration and reconstruction management in earthquake-affected areas.

Features of architectural landscape fragmentation in traditional villages in Western Hunan, China

With rapid industrialization and urbanization in China, inadequate preservation of traditional architecture coupled with natural deterioration have led to the fragmentation of architectural landscapes. Drawing from ecological fragmentation research in landscape ecology, we consider the cultural landscape as our research object, viewing buildings as landscape patches, and determine a system for measuring architectural landscape fragmentation in traditional villages. The study shows the degree of landscape fragmentation can reveal the characteristics of traditional villages and the process of regional modernization. The results are as follows: (1) From the perspective of landscape diversity, the study area was rich in landscape types in all dimensions, and the relative evenness index was high, signifying evident or severe fragmentation. (2) The index of landscape heterogeneity in the dimensions of building quality, height, and landscape appearance is low in the study area, with mild levels of landscape fragmentation caused by heterogeneity in the aforementioned dimensions. (3) Mild fragmentation suggests the integrity and homogeneity of architectural landscape types, reflecting a lagging level of economic development, whereas high fragmentation signifies rapid economic development, leading to a substantial deterioration in the integrity and homogeneity of architectural landscape types. Therefore, efforts to preserve and develop traditional villages should not solely aim for low fragmentation as it could potentially constrain sustainable development.

Evolution Characteristics of Landscape Patterns and the Response of Surface Runoff in a Rapid Urbanization Area: Focus on the Chang–Zhu–Tan Metropolitan Area of China

With the acceleration of urbanization, the disturbance to urban landscape patterns causes changes to urban surface runoff and increases the risk of urban waterlogging. We studied the response relationship between landscape pattern change and surface runoff in the Chang–Zhu–Tan metropolitan area for the period from 2000 to 2020, analyzing the driving factors that affected surface runoff. The influence of landscape pattern evolution on surface runoff was studied using the SCS-CN flow generation model, the moving window method, and Pearson’s analysis. The analysis showed that between 2000 and 2020, the forest area decreased, while the impermeable land area increased substantially. At the same time, the landscape spread degree (CONTAG) decreased, whereas the landscape fragmentation degree (DIVISION) increased, and the Shannon diversity index (SHDI) and landscape shape index (LSI) increased. The surface runoff in the main urban areas of Chang–Zhu–Tan increased substantially. The results showed that surface runoff is negatively correlated with SHDI, LSI, and DIVISION but displays a positive relationship to CONTAG. Soil texture and precipitation had the greatest impact on surface runoff. This study emphasizes the importance of landscape pattern evolution to surface runoff in rapidly developing metropolitan areas in terms of reducing surface runoff, alleviating urban waterlogging and preventing regional floods. Our research additionally seeks to optimize the landscape pattern of the Chang–Zhu–Tan metropolitan area.

Are There Any Land Use Dynamics in the Upper Bistrița Basin, Eastern Carpathians, Romania, in the Period 1990–2021?

This paper aims to assess land use and land use change (LULC). For this purpose, supervised mapping on satellite imagery, using the European Space Agency (ESA) SNAP programme from LANDSAT databases, publicly accessible through the European Copernicus portal, was used. At the same time, an analysis of the degree of landscape fragmentation in the study area was carried out, which revealed that, because of the particular fragmentation of small polygons, the best results were obtained via analysis/supervised mapping on satellite images. This method, once validated in the field, reflects the most accurate land use pattern in the analysed area, with wide applications in studies of agriculture, biodiversity, geography, etc. Between 2000 and 2010, significant changes were registered. Artificial surfaces decreased by approximately 400 ha, showing a negative trend in the last period of the interval. Coniferous forests reached their maximum threshold in 2000 (with 114,400 ha) in conjunction with the “Grassland” class, which exceeded 16,700 ha. In 2010, a drastic decrease in “Grassland” was recorded, reaching half of the values of 1990 and 2000, now having only 15,684 ha. Land cover changes were significant when comparing the period before 1989 with 2021. This fact was due to socio-economic changes in society, in large part caused by changes in professions and the way of life of the population.

Analysis of the relationship between landscape fragmentation and ecosystem service value in northern Shaanxi, China.

Landscape fragmentation affected the structure and function of the ecosystem, resulting in an impact on ecosystem service value (ESV). This paper analyzed the correlation between landscape fragmentation and ESV using land-use data from northern Shaanxi covering three periods from 2000 to 2020. The paper employed the granularity deduction method, spatial autocorrelation analysis, and value equivalent method to study the fragmentation characteristics of the regional landscape and the spatial-temporal evolution of ESV. The research findings indicated that the optimal granularity was 150 m, and the amplitude was 5 km × 5 km. The study found that the degree of landscape fragmentation was positively correlated with patch density (PD), division index (DIVISION), and Shannon's diversity index (SHDI), while negatively correlated with the largest patch index (LPI), patch cohesion index (COHESION), and effective mesh size (MESH). Moreover, the total ESV in the study area showed a decreasing trend, with grass, forest, and cultivated land being the three land-use types that contributed the most value. The analysis indicated that there was a negative correlation between the degree of landscape fragmentation and ESV. As the degree of landscape fragmentation increased, ESV decreased. The correlation between landscape fragmentation and ESV discussed in this paper provided valuable insights into the optimal utilization and sustainable development of regional land resources.

Projection of landscape ecological risk and exploration of terrain effects in the Qilian Mountains, China

AbstractThe development of a reasonable landscape ecological risk (LER) assessment system is the key means to establish an eco‐safety early warning mechanism, promote ecological protection, and achieve sustainable management of regional ecosystems. Based on the Cellular Automaton‐Markov (CA‐Markov) model, we predicted the land use/cover changes (LUCC) in 2026 and 2034 in the typical arid and semiarid mountainous area of the Qilian Mountains. We constructed an LER model to analyze the spatial–temporal changes in LER, quantified the driving mechanism, and synthesized the constraining effect of terrain features. The results showed that the study area was dominated by ecologically stable areas in 1980–2000 and 2010–2018. Ecologically improved and deteriorated areas in the central and northwest expanded in 2000–2010 and 2018–2036, which was attributed to ecological restoration policies (returning farmland to forest and grassland, closing mountains to forest and grassland, etc.) and economic development (livestock and mineral development, etc.). Due to the frequent interference of human activities in flat and complex terrain areas, the degree of landscape fragmentation, separation, and vulnerability is enhanced, and the ecological conditions of bare land and snow cover are relatively fragile, resulting in high ecological risk. Therefore, we could focus on zoning management and rational land use planning. This study provides a new framework for controlling LER in the Qilian Mountains, and will provide a scientific reference for the formulation of risk mitigation strategies in other arid and semiarid mountains worldwide.

The Changes in Dominant Driving Factors in the Evolution Process of Wetland in the Yellow River Delta during 2015–2022

Most of the previous studies exploring the changing patterns of wetland in the Yellow River Delta (YRD) were conducted based on sparse time-series images, which ignored its severe environmental gradient and rapid evolution process of the wetland. The changes in the dominant factors in the evolution of the wetland in the YRD are not clear. This study used the dense time-series Sentinel-2 images to establish a wetland database of the YRD, and then analyzed the spatial distribution characteristics of, and temporal changes in, the wetland during 2015–2022. Finally, the dominant factors of the spatio-temporal evolutions of the wetland were explored and revealed. The results showed the following. (1) During 2015–2022, the wetland in the YRD was dominated by artificial wetland, accounting for 54.02% of the total wetland area in the study area. In 2015–2022, the total wetland area increased by 309.90 km2, including an increase of 222.63 km2 in natural wetlands and 87.27 km2 in artificial wetlands. In the conversion between wetland types, 218.73 km2 of artificial wetlands were converted into natural wetlands, and 75.18 km2 of natural wetlands were converted into artificial wetlands. The patch density of rivers, swamps, and salt pans increased, showing a trend of fragmentation. However, the overall degree of landscape fragmentation in wetlands weakened. The trend of changes in the number of patches and landscape shape index was the same, while the trend of changes in Shannon’s diversity index and Contagion index was completely opposite. (2) Natural factors, such as precipitation (0.51, 2015; 0.65, 2016), DEM (0.57, 2017; 0.47, 2018; 0.49, 2020; 0.46, 2021), vegetation coverage (0.59, 2019), and temperature (0.48, 2022), were the dominant influencing factors of wetland changes in the YRD. The dominant single factor causing the changes in artificial wetlands was vegetation coverage, while socio-economic factors had lower explanatory power, with the average q value of 0.18. (3) During 2015–2022, the interactions between the natural and artificial factors of the wetland changes were mostly nonlinear and showed double-factor enhancement. The interactions between temperature and sunshine hours had the largest explanatory power for natural wetland change, while interactions between precipitation and vegetation coverage, and between temperature and vegetation coverage, had large contribution rates for artificial wetland change. The interactions among natural factors had the greatest impacts on wetland change, followed by interactions between natural factors and socio-economic factors, while interactions among socio-economic factors had more slight impacts on wetland change. The results can provide a scientific basis for regional wetland protection and management.

Habitat selection of wintering cranes in typical wetlands in the middle and lower reaches of the Yangtze River over the past 20 years, China

The wetlands in the middle and lower reaches of the Yangtze River are the main overwintering and perching places for cranes. To examine the habitat selection mechanism of cranes in this area, two natural wetland reserves, Shengjin Lake and Poyang Lake, which are the main habitats of typical cranes, were selected as the study area. Using 20years of Landsat satellite image data (between 1999 and 2019), the vegetation cover index was calculated from a pixel dichotomy model, and the landscape pattern index was obtained through Fragstats. The entropy method was adopted to determine the weight of the landscape index, and then, the habitat suitability index was calculated. Combined with the number of typical crane populations in the reserve, the selection mechanism of overwintering habitat of cranes was revealed. On the change of land-use type, the crane habitat of Shengjin Lake transferred more to non-crane habitat, and other land types increased, resulting in the decrease of crane habitat area. However, the change of crane habitat in Poyang Lake Reserve was small, so it can accommodate more cranes to overwintering here. In terms of vegetation coverage, most of the vegetation cover areas of Shengjin Lake were woodland near or far from the lake, but the woodland was not the habitat of cranes. Most of the vegetation-covered areas of Poyang Lake are grassland near the lake, which provide rest and foraging places for cranes. In the landscape pattern, the number of landscape patches in Shengjin Lake was large, the degree of landscape fragmentation was higher than that in Poyang Lake, the landscape complexity was higher, and the landscape diversity was simpler. This is not conducive to the maintenance of crane habitat, but also reduces the attractiveness of overwintering cranes, while the landscape suitability of crane habitat in Poyang Lake was higher than that in Shengjin Lake, and cranes were more likely to choose Poyang Lake as their overwintering habitat.

Analysis of the impact of traditional ethnic villages in Hani area on sustainable development.

Rapid economic development and accelerated urbanization have seriously affected the development of traditional ethnic villages in China. We used the minimum cumulative resistance (MCR) model based on land use, landscape pattern, and ecosystem service value (ESV) to evaluate the spatio-temporal dynamics of sustainable development in Hani traditional ethnic villages from 1995 to 2020. By analyzing changes in sustainability indicators in the Hani area and different buffer zones, this paper aims to assess the impact of ethnic villages in the Hani Area on sustainable development and provide recommendations for the sustainable development of traditional ethnic Hani villages. The results indicated that: (1) The area of construction land and landscape fragmentation in the Hani area significantly increased and the value of ecosystem services and levels of sustainable development decreased each year during the study period; (2) The area of cropland in the 2 km buffer zone of the traditional ethnic villages increased, the degree of landscape fragmentation, the value of ecosystem services, and the level of sustainable development were lower than in the 4 km buffer zone during the study period. This is due to population increases in traditional ethnic Hani villages, as well as the intensive reclamation of cropland, increased construction land, and landscape fragmentation. We suggest that the Hani should implement scientific land planning and management policies to protect the local ecosystem and realize the sustainable development of traditional ethnic Hani villages.

Spatio-Temporal Changes in Land Use and Habitat Quality of Hobq Desert along the Yellow River Section.

As a key area in the Yellow River basin for sand control and management, the land change process in the Hobq Desert plays a crucial role in keeping the river and desert ecosystems and promoting the construction of ecological civilization in human systems. Based on multi-temporal remote sensing from 1991 to 2019 in the Hobq Desert along the Yellow River section, this study selected spatial statistical methods (land-use monitoring and landscape metrics) to examine land-use change dynamics. Then, we evaluated habitat quality using the InVEST model and quantitatively analyzed the factors causing spatial changes in habitat quality using geographic detectors. Finally, this paper predicted the pattern of land use and habitat quality in 2030 using the PLUS model. The results reveal that (1) from 1991 to 2019, the total area of forest grassland increased by 3572.5 km2, providing the most vegetation cover, and the sandy land and water area decreased continuously, while the cultivated land and construction land increased. There were 38.01% conversions of land types, with the land-use dynamic decreasing the greatest in sandy land (-12.66%) and increasing the greatest in construction land (9.26%); the comprehensive land-use dynamics were the highest in 2010-2019 (1.68%), which was the most active stage during our study period. (2) Both of the landscape indices NP and PD showed "N" type fluctuations during 1991-2019, and CONTAG and LSI rose from 69.19% to 70.29% and 36.01% to 38.89%, respectively, indicating that the land-use degree of landscape fragmentation increased, landscape connectivity turned better, and landscape dominance was enhanced, balanced, and developed evenly in overall landscape type. (3) From the overall region analysis, the average habitat quality in 1991, 2000, 2010, and 2019 was 0.3565, 0.5108, 0.5879, and 0.6482, respectively, with the overall habitat value showing a gradually increasing trend. Spatially, the habitat quality along the Yellow River section of the Hobq Desert has a certain regularity, and the overall pattern there is high in the south and low in the north, high in the east and west, and low in the middle. (4) The change in land use between 2019 and 2030 is similar to the previous period, but the change rate is generally lower. The habitat quality improved significantly, with the growth of high and medium habitat quality.

Simulation, prediction and driving factor analysis of ecological risk in Savan District, Laos

Introduction: In recent years, Laos, with its unique geographical advantages, has vigorously developed overseas trade and cultural tourism industry, which has promoted local economic development and introduced numerous ecological and environmental problems.Method: Therefore, this research took Savan District as the research area, built the landscape ecological risk assessment model to reveal the spatiotemporal evolution characteristics of Savan District’s ecological risk from 2000 to 2020. Then, the Geodetector model was utilized to explain the driving forces behind changes in the landscape’s ecological risk. Finally, the Markov-PLUS coupling model was used to simulate and predict the changes in the land use pattern and ecological risk in the Savan District in 2030.Results: The following results are presented. 1) The landscape types in Savan District are mainly cultivated land and forest land, with the lowest degree of landscape fragmentation and loss, and the highest degree of landscape loss in unused land. 2) From 2000 to 2020, the average ecological risk index of the whole study area was low and showed a decreasing trend yearly, with the area of low-risk areas accounting for more than 90%. 3) In 2030, the average ecological risk index of the entire Savan District and the two provinces will rise, meanwhile the low-risk areas in the midwest regions and high-risk areas in the northwest will increase.Discussion: This study can guide the future coordinated development of the social economy and ecological environment in Savan District, Laos, and has good reference significance for ecological construction in similar areas in Southeast Asia.

Evaluation and Prediction of Landscape Ecological Security Based on a CA-Markov Model in Overlapped Area of Crop and Coal Production

Overlapped areas of crop and coal production are responsible for national food security and mineral resource supply. However, long-term coal mining and urban and rural construction have continuously impacted the structure and functions of the original agricultural landscape ecosystem in the area and brought serious ecological security problems. On the basis of the results of remote sensing image classification of the Zhaogu mining area, this study explores the spatio-temporal variation characteristics of the landscape pattern and the evolution of ecological security and predicts the landscape ecological security status in 2029. Research results show that the evolution of the landscape pattern in the study area manifests obvious stage characteristics: from 2004 to 2014, the landscape pattern developed in the direction of fragmentation, irregularity, heterogeneity, and low connectivity; after 2014, the landscape pattern showed continuity, regularization, and high connectivity trends. By comparing the landscape ecological security of the study area from 2004 to 2019, a temporal change characteristic of first deteriorating and then gradually improving can be observed. By analyzing the changes in the distribution of the security status in the study area on a spatial scale, it can be found that the proportion of unsafe areas is significantly reduced in 2019 due to the influence of land remediation and reclamation. By constructing a CA-Markov prediction model with both spatial and quantitative advantages, the prediction results show that the degree of landscape fragmentation in the study area will be reduced, and the connectivity will be enhanced between 2019 and 2029. The shape of landscape patches tends to be regular, and the landscape heterogeneity will be enhanced. Overall, the landscape ecological security situation will continue to improve. The results could provide reference for ecological protection and related land reclamation planning of the mine area.

基于不同样带的干旱区城市景观格局时空演变特征——以张掖市为例

PDF HTML阅读 XML下载 导出引用 引用提醒 基于不同样带的干旱区城市景观格局时空演变特征——以张掖市为例 DOI: 10.5846/stxb202202210408 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（42101276）；甘肃省科技计划项目（20JR5RA529）；国家自然科学基金项目（41661035） Spatio-temporal evolution of urban landscape pattern in arid areas based on different zones: A case study of Zhangye City Author: Affiliation: Fund Project: National Natural Science Foundation of China, No.42101276; Science and Technology Project of Gansu Province, No.20JR5RA529; National Natural Science Foundation of China, No.41661035; Regional Fund of National Natural Science Foundation of China, No.41961027 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:景观格局的变化影响着区域生态安全及可持续发展，研究干旱区城市景观格局时空变化特征，对干旱区景观格局优化具有一定的指导意义。基于1987、1995、2000、2006、2011和2016年6期土地利用数据，利用景观格局指数计算方法，研究张掖市景观格局的时空演变特征。结果表明：（1）2016年张掖市景观类型主要为未利用地，最大斑块指数和斑块聚集度最高，草地和耕地次之，草地的斑块个数和密度最大。（2）张掖市景观格局呈现明显的地域分异特征，圈层梯度带上揭示了绿洲-荒漠用地变化，研究期内第1梯度带内破碎度先上升后下降，城市在2006-2016年扩张较快，其余梯度带破碎度逐年升高；空间演变上，居住地在圈层上的变化呈"L"型，未利用地呈"N"型，张掖市从中心城区到外围区域依次为绿洲城市区、绿洲农业区和自然景观区。（3）水平样带揭示了山地-绿洲-荒漠的用地变化，将张掖市分为4类区域，分别为绿洲城市区、绿洲农业区、荒漠区、山地区；西北-东南样带上景观破碎度年变化不规律，在空间上经过居民点波动变化；东北-西南样带研究期内景观水平指数经过居民点波动变化，其余范围内年变化较稳定，中心城区景观异质性较强。（4）人类围绕河流进行各种生产生活活动，将河流样带分为上中下三段，样带上段和下段景观指数年变化基本保持稳定，以未利用地为主，上段存在部分林地、草地；中段景观指数在空间上波动变化，景观类型以未利用地和耕地为主。 Abstract:The change of landscape pattern affects the regional ecological security and sustainable development. The study on the spatio-temporal change characteristics of urban landscape pattern has a certain guiding significance to the optimization of landscape pattern in arid areas. Based on the land use data of 1987, 1995, 2000, 2006, 2011 and 2016, the temporal and spatial evolution characteristics of landscape pattern in Zhangye City were studied by using landscape pattern index calculation method. The results showed that:(1) The unused land was the main landscape type in Zhangye City in 2016, and the maximum patch index and patch aggregation degree were the highest, followed by grassland and cultivated land, and the grassland patch number and density were the largest. (2) The landscape pattern of Zhangye City showed obviously regional differentiation characteristics, and the gradient zone of circle layer revealed the change of oasis-desert land. The fragmentation degree in the first gradient zone increased firstly and then decreased during the study period, and the Zhangye City expanded rapidly from 2006 to 2016, while the fragmentation degree in the rest gradient zones increased year by year. In terms of spatial evolution, the change of residential area on the circle layer is "L" shape, and the unused land is "N" shape. From the central area to the periphery area, Zhangye City was divided into oasis urban area, oasis agricultural area and natural landscape area successively. (3) The horizontal transect revealed the land use change of mountain, oasis and desert, and Zhangye City was divided into four regions:oasis urban area, oasis agricultural area, desert area and mountain area. The annual change of landscape fragmentation degree in northwest-southeast transect is irregular, and fluctuated through residential area in space. The landscape level index from the northeast to southwest transect fluctuated through residential areas during the study period, and the annual change was relatively stable in the remaining areas. The landscape heterogeneity of the central urban area was strong. (4) The river transect was divided into upper, middle and lower sections by human activities. The landscape index of the transect and the lower section remained stable, and the unused land was the main part, while the upper section had some woodland and grassland. The landscape index in the middle section fluctuated in space, and the landscape types were mainly unused land and cultivated land. 参考文献 相似文献 引证文献