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1
Sobhani, Ameneh, and Hassan Khosravi. "Assessing Environmental Sensitivity Areas to Desertification in North of Iran." Current World Environment 10, no. 3 (December 25, 2015): 890–902. http://dx.doi.org/10.12944/cwe.10.3.19.
Анотація:
The sensitivity map to desertification of Chehel-chai basin (North of Iran) has been elaborated by the crossing of fives criteria including climate, water erosion, soil, vegetation, and management, which have the main impact on the evolutionary process of desertification. The methodology is resulted from the desertification model of MEDALUS, which use qualitative index to define the land sensitive area to desertification. According to the factorial scaling technique, score-ranging from 1(good condition) to 2(deteriorated condition) is assigned to each indicator. Each index was assessed based on selected indicators, which resulted in qualitative mapping of each index based on geometric average of the indicators. Thematic databases, with a 1:50000 scale resolution, were integrated and elaborated in GIS software based on arc view3.2, Ilwis3.1 and ArcGIS9.3. The obtained results indicate that 39.39% of Chehel-chai basin is highly sensitive to desertification, 2.13 % has moderate sensitivity, only 2.43% has low sensitivity and 56.05% is non-sensitive. Studying the mean weight of numerical value, it is distinguished that the intensity of desertification for the total area is 1.32 which is classified as fragile (2).
2
Al-Yasiry, Ahmed F., Alaa M. Al-Lami, and Ali Al-Maliki. "Production of Environmental Sensitivity Maps for Desertification in Southern Marshes of Iraq." IOP Conference Series: Earth and Environmental Science 1215, no. 1 (July 1, 2023): 012023. http://dx.doi.org/10.1088/1755-1315/1215/1/012023.
Анотація:
Abstract The arid and semi-arid regions have faced critical desertification problems in the last decades. This phenomenon is caused either by human actions or natural circumstances. The study aims to identify the sensitive areas of desertification in the marshlands of southern Iraq using the Environmental Sensitivity Areas Index (ESAI) for desertification. The study area is located between longitudes (46.1° to 48.1° E) and latitude (29.55° to 32.55° N), which includes parts of the governorates of Al-Amarah, Al-Basara and Al-Nasiriyah in southern Iraq with an area of about 27,989 km2. Satellite image processing for the Landsat OLI sensor of 2021 was adopted to characterize the general appearance of the interest area. Arc Gis ver.10.7 programs were used to analyze different data and produce the Desertification Sensitivity Index (DSI) and maps for the parameters for evaluating southern marshes’ desertification. Nine parameters are grouped into three orderly indices concerning the behaviour of desertification, and weighting factors are assigned in each index. This study found that the study area highly sensitive to desertification represents (10781.14 km2 of the total area) about 38.52% of the study area. The area sensitive to desertification covers about 38.42%, about 10752.92 km2 of the total area. Areas of low sensitivity to desertification appear throughout the marshes, representing 23.06%, about 6454.67 km2 of the total area. The result shows that the area is suffering from reduced water supplies and the human destruction of natural grazing areas for urban expansion or cultivation of seasonal crops.
3
Ren, Yu, Xiangjun Liu, Bo Zhang, and Xidong Chen. "Sensitivity Assessment of Land Desertification in China Based on Multi-Source Remote Sensing." Remote Sensing 15, no. 10 (May 21, 2023): 2674. http://dx.doi.org/10.3390/rs15102674.
Анотація:
Desertification, a current serious global environmental problem, has caused ecosystems and the environment to degrade. The total area of desertified land is about 1.72 million km2 in China, which is extensively affected by desertification. Estimating land desertification risks is the top priority for the sustainable development of arid and semi-arid lands in China. In this study, the Mediterranean Desertification and Land Use (MEDALUS) model was used to assess the sensitivity of land desertification in China. Based on multi-source remote sensing data, this study integrated natural and human factors, calculated the land desertification sensitivity index by overlaying four indicators (soil quality, vegetation quality, climate quality, and management quality), and explored the driving forces of desertification using a principal component and correlation analysis. It was found that the spatial distribution of desertification sensitivity areas in China shows a distribution pattern of gradually decreasing from northwest to southeast, and the areas with very high and high desertification sensitivities were about 620,629 km2 and 2,384,410 km2, respectively, which accounts for about 31.84% of the total area of the country. The very high and high desertification sensitivity areas were mainly concentrated in the desert region of northwest China. The principal component and correlation analysis of the sub-indicators in the MEDALUS model indicated that erosion protection, drought resistance, and land use were the main drivers of desertification in China. Furthermore, the aridity index, soil pH, plant coverage, soil texture, precipitation, soil depth, and evapotranspiration were the secondary drivers of desertification in China. Moreover, the desertification sensitivity caused by drought resistance, erosion protection, and land use was higher in the North China Plain region and Guanzhong Basin. The results of the quantitative analysis of the driving forces of desertification based on mathematical statistical methods in this study provide a reference for a comprehensive strategy to combat desertification in China and offer new ideas for the assessment of desertification sensitivity at macroscopic scales.
4
Al- Janaby, Hojran, Abed Faiyyadh, and Mufid Al-Hadithi. "Assessing Environmental Sensitivity to Desertification in Heet-Haditha Region-Based on Method Multiple Criteria Decision Analyses." Iraqi Geological Journal 56, no. 1F (June 30, 2023): 51–63. http://dx.doi.org/10.46717/igj.56.1f.4ms-2023-6-12.
Анотація:
The study area suffers from significant climatic changes and high salinity, in addition to urban sprawl, which causes desertification. This study aims to analyze the indicators of desertification by means of multi-criteria decision analysis methods and to identify the most effected on the land's sensitivity to desertification. Nine main indicators have been used. The results show that the evaporation index, wind speed, relative humidity, and temperature are among the most sensitive indicators of the desertification phenomenon in the Heet- Haditha region, Iraq.
5
Prăvălie, Remus. "Cuantification Of Land Degradation Sensitivity Areas In Romania Using European DISMED Data." Present Environment and Sustainable Development 9, no. 2 (October 1, 2015): 73–86. http://dx.doi.org/10.1515/pesd-2015-0025.
Анотація:
AbstractLand degradation is presently an important environmental issue in many regions of the Globe, including Central South-Eastern Europe, where Romania is located. This study aims to quantify areas with significant sensitivity to degradation at national level, based on data provided by the European Environment Agency, obtained relatively recently through the DISMED project (Desertification Information System for the Mediterranean) in the Mediterranean and Central South-Eastern regions of Europe. The analysis is based on extracting SDI index (Desertification Sensitivity Index) information for the country’s entire territory, as well as for certain major regional, natural (landforms) and anthropogenic (counties) units. Thus, the areas corresponding to the most representative classes for land degradation potential in Romania were extracted, i.e. the ones with moderate and high sensitivity. The study also attempts to differentiate the degradation / desertification processes spatially, by delimiting drylands, for which the land degradation process is considered to be equivalent to desertification. The results showed that, at national level, there are ~ 72 000 km2 of lands with moderate and high degradation potential (30% of the country’s total surface), of which 80% (~ 57 000 km2) can be classified as sensitive to desertification. It was noticed that most degradation-prone areas are concentrated in the Romanian Plain (~ 30000 km2 moderate sensitivity) and the Dobrogea Plateau (~ 4150 km2 high sensitivity), in terms of the natural criterion, and in Braila (~ 4200 km2 moderate sensitivity) and Constanta (~ 3200 km2 high sensitivity) counties, in terms of the anthropogenic one. It was also found that land degradation in these areas corresponds to desertification, considering the existence of dry sub-humid and semi-arid climates, which are components of dryland systems.
6
Gad, A., and Rania Mansour. "Index Integrating Soil, Vegetation, Climate and Management Qualities to Evaluate Desertification in the Northwestern Coast, Egypt." International Journal of Environmental Engineering and Development 1 (December 18, 2023): 250–65. http://dx.doi.org/10.37394/232033.2023.1.23.
Анотація:
In Egypt, the phenomenon of desertification is a geographical phenomenon that is related to the decline or deterioration of the land's biological production capacity, which will eventually result in semi-desert conditions, or, in other words, the loss of fertility from productive lands. An understanding of the geographical distribution of environmentally sensitive areas (ESAs) is necessary for sustainable land use in the dry lands. The characteristics of the research region and the Mediterranean desertification and land use (MEDALUS) approach were used to evaluate the environmental sensitivity to desertification on the west-north coast of Egypt. Remote sensing images, topographic data, soils, and geological data are used to calculate desertification indicators. A hotspot of desertification risk exists on the north coast of Egypt due to soil degradation, climatic conditions, geomorphological and topographic features, soil quality and soil uses in each area. In each of these areas, these variables lead to varying levels and causes of soil degradation and desertification, as well as varying environmental, economic, and social effects. The obtained data reveal that (10.6%, 82.73%) of the west north coast are Sensitive and Very sensitive areas to desertification, About 1.22% of the research area is the moderately sensitive area, while the low sensitive and very low exhibit only (4.21,1.48) %. Remote sensing and GIS are recommended to monitor sensitivity. MEDALUS factors can be modified to obtain more reliable data at the local level.
7
OURABIT, Souad, Abderrahim ETTAQY, and Mohamed EL GHACHI. "ASSESSMENT OF SENSITIVITY TO DESERTIFICATION IN THE OUM ER-RBIA WATERSHED (UPSTREAM OF OULED SIDI DRISS) USING THE MEDALUS APPROACH." Journal of Applied Life Sciences and Environment 57, no. 1(197)2024 (March 25, 2024): 149–68. http://dx.doi.org/10.46909/alse-571129.
Анотація:
The issue of desertification is a pressing concern for many vulnerable regions, with consequences that extend far beyond their borders. It is a silent force that not only contributes to global climate change by releasing stored carbon from vegetation and soil but also compounds the ongoing environmental challenges we face on a global scale. In Morocco, the effects of these climate changes are already noticeable, particularly in terms of water scarcity due to reduced rainfall and rising temperatures. This, in turn, leads to soil drying and an increased risk of degradation. The Oum Er-Rbia watershed (upstream of Ouled Sidi Driss) is one of the basins affected by this issue, covering an area of 11,152 km² and spanning three topographic units (the Middle Atlas Mountains, the Phosphate Plateau and the Tadla Plain). This topographic diversity causes regional variation in the sensitivity to desertification. Therefore, this study aims to evaluate the sensitivity to desertification in this watershed by using the MEDALUS model (Mediterranean desertification and land use), which calculates the Desertification Sensitivity Index (DSI) through the composition of four indices: the Soil Quality Index (SQI), the Vegetation Quality Index (VQI), the Climate Quality Index (CQI) and the Land Use Quality Index (LUQI). The results show that the critical and highly sensitive zones represent 44% and are located at the northeast and west ends of the watershed. By contrast, the unaffected zones represent 12% of the total area of the watershed and correspond to the upstream area, where the climate, vegetation and land use systems are of good quality, providing effective protection for the land. To reduce the impact of this phenomenon, we have proposed some potentially impactful development actions based on land use and the results obtained.
8
Ait Lamqadem, Atman, Biswajeet Pradhan, Hafid Saber, and Abdelmejid Rahimi. "Desertification Sensitivity Analysis Using MEDALUS Model and GIS: A Case Study of the Oases of Middle Draa Valley, Morocco." Sensors 18, no. 7 (July 11, 2018): 2230. http://dx.doi.org/10.3390/s18072230.
Анотація:
Oases can play a significant role in the sustainable economic development of arid and Saharan regions. The aim of this study was to map the desertification-sensitive areas in the Middle Draa Valley (MDV), which is in the southeast of Morocco. A total of 13 indices that affect desertification processes were identified and analyzed using a geographic information system. The Mediterranean desertification and land use approach; which has been widely used in the Mediterranean regions due to its simplicity; flexibility and rapid implementation strategy; was applied. All the indices were grouped into four main quality indices; i.e., soil quality; climate quality; vegetation quality and management quality indices. Each quality index was constructed by the combination of several sub-indicators. In turn; the geometric mean of the four quality index maps was used to construct a map of desertification-sensitive areas; which were classified into four classes (i.e., low; moderate; high and very high sensitivity). Results indicated that only 16.63% of the sites in the study were classified as least sensitive to desertification; and 50.34% were classified as highly and very highly sensitive areas. Findings also showed that climate and human pressure factors are the most important indicators affecting desertification sensitivity in the MDV. The framework used in this research provides suitable results and can be easily implemented in similar oasis arid areas.
9
Boudjemline, Fouzia, and Ahcene Semar. "Assessment and mapping of desertification sensitivity with MEDALUS model and GIS – Case study: basin of Hodna, Algeria." Journal of Water and Land Development 36, no. 1 (March 1, 2018): 17–26. http://dx.doi.org/10.2478/jwld-2018-0002.
Анотація:
AbstractIn Algeria, desertification risk is one of the main environmental and also social and economic problems. As much as 20 million hectares of northern Algeria are highly exposed and vulnerable to desertification with large areas falling into his ‘severe’ risk category, because the present massive destruction of vegetation and soils. This study aimed to use geographic information system (GIS) for mapping environmentally sensitive areas to desertification based on Mediterranean Desertification and Land Use (MEDALUS) approach in basin of Hodna, Algeria. Sensitivity is estimated with a modification of the MEDALUS environmentally sensitive area index (ESAI) which identifies such areas on the basis of an index (ESAI) that incorporates data on environmental quality (climate, vegetation, soil) as well as anthropogenic factors. This methodology allows the classification of land in critical, fragile and potentially sensitive areas. The results obtained show that 61% of the area is classified potentially sensitive to low sensitivity. These areas are particularly located in mountain areas. Spatially, the areas sensitive to degradation are as well in the lower region of the Hodna in Highlands consisting mostly of steppe route. The factors that could explain these variations of sensitivity are related mainly to changes in precipitation between the North and the South altitude and pressure of the population and livestock.
10
Morianou, G. G., N. N. Kourgialas, G. Psarras, and G. C. Koubouris. "Mapping sensitivity to desertification in Crete (Greece), the risk for agricultural areas." Journal of Water and Climate Change 9, no. 4 (September 3, 2018): 691–702. http://dx.doi.org/10.2166/wcc.2018.148.
Анотація:
Abstract The objective of this work was to classify and map the areas environmentally sensitive to desertification in the Mediterranean island of Crete. Sensitivity to desertification was estimated with a modification of the MEDALUS Environmentally Sensitive Area Index (ESAI) approach, using 15 quantitative parameters divided into four main quality indices: climate, vegetation, soils and management quality. The ESAI methodology was modified to include two additional parameters related to soil quality (water erosion and soil organic matter). According to the results, 37% of the island's area is characterized as critically sensitive to desertification. This percentage varies significantly across the island, with the western part having the least critically sensitive areas, and the eastern part the most critically sensitive. The results of this study also indicate that critically sensitive areas are found in the eastern side of the island mainly due to human-related factors and climatic conditions. It was concluded that the proposed methodology is a valuable tool for regional-scale assessment of areas environmentally sensitive to desertification in Mediterranean environments.
11
Ahmed, A., S. Abba, F. Siriki, and B. Maman. "Quantitative Assessment of Land Cover Sensitivity to Desertification in Maigatari Local Government Area, Jigawa State, Nigeria." Journal of Applied Sciences and Environmental Management 24, no. 9 (October 16, 2020): 1509–17. http://dx.doi.org/10.4314/jasem.v24i9.4.
Анотація:
Desertification alludes to land degradation in arid, semi-arid and sub-humid regions resulting from various variables, counting climatic variations and human activities. When land degradation transpire within the world’s drylands. It regularly makes desert-like conditions. Land degradation occurs all over, but is characterized as desertification when it occurs within the drylands. The study employed adjusted MEDALUS methodology using eleven indicators rainfall, evapotranspiration, aridity, soil texture, soil depth, slope gradient, drainage density, plant cover, erosion protection, sensitivity desertification index and Normalized Difference Vegetation Index (NDVI). Remote Sensing and GIS were the main techniques used in the indices computations and mapping. Thus, Shuttle Rader Topographic Map (SRTM) and Landsat 8 satellite imagery for the year 2019 with 30 meter resolution, captured in the month of August (rainy season), covering the study area were acquired from Global Land cover Facility (GLCF) University of Maryland. The study finds that the duration and intensity of rainfall is declining especially at the edge of the desert, extreme north and western part of the area. Rain quickly drained through infiltration and surface runoff which carried the little nutrients attached to the soil. Rainfall and climate is of arid type recording about 300-400mm of rainfall and the soil is low in organic matter content making it weak and less fertile and support only the cultivation of cereals and legumes. The study recommends that there is need to strengthen the laws and policies in controlling desertification and land degradation, establishment of shelterbelts to control desertification and act also as wind breakers and encourage the use of modern techniques such as drip irrigation to check the rate of infiltration and runoff.
Keyword: Desertification; Sensitivity; MEDALUS; GIS; Maigatari
12
Morianou, G., N. N. Kourgialas, V. Pisinaras, G. Psarras, and G. Arambatzis. "Assessing desertification sensitivity map under climate change and agricultural practices scenarios: the island of Crete case study." Water Supply 21, no. 6 (May 6, 2021): 2916–34. http://dx.doi.org/10.2166/ws.2021.132.
Анотація:
Abstract The aim of this study is the assessment of desertification risk for a typical Mediterranean island, in the frame of climate change and the application of good agricultural practices. Based on the MEDALUS Environmentally Sensitive Area Index (ESAI) approach, the sensitivity in desertification is estimated by employing 15 quantitative parameters divided in to four main quality indices: climate, vegetation, soil, and management quality. The methodology applied for a baseline scenario (current conditions), two future climate change scenarios (RCP 4.5 and RCP 8.5) and a soil quality improvement scenario. According to the results, more than 13% of the island's area is characterized as critically sensitive to desertification in the current conditions. This percentage will increase in the future under both the RCP 4.5 and the RCP 8.5 climate scenarios, where the critical areas will rise above to 15%. By applying the soil quality improvement scenario simultaneously with the climate change scenarios, a slight mitigation of desertification risk in the future could be achieved. The methodology developed in this study may be used to assess desertification process under various climate, soil, and land use management scenarios in regions of the Mediterranean Sea.
13
& et al., Hamad. "ASSESSMENT OF ENVIRONMENTAL SENSITIVITY TO DESERTIFICATION WITH MEDALUS MODEL IN GIS IN MAYMONA PROJECT- SOUTH OF IRAQ." IRAQI JOURNAL OF AGRICULTURAL SCIENCES 52, no. 4 (August 22, 2021): 1058–69. http://dx.doi.org/10.36103/ijas.v52i4.1417.
Анотація:
The objective of this study was to identify the locations sensitivity to land desertification based on the Mediterranean Desertification and Land Use (MEDALUS) approach by the Geographic Information Systems (GIS) in the south of Maysan governorate at Iraq for mapping environmentally sensitive areas to desertification. Three indicators, which included climate, vegetation, and soil, were employed to estimate the ESAI and then to classify the land in critical, fragile potentially, and non-influenced sensitive areas. The results of the soil quality index (SQI) indicated that 25% of the studied area was classified as moderate quality and 21% was low quality while 54% was very low quality. Vegetation qualities were classified into moderate and low quality 19% and 81%, respectively, and climate quality was classified as moderate.
14
Dwivedi, Chandra Shekhar, Dishant, Bikash Ranjan Parida, Arvind Chandra Pandey, Ravi Kumar, and Navneet Kumar. "Geoinformatics-Based Mapping of Environmental Sensitive Areas for Desertification over Satara and Sangli Districts of Maharashtra, India." GeoHazards 5, no. 2 (May 17, 2024): 415–40. http://dx.doi.org/10.3390/geohazards5020022.
Анотація:
Desertification processes in arid, semi-arid, and dry sub-humid conditions have been enhanced in recent decades. The geospatial database and associated satellite data can be effectively employed for regional planning to address desertification and land degradation. In this study, the Mediterranean Desertification and Land Use (MEDALUS) model has been used to map environmentally sensitive areas due to desertification in the Satara and Sangli districts of Maharashtra, India. This was achieved by combining Landsat-8 multispectral data, Census data, soil data, and climatic variables like temperature, rainfall, and evapotranspiration. The algorithm of MEDALUS is the geometric mean of four indicators, namely soil quality index (SQI), climate quality index (CQI), vegetation quality index (VQI), and socio-economic quality index (SEQI). The findings indicated that the majority of the study area comes under the potential category of desertification (60.32%) followed by fragile (27.87%) and critical (11.81%). Areas with a high propensity for desertification were found over the low to very low climatic quality and moderate to high soil quality including lower socio-economic quality. The lower socio-economic quality is mainly due to high to very high population density (>100 people/km2), low to moderate illiteracy rate (<16%), and low to moderate work participation rate (<50%) that incentivize unsustainable land use practices. The study provides a valuable tool for understanding and managing natural resources. It offers a detailed analysis of the environmental sensitivity of the study area, taking into account various factors like land use, vegetation cover, slope, and soil erosion potential. The developed comprehensive map of the area helps in identifying the most sensitive regions and developing appropriate conservation strategies. The information obtained from the study can be utilized to develop and implement successful measures to prevent or alleviate desertification, which is crucial for sustaining the health of ecosystems and the welfare of local residents.
15
Wijitkosum, Saowanee. "Reducing Vulnerability to Desertification by Using the Spatial Measures in a Degraded Area in Thailand." Land 9, no. 2 (February 10, 2020): 49. http://dx.doi.org/10.3390/land9020049.
Анотація:
The process of desertification is complex, involving interaction between many factors, both environmental and anthropogenic. However, human activities, especially from land-use change and inappropriate land use, are the most influential factors associated with the desertification risk. This study was conducted in Huay Sai, a degraded land in Thailand. The Environmentally Sensitive Area Index (ESAI) model incorporating Geogracphic Information System (GIS) was applied to investigate and map the desertification sensitivity area. The study aimed to analyze and assess measures to reduce the desertification risk. This study emphasized three group factors with nine subcriteria influencing desertification risk: soil (texture, fertility, drainage, slope gradient, and depth), climatic (precipitation and aridity index), and vegetation factors (land use and soil erosion). In terms of the required spatial measures to reduce the desertification vulnerability, policy and defensive measures that were closely related to drought and desertification of the area were considered. Three main measures covering soil and water conservation, soil improvement, and reforestation were implemented. The area development and restoration plans have been implemented continuously. The study found that 47.29% of the Huay Sai area was at a high risk, with a further 41.16% at a moderate risk. Implementation of three measures indicated that desertification risk was significantly decreased. Addressing the causes of the highest risk areas could help reduce the overall desertification risk at Huay Sai, where most areas would then be at either a moderate (61.04%) or low (32.43%) desertification risk with no severe- or high-risk areas. The success of the area restoration is from the formulation of a restoration and development plan that understands the local conditions. Moreover, the plan integrated the restoration of the soil, forests, and water together in order to restore the ecosystem so that the implementation was able to solve problems directly.
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& Hussien, Khalaf. "ENVIRONMENT SENSITIVITY MAPS OF LAND DEGRADATION AND DESRTIFICATION USING MEDULAS MODEL AND REMOTE SENSING IN SHIRQAT CITY/IRAQ." IRAQI JOURNAL OF AGRICULTURAL SCIENCES 52, no. 3 (June 22, 2021): 697–711. http://dx.doi.org/10.36103/ijas.v52i3.1361.
Анотація:
This research of aims to study environment sensitivity of desertification and land degradation using MEDULAS project and remote sensing in AL-Shirqat City/Salahadin/Iraq. A 10 soil pedons were chosen from study area depending on difference in soil preperties, landuse and causes of desertification and degradation as (Salinity, Erosion, Gypsum and vegetation cover). Soil profile description, soil samples and GPS were conducted. The physical (texture) and chemical (CaCO3, CaSO4.2H2O, O.M, EC and pH) properties were determined. The Soil were classified as Torrifluvents in the (P1, P2, P3), Torripsamments in the (P5 and P7), Calcigypsids in the (P6, P8 and P10) and Calcids in the P4. The landsat 8 image at 20sep. 2019 and 19 sep. 2013 were aquired in the spectral indices calculate and spatial maps by using ERDAS 15 and GIS 10.2. The result show contrast in soil propreties as sand, clay, soil gypsum, CaCO3, OM and EC that reflect on Soil Quality Index (SQI) which were (60)% poor quality and (40)% moderate quality degradation. While (19.10) % that moderate quality and 80.90% that poor quality for Vegetation Quality Index. The results show that 0.1% of the study area is classified as C1; 25.35% as C2; 74.55% of the areas as C3. The spectral indices as LAI, SI5, OSAVI were approporiate for monitor of desertification and degradation in study area. Add, spatial change in the spectral indices as NDVI and LAI. The results shown that MEDALUS model is a important model in the areas disposed to desertification and degradation.
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Li, Chun, and Jin Ping Qian. "Comprehensive Evaluation on Sensitivity of Ecological Environment in Chengde." Advanced Materials Research 518-523 (May 2012): 1252–63. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.1252.
Анотація:
This paper adopts the multi-factor comprehensive evaluation to conduct spatial superposition calculation of the classified index of single-factor evaluation result through evaluating soil erosion sensitivity, land desertification sensitivity, susceptibility to stress of water resource and water environment pollution sensitivity, etc, thus getting the result of comprehensive evaluation of ecological environment sensitivity in Chengde. Chengde’s ecological environment has four levels which are extremely sensitive area, medium sensitive area, slightly sensitive area and general area.
18
Fadl, Mohamed E., Ahmed S. Abuzaid, Mohamed A. E. AbdelRahman, and Asim Biswas. "Evaluation of Desertification Severity in El-Farafra Oasis, Western Desert of Egypt: Application of Modified MEDALUS Approach Using Wind Erosion Index and Factor Analysis." Land 11, no. 1 (December 30, 2021): 54. http://dx.doi.org/10.3390/land11010054.
Анотація:
Desertification is a serious threat to human survival and to ecosystems, especially to inland desert oases. An assessment of desertification severity is essential to ensure national sustainable development for agricultural and land expansion processes in this region. In this study, Index of Land Susceptibility to Wind Erosion (ILSWE) was integrated with a Modified Mediterranean Desertification and Land Use (MEDALUS) method and factor analysis (FA) to develop a GIS-based model for mapping desertification severity. The model was then applied to 987.77 km2 in the El-Farafra Oasis, located in the Western Desert of Egypt, as a case study. Climate and field survey data together with remote sensing images were used to generate five quality indices (soil, climate, vegetation, land management and wind erosion). Based on the FA, a weighted value was assigned to each index. Five thematic layers representing the indices were created within the GIS environment and overlaid using the weighted sum model. The developed model showed that 59% of the total area was identified as high-critical and 38% as medium-critical. The results of an environmentally sensitive area index suggested by the original MEDALUS model indicated similar results: 18.37% of the total area was classified as high-critical and 78.73% as medium-critical. However, the sensitivity analysis indicated that weights derived from FA resulted in better performance of the developed spatial model than that derived from the original MEDALUS method. The proposed model would be a suitable tool for monitoring vulnerable zones, and could be a starting point for sustainable agricultural development in inland oases.
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Zheng, Wei, Chengjiao Rao, Qian Wu, Enwen Wang, Xingjian Jiang, Yichen Xu, Lei Hu, Yazhen Chen, Xiaocui Liang, and Wende Yan. "Changes in the Soil Labile Organic Carbon Fractions following Bedrock Exposure Rate in a Karst Context." Forests 13, no. 4 (March 27, 2022): 516. http://dx.doi.org/10.3390/f13040516.
Анотація:
Soil labile organic carbon fractions (SLOCFs) mainly include microbial biomass carbon (MBC), dissolved organic carbon (DOC), easily oxidized organic carbon (EOC) and light fraction organic carbon (LFOC). The link between bedrock exposure rates with SLOCFs and the carbon pool management index under karst rocky desertification has not been well understood. We selected the bedrock exposure rate and vegetation coverage of 30–50% (light bedrock exposure, LBE), 50–70% (moderate bedrock exposure, MBE) and >70% (intense bedrock exposure, IBE) as the experimental sample plots according to the classification standard of karst rocky desertification, and then selected a sample plot of 0–30% (secondary forest, SF) as the control. This study compared the concentrations and stocks of soil organic carbon (SOC) and SLOCFs and analyzed the relevant carbon pool management index on karst landforms at Anshun, S.W. China. The aims were to determine the relationship between bedrock exposure rates and SLOCFs and to identify the most limiting factors for SLOCFs in karst rocky desertification areas. We found that (1) the concentrations and stocks of SLOCFs declined with increasing soil depth. SOC, DOC and MBC showed IBE > LBE > MBE > SF; LFOC decreased with increasing bedrock exposure rate, and EOC did not show obvious regularity. (2) The carbon pool management index and sensitivity index had significant differences under different bedrock exposure rates. Redundancy analysis and linear regression showed that the increase in bedrock exposure rate had a great impact on MBC, DOC, EOC and SOC. In conclusion, the increase of bedrock exposure rate has no side impact on the DOC, EOC and MBC of the soil, but side effects are exhibited by LFOC. Secondary forest improves the integrity of karst landscapes, and does not change the soil properties as well as the concentrations and stocks of SLOCFs in karst rocky desertification areas.
20
Yahaya, Olanrewaju Y. "Assessment of Farm Households’ Vulnerability to Desertification in Rural Dry Lands of Katsina State, Nigeria." Tanzania Journal of Science 47, no. 3 (August 14, 2021): 1007–19. http://dx.doi.org/10.4314/tjs.v47i3.12.
Анотація:
The purpose of this study was to use a Vulnerability Index (VI) to assess farm households' vulnerability to desertification in Northern Katsina's dry land ecosystem. The specific objectives were to identify socio-economic characteristics of farm households; and determine the degree of their vulnerability to desertification. A systematic random sampling technique was used to select 633 respondents from 18 rural communities across six Local Government Areas (LGAs). Data from 21 indicators for the three components of vulnerability (exposure, sensitivity and adaptive capacity) were used to measure the degree of vulnerability and thus, classify households into less, moderate and highly vulnerable. The study found that households in Jibia LGA were less vulnerable, with a VI of 1.228, while Kaita, Mashi, and Mai'adua LGAs were moderately vulnerable with VI of 0.523, 0.756, and 0.685, respectively. Households in Zango and Baure LGAs were found to be highly vulnerable due to poor biophysical conditions, with indices of 1.629 and -1.405, respectively. Furthermore, while 49% of the total households sampled were moderately vulnerable to desertification, 30% were less vulnerable and 21% were found to be highly vulnerable. As a result, the study recommended that the need for vegetative cover regeneration, soil quality rehabilitation, increased irrigation use, and biomass stability that take into account the vagaries of climate be prioritized in order to support, rescue, and increase the resilience of vulnerable households.
Keywords: Adaptation; Desertification; Dry lands; Farm Households; Vulnerability Index
21
Aslanov, Ilhomjon, Sayidjakhon Khasanov, Yakhshimurad Khudaybergenov, Michael Groll, Christian Opp Ch, F. Li, and Ramirez Del-Valle E. "Land cover-adjusted index for the former Aral Sea using Landsat images." E3S Web of Conferences 227 (2021): 02005. http://dx.doi.org/10.1051/e3sconf/202122702005.
Анотація:
The Aral Sea was the fourth largest inland lake on the globe until 1960, with a surface area of about 68,000 km2. Mainly, the huge irrigation projects in many parts of its transboundary catchment were responsible for the catastrophic desiccation and ecological crises of the Aral Sea after second part of 20th century. Ecological crisis surrounding the Aral Sea (lake) regions is one of the critical environmental problems of Central Asia. As a result, monitoring of desertification processes and determining the aerosol concentration in the atmosphere are highly relevant for any attempts to mitigate environmental changes in the Aral Sea basin. Remote sensing is the most appropriate method for studying desertification and dust storms as it easily covers large areas with a high spatial and temporal resolution. Satellite images provide detailed multispectral information about the earth’s surface features, which proves invaluable for the characterization of vegetation, soil, water, and landforms at different scales. Vegetation cover, biomass, and soil properties were analyzed with remote sensing methods (NDVI, SDVI). It is emphasized that vegetation indices have little sensitivity at low leaf area which is common to all desert ecosystems.
22
Becker, Francois, and Bhaskar J. Choudhury. "Relative sensitivity of normalized difference vegetation Index (NDVI) and microwave polarization difference Index (MPDI) for vegetation and desertification monitoring." Remote Sensing of Environment 24, no. 2 (March 1988): 297–311. http://dx.doi.org/10.1016/0034-4257(88)90031-4.
23
Vieira, Rita Marcia da Silva Pinto, Javier Tomasella, Ana Paula Martins do Amaral Cunha, Alexandre Augusto Barbosa, João Pompeu, Yara Ferreira, Fabrícia Cristina Santos, Lincoln Muniz Alves, and Jean Ometto. "Socio-Environmental Vulnerability to Drought Conditions and Land Degradation: An Assessment in Two Northeastern Brazilian River Basins." Sustainability 15, no. 10 (May 15, 2023): 8029. http://dx.doi.org/10.3390/su15108029.
Анотація:
Over the past few decades, a significant amount of agricultural land has been lost due to soil degradation/desertification. In addition, the increasing frequency of extreme events, such as intense droughts and forest fires, has negatively impacted various ecosystem services. Two of the main Brazilian biomes—the Cerrado and the Caatinga—have been affected by increased rainfall variability, leading to desertification, increased fire frequency, and, consequently, rising concerns regarding the water and food security of the local population. In this study, we develop a methodology to assess these impacts using a Socio-Environmental Vulnerability Index (SEVI) that combines physical, environmental, and socio-economic indicators related to exposure, sensitivity, and adaptation, as well as including socio-environmental feedback. The developed SEVI is then applied to the São Francisco and Parnaíba river basins. The proposed index is based on the MEDALUS methodology and is adapted to include multiple biological, physical, and socio-economic indicators, allowing for the discrimination of areas characterized by different levels of vulnerability. We also analyze the effectiveness of governmental policies, such as the creation of conservation areas and the rural registration of properties, in reducing vulnerability. The SEVI analysis highlights that adaptive capacity is the main constraint for reducing socio-environmental vulnerability in the Parnaíba basin, while exposure and sensitivity are the greater challenges in the São Francisco basin. The results of this study are crucial for the prioritization of recovery actions in degraded areas.
24
Zhang, Le, Kangning Xiong, and Panteng Wan. "Effects of Heavy Metals on Nitrogen in Soils of Different Ecosystems in the Karst Desertification of South China." Forests 14, no. 7 (July 21, 2023): 1497. http://dx.doi.org/10.3390/f14071497.
Анотація:
Nitrogen, as a crucial limiting nutrient in terrestrial ecosystems, plays a vital role in determining land quality. Heavy metals, as drivers of soil substance transformation, are important indicators for assessing ecosystem function. Currently, the relationship between soil nitrogen and heavy metals in karst desertification areas remains unclear. Therefore, this study focuses on the soil of grassland, forest, and agroforestry ecosystems in a karst desertification area to investigate the relationship between heavy metals and nitrogen distribution using ecological stoichiometry. The findings revealed the following: (i) Total nitrogen (TN) and available nitrogen (AN) exhibited the trend of agroforestry * > forest > grassland, while soil microbial biomass nitrogen (SMBN) showed the trend of forest * > grassland * >> agroforestry; (ii) Chromium (Cr), Ferrum (Fe), Niccolum (Ni), and Plumbum (Pb) showed the trend of agroforestry * > grassland > forest, while Cuprum (Cu) demonstrated the trend of agroforestry > grassland > forest, and Zincum (Zn) exhibited the trend of grassland > forest * >> agroforestry. The Nemerow comprehensive pollution index were 0.77 for grassland, 0.69 for forest, and 0.94 for agroforestry; (iii) The sensitivity of soil nitrogen and heavy metals ranked as grassland > agroforestry > forest. The research findings aim to provide a scientific reference for karst desertification control, ecological protection and restoration, and enhancement of ecosystem function.
25
Ying, Bin, Ting Liu, Li Ke, Kangning Xiong, Sensen Li, Ruonan Sun, and Feihu Zhu. "Identifying the Landscape Security Pattern in Karst Rocky Desertification Area Based on Ecosystem Services and Ecological Sensitivity: A Case Study of Guanling County, Guizhou Province." Forests 14, no. 3 (March 19, 2023): 613. http://dx.doi.org/10.3390/f14030613.
Анотація:
Ecological environmental security in karst areas is an issue of global concern. Identifying the ecological landscape security pattern (ELSP) is key to promoting environmental protection and alleviating the land development and utilization impacts. Ecological sources (ESs) and ecological corridors (ECs) are important bases for constructing an ELSP. We used five influencing factors (land use type, digital elevation model (DEM), rocky desertification degree, normalized difference vegetation index (NDVI) and slope) to obtain the distribution of the importance and sensitivity values of ecosystem services in Guanling County, Guizhou Province. The probability of the connectivity index (PC) was calculated, and the ES was extracted by combining the importance of ecosystem services, ecological sensitivity, and landscape connectivity. According to the topographic and geomorphological characteristics of Guanling County, seven indicators of elevation, slope, landscape type, degree of stone desertification, distance from rivers, distance from settlements, and distance from roads were selected as resistance factors for the outward expansion of the ESs to calculate the comprehensive resistance surface of Guanling County. Based on the gravity model, an interaction matrix between 10 ESs was constructed, and the magnitude of the interaction forces between the source sites was quantitatively evaluated to distinguish the important ECs and general ECs. The study showed that the total length of the ECs in Guanling County was 509.78 km, and the core area of Guanling County was large, accounting for 65.73% of the ecological landscape area. By assessing the importance of ecosystem services, ecological sensitivity, and landscape connectivity, 10 ES and 45 EC were obtained based on ArcGIS10.8, which constituted the landscape security pattern of Guanling County by ESs and ECs. Suggestions were proposed for a planning layout that will benefit the ecological restoration of Guanling County and environmental protection of the karst region according to the study area characteristics.
26
Rashed, Heba. "Assessment of Environmental Sensitivity Index to Desertification Using GIS: Case Study in West El-Minia Governorate, Egypt." Journal of Soil Sciences and Agricultural Engineering 11, no. 12 (December 1, 2020): 719–26. http://dx.doi.org/10.21608/jssae.2020.159768.
27
Gül, Ebru, and Sabit Erşahin. "Evaluating the desertification vulnerability of a semiarid landscape under different land uses with the environmental sensitivity index." Land Degradation & Development 30, no. 7 (February 27, 2019): 811–23. http://dx.doi.org/10.1002/ldr.3269.
28
Symeonakis, Elias, Nikolaos Karathanasis, Sotirios Koukoulas, and George Panagopoulos. "Monitoring Sensitivity to Land Degradation and Desertification with the Environmentally Sensitive Area Index: The Case of Lesvos Island." Land Degradation & Development 27, no. 6 (April 3, 2014): 1562–73. http://dx.doi.org/10.1002/ldr.2285.
29
Halbac-Cotoara-Zamfir, Rares, Gloria Polinesi, Francesco Chelli, Luca Salvati, Leonardo Bianchini, Alvaro Marucci, and Andrea Colantoni. "Found in Complexity, Lost in Fragmentation: Putting Soil Degradation in a Landscape Ecology Perspective." International Journal of Environmental Research and Public Health 19, no. 5 (February 25, 2022): 2710. http://dx.doi.org/10.3390/ijerph19052710.
Анотація:
The United Nations Convention to Combat Desertification (UNCCD) assumes spatial disparities in land resources as a key driver of soil degradation and early desertification processes all over the world. Although regional divides in soil quality have been frequently observed in Mediterranean-type ecosystems, the impact of landscape configuration on the spatial distribution of sensitive soils was poorly investigated in Southern Europe, an affected region sensu UNCCD. Our study proposes a spatially explicit analysis of 16 ecological metrics (namely, patch size and shape, fragmentation, interspersion, and juxtaposition) applied to three classes of a landscape with different levels of exposure to land degradation (‘non-affected’, ‘fragile’, and ‘critical’). Land classification was based on the Environmentally Sensitive Area Index (ESAI) calculated for Italy at 3 time points along a 50-year period (1960, 1990, 2010). Ecological metrics were calculated at both landscape and class scale and summarized for each Italian province—a relevant policy scale for the Italian National Action Plan (NAP) to combat desertification. With the mean level of soil sensitivity rising over time almost everywhere in Italy, ‘non-affected’ land became more fragmented, the number of ‘fragile’ and ‘critical’ patches increased significantly, and the average patch size of both classes followed the same trend. Such dynamics resulted in intrinsically disordered landscapes, with (i) larger (and widely connected) ‘critical’ land patches, (ii) spatially diffused and convoluted ‘fragile’ land patches, and (iii) a more interspersed and heterogeneous matrix of ‘non affected’ land. Based on these results, we discussed the effects of increasing numbers and sizes of ‘critical’ patches in terms of land degradation. A sudden expansion of ‘critical’ land may determine negative environmental consequences since (i) the increasing number of these patches may trigger desertification risk and (ii) the buffering effect of neighboring, non-affected land is supposed to be less efficient, and this contains a downward spiral toward land degradation less effectively. Policy strategies proposed in the NAPs of affected countries are required to account more explicitly on the intrinsic, spatio-temporal evolution of ‘critical’ land patches in affected regions.
30
Perez-Aguilar, Lidia Yadira, Wenseslao Plata-Rocha, Sergio Alberto Monjardin-Armenta, Cuauhtémoc Franco-Ochoa, and Yedid Guadalupe Zambrano-Medina. "The Identification and Classification of Arid Zones through Multicriteria Evaluation and Geographic Information Systems—Case Study: Arid Regions of Northwest Mexico." ISPRS International Journal of Geo-Information 10, no. 11 (October 26, 2021): 720. http://dx.doi.org/10.3390/ijgi10110720.
Анотація:
Arid and semiarid regions are geographic units that cover approximately 43% of the earth’s surface worldwide, and conditions of extreme drought and reduced vegetation cover predominate in these regions. In Mexico, arid and semiarid ecosystems cover more than half of the territory, with desertification, mainly caused by anthropogenic activities and climatic events, as the main problem in these regions. The present research aimed to assess, identify, and classify arid and semiarid zones by employing a methodology based on multicriteria evaluation analysis (MCA) using the weighted linear combination (WLC) technique and geographic information systems (GIS) in the hydrological administrative regions (HARs) of the North Pacific, Northwest, and Baja California Peninsula, located in Northwest Mexico. Data related to aridity, desertification, degradation, and drought were investigated, and the main factors involved in the aridity process, such as surface temperature, soil humidity, precipitation, slopes, orientations, the normalized difference vegetation index (NDVI), and evapotranspiration, were obtained. For the standardization of factors, a fuzzy inference system was used. The weight of each factor was then determined with the analytical hierarchy process (AHP). To delimit arid regions, the classification of arid zones proposed by the United Nations Environment Program (UNEP) was used, and the result was an aridity suitability map. To validate the results, the sensitivity analysis method was applied. Quantitative and geospatial aridity indicators were obtained at the administrative hydrological level and by state. The main results indicated that semiarid and dry subhumid zones predominated, representing 40% and 43% of the surface of the study area, respectively, while arid regions represented 17%, and humid regions represented less than 1%. In addition, of the states for which 100% of the surface lay in the study area, it was observed that Baja California and Baja California Sur had the largest arid and semiarid zones, while subhumid regions predominated in Sonora and Sinaloa.
31
Niu, Xiaonan, Huan Ni, Qun Ma, Shangxiao Wang, and Leli Zong. "Identifying Ecological Security Patterns Based on Ecosystem Service Supply and Demand Using Remote Sensing Products (Case Study: The Fujian Delta Urban Agglomeration, China)." Sustainability 15, no. 1 (December 29, 2022): 578. http://dx.doi.org/10.3390/su15010578.
Анотація:
As the global population increases and cities expand, increasing social needs and ecosystem degradation generally coexist, especially in China’s urban agglomerations. Identifying ecological security patterns (ESPs) for urban agglomerations serves as an effective way to sustain regional ecological security and promote harmonious ecological conservation and economic development. Focusing on the Fujian Delta Urban Agglomeration (FDUA) as an example, this study aims to present a framework for linking the supply and demand of ecosystem services (ESs) to identify ESPs in 2020. First, the ecological sources are delimited by coupling the supply and demand of four critical ESs (carbon storage, water provision, grain production, and outdoor recreation). Afterward, the resistance coefficient is modified using nighttime light intensity data and the ecological risk index, the second of which combines the effects of the soil erosion sensitivity index, the geological disaster risk index, and the land desertification risk index. Then, ecological corridors are determined by employing the minimum cumulative resistance method. With the integration of ecological sources and corridors, the ESPs of the FDUA can be identified. The results show a distinct supply–demand mismatch for ESs, with supply exhibiting an upward gradient from coastal cities to inland mountain cities and demand showing the opposite trend. The ESPs consist of 8359 km2 of ecological sources that are predominantly forests, 171 ecological corridors with a total length of 789.04 km, 34 pinch points, 26 barriers, and 48 break points. This paper presents a realizable approach for constructing ESPs for urban agglomerations, which will help decision makers optimize ecological sources and ecological protection policies.
32
Li, Han, and Wei Song. "Spatiotemporal Distribution and Influencing Factors of Ecosystem Vulnerability on Qinghai-Tibet Plateau." International Journal of Environmental Research and Public Health 18, no. 12 (June 16, 2021): 6508. http://dx.doi.org/10.3390/ijerph18126508.
Анотація:
As the “Third Pole”, the Qinghai-Tibet Plateau is threatened by environmental changes. Ecosystem vulnerability refers to the sensitivity and resilience of ecosystems to external disturbances. However, there is a lack of relevant studies on the driving factors of ecosystem vulnerability. Therefore, based on spatial principal components analysis and geographic detectors methods, this paper evaluates the ecosystem vulnerability and its driving factors on the Qinghai-Tibet Plateau from the years 2005 to 2015. The results were as follows: (1) The ecosystem vulnerability index (EVI) of the Qinghai-Tibet Plateau is mainly heavy and extreme, showing a gradually increasing trend from southeast to northwest. (2) The spatial heterogeneity of the EVI is significant in the southeast and northwest, but not in the southwest and central parts. (3) Analysis of influencing factors shows that environmental factors have more significant effects on EVI than socioeconomic variables, facilitating the proposal of adequate policy implications. More efforts should be devoted to ecological protection and restoration to prevent grassland degradation and desertification in the high-EVI areas in northwest. The government is also urged to improve the ecological compensation mechanisms and balance ecological protection and residents’ development needs in the southeast.
33
Adane, Zablon, Vitaly A. Zlotnik, Nathan R. Rossman, Tiejun Wang, and Paolo Nasta. "Sensitivity of Potential Groundwater Recharge to Projected Climate Change Scenarios: A Site-Specific Study in the Nebraska Sand Hills, USA." Water 11, no. 5 (May 6, 2019): 950. http://dx.doi.org/10.3390/w11050950.
Анотація:
Assessing the relationship between climate forcings and groundwater recharge (GR) rates in semi-arid regions is critical for water resources management. This study presents the impact of climate forecasts on GR within a probabilistic framework in a site-specific study in the Nebraska Sand Hills (NSH), the largest stabilized sand dune region in the USA containing the greatest recharge rates within the High Plains Aquifer. A total of 19 downscaled climate projections were used to evaluate the impact of precipitation and reference evapotranspiration on GR rates simulated by using HYDRUS 1-D. The analysis of the decadal aridity index (AI) indicates that climate class will likely remain similar to the historic average in the RCP2.6, 4.5, and 6.0 emission scenarios but AI will likely decrease significantly under the worst-case emission scenario (RCP8.5). However, GR rates will likely decrease in all of the four emission scenarios. The results show that GR generally decreases by ~25% under the business-as-usual scenario and by nearly 50% in the worst-case scenario. Moreover, the most likely GR values are presented with respect to probabilities in AI and the relationship between annual-average precipitation and GR rate were developed in both historic and projected scenarios. Finally, to present results at sub-annual time resolution, three representative climate projections (dry, mean and wet scenarios) were selected from the statistical distribution of cumulative GR. In the dry scenario, the excessive evapotranspiration demand in the spring and precipitation deficit in the summer can cause the occurrence of wilting points and plant withering due to excessive root-water-stress. This may pose significant threats to the survival of the native grassland ecology in the NSH and potentially lead to desertification processes if climate change is not properly addressed.
34
Taghadosi, M. M., and M. Hasanlou. "TREND ANALYSIS OF SOIL SALINITY IN DIFFERENT LAND COVER TYPES USING LANDSAT TIME SERIES DATA (CASE STUDY BAKHTEGAN SALT LAKE)." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W4 (September 27, 2017): 251–57. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w4-251-2017.
Анотація:
Soil salinity is one of the main causes of desertification and land degradation which has negative impacts on soil fertility and crop productivity. Monitoring salt affected areas and assessing land cover changes, which caused by salinization, can be an effective approach to rehabilitate saline soils and prevent further salinization of agricultural fields. Using potential of satellite imagery taken over time along with remote sensing techniques, makes it possible to determine salinity changes at regional scales. This study deals with monitoring salinity changes and trend of the expansion in different land cover types of Bakhtegan Salt Lake district during the last two decades using multi-temporal Landsat images. For this purpose, per-pixel trend analysis of soil salinity during years 2000 to 2016 was performed and slope index maps of the best salinity indicators were generated for each pixel in the scene. The results of this study revealed that vegetation indices (GDVI and EVI) and also salinity indices (SI-1 and SI-3) have great potential to assess soil salinity trends in vegetation and bare soil lands respectively due to more sensitivity to salt features over years of study. In addition, images of May had the best performance to highlight changes in pixels among different months of the year. A comparative analysis of different slope index maps shows that more than 76% of vegetated areas have experienced negative trends during 17 years, of which about 34% are moderately and highly saline. This percent is increased to 92% for bare soil lands and 29% of salt affected soils had severe salinization. It can be concluded that the areas, which are close to the lake, are more affected by salinity and salts from the lake were brought into the soil which will lead to loss of soil productivity ultimately.
35
Zhao, Xiaoqing, Qifa Yue, Jianchao Pei, Junwei Pu, Pei Huang, and Qian Wang. "Ecological Security Pattern Construction in Karst Area Based on Ant Algorithm." International Journal of Environmental Research and Public Health 18, no. 13 (June 26, 2021): 6863. http://dx.doi.org/10.3390/ijerph18136863.
Анотація:
Constructing the ecological security pattern is imperative to stabilize ecosystem services and sustainable development coordination of the social economy and ecology. This paper focuses on the Karst region in southeastern Yunnan, which is ecologically fragile. This paper selects the main types of ecosystem services and identifies the ecological source using hot spot analysis for Guangnan County. An inclusive consideration of the regional ecologic conditions and the rocky desertification formation mechanism was made. The resistance factor index system was developed to generate the basic resistance surface modified by the ecological sensitivity index. The Ant algorithm and Kernel density analysis were used to determine ecological corridor range and ecological restoration points that constructed the ecological security pattern of Guangnan County. The results demonstrated that, firstly, there were twenty-three sources in Guangnan County, with a total area of 1292.77 km2, accounting for 16.74% of the total. The forests were the chief ecological sources distributed in the non-Karst area, where Bamei Town, Yangliujing Township and Nasa Town had the highest distribution. Secondly, the revised resistance value is similar to “Zhe (Zhetu Township)-Lian (Liancheng Town)-Yang (Yangliujing Township)-Ban (Bambang Township)”. The values were lower in the north and higher in the south, which is consistent with the regional distribution of Karst. Thirdly, the constructed ecological security pattern of the “Source-Corridor-Ecological restoration point” paradigm had twenty-three ecological corridors. The chief ecological and potential corridor areas were 804.95 km2 and 621.2 km2, respectively. There are thirty-eight ecological restoration points mainly distributed in the principal ecological corridors and play a vital role in maintaining the corridor connectivity between sources. The results provide guidance and theoretical basis for the ecological security patterns construction in Karst areas, regional ecologic security protection and sustainable development promotion.
36
Li, Chunhua, Jin Wang, Xincen Liu, and Kejian Xu. "Construction of Karst Landscape Ecological Security Pattern Based on Conflict between Human and Nature in Puzhehei." Sustainability 16, no. 2 (January 21, 2024): 908. http://dx.doi.org/10.3390/su16020908.
Анотація:
A key means of promoting the high-quality development of karst areas is the maintenance of the area’s ecological security. A full recognition of the special ecological function of karst areas, as well as their significance to the surrounding region’s ecological, economic, and social development, is crucial in strengthening the overall strategic deployment of the national ecological construction and the protection and sustainable development of karst landscapes around the globe. In this study, the karst landscape of Puzhehei, Qiubei County, Wenshan Prefecture, Yunnan Province, China, was used as the research object. This study identified ecological source sites through a combination of morphological spatial pattern analysis and landscape connectivity assessment. As a result, 10 factors were selected to construct a comprehensive ecological resistance surface from the natural environment and socio-economic perspective; the resistance surface was corrected by combining the sensitivity of rocky desertification. An ecological corridor and ecological nodes were identified to construct the ecological security pattern based on the minimum cumulative resistance model and circuit theory. The results show that (1) the source areas of the Puzhehei karst landscape ecological protection comprised 11 core area patches with the landscape connectivity index of (dPC) ≥ 10, with a total area of 166.6572 km2, which constituted 46.06% of the total study area, and the ecological source area totaled 77.275 km2, or 21.36% of the total study area; (2) there were 78 potential ecological corridors in the Puzhehei karst region, with a total length of 545.186 km, including 12 key corridors and 66 general corridors; (3) a total of 51 ecological nodes were identified, including 11 “source-type ecological nodes”, 30 “ecological pinch points”, and 10 “ecological obstacles”, including 16 key ecological nodes. This study provides a theoretical basis for the integration of Puzhehei Nature Reserve, as well as a reference for the ecologically sustainable development of similar karst areas.
37
Nguyen, Binh Thanh, Gai Dai Dinh, and Long Ba Le. "Spatial and temporal-trend assessment of desertification-sensitive land using the desertification sensitivity index in the provincial Ninh Thuan, Vietnam." Environmental Monitoring and Assessment 196, no. 6 (May 10, 2024). http://dx.doi.org/10.1007/s10661-024-12707-x.
38
Chen, Lulu. "Landscape ecological network construction method supported by high-precision GIS data." Applied Mathematics and Nonlinear Sciences 9, no. 1 (January 1, 2024). http://dx.doi.org/10.2478/amns-2024-1591.
Анотація:
Abstract With the acceleration of urbanization, the regional landscape pattern has undergone profound changes. This study combines green space ecology and explores the construction method of landscape ecological networks using the support of GIS data platform. After completing the extraction of landscape environmental information, it is fused and processed using principal component transformation, tasseled cap transformation, and vegetation index extraction. Different landscape pattern indices are utilized to construct a landscape analysis pathway based on the relevant data from high-precision GIS. Meanwhile, an ecological sensitivity evaluation method that includes soil erosion and rocky desertification was proposed. By comparing and analyzing the landscape pattern indices, it was concluded that the Shannon diversity index increased by 0.2927 and the Shannon evenness index increased by 0.0352, indicating that the landscape types of the study area gradually tend to be even in quantity and spatial distribution. In the evaluation of ecological sensitivity, the proportion of moderate and lower sensitivity reaches 69.28%, indicating that the ecological environment is relatively calm despite external disturbances.
39
Liu, Yang, Jiajun Huang, and Wei Lin. "Zoning strategies for ecological restoration in the karst region of Guangdong province, China: a perspective from the “social-ecological system”." Frontiers in Environmental Science 12 (February 16, 2024). http://dx.doi.org/10.3389/fenvs.2024.1369635.
Анотація:
Ecological restoration holds great significance in addressing environmental degradation and rock desertification in karst areas. Zoning strategy is a fundamental task in understanding the interrelationship between human-environment to foster sustainable development. We explore “social-ecological” system and conduct a case study on the karst region in Guangdong Province, China. An evaluation framework consists of “development pressure”, “sensitivity status”, and “resilience potential” was established. The results show that: regions with high pressure of development are predominantly located in high-density urban areas. The generally distribution of the comprehensive status index exhibits significant spatial heterogeneity. Regions with low sensitivity are found on the eastern and western sides of the study area. The comprehensive resilience values are largely influenced by per capita energy-saving and environmental protection expenditures. The restoration zones mainly concentrated in the contiguous regions of the northwestern and southern parts, covering more than half of the total area. The conservation zones are more numerous and primarily situated in the northern and eastern parts. By integrating socio-economic and ecological factors, this study proposes ecological restoration strategies for specific zones. It helps for improve development issues arising from complex interactions between human-environment, facilitating the implementation of restoration practices.
40
Gabriele, Marzia, Raffaella Brumana, Mattia Previtali, and Alberta Cazzani. "A combined GIS and remote sensing approach for monitoring climate change-related land degradation to support landscape preservation and planning tools: the Basilicata case study." Applied Geomatics, July 26, 2022. http://dx.doi.org/10.1007/s12518-022-00437-z.
Анотація:
AbstractMonitoring landscapes in times of climate change patterns is a crucial issue, moreover, in the analyzed Mediterranean area, one of the major global candidates to develop land degradation stresses and consequential desertification phenomena. The research presented here is developed in the Mediterranean Basin, specifically in the Basilicata Region (southern Italy). The region is characterized by a very long history of intensive anthropization endowed by the high diversity of relatively geologically young soil types that consequentially created a vastity of spatial mosaics, which contributed to the composition of its archeolandscapes and endorsed some specific characteristics of the Mediterranean region, that evolved to respond to the human impact, including grazing, cultivation, and fires. Those key elements lead to the crucial issues of the region investigated here as soil erosion, salinization, loss of organic carbon, loss of biodiversity, and landslides, which together with deforestations, depopulation, and wildfires, define the exact framework of degradation and marginality. The evaluation of the sensitivity to degradation was performed (i) firstly at the regional scale, through a MEDALUS (Kosmas et al. 1999) approach, by implementing 6 main indicators (Soil Quality Index, Climate Quality Index, Vegetation Quality Index, Management Quality Index, Landslide Risk Index, Water Availability Index), and (ii) secondly at the mid-regional scale, through remote sensing by evaluation of the NDVI differencing thresholds in time intervals, covering a 20 years’ time span going from 2000 to 2020. The study helped to define the in-progress land degradation trends and scenarios of the region, which must be the evidence-based foundation of integrated landscape planning strategies in marginal territories, implemented through a Decision Support System (DSS) based both on ecological, climate-adaptive, and environmental indicators, and on social, cultural, and economic development co-creation strategies.