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1.
Land elements like slope, soil depth, land use/land cover, water holding capacity, soil texture, soil erosion, elevation, potential of hydrogen, etc. determine the suitability for agriculture. Land suitability analysis is a one of the methods of assessment of detecting inherent capacities, potential and suitability levels of the lands for agriculture, and was utilized with the same land elements in this study. A multi-criterion decision making approach using IRS P6 LISS-IV satellite dataset within a GIS environment was used to identify suitable areas for agriculture in the Darna catchment. Experts’ opinions, literature review, and correlation technique were used to decide influencing criteria, assign scores to sub-criteria, and judgment formation in pairwise comparison matrix. All thematic layers of criteria were integrated with each other in GIS using the weighted overlay technique and generated agriculture suitability map into four classes according to FAO. About 23% of the area is under agriculture in the study region. This area can extend up to 69% under agriculture converting fallow land, scrub land, and sparse forest according to soil qualities with suitability levels, i.e., highly suitable (19%), moderately suitable (16%), and marginally suitable (34%). About 31% (19,219 ha) of reviewed area are classified in the class permanently “not suitable” for agriculture. Moderately and marginally suitable land requires the irrigation facility for efficient agriculture. This study emphasizes that about 46% area has potential as agriculture land and it will help improve the financial condition of the farmers.  相似文献   

2.
In arid and semi-arid regions without perennial water sources such as rivers or lakes, almost all water supply needs are met by groundwater. Groundwater recharge (GWR) is critical to maintain the abundance of groundwater. This paper presents a methodology based on a decision support system (DSS) that combines remote sensing, field survey and geographic information system techniques to identify suitable GWR areas. The DSS was implemented to obtain suitability maps and to evaluate the existing GWR in the study area. The DSS inputs comprised maps of rainfall surplus, slope, potential runoff coefficient, land cover/use and soil texture. The spatial extents of GWR suitability areas were identified by a hierarchical process analysis that considered five layers. The model generated a GWR map with four categories of suitability: excellent, good, moderate and poor and unsuitable. The spatial distribution of these categories showed that 0.08 and 32.3 % of the study area was classified as excellent and good for GWR, respectively, while 63.2 and 4.42 % of the area was classified as moderate and poor and unsuitable, respectively. Most of the areas with excellent to good suitability have slopes of between 4 and 8 % and are intensively cultivated areas. The major soil type in the excellent to good areas is loam, followed by clay loam, and the rainfall in these areas ranges from 150 to 260 mm. Another suitability model, in which all criteria were assigned equal influence, generated a suitability map in which 0.1 % of the study area was rated as excellent, 10.9 % as good, 82 % as moderate and 7 % as poor and unsuitable. The locations of existing GWR dams were compared with the locations indicated on the generated suitability map using the proximity analysis tool in ArcGIS 10.1. Most (77 %) of the existing GWR structures that were categorised as successful were within the excellent and good areas, followed by moderately suitable (23 %).  相似文献   

3.
The North-Western Coast of Egypt (NWCE) represents one of the high priority regions for future development in the country. El-Hammam area is located in the NWCE with an area of 94752 acres and is one of the main challenging regions for sustaianble development. In this study, we have used remote sensing and soil data in combination with GIS tools, for land use sustainable analysis (SLU) in El-Hammam area. The SLU was established based on various factors such as: land capability and suitability, water resources availability, economic return from water and financial return from land and water. A physiographic soil map for the study area was prepared using remote sensing and GIS. Multiple field surveys were carried out for collecting information on various soil map units (SMUs) and their profiles. Laboratory analysis for the collected samples was performed, and then the soil properties were stored as attributes in a geographical soil database linked with the SMUs. Furthermore, land capability assessment was done to define the suitable areas for agricultural production using a capability model built in ALES software. Results indicate that the area currently lacks high capability and moderate capability classes. By improving the soil properties, the soil can attain potential capability; and 55630 acres will become marginally capable. The assessment of soil physical suitability for different land use types (LUTs) were analysed in ALES software, in order to generate the most suitable areas. The results from the land suitability analysis indicated that, 17114 acres are moderately suitable for wheat and sorghum; whereas 15823 acres are moderately suitable for barley and 12752 acres are moderately suitable for maize, olive and figs. Finally, the SLU was investigated based on two scenarios; (1) the most SLU under the conditions of shortage of irrigation water: clover, barley and sorghum against figs, as the irrigation requirements for barley and sorghum are low; (2) the most sustainable land use in the conditions of irrigation availability will be wheat and maize against figs and guava. From the results it is quite evident that GIS combined with modeling approaches are powerful tools for decision making in the study area.  相似文献   

4.
Land suitability evaluation is prerequisite for assessing the limitations for sustainable land use planning. We used ten site specific criteria (rainfall, texture, drainage, soil depth, slope, distance to major road, distance to nearest sugar mill, erosion hazard, risk of flooding and pH) and applied weighted multi-criteria evaluation (MCE) technique in a geographic information system (GIS) environment to evaluate land suitability for sugarcane cultivation in Bijnor district, India. The weightage of all the parameters was calculated through fuzzy analytical hierarchy process. Sugarcane suitability map was prepared integrating various parameters through weighted overlay analysis. The map was categorized as highly suitable (S1), moderately suitable (S2), marginally suitable (S3) and unsuitable (N). The analysis revealed that of the total cultivable land of the district, largest area (61%) was highly suitable followed by moderately suitable (24%), marginally suitable (7%) and unsuitable (8%) for sugarcane cultivation. Nagina, Najibabad and Bijnor sub-districts need attention of land managers and policy makers to remove the limitations and increase the suitability of sugarcane in such areas. Only 7% area was unsuitable for sugarcane cultivation. Slope, soil depth and erosion hazard were the major limiting factors making the land unsuitable for sugarcane cultivation. Therefore, these areas should be given priority for land and soil restoration efforts. The study showed effectiveness of integrated GIS and MCE approach for land suitability analysis of sugarcane.  相似文献   

5.
In recent decades, the high population growth has increased the demand for agricultural lands and products. Groundwater offers reliability and flexibility in access to water for irrigation purposes, especially in arid and semi-arid areas, such as Amol-Babol Plain, Iran. However, the quality and quantity of groundwater may not be suitable for irrigation purposes in all areas due to urbanizations, and intensive agricultural and industrial activities. Groundwater suitability zoning for irrigation purposes could be useful to improve water resources and land use planning, mostly in areas with water scarcity. Therefore, a GIS-based indices method is proposed to assess suitable zones for agricultural activities, integrating the irrigation water quality (IWQ) index and hydrogeological factors. IWQ index was utilized to assess groundwater quality based on salinity hazard, infiltration hazard, specific ions, and trace elements hazards, and miscellaneous effects such as pH, bicarbonate, and nitrate. The potential of the aquifer for irrigation water abstraction was investigated using hydrogeological surveys such as slope angle of the plain, hydraulic conductivity, and aquifer thickness. The groundwater suitability index classified most of the study area (more than 90 %) as “excellent” or “good” suitability zones for irrigation purposes. A limited area of around 5.6 % of the total area has moderate suitability for irrigation purposes due to the Caspian Seawater intrusion and the presence of fossil saline water. The proposed methodology provides useful information in order to allow irrigation management to prevent water and soil deterioration.  相似文献   

6.
Groundwater is a valuable natural resource for drinking, domestic, livestock use, and irrigation, especially in arid and semi-arid regions like the Garmiyan belt in Kurdistan region. The Awaspi watershed is located 50 km east of Kirkuk city, south Kurdistan, Iraq; and covers an area of 2146 km2. The paper presents result of a study aimed at: (1) mapping and preparing thematic layers of factors that control groundwater recharge areas, and (2) determination of sites suitable for groundwater recharge. We used available data such as geological map, groundwater depth map, digital elevation model (DEM), Landsat 8 imagery, and tropical rainfall measuring mission (TRMM) data for this study. These data, supplemented by slope features, lithology, land use land cover, rainfall, groundwater depth, drainage density, landform, lineament density, elevation and topographic position index, were utilized to create thematic maps to identify suitable areas of groundwater recharge, using GIS and remote sensing techniques. Analytic hierarchy process (AHP) was applied to weight, rank, and reclassify these maps in the ArcGIS 10.3 environment, to determine the suitable sites for groundwater recharge within the Awaspi watershed. Fifty-five percent of the total area of the watershed was found to be suitable for groundwater recharge; whereas 45% of the area was determined to have poor suitability for groundwater recharge, but can be used for surface water harvesting.  相似文献   

7.
In most large and fast growing urban areas, finding suitable lands for construction of landfill is one of the serious problems in environmental management. Land fill site selection process depends on different factors, regulations and constraints. Ignoring each of these parameters may cause miscalculations and lead to selection of an inappropriate landfill site which could have negative environmental, economical, and ecological impacts. Therefore, this process must be accomplished by taking into account all of the related criterions and variables. In this study, landfill site selection is performed by combining geographic information system (GIS) and analytical hierarchy process (AHP) in Hamedan province, west of Iran. In relation to landfill site selection, ten different criteria including Geology, surface water, aquifer, land use, elevation, slope, and distance to main roads, residential areas, faults and sinkholes were investigated. Using AHP each criterion was weighted, then geographic information system (Arc GIS 9.3 software) was used to manipulate and present spatial data. Finally, suitability map was prepared by overlay analyses and most suitable and suitable areas were identified and checked in field. The results indicate that 60.4 % of the area in the Hamedan province (11,631 km2) is unsuitable, 33 % (6,257.7 km2) moderately suitable and 6.6 % (1,344 km2) most suitable for construction of landfill.  相似文献   

8.
根据研究区内地质环境特征,选取地貌类型、地面坡度、地下水位埋深、地下水腐蚀性、地基承载力、土体压缩模量和地质灾害易发性7个评价指标,利用层次分析法(AHP)和GIS空间分析对主城区建设用地适宜性进行了评价分析.结果表明,牡丹江市主城区建设用地适宜性良好,适宜区和较适宜区占主城区总面积的58.2%,并以主城区南部区域地质环境最为优越,建议牡丹江市适度向南发展,同时做好生态环境和永久基本农田的保护工作.  相似文献   

9.
In Egypt, major sustainability variables could be identified as scarce of soil and water resources, environmental degradation, rapid population growth, institutional arrangement that includes land tenure and farm fragmentation, agricultural administration, lack of infrastructure, and credit utilization. The main objective of the current work is to evaluate the sustainable land use management (SLM) model through biophysics and socioeconomic elements for the purpose of combating sustainability constraints that preclude the agricultural development geospatially. In this research, from the geomorphologic point of view, the obtained results showed three main landscapes. They were identified in the study area as: fluviolacustrine plain, Aeolian deposits, and flood plain. The study area was dominated by some physical and chemical degradation processes with different scales breaking down the equilibrium of soil stability. The SLM model was implemented and assessed from multivariate perspective points of productivity, security, protection, economic viability, and social acceptability. Four SLM classes were outlined as follows: class I, land management practices that did meet sustainability requirements with a score ≥0.65, which represented 31.0 % of the considered agricultural study area; class II, land management practices that were marginally above the sustainability threshold and represented 12.6 %; class III, land management practices that were slightly below the threshold of sustainability and represented 8.60 %; class IV, land management practices that did not meet sustainability requirements with index values >0.1 that represented 47.86 %. As a general conclusion, it is found that land management practices tend to be unsustainable in the area under investigation for certain constraints that play motivated roles in lowering the targeted land sustainability.  相似文献   

10.
国土空间开发适宜性评价是国土空间规划编制的重要基础,市县是落实主体功能区划的基本单元,市县级国土空间开发适宜性评价可为国土资源与空间更精细化的管理提供有效支撑。本研究从自然因素和社会经济因素两个方面构建了国土空间开发适宜性评价指标体系,对宜昌市农业生产适宜性及城镇建设适宜性进行了评价,划分出适宜、较适宜、一般适宜、较不适宜和不适宜5类区域。结果表明宜昌市适宜开展农业生产的土地面积为3412 km2,不适宜土地面积为7143 km2;适宜进行城镇建设的土地面积为748 km2,不适宜土地面积为14679 km2。农业生产和城镇建设适宜性评价结果均呈现出典型的区域特征,适宜区主要分布在东部的平原区,区域整体的国土空间开发条件好;不适宜区主要分布在西部山区,区域整体的国土空间开发难度大。适宜性评价结果与规划数据有部分出入,与土地利用现状相差不大,农业生产适宜等级的土地面积比耕地保有量红线面积多132 km2,分布于农业生产适宜和较适宜区的现状耕地占耕地总面积的73.98%;城镇建设适宜等级的土地面积比建设用地底线面积少611 km2,分布于城镇建设适宜和较适宜区的现状建设用地占建设用地总面积的77.99%。将评价结果叠加在谷歌卫星图上,在空间上观察是否与土地现状一致,结果表明农业生产适宜区的评价结果准确率达100%,不适宜区的准确率为93%;城镇建设适宜区和不适宜区评价结果准确率达100%。  相似文献   

11.
Studies on denudation processes and soil loss rates can provide insight into the landscape evolution, climate change, and human activities, as well as on land degradation risk. The aims of this study were to analyze the space–time distribution of denudation processes and evaluate the soil loss changes occurred during the period 1955–2016 by using an approach integrating geomorphological, geospatial and modeling analysis. The study area is a representative stream catchment of the Crati Valley (Calabria, southern Italy), which is affected by severe erosion processes. The combined use of aerial photographs interpretation, field survey, geostatistics, and GIS processing has allowed to characterize the types of denudation processes and land use change in space and time. Revised universal soil loss equation implemented in GIS environment was used to estimate the space–time pattern of soil loss and the soil erosion rates for each investigated year. The results showed that from 1955 to 2016, the study area was highly affected by denudation processes, mainly related to landslides and water erosion (slope wash erosion and gully erosion). Comparison of denudation processes maps showed that the total area affected by erosion processes has increased by about 31% and the distribution of geomorphic processes and their space–time evolution resulted from the complex interrelation between geoenvironmental features and human activities. The main land use changes concerned a decrease in areas covered by woodland, scrubland and pasture and an increase in croplands and barren lands that favored erosion processes. The most susceptible areas to soil loss in both years were mapped, and the mean soil loss rates for the study area were 6.33 Mg ha?1 y?1 in 1955 and 10.38 Mg ha?1 y?1 in 2016. Furthermore, the soil loss in 2016 has increased by about 64% compared to 1955. Finally, the results showed that integrating multi-temporal analysis of denudation processes, land use changes and soil loss rates might provide significant information on landscape evolution which supports decision makers in defining soil management and conservation practices.  相似文献   

12.
Assessment of soil suitability for sustainable intensive agriculture is an appropriate tool to select the land suitable for agricultural production with the least economic and environmental costs. This study was conducted to evaluate the agricultural soil quality in the northeast area of Tadla plain (Morocco) using geographic information system (GIS) and analytical hierarchy process (AHP). Six soil quality indicators, i.e., pH, organic carbon, cation exchange capacity, texture, salinity and slope were considered and performed in 60 subsurface soil samples. AHP method was utilized to identify the weight of each indicator from the pairwise comparison matrix. The weighted sum overlay analysis was then used to generate the soil quality map in a GIS environment, by overlaying both indicator weights and sub-indicator weights. The studied area was classified into four soil quality categories, i.e., poor, medium, good, and excellent, the percentage of each category is 1.12, 20.98, 61.07 and 16.83%, respectively. The results indicated that 1.12% of the study area has poor suitability for sustainable intensive agriculture due to their unsuitable texture and low salinity, while about 77% of cultivated soils are adapted to agricultural production. The above results could be useful for the management of agricultural activity.  相似文献   

13.
The investigated area is located south Egypt, between latitudes 22°00′N and 24°15′N, and longitudes 28°00′E and 30°00′E. It covers a total area of about 95,000.17 km2. The area was remotely sensed to identify landscape and its land and water resources. A reconnaissance survey followed by detailed one was done to verify the information resulted from satellite images. The prevailing deposits of the area could be expressed as (1) the Nubian sandstone, (2) the Quaternary sediments, and (3) the sand dunes belt. Fourteen main and sub-main landforms were recognized, i.e., sand sheets (high, moderately high, moderate, and low), depressions (high, moderately high, moderate, and low), dry valleys, peniplains, footslopes, barchans, tablelands, and scattered hills. Associated soils were distinguished and classified as Typic Torripsamments, Typic Haplocalcids, Typic Torrifluvents, and Typic Haplodurids. Spatial variability of soil and water characteristics was identified through using ordinary Kriging interpolation method. Land surface temperatures in both summer and winter seasons were derived from thermal band, and soil temperature regimes were defined digitally as hyperthermic. Water potentiality was identified and classified according to salinity and sodicity hazards to C2-S1 and C3-S1. Using GIS techniques, soil potentiality spatial model (SPSM) was designed to get potentiality classes, i.e., high, moderately high, moderate, low, and very low.  相似文献   

14.
The present work attempts to interpret the groundwater vulnerability of the Melaka State in peninsular Malaysia. The state of groundwater pollution in Melaka is a critical issue particularly in respect of the increasing population, and tourism industry as well as the agricultural, industrial and commercial development. Focusing on this issue, the study illustrates the groundwater vulnerability map for the Melaka State using the DRASTIC model together with remote sensing and geographic information system (GIS). The data which correspond to the seven parameters of the model were collected and converted into thematic maps by GIS. Seven thematic maps defining the depth to water level, net recharge, aquifer media, soil media, topography, impact of vadose zone and hydraulic conductivity were generated to develop the DRASTIC map. In addition, this map was integrated with a land use map for generating the risk map to assess the effect of land use activities on the groundwater vulnerability. Three types of vulnerability zones were assigned for both DRASTIC map and risk map, namely, high, moderate and low. The DRASTIC map illustrates that an area of 11.02 % is low vulnerability, 61.53 % moderate vulnerability and 23.45 % high vulnerability, whereas the risk map indicates that 14.40 % of the area is low vulnerability, 47.34 % moderate vulnerability and 38.26 % high vulnerability in the study area. The most vulnerability area exists around Melaka, Jasin and Alor Gajah cities of the Melaka State.  相似文献   

15.
The curve number (CN) is a hydrologic parameter used to describe the stormwater runoff potential for drainage areas, and it is a function of land use, soil type, and soil moisture. This study was conducted to estimate the potential runoff coefficient (PRC) using geographic information system (GIS) based on the area’s hydrologic soil group, land use, and slope and to determine the runoff volume. The soil map for the study area was developed using GPS data carried on to identify the soil texture to be used in building a soil hydrological groups map. Unsupervised and supervised classifications were done to Landsat 5/7 TM/ETM image to generate land-use and land-cover map. This map was reclassified into four main classes (forest, grass and shrub, cropland, and bare soil). Slope map for Al-Baha was generated from a 30-m digital elevation model. The GIS technique was used to combine the previous three maps into one map to generate PRC map. Annual runoff depth is derived based on the annual rainfall surplus and runoff coefficient per pixel using raster calculator tool in ArcGIS. An indication that in the absence of reliable ground measurements of rainfall product, it can satisfactorily be applied to estimate the spatial rainfall distribution based on values of R and R 2 (0.9998) obtained. Annual runoff generation from the study area ranged from 0 to 82 % of the total rainfall. Rainfall distribution in the study area shows the wise use of identifying suitable sites for rainwater harvesting, where most of the constructed dams are located in the higher rainfall areas.  相似文献   

16.
昭觉县是大凉山腹地的典型彝族聚居县,也是国家级深度贫困县,以传统农业居多,为推动农业发展方式的转变,昭觉县开展了现代农业园建设。笔者通过无人机航测,获取了拟建园区的高分辨率影像,使用面向对象的影像分析软件,快速提取了土地利用现状等信息,结合收集的其他资料,筛选了坡度、坡向、断层、地质灾害、土地利用、灌溉、交通、自然保护区8个评价因子,在GIS的支持下,先开展单因子土地适应性评价,然后进行综合评价。结果显示:拟建园区土地适宜性以适宜性高和适宜性较高等级为主,二者合计2.56 km2、占79.26%,超过3/4,土地适宜性好,适宜建设现代农业产业园,适合建设标准化蔬菜温室大棚和露地蔬菜种植基地,建成后,不但可以为周边地市提供蔬菜供应,还可带动园区周围农户增收,促进周围农户脱贫,发展前景好。小型无人机遥感系统具有机动灵活、成本低的优势,能快速获取小区域、大尺度农业产业园区的基础数据,在西南地区小区域土地适宜性评价中应用效果好。小区域土地的自然环境与社会环境相对单一,许多大区域土地适宜性评价指标并不完全适用,需要根据土地利用的主要目的选择合适的评价指标。  相似文献   

17.
An effective and efficient planning of an urban growth and land use changes and its impact on the environment requires information about growth trends and patterns amongst other important information. Over the years, many urban growth models have been developed and used in the developed countries for forecasting growth patterns. In the developing countries however, there exist a very few studies showing the application of these models and their performances. In this study two models such as cellular automata (CA) and the SLEUTH models are applied in a geographical information system (GIS) to simulate and predict the urban growth and land use change for the City of Sana’a (Yemen) for the period 2004–2020. GIS based maps were generated for the urban growth pattern of the city which was further analyzed using geo-statistical techniques. During the models calibration process, a total of 35 years of time series dataset such as historical topographical maps, aerial photographs and satellite imageries was used to identify the parameters that influenced the urban growth. The validation result showed an overall accuracy of 99.6 %; with the producer’s accuracy of 83.3 % and the user’s accuracy 83.6 %. The SLEUTH model used the best fit growth rule parameters during the calibration to forecasting future urban growth pattern and generated various probability maps in which the individual grid cells are urbanized assuming unique “urban growth signatures”. The models generated future urban growth pattern and land use changes from the period 2004–2020. Both models proved effective in forecasting growth pattern that will be useful in planning and decision making. In comparison, the CA model growth pattern showed high density development, in which growth edges were filled and clusters were merged together to form a compact built-up area wherein less agricultural lands were included. On the contrary, the SLEUTH model growth pattern showed more urban sprawl and low-density development that included substantial areas of agricultural lands.  相似文献   

18.
Estimating the potential direct runoff for urban watersheds is essential for flood risk mitigation and rainwater harvesting. Thus, this study aims to estimate the potential runoff depth based on the natural resources conservation service (NRCS) method and delineation of the watersheds in Riyadh, Saudi Arabia. To accomplish this objective, the geographic information systems (GIS) and remote sensing technique (RST) data were integrated to save time and improve analysis accuracy. The employed data include the digital elevation model (DEM), soil map, geology map, satellite images, and daily precipitation records. Accordingly, the hydrologic soil groups (HSG), the land use/land cover (LULC), and curve number (CN) were determined for each watershed in the study area. The results of this analysis show that the study area can be delineated into 40 watersheds with a total area of 8500 km2. Furthermore, the dominant HSG is group D, which represents about 71% of the total area. The LULC maps indicate four major land types in the entire study area: urban, barren land, agricultural land, and roads. The CN of the study area ranges from 64 to 98, while the weighted CN is 92 for the city. The rainfall-runoff analysis shows that the area has a high and very high daily runoff (35–50 and >?50 mm, respectively). Therefore, in this case, the runoff leads to flooding, especially in the urban area and agricultural lands.  相似文献   

19.
The geological environment has been heavily polluted by chemical substances over the past few decades. Pollution sources located on the earth’s surface or underground have affected the quality of the environment. A significant amount of impact could be reduced if the allocation of potential pollution sources was based on an evaluation of environmental conditions. The main objective of this study was to develop a methodology for the allocation of potential pollution sources by employing GIS and multi-criteria evaluation techniques. This methodology was applied to a study area located in the eastern part of Lithuania. A GIS-based land suitability analysis was performed after identifying 16 factors concerning the geological and socio-economic environment, which were important for environmental protection, land use and spatial planning. The environmental and socio-economic factors were divided into eliminating and limiting criteria. Criteria maps based on the selected factors were compiled. Areas delineated by eliminating criteria were identified as unsuitable for development (according to national legislation). Limiting criteria were evaluated according to the suitability level, which were determined in this study considering the principles of sustainable development. The relative importance of each criterion was assessed utilising the Analytical Hierarchy Process (AHP). A land suitability index (LSI) was calculated and the final result of the land suitability analysis was summarized in three suitability maps (environmental, socio-economic and composite). Four suitability classes (unsuitable, least, moderately and most suitable) for the allocation of potential pollution sources in the study area were used, and the nine most suitable candidate sites were selected according to the proposed methodology.  相似文献   

20.
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