Integrative approach of RS and GIS in characterization of land suitability for agriculture: a case study of Darna catchment

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.     

Land suitability assessment for sugarcane cultivation in Bijnor district,India using geographic information system and fuzzy analytical hierarchy process

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.     

Land suitability decision support for assessing land use changes in areas west of Nile Delta,Egypt

The main objective of this study was to discuss the efficiency of agricultural land suitability for assessing land use types in rural areas. In this research, El-Nubariya area west of Nile Delta was selected as a case study site, which considers one of the high priority regions for future development in Egypt. As input, a total of ten representative soil profiles and number of observations points were used for collecting soil samples. Based on the field survey, laboratory analysis, and satellite image interpretation in cooperation with geographic information system (GIS), the physiographic map was executed. Three main landscape units were identified as follow: marine deposits, eolian deposits, and river terraces. The soils were classified mainly as Typic Torripsamments, Typic Paleorthids, and Typic Calciorthids. Land suitability assessment was done to define maps of the suitable areas for agricultural production using MicroLEIS microcomputer program and ALESarid-GIS system as well. According to the crop suitability results, the most suitable crops to grow in the study area were maize, melon, potato, sunflower, onion, garlic, olive, and date palm in the order indicated. Generally, the data on land suitability resulting from the evaluation models indicated that 56.1 % of the area is considered as suitable, 30.8 % is moderately to marginally suitable, and 13.1 % is not suitable. The main limitation factors for land suitability are the excess of salts, shallow soil depth, and inadequate drainage conditions. The output results are presented as georeferenced soil suitability maps using GIS utilities.     

基于GIS的牡丹江市主城区建设用地适宜性评价

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.     

吉林西部大安灌区土壤贮水能力空间变异特征及土壤水分有效性

为研究吉林西部土壤贮水能力的空间分布特征和水分有效性,以吉林西部大安灌区为研究对象,通过试验测定土壤贮水量及根系区土壤的水分特征曲线,并利用van Genuchten模型进行水分特征曲线拟合,结合经典统计和地统计分析方法分析土壤贮水量空间变异特征。结果表明:盐碱土和非盐碱土吸持贮水量、滞留贮水量和饱和贮水量的均值之间不存在显著性差异(P0.05),实际贮水量均值存在显著差异(P0.05);土壤实际贮水量呈现由西向东、由北向南逐渐升高的变化趋势,且南北方向的空间变异性均高于东西方向的空间变异性;轻度盐碱地、水田和旱田实际有效含水量分别占其最大有效含水量的78.94%、58.28%和56.62%,水分有效性较高,蔬菜地、高粱地、草甸土以及中度和重度盐碱土实际有效含水量占其最大有效含水量的20.83%27.13%,土壤水分有效性较小;水田、轻度和中度盐碱地的贮水和持水能力强,旱田和蔬菜地土壤贮水能力较强,持水能力中等,而重度盐碱地、高粱地、草甸土等土壤的持贮水能力较弱。研究结果对旱改水工程水资源管理和预防次生盐渍化有重要意义。     

A GIS-index integration approach to groundwater suitability zoning for irrigation purposes

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.     

Use of satellite data and GIS for assessing the agricultural potentiality of the soils South Farafra Oasis, Western Desert, Egypt

Overpopulation and food security are the main global problems alert decision makers. In developing countries, such problem put extra pressure for horizontal expansion for agricultural development. The rapid sprawl of urbanized areas on the alluvial land of the River Nile and delta to accommodate the population growth has encouraged governmental and private sector for agricultural expansion in the desert. Unless there are reliable information and accurate studies for land and soil suitability, there will be a collapse of such investment. To evaluate the potential suitability of soil for agriculture development in areas of the western desert, satellite images, geographic information, and field survey including soil profiles and artesian water samples with laboratory analysis were integrated to classify the soils according their suitability for specific crop. The main land qualities of the different mapping units and the crop requirement were rated and matched to obtain the current and potential land suitability using Automated Land Evaluation System “ALES”. The study found that the main physiographic units are plateaus, hilland, mountain, and depression floor. But there are three limiting parameters for land suitability which are the lack of nutrient elements, wind erosion vulnerability, and soil texture. The study concluded that the best crops adapted with the soil conditions and could be feasible for economic use are: (1) native vegetation such as agol, sand trees, sammar, halfaa, bawaal, qordaob, bardi, and qortom; (2) filed crops such as onion, garlic, watermelon and wheat; and (3) fruits such as olive and date palms.     

Assessment of land degradation east of the Nile Delta, Egypt using remote sensing and GIS techniques

Land degradation is one of the most common issues in the eastern part of the Nile Delta area that threatens the ongoing agricultural activities and prohibits further reclamation expansions. The different degradation types and the associated risk assessment of some soils types of western Suez Canal region during the period from 1997 to 2010 is discussed. The assessment of the different degradation degrees in the investigated area has been carried out through integrating remote sensing, GIS and GLASOD approaches. Results revealed that the salinization, alkalization, soil compaction and water logging are the main types of land degradation in the area. The main causative factors of human induced land degradation types are; over irrigation, human intervention in natural drainage, improper time use of heavy machinery and the absence of conservation measurements. Low and moderately clay flats, gypsifferous flats, have high to very high risk in both salinization sodication and physical degradation. Values such as EC, ESP, and ground water level reach 104.0 dS/m, 176? % and 60 cm, respectively. These results will be of great help and be basic sources for the planners and decision makers in sustainable planning. The spatial land degradation model was developed based on integration between remote sensing data, geographic information system, soil characteristics and DEM.     

Hydrogeological conditions and aquifers potentiality for sustainable development of the desert areas in Wadi Qena,Eastern Desert,Egypt

To increase the potentiality of development and land reclamation activities, the Egyptian government funds the construction of a new desert road in Upper Egypt. This road connects Upper Egypt with the Red Sea Governorate. Surrounding the road is 207,000 acres of land surface which is almost flat and suitable for reclamation. To ensure the sustainability of the proposed development surrounding the road, analyses of the morphometric parameters, infiltration test and the grain size distribution, geoelectrical and hydrogeological investigations were conducted in the area. The results indicated a possibility of flash flood hazards and poor drainage condition for land reclamation activities is expected. The hydrogeological and geoelectrical investigations revealed that the unconfined Quaternary and confined Nubian Sandstone aquifers are the main aquifers in the area. The depths to water in the two aquifers range from 18 to 36 and 80 to 300 m with an average thickness of 40 and 275 m, respectively. The aquifers are made of sands and silt with clay intercalations. The total dissolved solids of water ranges between 1,700 and 5,400 mg/L, whereas the sodium absorption ratio ranges between 7 and 30 meq/L, indicating the suitability of water for irrigating medium- to high-salt-tolerant crops with proper drainage facilities. Thus, water in this area is not suitable for domestic use. Based on hydrogeological equations, the available water for extraction from the aquifers in the area is about 17.195?×?10⁹ m³, and this volume is not feasible to reclaim the whole proposed area for reclamation. Meanwhile, it may be possible to water small farms (not more than 60,000 acres for 50 years). Surface water source should be considered for the sustainability development of the area.     

GIS-based land suitability analysis integrating multi-criteria evaluation for the allocation of potential pollution sources

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.     

基于GIS的岩溶煤矿区土地利用适宜性评价研究——以重庆市南桐矿区为例

以SPOT5卫星为基本信息获取该地区的地貌数据,并根据该地区的土地利用现状、土壤特征、煤炭开采状况等9个指标,采用多因素分级指标综合评价法对南桐矿区的土地利用适宜性进行评价。按照土地的用途划分宜耕、宜园和宜林土地类三个类型,根据影响因子对土地用途的影响程度制定分级指标。评价结果表明,高度适宜、中等适宜、基本适宜和不适宜耕地分别为5 321hm2、8361hm2、7 973hm2和4 656hm2;园地分别为315hm2、629hm2、405hm2 和117hm2;林地分别为8 867hm2、7303hm2、5 977hm2 和2 643hm2。为能更好地利用土地资源和促进矿区的可持续发展,建议将原来的耕地、园地和林业用地比例10∶ 0. 6∶ 9. 4调整为10∶ 5. 7∶ 14。      

GIS-based multi-criteria land suitability analysis for sustainable agriculture in the northeast area of Tadla plain (Morocco)

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.     

Groundwater quality suitable zones identification: application of GIS,Chittoor area,Andhra Pradesh,India

Due to uneven spatial and temporal distribution of rainfall and lack of sufficient water management technologies, the development activities of the society are totally depending on groundwater resources. In addition to the prevailing drought-prone conditions, the improperly treated and unplanned release of effluents of industry, municipal and domestic into the nearby streams and ponds and the majority usage of groundwater for irrigation are increasing the ionic concentration of the groundwater and making it more saline. The analytical results of the collected groundwater samples show that the groundwater is alkaline, and sodium and bicarbonate are the dominant cation and anion, respectively. Gibbs variation diagram shows that the control of the chemistry of groundwater in the study area is the weathering of granitic gneisses and also the leaching of evaporated and crystallized ions from the topsoil of the irrigated areas and improperly treated industrial effluent ponds. GIS, a potential tool for facilitating the generation and use of thematic information, has been applied and analyzed for identification of groundwater quality suitable zones for domestic and irrigation purposes. 30.06% of the area is with suitable, 67.45% of the area is with moderately suitable and 2.45% of the area is with unsuitable quality of groundwater for domestic purpose. 46% of the area is with suitable, 53.36% of the area is with moderately suitable and 0.64% of the area is with unsuitable quality of groundwater for irrigation purpose.     

Identification of suitable sites for groundwater recharge in Awaspi watershed using GIS and remote sensing techniques

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.     

基于大数据的上海市人居环境适宜性评价

人居环境是居民生活和社会发展的重要基础,科学量化人居环境适宜性有助于引导区域人口规划,促进人口与资源协调发展。本文基于大数据,运用GIS技术,从居住环境、社会环境、经济环境和生态环境四个方面构建综合评价指标体系,以1 km栅格为基本单元,对上海市人居环境适宜性进行空间测度评价。结果表明:上海市人居环境指数介于-1.79~45.57之间,空间分布上呈现中心城区向周边区域递减的态势,整体分布趋势与人口密度相关性较高。高值区主要集中在中心城区一带,土地面积较小,人口密度大,承载压力较大;发展潜力较高的中等适宜区主要涉及外环及新城区域,土地面积大,是未来人口导向的潜力区。     

内蒙古河套灌区浅层地下水化学特征和灌溉适宜性分析

随着黄河流域水资源供需矛盾加剧,我国特大型灌区——内蒙古河套灌区开始采用黄河水与地下水相结合的方式进行农业灌溉。本研究采集河套灌区内499组地下水样品和1组黄河水样品,在分析地下水和黄河水样品的水化学特征基础上,运用钠吸附比(SAR)、渗透指数(PI)、钠含量(SC)和残余碳酸钠(RSC)以及《农田灌溉水质标准(GB 5084—2021)》对地下水和黄河水的灌溉适宜性进行对比分析。结果表明,地下水与黄河水均为弱碱性水,Ca²⁺和HC0₃^-为优势离子,Gibbs图显示地下水受到岩石风化淋溶和蒸发浓缩的双重影响,对灌溉适宜性影响较大的钠盐主要来自岩盐溶解。灌溉适宜性分析结果表明,从SAR、PI和RSC指标来看,地下水的灌溉适宜性较好,从SC指标来看,不适宜灌溉的地下水主要分布在灌区北部总排干和灌区南部黄河沿岸;根据农田灌溉水质标准分析,除总砷和氯化物两项指标外,其余指标适宜灌溉样品占比均高于90%,综合评价全区共231组地下水样品适宜灌溉。地下水与黄河水灌溉适宜性对比表明,黄河水的SAR和SC指标灌溉适宜性分析结果较好,地下水的PI和RSC指标灌溉适宜性分析结果较好,根据灌溉水质标准显示黄河水所有指标均适宜灌溉。本研究为日后内蒙古河套灌区合理选用灌溉水源提供数据支撑,为该区域地下水的治理与防控提供科学依据。     

A GIS model for settlement suitability regarding disaster mitigation, a case study in Bolu Turkey

A GIS (Geographic Information Systems) model was developed for Bolu Province in Turkey primarily for earthquake disaster mitigation purposes. The model served as the basis for investigating earthquake disaster vulnerability of existing settlements and identifying areas for new settlements in the Bolu Provincial Center and its counties. The set of criteria investigated in the GIS model was the following: distance from the main fault, ground acceleration, geologic basement type and terrain slope. Based on these criteria, a settlement suitability map was created, which classified the province into low, medium and high settlement suitable areas. This map was then augmented with other criteria for refinement purposes. These included the land use capability classes map of the province, the contemporary land use map derived from satellite images and the historical and contemporary earthquake occurrences within the region. Finally, the road network of the province derived from satellite images was overlaid on the settlement suitability map so that the provincial administrators could leave an evacuation zone of 200 m around the roads. This settlement suitability map is also intended to assist provincial administrators in making plans for reinforcement of existing settlements in low settlement suitable regions and opening new areas for urbanization and industrialization in high settlement suitable regions.