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Geographical design of riparian buffers with long-term vegetation cover for environmental restoration in agricultural watersheds needs to assess how much farmland is located in the buffers of a concerned watershed. Traditionally, this assessment was done by field surveying and manual mapping, which was a time-consuming and costly process for a large region. In this paper, remote sensing (RS) and geographical information system (GIS) as cost-effective techniques were used to develop a catchments-based approach for identifying critical sites of agricultural riparian buffer restoration. The method was explained through a case study of watershed with 11 catchments and results showed that only four of the catchments were eligible in terms of higher priority for riparian buffer restoration. This research has methodological contributions to the spatial assessment of farming intensities in catchments-based riparian buffers across a watershed and to the geographical designs of variable buffering scenarios within catchments. The former makes the catchments-based management strategy possible, and the latter provides alternative restoration scenarios to meet different management purposes, both of which have direct implementations to the environmental restoration of riparian buffers in the real world. This study, thus, highlights the great potential of RS and GIS applications to the planning and management of riparian buffer restoration in agricultural watersheds. 相似文献
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Irrigation infrastructure development for smallholder farmers in developing countries increasingly gains attention in the light of domestic food security and poverty alleviation. However, these complex landscapes with small cultivated plots pose a challenge with regard to mapping and monitoring irrigated agriculture. This study presents an object-based approach to map irrigated agriculture in an area in the Central Rift Valley in Ethiopia using SPOT6 imagery. The study is a proof-of-concept that the use of shape, texture, neighbour and location information next to spectral information is beneficial for the classification of irrigated agriculture. The underlying assumption is that the application of irrigation has a positive effect on crop growth throughout the field, following the field's borders, which is detectable in an object-based approach. The type of agricultural system was also mapped, distinguishing smallholder farming and modern large-scale agriculture. Irrigated agriculture was mapped with an overall accuracy of 94% and a kappa coefficient of 0.85. Producer's and user's accuracies were on average 90.6% and 84.2% respectively. The distinction between smallholder farming and large-scale agriculture was identified with an overall accuracy of 95% and a kappa coefficient of 0.88. The classifications were performed at the field level, since the segmentation was able to adequately delineate individual fields. The additional use of object features proved essential for the identification of cropland plots, irrigation period and type of agricultural system. This method is independent of expert knowledge on crop phenology and absolute spectral values. The proposed method is useful for the assessment of spatio-temporal dynamics of irrigated (smallholder) agriculture in complex landscapes and yields a basis for land and water managers on agricultural water use. 相似文献
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Biplab Biswas 《Journal of the Indian Society of Remote Sensing》2009,37(4):705-717
Markov chains have been used to model spatial changes in a variety of spheres. Changes in social situations, economic standards,
natural resource availability, and even weather conditions have been explored and predicted using Markov Random Function (MRF)
and Markov Random Chains (MRC). In this section, we try to use data of Mahata village of Bhatar Block, extracted from GIS
based maps/images in a MRC to obtain present transition probabilities and predict future changes. The village is facing the
problem of decreasing the water table and at the same time the number of surface water bodies is also decreasing. This is
a serious situation for the development of the agricultural activities in general and at the same time it poses threat to
the human habitation of the village in the long run. The average depth of the ground water table from ground level increased
from 8 meter to 15 meter within the last 10 years. The threat is coming from the changes in land use and land cover, especially
due to substantial extension of agricultural activities which is expanding at a very fast rate. Increasing population is also
demanding more lands for settlement and industrial uses. The surface water bodies i.e. the ponds etc. are used for such intensive
irrigation purposes. As a result the surface water bodies depletes before the onset of summer. The cultivators use those dried
up ponds or surface water bodies for agricultural purposes also. There is thus a serious trend to convert the surface water
bodies into the agricultural land. It is estimated using MRC, that in next 25 years, the number of surface water bodies will
deplete by 50% in the agriculturally active Bhatar PS at the current rates of depletion. Shifting to less water needy crops,
prevention of LULC conversion, and water harvesting would provide some solace to the situation. 相似文献
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针对国家空间数据交换中心的安全性问题,通过一个实例从数据存储、数据库维护、动态网页技术（ＡＳＰ）进行了深入的研究和探讨,并进一步说明了ＡＳＰ技术在动态站点安全性维护中的诸多优势。 相似文献
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城市人口地理信息系统建设模式探讨 总被引：13，自引：1，他引：13
分析了国内外人口地理信息系统的发展概况，简述了目前我国建立城市人口地理信息系统的技术、数据基础和社会背景，初步提出一种建设城市人口地理信息系统的三层结构模式，以广州市的具体情况为例，探讨了人口地理信息系统建设过程中数据，数据库设计、人口数据仓库的建立、城市综合数据分析方法等关键问题。 相似文献
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Delineation of potential sites for water harvesting structures using remote sensing and GIS 总被引：6，自引：0，他引：6
M. Girish Kumar A. K. Agarwal Rameshwar Bali 《Journal of the Indian Society of Remote Sensing》2008,36(4):323-334
Availability of groundwater varies spatially and temporally depending upon the terrain. The scarcity of water affects the
environmental and developmental activities of an area. Construction of small water harvesting structures across streams/watersheds
is gaining momentum in recent years. In the present study, potential sites for construction of rainwater harvesting structures
in the Bakhar watershed of Mirzapur District, Uttar Pradesh, India have been identified by using remote sensing and GIS techniques.
Various thematic maps such as Landuse/Landcover, geomorphology and lineaments, etc. were prepared using remote sensing. These
layers along with geology and drainage were integrated using GIS techniques to derive suitable water harvesting sites. Each
theme was assigned a weightage depending on its influence on ground water recharge (for example weightages 20,18,15,25,25
and 0 were assigned to geomorphology, landuse, geology, lineament, drainage and road and villages respectively). Each class
or unit in the map was assigned a knowledge based ranking of one to four depending on its significance in storage and transmittance
of groundwater, and these values were multiplied with layer weightage to form score. The average score for excellent region
is greater than 200, for good 121 to 200, for moderate 81 to 121 and the other polygon having value less than 80 (excluding
zero) were assigned to poor category. The final map showing different categories of suitability sites for water harvesting
structures such as Check dams, Contour bunding, Recharge pits, Wells and Contour trenching have been suggested. 相似文献
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Niladri Gupta Md. Aktaruzzaman Chen Wang 《Journal of the Indian Society of Remote Sensing》2012,40(3):457-466
Eutrophication in lakes, estuaries and rivers occur due to over-enrichment with nutrients. Amongst the various nutrients Nitrogen (N) and Phosphorous (P) are the elements which are considered as the major pollutants. The present study looks into the problem of managing nutrient losses both from point sources and diffuse sources. The study was carried out in the River R?nne? catchment in South of Sweden where N and P have been assessed by creation of a pollution inventory based on GIS technology. The nutrient loads from different land use types were estimated using export coefficients and evaluated using monitoring data. A comparative analysis is done on the measured and estimated N and P leaching from diffused sources and point sources. Protective zones were suggested to decrease the P export from agricultural land, and the distribution of construction cost was analyzed among administrative regions according to the proportion of catchments, cultivated land, nutrient leaching, protective zone and length of river section within each municipality. The estimated error of the nutrient amount from landuse using GIS is 9.75% and 12.71% for N and P, respectively. The diffused sources contribute 91.53% and 94.74% of the total N and total P respectively, so the creation of a protective zone could be an effective way to decrease the nutrient export. The study demonstrates the power of GIS as a tool to analyze problems related to environmental monitoring and planning at administrative level, which could help in decision making and support for better management of the water resources. 相似文献
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Abstract Coastal Tropism is a worldwide phenomenon. It induces urgent needs for observation inventories and management of coastal environment, mainly in developing countries. High resolution satellite data may solve some aspects of the problems. Three examples based upon the potential use of shrimp aquaculture sites in tropical salt marshes, the biotopes mapping in coral reef environments for biologic stock assessments and the characterization and quantification of evolutive stages of coral platforms, are developed. All three are relative to the same tropical Pacific Island with respect, for the first and second examples, to actual needs for the management of mangroves and coral reefs and for the third, to a scientific approach related to evolutive theory of reefs platforms in lagoons. Methodology and results based upon digital image processing and computer assisted photointerpretation are exposed. New trends in digital processing and associated digital cartography are listed. 相似文献
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One of the prime global issues in the field of hydrological science is water scarcity and its degrading quality. In this paper, geographic information system (GIS) and remote sensing techniques are applied over a study of granite watershed area of ～200 km2 with semi-arid climatic conditions for estimating surface runoff using a modified soil conservation service curve number method and subsequent site selection for water harvesting structures such as check dams and percolation ponds to enhance recharge of groundwater. Further, some of the sites selected for appropriate construction of recharge structures through analytic hierarchy process were investigated for site efficacy. All the recharge sites selected were found feasible and appropriately suitable. This study demonstrates the capability of GIS and its application for the construction of water harvesting structures over semi-arid areas. 相似文献
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Seyed Ali Jozi Farkhondeh Ebadzadeh 《Journal of the Indian Society of Remote Sensing》2014,42(2):363-371
The present study was carried out to evaluate agricultural capability of a watershed located in Khuzestan; a province in southern Iran. It is aimed to examine the applicability of Multi Criteria Decision-Making (MCDM) methods in site selection process. Accordingly, the ecological resources of the watershed were initially identified. To specify the criteria required for agricultural land evaluation, Delphi method was applied. After selecting the criteria, they were weighted using Analytical Hierarchy Process (AHP) Method. Weighted Overlay (WO) Method was also used to overlay the map layers in the GIS environment. Afterwards, sensitivity analysis was performed using Weights Sensitivity Analysis (WSA) method to show the impressibility rate of the results against a certain changes in the inputs. The results revealed that out of 6591.2 ha of the total watershed area, 50.8 % has unsuitable potentiality while 27.32 % has a poor suitability for irrigated agriculture. It was also determined that only 6.96 % of the whole study area has a suitable potential for this purpose. Besides, the findings indicated that 23.38 % of the total watershed area is unsuitable for rain-fed farming. the results also showed that 31.78 % and 19.12 % of the entire study area has moderate and high potentials for rain-fed agriculture, respectively. In a general overview, this study could present how MCDM is effective in handling land capability studies. 相似文献
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Attitude determination by integration of MEMS inertial sensors and GPS for autonomous agriculture applications 总被引：3，自引：3，他引：3
Integration of Global Positioning System (GPS) and Inertial Navigation System (INS) technologies, which has widespread usage
in industry, is also regarded as an ideal solution for automated agriculture because it fulfils the accuracy, reliability
and availability requirements of industrial and agricultural applications. Agriculture applications use position, velocity
and heading information for automated vehicle guidance and control to enhance the yield and quality of the crop, and in order
to vary the application of fertilizer and herbicides according to soil heterogeneity at sub-field level. A loosely coupled
GPS/INS integration algorithm known as “AhrsKf” is introduced for automated agriculture vehicle guidance and control utilizing
MEMS inertial sensors and GPS. The AhrsKf can produce high-frequency attitude solutions for the vehicle’s guidance and control
system, by using inputs from a single survey grade L1/L2 antenna, eliminating the need for the previous two antenna solutions.
Given its agricultural application, the AhrsKf has been implemented with some specific design features to improve the accuracy
of the attitude solution including, temperature compensation of the inertial sensors, and the aid of plough lines of farm
lands. To evaluate the AhrsKf solution, two benchmarking tests have been conducted by using a three-antenna GPS system and
NovAtel’s SPAN-CPT. The results have demonstrated that the AhrsKf solution is stable and can correctly track the movement
of the farming vehicle. 相似文献
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ABSTRACT Globally, countries have experienced substantial increases in farmland abandonment. Although vegetation phenology is a key factor for the classification of land use, understanding of the phenological change of abandoned farmland is lacking. Using harmonic analysis of NDVI and NDWI extracted from Landsat imagery, this study investigates the distinctive phenological characteristics of abandoned farmland, which contrasts with that of three other agricultural types (paddy, agricultural field, orchard) in the study site of Gwangyang City in Jeollanam Province, South Korea. The results suggest that abandoned farmland has higher overall greenness coverage and overall water content in vegetation than the other uses. In terms of both indices, abandoned farmlands changed with relatively less fluctuation than those of other uses, suggesting the existence of constant and unmanaged vegetation from ecological succession, which differs from crop fields that undergo cultivation procedures. The significant harmonic components differed among agricultural types and vegetation indices. In paddy, NDVI was explained with multiple, higher-order harmonic components, while in other types only first-order components met the 5% statistical significance level. With NDWI, land types were more clearly discernible, because of the different cultivation procedures involving water: wet-field method (paddy), dryland farming (orchard, agricultural field), and no cultivation (abandoned farmland). The analysis confirms that harmonic analysis could be useful in discerning abandoned farmland among areas of active agricultural use and shows that the statistical significance of harmonic terms can be employed as indicators of different agricultural types. The observed pattern of the geographic distribution of abandoned farmland has policy implications for the promotion of sustainable reuse of marginal farmland. 相似文献
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A. Geetha Selvarani G. Maheswaran K. Elangovan 《Journal of the Indian Society of Remote Sensing》2017,45(1):67-77
The water is a nature’s valuable gift to all life forms. Water quality and quantity plays a major role for the growth and development of community. Both natural and human factors influence the quality and quantity of water source. Depending upon the quality and quantity of groundwater it can be used for various purposes, such as drinking, agricultural and industrial. Due to revolution in industries and various anthropogenic sources in the past decades, groundwater has been polluted and depleted. Remote sensing and Geographical Information System (GIS) has become one of the leading tools in the field of hydrogeological science, which helps in assessing, monitoring and conserving groundwater resources. GIS technology provides suitable alternatives for efficient management of large and complex databases. In recent years, the increasing use of satellite remote sensing data has made it easier to define the spatial distribution of different groundwater prospect classes on the basis of geomorphology and other associated parameters. Analysis of remotely sensed data along with Survey of India(SOI) topographical sheets and collateral information with necessary field checks helps in generating the base line information for artificial recharge. The artificial recharge sites were identified by integrating thematic maps of geology, geomorphology, slope, drainage density and lineament density of the study area. The study focuses on the development of remote sensing and GIS based analysis and methodology for identifying artificial recharge studies in Noyyal river basin. 相似文献
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K. Nageswara Rao G. Murali Krishna D. Ramprasad Naik B. Hema Malini 《Journal of the Indian Society of Remote Sensing》2003,31(2):71-80
Interpretation of IRS LISS II and LISS III imagery has revealed the various landforms as well as land use/land cover features in a part of the Godavari delta coastal belt. A comparative analysis of geomorphological vs. land use/land cover maps suggested that the landforms exert a certain degree of control over human land use activities even in this monotonously plain area. Further, an analysis of the sequential imagery pertaining to 1992 and 2001 aimed at detecting the land use/land cover change has indicated that the aquaculture has phenomenally increased by 9,293.5 ha during the 9-year period. At the same time, the cropland which occupied about 29,104 ha in 1992 has been reduced to 19,153.9 ha by 2001 mainly due to the encroachment of aquaculture. Village level data on temporal variation in land use/land cover extracted through GIS analysis revealed that in 14 out of the total 39 villages in the area, the conversion of cropland into aquaculture ponds was more than 30% with the highest conversion rate of 89.8% in Gondi village. These fourteen villages, which are designated as ‘aquaculture hotspots’ are grouped into 4 priority classes based on the intensity of conversion. 相似文献
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GIS Methodology for Characterizing Historical Conditions of the Willamette River Flood Plain, Oregon
Doug R Oetter Linda R Ashkenas Stanley V Gregory Paula J Minear 《Transactions in GIS》2004,8(3):367-383
Recent environmental developments have stimulated an interest in conservation and restoration of the historical Willamette River flood plain, both to protect against flooding and to provide wildlife habitat. In order to best utilize scarce resources, we characterized historical and modern river channel and flood‐plain conditions to evaluate changes and help prioritize restoration sites. Using cartographic and photographic data sources, we developed a Geographic Information System (GIS) to map active channels, side channels, islands and tributaries for four separate dates, as well as riparian and flood‐plain vegetation characteristics for pre‐European settlement and modern time periods. Coverages based on flood records and other boundaries were used to partition the flood plain into spatial subsets for analysis. The GIS allowed comparisons between historical and present conditions for a variety of environmental factors. Much of the pre‐settlement channel complexity has been removed. Total channel length in 1995 was 26% less than in 1850, with almost 58% of the river's side channels disconnected from the system. In addition, we found a 72% loss of flood‐plain forest from 1850 to 1995, since it was converted to agricultural and urban land uses. Selected river and flood‐plain variables were made available for a spatial model to prioritize potential locations for flood‐plain restoration. 相似文献