On the basis of data from Soil Test and Formula Fertilization project in Qimen county,we employed Geographic Information System Software ArcGIS 9.2 and CLRMIS(Cultivated Land Resource Management Information System at...On the basis of data from Soil Test and Formula Fertilization project in Qimen county,we employed Geographic Information System Software ArcGIS 9.2 and CLRMIS(Cultivated Land Resource Management Information System at County Scale) to establish region-specific estimation index system for tea cultivation in Qimen County by determining the estimation units,and carried out quantitative estimation analysis on tea cultivation there via comprehensive evaluation indices for natural elements of cultivated land.The results showed that the highly suitable,suitable,reluctantly suitable and unsuitable acreages are 5 665.8,8 327.1,8 415.9 and 11 979.9 hm2 respectively,accounting for 24.0%,35.3%,35.7% and 5.1% of the total acreage of cultivated land.These results would facilitate the production of high yield and quality tea in Qimen County.展开更多
[Objective] This study was to evaluate the ecological suitability of agricultural land in western Jilin Province, with the aim to provide basis for the effective application of agricultural resources and the structura...[Objective] This study was to evaluate the ecological suitability of agricultural land in western Jilin Province, with the aim to provide basis for the effective application of agricultural resources and the structural adjustment of land use. [Method] The evaluation index system was constructed based on fuzzy mathematic method according to the principles of systematic, dominant, effectiveness and feasibility; based on law of tolerance, reasonable evaluation criteria were determined according to the ecological amplitude of crops; based on GIS processing, the initial data completed the mathematical operation by using the VBA program in Excel. [Result] The area of agricultural land grade I was 5 512 km2, grade II of 25 985 km2, grade Ill of 7 907 km2, and area of land not suitable for agriculture was 6 312 km2. According to the evaluation results, the key areas for land use adjustment were Zhenlai County, Da'an County, Tongyu County and western Changling County. The directions of land use adjustment included improving irrigation and drainage conditions, governing land salinization and conversion of cropland to forest and grassland. [Conclusion] This study provided basis for the effective application of agricultural resources and ecological environment construction in western Jilin Province.展开更多
According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat ...According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat area. Then this study deter- mined single evaluation factors index and comprehensive suitability index using "ex- treme conditions method" and "suitability index method", and analyzed and assessed the constructive land suitability on each evaluation unit polygons and its suitability level by using GIS software. Taking Lianghe County of Dehong Dai-Jingpo Au- tonomous Prefecture as an example to evaluate land suitability in Lianghe County's main towns around the gentle slope, the results show, in the evaluation area, the area of land suitable for construction and unsuitable for construction respectively ac- count 73.58% and 26.42%. And first-class, second and third-class of land suitable for construction should be composited at the ratio of about 11:49:40. The suitability evaluation index system and method developed in this paper is applicable for evalu- ating the construction land suitability in mountainous areas of southwest Yunnan Province, and will provide theoretical and technical support for land policy measures which strengthen the protection of farmland and promote the scientific development of urbanization in Yunnan Province and even similar mountainous areas of the whole China.展开更多
Basing on the limiting factor method and Composite Index method,for the northern China crop-pasture band,the authors established the system of evaluation index,and abstracted the dominant factor,then through applying ...Basing on the limiting factor method and Composite Index method,for the northern China crop-pasture band,the authors established the system of evaluation index,and abstracted the dominant factor,then through applying expert grade and weighing way the suitability of grids are evaluated,the results showed that:without the input of a large number of cash,most of the area was not suitable for farming,and more appropriate area for farming was only 8.45% of total area,mainly located in the southeast and southwest of the study area,followed by the study area in the northeast,areas that was not suitable for farming mainly in the middle of the east,large areas of central and western regions.展开更多
[Objective] This study aimed to analyze the sustainability of cropland use in cropping-pastoral ecotone before and after the Grain-for-Green Policy. [Method] Using Yanchi County in Ningxia Hui Autonomous Region as a c...[Objective] This study aimed to analyze the sustainability of cropland use in cropping-pastoral ecotone before and after the Grain-for-Green Policy. [Method] Using Yanchi County in Ningxia Hui Autonomous Region as a case study area, this investigation used the annual transfer rate of land use types, cropland suitability and emergy analysis to examine the major pressures affecting the sustainable use of cropland before and after the Grain-for-Green Policy. [Result] The expansion of con- struction land onto cropland was significant; the annual cropland area was still larger than the land area suitable for cropping after the policy; agrochemical inputs used for crop production gradually increased and unit crop outputs required more agro- chemical inputs. Cropland use sustainability showed a fluctuating downward trend. [Conclusion] The results imply that the protection of high quality cropland, further im- plementation of the policy and control of agrochemical inputs according to precipita- tion are the main measures needed for sustainable cropland use in cropping-pastoral ecotone.展开更多
Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana,...Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana, P. ( eurameri cana and P. simonii, which were planted in loess hilly land in northwest Shanxi Province, were tested under different planting densities and site conditions. A randomized block design and three times repetition were adopted in the test. Bas ed on the test results in arid and cold area of the northwest Shanxi, the hybrid poplar trees taking Populus cathaysna as their female parent could be selected for afforestation, such as P. popularis and P. opera, and the growing space of s ingle plant should be larger than 20 m2. P. bolleana as an introduced tree speci es grows well in this area, but its growth is likely affected by ground water co ndition. On the site with relatively abundant soil water, P. bolleana usually su ffer from frost crack at its trunk base. As a result, P. bolleara is suited to p lanting in the site where is short of soil water. P. x euramericana is not suita ble for large-scale afforestation, especially in arid slopes and ridges of loess hilly land .展开更多
In the view of new rural living environment,problems existing in the construction of current new rural living environment were analyzed so as to propose some theoretical ideas and ways for resolving the problems exist...In the view of new rural living environment,problems existing in the construction of current new rural living environment were analyzed so as to propose some theoretical ideas and ways for resolving the problems existing in the design of new rural living environment.展开更多
The paper aims to study agricultural land suitability in typical agricultural area in Huanghuaihai plain by the comprehensive evaluation of natural factors and environmental conditions of agricultural land with Liaoch...The paper aims to study agricultural land suitability in typical agricultural area in Huanghuaihai plain by the comprehensive evaluation of natural factors and environmental conditions of agricultural land with Liaocheng area in Shangdong Province in the center of Huanghuaihai plain as a case.The results suggested that the land quality in Liaocheng was above the average and accorded with the local practical situation.The authors validated the scientificity of agricultural land suitability study by using GIS technology and proposed some suggestions on analysis results.展开更多
The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aimin...The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aiming at this limitation,an ecological suitability evaluation analysis model was presented based on fuzzy theory and a research on urban growth boundary(UGB) of the Great-Hexi Leading District(GHLD) of Changsha was conducted.With the support of GIS,RS and MATLAB,slope,elevation,vegetation,soil productivity,soil permeability,water body and land use are selected as the input of model according to the characteristic properties of soil and terrain in red soil hilly areas.The running result of this model indicates that the ratios of highly suitable land,suitable land,moderately suitable land and unsuitable land in GHLD are 18.75%,10.31%,64.16%,6.78%,respectively.This result accords with spatial structure worked out by Space Development Strategy Planning of GHLD,Based on this result,several suggestions are made to guide UGB developments in future.展开更多
A GIS-based method was used to assess land suitability in the Qinling Mountains, Shaanxi Province of China through simultaneous consideration of physical features and current land use. Through interpretation of Landsa...A GIS-based method was used to assess land suitability in the Qinling Mountains, Shaanxi Province of China through simultaneous consideration of physical features and current land use. Through interpretation of Landsat TM images and extensive field visits the area was modeled into 40 land types in five altitudinal zones (valleys and gullies, hillsides and terraces, foothills, mid-mountain, and sub-alpine mountain). Then, a suitability score was assigned to five physical factors (climate, hydrology, topography, soil, and vegetation). Next, their integrated overall suitability value scores were compared with the observed land cover to determine whether it should be reallocated a new use. Results showed that the five suitability classes of agriculture, forest, grassland, farmland-woodland, and scrub-pasture had altitudinal stratification and a total of 1151 km2 (8.89%) of lands on the northern slopes of the Qinling Mountains had to be reallocated. To achieve this reallocation, 657 km2 of arable land should be reduced, and forest, grassland and scrub-pasture increased by 615 km2, 131 km2 and 405 km2, respectively. Implementation of these recommended land reallocations should help achieve suitable use of land resources and prevent land degradation.展开更多
The eastern fall cohort of the neon flying squid, Ommastrephes bartramii, has been commercially exploited by the Chinese squid jigging fleet in the central North Pacific Ocean since the late 1990s. To understand and i...The eastern fall cohort of the neon flying squid, Ommastrephes bartramii, has been commercially exploited by the Chinese squid jigging fleet in the central North Pacific Ocean since the late 1990s. To understand and identify their optimal habitat, we have developed a habitat suitability index (HSI) model using two potential important environmental variables -- sea surface temperature (SST) and sea surface height anomaly (SSHA) -- and fishery data from the main fishing ground (165°-180°E) during June and July of 1999-2003. A geometric mean model (GMM), minimum model (MM) and arithmetic weighted model (AWM) with different weights were compared and the best HSI model was selected using Akaike's information criterion (AIC). The performance of the developed HSI model was evaluated using fishery data for 2004. This study suggests that the highest catch per unit effort (CPUE) and fishing effort are closely related to SST and SSHA. The best SST- and SSHA-based suitability index (SI) regression models were SISST-based = 0.7SIeffort-SST + 0.3 SICPUE-SST, and SISSHA-based =0.5Sleffort-SSHA + 0.5SICPUE-SSHA, respectively, showing that fishing effort is more important than CPUE in the estimation of SI. The best HSI model was the AWM, defined as HSI=0.3SISSHA-based+ 0.7SISSHA-based, indicating that SSHA is more important than SST in estimating the HSI of squid. In 2004, monthly HSI values greater than 0.6 coincided with the distribution of productive fishing ground and high CPUE in June and July, suggesting that the models perform well. The proposed model provides an important tool in our efforts to develop forecasting capacity of squid spatial dynamics.展开更多
Camellia sinensis is an important commercial crop in China. Suitability evaluation of tea tree planting, which is an embodiment of agricultural planting based on Geographic Information System(GIS), includes overlay ...Camellia sinensis is an important commercial crop in China. Suitability evaluation of tea tree planting, which is an embodiment of agricultural planting based on Geographic Information System(GIS), includes overlay analysis, hierarchical analysis,artificial intellegence, multivariable linear regression and fuzzy evaluation. Via a series of functions of GIS such as data query, retrieve and management, we can be informed of current situation and problems in tea plant development, find out areas which are appropriate or inappropriate for Camellia sinensis planting and figure out corresponding planting schemes and policies. Science and technology are the basic solution to modernization of Camellia sinensis planting. It is necessary to set up decision information and plantation management systems in agriculture on account of GIS, which are important channels to regionalization of Camellia sinensis planting suitability.展开更多
In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal par...In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal parameters and three-dimensional(3 D)body-wave high-resolution velocity structures at depths of 0–30 km were retrieved by double-difference tomography.Results show that there is a good correspondence between the spatial distribution of the relocated earthquakes and velocity structures,which were concentrated mainly in the high-velocity-anomaly region or edge of high-velocity region.Velocity structure of P-and S-waves in the Yibin area clearly shows lateral inhomogeneity.The distribution characteristics of the P-and S-waves near the surface are closely related to the geomorphology and geologic structure.The low-velocity anomaly appears at the depth of 15–25 km,which is affected by the lower crust current.The Junlian–Gongxian and Gongxian–Changning earthquake areas,which are the two most earthquake-prone areas in the Yibin region,clearly differ in earthquake distribution and tectonic characteristics.We analyzed the structural characteristics of the Junlian–Gongxian and Gongxian–Changning earthquake areas on the basis of the 3 D bodywave velocity structures in the Yibin region.We found that although most seismicity in the Yibin area is caused by fluid injection,the spatial position of seismicity is controlled by the velocity structures of the middle and upper crust and local geologic structure.Fine-scale 3 D velocity structures in the Yibin area provide important local reference information for further understanding the crustal medium,seismogenic structure,and seismicity.展开更多
Land suitability assessment is a prerequisite phase in land use planning; it guides toward optimal land use by providing information on the opportunities and constraints involved in the use of a given land area. A geo...Land suitability assessment is a prerequisite phase in land use planning; it guides toward optimal land use by providing information on the opportunities and constraints involved in the use of a given land area. A geographic information system-based procedure, known as rural settlement suitability evaluation(RSSE) using an improved technique for order preference by similarity to ideal solution(TOPSIS), was adopted to determine the most suitable area for constructing rural settlements in different geographical locations. Given the distribution and independence of rural settlements, a distinctive evaluation criteria system that differed from that of urban suitability was established by considering the level of rural infrastructure services as well as living and working conditions. The unpredictable mutual interference among evaluation factors has been found in practical works. An improved TOPSIS using Mahalanobis distance was applied to solve the unpredictable correlation among the criteria in a suitability evaluation. Uncertainty and sensitivity analyses obtained via Monte Carlo simulation were performed to examine the robustness of the model. Daye, a resource-based city with rapid economic development, unsatisfied rural development, and geological environmental problems caused by mining, was used as a case study. Results indicate the following findings: 1) The RSSE model using the improved TOPSIS can assess the suitability of rural settlements, and the suitability maps generated using the improved TOPSIS have higher information density than those generated using traditional TOPSIS. The robustness of the model is improved, and the uncertainty is reduced in the suitability results. 2) Highly suitable land is mainly distributed in the northeast of the study area, and the majority of which is cultivated land, thereby leading to tremendous pressure on the loss of cultivated land. 3) Lastly, 12.54% of the constructive expansion permitted zone and 8.36% of the constructive expansion conditionally permitted zone are situated in an unsuitable area, which indicates that the general planning of Daye lacks the necessary verification of suitability evaluation. Guidance is provided on the development strategy of rural settlement patches to support decision making in general land use planning.展开更多
Land evaluation assesses the suitability of land for specified land uses. The FAO Framework for Land Evaluation provides guidance for land suitability assessment. An Expert System Land Evaluation for Oil Palm Cultivat...Land evaluation assesses the suitability of land for specified land uses. The FAO Framework for Land Evaluation provides guidance for land suitability assessment. An Expert System Land Evaluation for Oil Palm Cultivation (ESLEOP) software was developed using climate, land qualities and land characteristics as diagnostic criteria in order to speed up the process of land assessment for oil palm cultivation in tropical regions. The results showed that ESLEOP evaluated land suitability for oil palm cultivation faster than the conventional method.展开更多
In developing countries, land productivity involves little market, where the agricultural land use is mainly determined by the food demands as well as the land suitability. The land use pattern will not ensure everywh...In developing countries, land productivity involves little market, where the agricultural land use is mainly determined by the food demands as well as the land suitability. The land use pattern will not ensure everywhere enough land for certain cropping if spatial allocation just according to land use suitability. To solve this problem, a subzone and a pre-allocation for each land use are added in spatial allocation module, and land use suitability and area optimi- zation module are incorporated to constitute a whole agricultural land use optimal allocation (ALUOA) system. The system is developed on the platform .Net 2005 using ArcGIS Engine (version 9.2) and C# language, and is tested and validated in Yili watershed of Xinjiang Region on the newly reclaimed area. In the case study, with the help of soil data obtained from 69 points sampled in the fieldwork in 2008, main river data supplied by the Department of Water Resources of Xinjiang Uygur Autonomous Region in China, and temperature data provided by Data Center for Resources and Environmental Sciences, Chinese Academy of Sciences, land use suitability on eight common crops are evaluated one by one using linear weighted summation method in the land use suitability model. The linear pro- gramming (LP) model in area optimization model succeeds to give out land area target of each crop under three scenarios. At last, the land use targets are allotted in space both with a six subzone file and without a subzone file. The resuits show that the land use maps with a subzone not only ensure every part has enough land for every crop, but also gives a more fragmental land use pattern, with about 87.99% and 135.92% more patches than the one without, while at the expense of loss between 15.30% and 19.53% in the overall suitability at the same time.展开更多
Though Ghana's crop yield growth rate was at 17%, 5% of every 1.2 million Ghanaians have insufficient and limited access to nutritious food. Climate change and climate variability have enormously affected the state o...Though Ghana's crop yield growth rate was at 17%, 5% of every 1.2 million Ghanaians have insufficient and limited access to nutritious food. Climate change and climate variability have enormously affected the state of agricultural productivity and hence could result in food insecurity. As many ongoing projects use Boolean suitability analysis, land use planning, management recommendations sores, it still remains inadequate to support rural resource poor farmers. This then, is affecting livelihood and agricultural productivity. In this paper, a geostatistical quantitative method to support a geographic information system (GIS) based on multi-criteria decision support system (GMCDSS) for an enhanced land suitability assessment (LSA) and landuse planning (LP) was devised. Project findings indicated that, recommended farm inputs could be estimated and applied accordingly at farm plot levels Soil amendment indicators (e.g., 1.0 t/ha lime + 1.0 t/ha gypsum was estimated for liming) was quantified and currently, farmers can save money in soil fertility management. It has shown that, instead of applying 5.0 t/ha poultry manure (PM) or five bags of N-P-K fertilizer (rate of 15: 15: 15 N-P2O5-K2O/ha) + two bags of sulphate of ammonia (SA), a farmer may apply 2.0 t/ha PM + two bags 15:15:15 N-P2O5-K2O/ha + one bag of SA. GMCDSS assessment has proved to be fundamental in: (1) urban planning; (2) ensuring food security; (3) poverty reduction and interventions to the effects of climate change and climate variability.展开更多
文摘On the basis of data from Soil Test and Formula Fertilization project in Qimen county,we employed Geographic Information System Software ArcGIS 9.2 and CLRMIS(Cultivated Land Resource Management Information System at County Scale) to establish region-specific estimation index system for tea cultivation in Qimen County by determining the estimation units,and carried out quantitative estimation analysis on tea cultivation there via comprehensive evaluation indices for natural elements of cultivated land.The results showed that the highly suitable,suitable,reluctantly suitable and unsuitable acreages are 5 665.8,8 327.1,8 415.9 and 11 979.9 hm2 respectively,accounting for 24.0%,35.3%,35.7% and 5.1% of the total acreage of cultivated land.These results would facilitate the production of high yield and quality tea in Qimen County.
基金Supported by the National Natural Science Foundation of China(41072196)~~
文摘[Objective] This study was to evaluate the ecological suitability of agricultural land in western Jilin Province, with the aim to provide basis for the effective application of agricultural resources and the structural adjustment of land use. [Method] The evaluation index system was constructed based on fuzzy mathematic method according to the principles of systematic, dominant, effectiveness and feasibility; based on law of tolerance, reasonable evaluation criteria were determined according to the ecological amplitude of crops; based on GIS processing, the initial data completed the mathematical operation by using the VBA program in Excel. [Result] The area of agricultural land grade I was 5 512 km2, grade II of 25 985 km2, grade Ill of 7 907 km2, and area of land not suitable for agriculture was 6 312 km2. According to the evaluation results, the key areas for land use adjustment were Zhenlai County, Da'an County, Tongyu County and western Changling County. The directions of land use adjustment included improving irrigation and drainage conditions, governing land salinization and conversion of cropland to forest and grassland. [Conclusion] This study provided basis for the effective application of agricultural resources and ecological environment construction in western Jilin Province.
基金Supported by National Natural Science Foundation of China(41261018)Lianghe Government Authorized Project~~
文摘According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat area. Then this study deter- mined single evaluation factors index and comprehensive suitability index using "ex- treme conditions method" and "suitability index method", and analyzed and assessed the constructive land suitability on each evaluation unit polygons and its suitability level by using GIS software. Taking Lianghe County of Dehong Dai-Jingpo Au- tonomous Prefecture as an example to evaluate land suitability in Lianghe County's main towns around the gentle slope, the results show, in the evaluation area, the area of land suitable for construction and unsuitable for construction respectively ac- count 73.58% and 26.42%. And first-class, second and third-class of land suitable for construction should be composited at the ratio of about 11:49:40. The suitability evaluation index system and method developed in this paper is applicable for evalu- ating the construction land suitability in mountainous areas of southwest Yunnan Province, and will provide theoretical and technical support for land policy measures which strengthen the protection of farmland and promote the scientific development of urbanization in Yunnan Province and even similar mountainous areas of the whole China.
基金Support by National Natural Science Foundation of China(30590384,30900197)~~
文摘Basing on the limiting factor method and Composite Index method,for the northern China crop-pasture band,the authors established the system of evaluation index,and abstracted the dominant factor,then through applying expert grade and weighing way the suitability of grids are evaluated,the results showed that:without the input of a large number of cash,most of the area was not suitable for farming,and more appropriate area for farming was only 8.45% of total area,mainly located in the southeast and southwest of the study area,followed by the study area in the northeast,areas that was not suitable for farming mainly in the middle of the east,large areas of central and western regions.
基金Supported by the National Basic Research Program of China [2009CB421307 (2009-2013)]the Natural Science Foundation of China [40971282(2010-2012)]~~
文摘[Objective] This study aimed to analyze the sustainability of cropland use in cropping-pastoral ecotone before and after the Grain-for-Green Policy. [Method] Using Yanchi County in Ningxia Hui Autonomous Region as a case study area, this investigation used the annual transfer rate of land use types, cropland suitability and emergy analysis to examine the major pressures affecting the sustainable use of cropland before and after the Grain-for-Green Policy. [Result] The expansion of con- struction land onto cropland was significant; the annual cropland area was still larger than the land area suitable for cropping after the policy; agrochemical inputs used for crop production gradually increased and unit crop outputs required more agro- chemical inputs. Cropland use sustainability showed a fluctuating downward trend. [Conclusion] The results imply that the protection of high quality cropland, further im- plementation of the policy and control of agrochemical inputs according to precipita- tion are the main measures needed for sustainable cropland use in cropping-pastoral ecotone.
文摘Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana, P. ( eurameri cana and P. simonii, which were planted in loess hilly land in northwest Shanxi Province, were tested under different planting densities and site conditions. A randomized block design and three times repetition were adopted in the test. Bas ed on the test results in arid and cold area of the northwest Shanxi, the hybrid poplar trees taking Populus cathaysna as their female parent could be selected for afforestation, such as P. popularis and P. opera, and the growing space of s ingle plant should be larger than 20 m2. P. bolleana as an introduced tree speci es grows well in this area, but its growth is likely affected by ground water co ndition. On the site with relatively abundant soil water, P. bolleana usually su ffer from frost crack at its trunk base. As a result, P. bolleara is suited to p lanting in the site where is short of soil water. P. x euramericana is not suita ble for large-scale afforestation, especially in arid slopes and ridges of loess hilly land .
基金Supported by Yichang Technological Research and Exploitation Project(A2010-302-24)~~
文摘In the view of new rural living environment,problems existing in the construction of current new rural living environment were analyzed so as to propose some theoretical ideas and ways for resolving the problems existing in the design of new rural living environment.
基金Support by Research of Comprehensive Evaluation of Agricultural Land Suitability in Typical Area of Huanghuahai Plain based on GIS(X0810025)~~
文摘The paper aims to study agricultural land suitability in typical agricultural area in Huanghuaihai plain by the comprehensive evaluation of natural factors and environmental conditions of agricultural land with Liaocheng area in Shangdong Province in the center of Huanghuaihai plain as a case.The results suggested that the land quality in Liaocheng was above the average and accorded with the local practical situation.The authors validated the scientificity of agricultural land suitability study by using GIS technology and proposed some suggestions on analysis results.
基金Project(2006BAJ04A13) supported by the National Science and Technology Pillar Program during the 11th Five-Year Plan of ChinaProject(2009FJ4056) supported by the Key Project of Science and Technology Program of Hunan Province,ChinaProject(20090161120014) supported by the New Teachers Fund of Department of Education,China
文摘The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aiming at this limitation,an ecological suitability evaluation analysis model was presented based on fuzzy theory and a research on urban growth boundary(UGB) of the Great-Hexi Leading District(GHLD) of Changsha was conducted.With the support of GIS,RS and MATLAB,slope,elevation,vegetation,soil productivity,soil permeability,water body and land use are selected as the input of model according to the characteristic properties of soil and terrain in red soil hilly areas.The running result of this model indicates that the ratios of highly suitable land,suitable land,moderately suitable land and unsuitable land in GHLD are 18.75%,10.31%,64.16%,6.78%,respectively.This result accords with spatial structure worked out by Space Development Strategy Planning of GHLD,Based on this result,several suggestions are made to guide UGB developments in future.
基金Project supported by the National Basic Research Program of China (No. 2006CB400505)the National Natural Science Foundation of China (No. 40171007).
文摘A GIS-based method was used to assess land suitability in the Qinling Mountains, Shaanxi Province of China through simultaneous consideration of physical features and current land use. Through interpretation of Landsat TM images and extensive field visits the area was modeled into 40 land types in five altitudinal zones (valleys and gullies, hillsides and terraces, foothills, mid-mountain, and sub-alpine mountain). Then, a suitability score was assigned to five physical factors (climate, hydrology, topography, soil, and vegetation). Next, their integrated overall suitability value scores were compared with the observed land cover to determine whether it should be reallocated a new use. Results showed that the five suitability classes of agriculture, forest, grassland, farmland-woodland, and scrub-pasture had altitudinal stratification and a total of 1151 km2 (8.89%) of lands on the northern slopes of the Qinling Mountains had to be reallocated. To achieve this reallocation, 657 km2 of arable land should be reduced, and forest, grassland and scrub-pasture increased by 615 km2, 131 km2 and 405 km2, respectively. Implementation of these recommended land reallocations should help achieve suitable use of land resources and prevent land degradation.
基金Supported by the PhD Programs Foundation of Ministry of Education of China (No. 20093104110002)the National High Technology Research and Development Program of China (863 Program) (Nos. 2007AA092201, 2007AA092202)+2 种基金the National Natural Science Foundation (No. NSFC40876090)the Shanghai Leading Academic Discipline Project (No. S30702)Y. Chen's involvement in the project was partially supported by the Shanghai Dongfang Scholar Program
文摘The eastern fall cohort of the neon flying squid, Ommastrephes bartramii, has been commercially exploited by the Chinese squid jigging fleet in the central North Pacific Ocean since the late 1990s. To understand and identify their optimal habitat, we have developed a habitat suitability index (HSI) model using two potential important environmental variables -- sea surface temperature (SST) and sea surface height anomaly (SSHA) -- and fishery data from the main fishing ground (165°-180°E) during June and July of 1999-2003. A geometric mean model (GMM), minimum model (MM) and arithmetic weighted model (AWM) with different weights were compared and the best HSI model was selected using Akaike's information criterion (AIC). The performance of the developed HSI model was evaluated using fishery data for 2004. This study suggests that the highest catch per unit effort (CPUE) and fishing effort are closely related to SST and SSHA. The best SST- and SSHA-based suitability index (SI) regression models were SISST-based = 0.7SIeffort-SST + 0.3 SICPUE-SST, and SISSHA-based =0.5Sleffort-SSHA + 0.5SICPUE-SSHA, respectively, showing that fishing effort is more important than CPUE in the estimation of SI. The best HSI model was the AWM, defined as HSI=0.3SISSHA-based+ 0.7SISSHA-based, indicating that SSHA is more important than SST in estimating the HSI of squid. In 2004, monthly HSI values greater than 0.6 coincided with the distribution of productive fishing ground and high CPUE in June and July, suggesting that the models perform well. The proposed model provides an important tool in our efforts to develop forecasting capacity of squid spatial dynamics.
基金Application of Information Technology in Testing for Formulated Fertilization~~
文摘Camellia sinensis is an important commercial crop in China. Suitability evaluation of tea tree planting, which is an embodiment of agricultural planting based on Geographic Information System(GIS), includes overlay analysis, hierarchical analysis,artificial intellegence, multivariable linear regression and fuzzy evaluation. Via a series of functions of GIS such as data query, retrieve and management, we can be informed of current situation and problems in tea plant development, find out areas which are appropriate or inappropriate for Camellia sinensis planting and figure out corresponding planting schemes and policies. Science and technology are the basic solution to modernization of Camellia sinensis planting. It is necessary to set up decision information and plantation management systems in agriculture on account of GIS, which are important channels to regionalization of Camellia sinensis planting suitability.
基金supported by the Research Project of Tianjin Earthquake Agency(No.yb201901)Seismic Regime Tracking Project of CEA(No.2019010127)Combination Project with Monitoring,Prediction and Scientific Research of Earthquake Technology,CEA(No.3JH-201901006)
文摘In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal parameters and three-dimensional(3 D)body-wave high-resolution velocity structures at depths of 0–30 km were retrieved by double-difference tomography.Results show that there is a good correspondence between the spatial distribution of the relocated earthquakes and velocity structures,which were concentrated mainly in the high-velocity-anomaly region or edge of high-velocity region.Velocity structure of P-and S-waves in the Yibin area clearly shows lateral inhomogeneity.The distribution characteristics of the P-and S-waves near the surface are closely related to the geomorphology and geologic structure.The low-velocity anomaly appears at the depth of 15–25 km,which is affected by the lower crust current.The Junlian–Gongxian and Gongxian–Changning earthquake areas,which are the two most earthquake-prone areas in the Yibin region,clearly differ in earthquake distribution and tectonic characteristics.We analyzed the structural characteristics of the Junlian–Gongxian and Gongxian–Changning earthquake areas on the basis of the 3 D bodywave velocity structures in the Yibin region.We found that although most seismicity in the Yibin area is caused by fluid injection,the spatial position of seismicity is controlled by the velocity structures of the middle and upper crust and local geologic structure.Fine-scale 3 D velocity structures in the Yibin area provide important local reference information for further understanding the crustal medium,seismogenic structure,and seismicity.
基金Under the auspices of National Natural Science Foundation of China(No.41371429,41401196)
文摘Land suitability assessment is a prerequisite phase in land use planning; it guides toward optimal land use by providing information on the opportunities and constraints involved in the use of a given land area. A geographic information system-based procedure, known as rural settlement suitability evaluation(RSSE) using an improved technique for order preference by similarity to ideal solution(TOPSIS), was adopted to determine the most suitable area for constructing rural settlements in different geographical locations. Given the distribution and independence of rural settlements, a distinctive evaluation criteria system that differed from that of urban suitability was established by considering the level of rural infrastructure services as well as living and working conditions. The unpredictable mutual interference among evaluation factors has been found in practical works. An improved TOPSIS using Mahalanobis distance was applied to solve the unpredictable correlation among the criteria in a suitability evaluation. Uncertainty and sensitivity analyses obtained via Monte Carlo simulation were performed to examine the robustness of the model. Daye, a resource-based city with rapid economic development, unsatisfied rural development, and geological environmental problems caused by mining, was used as a case study. Results indicate the following findings: 1) The RSSE model using the improved TOPSIS can assess the suitability of rural settlements, and the suitability maps generated using the improved TOPSIS have higher information density than those generated using traditional TOPSIS. The robustness of the model is improved, and the uncertainty is reduced in the suitability results. 2) Highly suitable land is mainly distributed in the northeast of the study area, and the majority of which is cultivated land, thereby leading to tremendous pressure on the loss of cultivated land. 3) Lastly, 12.54% of the constructive expansion permitted zone and 8.36% of the constructive expansion conditionally permitted zone are situated in an unsuitable area, which indicates that the general planning of Daye lacks the necessary verification of suitability evaluation. Guidance is provided on the development strategy of rural settlement patches to support decision making in general land use planning.
文摘Land evaluation assesses the suitability of land for specified land uses. The FAO Framework for Land Evaluation provides guidance for land suitability assessment. An Expert System Land Evaluation for Oil Palm Cultivation (ESLEOP) software was developed using climate, land qualities and land characteristics as diagnostic criteria in order to speed up the process of land assessment for oil palm cultivation in tropical regions. The results showed that ESLEOP evaluated land suitability for oil palm cultivation faster than the conventional method.
基金Under the auspices of National Natural Science Foundation of China (No. 41001108, 41071065)Beijing Municipal Natural Science Foundation (No. 9113029)
文摘In developing countries, land productivity involves little market, where the agricultural land use is mainly determined by the food demands as well as the land suitability. The land use pattern will not ensure everywhere enough land for certain cropping if spatial allocation just according to land use suitability. To solve this problem, a subzone and a pre-allocation for each land use are added in spatial allocation module, and land use suitability and area optimi- zation module are incorporated to constitute a whole agricultural land use optimal allocation (ALUOA) system. The system is developed on the platform .Net 2005 using ArcGIS Engine (version 9.2) and C# language, and is tested and validated in Yili watershed of Xinjiang Region on the newly reclaimed area. In the case study, with the help of soil data obtained from 69 points sampled in the fieldwork in 2008, main river data supplied by the Department of Water Resources of Xinjiang Uygur Autonomous Region in China, and temperature data provided by Data Center for Resources and Environmental Sciences, Chinese Academy of Sciences, land use suitability on eight common crops are evaluated one by one using linear weighted summation method in the land use suitability model. The linear pro- gramming (LP) model in area optimization model succeeds to give out land area target of each crop under three scenarios. At last, the land use targets are allotted in space both with a six subzone file and without a subzone file. The resuits show that the land use maps with a subzone not only ensure every part has enough land for every crop, but also gives a more fragmental land use pattern, with about 87.99% and 135.92% more patches than the one without, while at the expense of loss between 15.30% and 19.53% in the overall suitability at the same time.
文摘Though Ghana's crop yield growth rate was at 17%, 5% of every 1.2 million Ghanaians have insufficient and limited access to nutritious food. Climate change and climate variability have enormously affected the state of agricultural productivity and hence could result in food insecurity. As many ongoing projects use Boolean suitability analysis, land use planning, management recommendations sores, it still remains inadequate to support rural resource poor farmers. This then, is affecting livelihood and agricultural productivity. In this paper, a geostatistical quantitative method to support a geographic information system (GIS) based on multi-criteria decision support system (GMCDSS) for an enhanced land suitability assessment (LSA) and landuse planning (LP) was devised. Project findings indicated that, recommended farm inputs could be estimated and applied accordingly at farm plot levels Soil amendment indicators (e.g., 1.0 t/ha lime + 1.0 t/ha gypsum was estimated for liming) was quantified and currently, farmers can save money in soil fertility management. It has shown that, instead of applying 5.0 t/ha poultry manure (PM) or five bags of N-P-K fertilizer (rate of 15: 15: 15 N-P2O5-K2O/ha) + two bags of sulphate of ammonia (SA), a farmer may apply 2.0 t/ha PM + two bags 15:15:15 N-P2O5-K2O/ha + one bag of SA. GMCDSS assessment has proved to be fundamental in: (1) urban planning; (2) ensuring food security; (3) poverty reduction and interventions to the effects of climate change and climate variability.