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1.
农业土地利用对岩溶地下水影响研究综述 总被引：4，自引：4，他引：0
地球表层系统最突出的景观标志是土地利用/土地覆被。人类通过土地利用改变天然土地覆被从而对脆弱敏感的岩溶水文系统产生了重大的影响。文章着重从农业土地利用出发综述了当前农业土地利用对岩溶水影响的研究。农业土地利用对岩溶地下水的影响主要围绕着水质和水量两个核心从以下几个方面展开:天然植被的清除,农业灌溉和排水,农业集约化所带来的化肥杀虫剂等的使用以及污染物质在岩溶含水层中的运移和影响。在此基础上作者从研究内容,理论方法和建立模型等方面都提出了自己的想法和建议。 相似文献
2.
在中小尺度上确定土壤养分状况并准确表达其空间分布特征仍需深入研究,了解和掌握土壤养分现状可为土地资源利用提供一定的科学参考。基于内蒙古东来地区土地质量地球化学调查中采集的468件表层土壤样品分析结果,采用主成分分析法和GIS技术对碱解氮、速效磷、速效钾、有机质4项养分指标进行空间分布特征分析及养分丰缺评价。结果表明,研究区土壤养分属于中度变异,呈不均匀分布。主成分分析提取的2项主成分指标可反映土壤养分指标90.34%的原量信息,得出的土壤肥力综合得分IFI值为-1.643～1.972。空间分布特征显示,研究区土壤整体有机质缺乏,碱解氮稍缺,速效磷适中,速效钾较丰富。IFI值的空间插值结果表明：土壤养分达到丰富及以上的区域占研究区面积的29.35%,主要分布在研究区中部的工农村、七间房附近;达到适中等级的占比为41.74%;稍缺—缺乏等级的占比为28.91%,其中缺乏等级分布面积为10.43%,主要分布在辽河农场三分场附近。建议在研究区进行农林业生产活动时,应注意有机肥和氮肥的增施。 相似文献
3.
Parameter estimation for a karst aquifer with unknown thickness using the genetic algorithm method 总被引：5，自引：2，他引：3
The combination of ecological fragility and agricultural activity in the loess hilly–gully regions of western China has received
broad environmental concerns. In this region, rainfall and soil moisture can fatally influence crop production under dry land
farming. In this study, field experiments were conducted, from March 2001 to September 2005, to demonstrate the variation
of soil moisture and fertilizer contents at different depths in slope and terraced lands, and to evaluate the ecological impacts
and economic benefits in the terraced land of Loess Plateau. The results of both field test and Grey model (GM) calculation
show that the terraced land, as compared to the sloping land, in the agricultural area of the Loess Plateau tends to store
and retain much water, promoting more favorable interactions between water and fertilizer. During the months from March to
June of the year with less rainfall, the water supply for crop growth is mainly derived from the deep storage of soil moisture
accumulated from July to September of the previous year. The field experiments indicate that the crop yield of the 3-year-old
terraced lands was 27% higher than that of the sloping lands with slopes greater than 10°, and that the crop yield can increase
by 27.07 to 52.78% in the following cultivation years. In particular, potato was found to be more drought-resistant than winter
wheat, thus it is more suitable for the arid and semi-arid Loess Plateau regions. 相似文献
4.
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
5.
Mohamed Ismail Siddiqi Dr. 《GeoJournal》1985,10(1):83-89
Conclusion Population growth in Pakistan is alarming. The long and continuing shortage of foodgrains at intervals and increasing competition for land use have resulted in deterioration in yield per hectare, and low reproduction of livestock, although hard struggle is going on for self sufficiency. The margin in food supply has arrived even in those areas where the production has been abundant, and vulnerable to crop failure and other emergency causes. Provision against these dangers call for the maintenance of adequate national reserves, which can be brought into action at an early stage of the emergency.The area under agriculture can be increased through improved programmes of soil conservation and development of barani (rain fed areas) with cost-benefit consideration. Several million hectares of barani areas have fertile soils and are suitable for agricultural development. It has been estimated that 45 billion m3 of river water flows into the Arabian Sea. A part of the water sources is properly harnessed and could possibly change the economic conditions of the barani region. A number of regions are covered by hard texture of the soil, mechanization will have to be introduced in these areas to increase production much beyond the level of margin. Soil conservation measures have already been initiated and in some cases demonstrated to farmers, but the reclaimed virgin lands up to 1973 were very little, just 46.5 ha of virgin lands and 72 ha of cultivated area from the Soan and Potwar uplands. It is expected that 300,000 ha of cultivated area, 10,000 ha of gullied land will be reclaimed through soil conservation methods in the current Fifth Year Plan.Pakistan has great water potential. The remedy lies in wise judicious and scientific water management. Inadequate natural and artificial drainage systems are causing water-logging and salinity. An accelerated programme for recovering lost land is already in operation. Many land reforms were introduced from time to time, but the production result is not of great significance. Restrictions were imposed on consolidated holdings. The economic level of such holding above subsistence have not yet been taken into consideration. It is, therefore, necessary, to make a thorough analysis of agricultural problems, particularly with the foodgrain crops, with reference to population growth, the efforts should continue till the food supply occupies the supreme position by increasing production and reducing the rate of population growth by adopting socio-economic methods. 相似文献
6.
盐渍土资源综合利用的可持续发展观 总被引：1，自引：0，他引：1
大面积盐渍荒地地开发利用和灌区土壤盐渍化土的防治，是推动21世纪我国农业和建筑业大发展的一项重要内容。本文通过讨论盐渍土和盐渍化土对工农业生产的影响，提出了的开发利用盐渍土和盐渍化土的可持续发展观。 相似文献
7.
This study demonstrated the use of fuzzy logic approach in mapping land limitations for agricultural land use planning using publicly available data for the province of Marinduque, Philippines. The paper focused only on the two major crops in the province, coconut, and banana. Based on the results, slope is the major factor limiting the production of these two crops. Slope is identified as a limitation in approximately 80% and 18% of the agricultural land of the province for coconut and banana production, respectively. Other land limitations for coconut production in the province include rainfall, soil, and combination of these factors with slope. In the case of banana, soil and combination of this factor with slope were identified as land limitations.
相似文献8.
以安徽省西南部岳西县来榜地区为研究区,按8个点/km^2的密度采集表层土壤样品,系统分析了该区土壤样品中Cd、Hg、As、Se等21项元素的含量及相关指标特征。采用土地利用现状图斑作为评价单元,参照土地质量地球化学评价规范对来榜地区土地质量进行地球化学评价。结果表明:来榜地区土地环境综合质量状况优质,达到一等环境质量的土地面积占研究区总面积的97.14%;土壤养分综合质量中等以上的土地面积占研究区总面积的88.05%。土地质量地球化学综合等级以二等土地为主,面积占研究区总面积的66.87%;其次为一等土地,面积占研究区总面积的18.57%。研究区土壤整体缺乏硒,但部分茶叶富硒。上述结论可为研究区土地质量生态管理、土地合理规划及利用提供参考。 相似文献
9.
Soil ecosystem functions are derived from plant, animal and microorganism communities and the non-living environment interacting as a unit. Human activities have affected soil ecosystem functions and in many cases caused soil ecosystem collapse. This review provides a synthesis of current knowledge of human impacts on soil ecosystems, with a special focus on knowledge gaps regarding soil ecosystem shifts and tipping points, using the island of Crete, Greece as an example. Soil ecosystem shifts are abrupt changes that occur at “tipping points” and have long-lasting effects on the landscape and both the biotic and abiotic structure of the soil. These shifts can occur due to climate change, land use change, fertilization, or above-ground biodiversity decline. The environmental pressures in the agricultural land of Crete, place the island very close to tipping points, and make it an “ideal” area for soil ecosystem shifts. Reversing the trend of the shift while using the soil ecosystem services, means that significantly more organic matter needs to be added to the soil compared to the amount added under set-aside conditions. Potential nutrient supply and demand calculations indicate that fertilizer demand in Crete can be satisfied by recycling of bio-residue and livestock excreta produced on the island. Soil fertility improves faster if, in addition to bio-fertilization, farmers use traditional agricultural practices such as crop rotations and legume row plantings within olive trees and orchards. A renewed soil fertility paradigm shift requires a “holistic” management of biotic-soil–water resources in order to provide sufficient and an appropriate type of organic matter to the plant–microorganism system to maximize food production. 相似文献
10.
农业区非点源污染潜在危险性评价——以于桥水库流域磷流失为例 总被引：32，自引：0，他引：32
在农业非点源污染研究中,确定农业非点源污染的关键源区或危险区域是开展有针对性研究和控制农业非点源污染的首要问题之一.本文在地理信息系统的支持下,综合考虑了影响于桥水库流域农业非点源磷流失的源因子和迁移因子,通过建立评价指标体系,计算磷污染危险性指数,对农业非点源磷流失危险性进行定量化评价,识别具有极高危险性或较高危险性的区域为磷流失的关键源区,将其作为控制和管理的优先区域和重点区域.结果表明:流域中磷流失危险性极高和较高的区域即关键源区不到全流域面积的6.0%,危险性中等的地区占到整个流域面积的20.52%;具有高和中等危险性的地区主要分布在流域河流两岸,且具有极高或较高的土壤有效磷含量或化肥磷施用量或高的土壤侵蚀强度,大部分为流域中部丘陵平原区的农田,少部分为地形较陡的山区农田. 相似文献
11.
Kishan Singh Rawat Vinod Kumar Tripathi Anil Kumar Mishra 《Arabian Journal of Geosciences》2014,7(8):3131-3145
Assessment of soil loss through Sediment Yield Index (SYI) is important for watershed planning, prioritization, and development. In the absence of measured sediment data, SYI expressing the relative sediment yield from different basins work as a basis for grading another basin to adopt erosion control measures. An attempt was made to evaluate SYI in wider scale by using cost-effective tools like remote sensing and geographical information system (GIS). SYI was calculated for Madia subwatershed, which consists of 29 microwatersheds and located in Sagar District, Madhya Pradesh (M.P.) The IRS LISS III data and Shuttle Radar Topography Mission (SRTM) digital elevation models (DEM) of 90-m resolution were used to identify land use characteristics and geomorphometric analysis. Major land use was observed as agricultural land (24.7 %), water bodies (16.7 %), forest area (10.2 %), and settlement (21.3 %). In categorization, similar overall accuracy was observed for dense forest, barren land, settlement, and water bodies. The highest SYI with a value more than 20 was observed in microwatershed Mw6, Mw7, and Mw24, which comprises 33 % of the total watershed area. It gives the information about the watershed area that requires very high priority. 相似文献
12.
基于遥感影像的决策树分类,结合土地利用图,将北京市农业地表覆盖划分为春玉米、冬小麦、果园、林木苗圃、牧草地、设施农业和畜禽饲养地。考虑海拔、坡度和土壤质地三个因子将北京市分成10个景观区,在景观分区和不同农业用地基础上划分出39类农业景观单元。利用基于遥感影像计算的归一化差异植被指数,结合实地调查验证,分类出北京市冬春季裸露农田。结合景观分类,分析了不同景观单元冬春季地表裸露情况。结果表明：2007—2008年冬春季裸露农田共8.05×104 hm2,主要分布在延庆盆地、密云水库北岸和城区边缘的近郊农业区;海拔和土地利用方式对裸露情况影响较大,其中山区春玉米和平原果园裸露情况绝对面积较大,分别占到总裸露农田面积的40%和17%,牧草地、林木苗圃与设施农业地裸露程度较高。基于不同景观单元裸露程度,结合绿肥种植、保护性耕作、生草覆盖等裸露农田治理方法,探讨了北京市农业产业和景观一体化建设策略。 相似文献
13.
14.
农业地球化学的研究进展及近期内的主要任务 总被引：3，自引：0，他引：3
介绍了国内外农业地球化学研究中有关植物营养元素，有益元素的生理功能，作物吸收，土壤物化条件及影响，肥料施用等方面的成果以及勘查地球化学在农业中研究应用的进展，评述了目前农业地球化学研究中存在的问题；提出了近期内我国农业地球化学研究的主要任务。 相似文献
15.
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. 相似文献
16.
MushtakTalibJabbar 《中国地质大学学报(英文版)》2003,14(4):356-362
Satellite image data and thematic map data were used to provide comprehensive views of surface-bound conditions such as soil and vegetation degradation. The current work applies a computerized parametric methodology, developed by FAO, UNEP and UNESCO to assess and evaluate soil degradation at 1 : 250 000 mapping scale. The study area is located in the arid and semi-arid zone of the northern part of Shaanxi Province in China, a region with considerable agricultural potential; Landsat TM images were utilized to provide recent data on land cover and use of the area. ARC/INFO and Arc-View softwares were used to manage and manipulate thematic data, to process satellite images, and tabular data source. ER mapper software is utilized to derive the normalized difference vegetation index (ND VI) values while field data to estimate soil erodibility (SE) factor. A system is established for rating soil parameters, slope, climate factor and human factor activity. The rating values serve as inputs into a modified universal soil loss equation (USLE) to calculate the present state and risk for soil degradation processes, namely soil wind erosion. The produced maps and tabular data show the risk and the present status of different soil degradation processes. The study area, in general, is exposed to high risk of wind erosion and high hazards of water erosion. Several desertification maps were produced, which reflect the desertification types persisting in the study area. Wind erosion, water erosion, vegetation degradation,physical degradation and salinization are the basic desertification maps, and others are combinations of these basic maps. In terms of statistic analysis, 33.75 % of the total land area (120. 330 0 ha) is considered as sand or sand dune, and not included in our analysis of desertification. About 29. 41% of the total land area has slight or moderate desertification and 37. 465 % is facing severe desertification. 相似文献
17.
随着我国经济的快速发展,大气污染问题日益严重,旅游城市的空气质量问题也备受关注。本文基于2018年30座热门旅游城市的气温和空气质量数据,从气象条件的角度出发,研究了气温与空气质量之间的关系。采用函数型数据描述性分析的方法对空气质量和气温变化特征进行分析,用函数型回归分析研究气温对空气质量的影响。结果显示：函数型线性模型拟合优度R2=0.898 1,F=11.8212大于临界值2.385 9,函数型检验统计量F=8.723 3大于α=0.05水平下的临界值1.7058,说明气温与空气质量的函数型线性关系显著;气温对空气质量呈谐波正负影响交替出现,这与空气质量平均变化相似,在实际生活中是合理的。 相似文献
18.
Investigation of land use changes on soil erosion process using geographical information system 总被引：1，自引：1，他引：0
K. Solaimani Ph.D. S. Modallaldoust S. Lotfi Ph.D. 《International Journal of Environmental Science and Technology》2009,6(3):415-424
Land use change quantified for the last 50 years within and near a fast growing agricultural land in Neka River Basin, using geographic information systems. Land cover and land use change was projected for the next decade using topography, geology, land use maps and remote sensing data of the study area. The study explored the relationships between agricultural land growth and landscape changes. The land use changes assessed among the different land cover classes. It is important to mention that conducting of the present study a very severe land cover changes taken place as the result of agricultural land development. These changes in land cover led to the forest degradation of the study area. Relationship between land-use changes and agricultural growth offered a more robust prediction of soil erosion in Neka watershed. This study aims to find the relationships between land use pattern, erosion and the sediment yield in the study area. The land use coefficient has applied in the model of erosion potential method to forecast the effect of the land type to reduce the erosion. The results of this study indicated that the total sediment yield of the study area has notably decreased to 89.24 % after an appropriate land use/cover alteration. The estimated special erosion for the southern Neka Basin is about 144465.1 m3/km2 where after management policy is predicted 15542.9 m3/km2/y. Therefore, the total difference for the study area has estimated about 128922.2 m3/km2/y. 相似文献
19.
土地质量地球化学评估与绿色产能评价研究:以吉林大安市为例 总被引：4，自引：0，他引：4
做好土地资源数量管控,加强耕地质量管理和生态管护是当前的一项非常重要的工作。选择吉林省大安市东南区域为研究对象,进行土地质量地球化学评估,并融合污染元素进行农用地分等研究。结果表明研究区内评定为三等及以上的土壤占全区总面积的72.61%,研究区土地质量总体较好,优质和优良土地分布面积较大,主要为黑钙土,差等的土地主要为盐碱土或盐化草甸土。尝试性地将农用地分等成果中的产能评价和土地质量地球化学评估中的元素含量评价结合,开展了绿色产能评价。 相似文献
20.
J. Pushpamalar S. J. Langford M. B. Ahmad Y. Y. Lim K. Hashim 《International Journal of Environmental Science and Technology》2018,15(10):2059-2074
In the agricultural industry, biomass waste generated along with the production of food, is transformed into value-added products. Also, the demand for the slow or control release fertilizer is increasing to reduce the cost of maintaining the agricultural land. These issues are tackled by converting biomass waste to a slow fertilizer release vehicle and biodegradable water retention material that could reduce the cost for fertilizer application and simultaneously preserved the soil from dryness. A series of carboxymethyl sago pulp (CMSP) hydrogels were prepared by electron beam irradiation. Slow release systems were evaluated by loading potassium nitrate (KNO3) and ammonium nitrate (NH4NO3) into the CMSP hydrogels. These CMSP hydrogels endow slow release property, biodegradability and a soil moisture preservation property that could find greener application in agricultural industries. The results indicate that CMSP hydrogels have a great potential as an agent for slow release of fertilizers. 相似文献