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1.
2005-2010年河南省土地利用结构变化分析   总被引:1,自引:0,他引:1  
土地利用结构变化是实施土地利用总体规划关注的核心内容。根据2005年和2010年的2期土地利用空间数据,运用GIS技术和土地利用转换矩阵等方法,分析了2005—2010年河南省土地利用结构的变化。从全省来看,土地利用结构的数量变化主要表现为:城乡工矿居民用地和未利用地增加(增幅分别为6.71%和16.97%),而耕地和水域减少(减幅分别为1.26%和0.98%)。空间变化主要表现为:耕地与林地、耕地与水域、耕地与城乡工矿居民用地之间的空间位置的变换,以及水域向未利用地的转变。从土地利用综合区来看,土地利用结构的数量变化主要表现为:各区城乡工矿居民用地增加(增幅为3.70%~16.71%),耕地减少(减幅为0.48%~2.15%)。此外,中原城市群区未利用地和林地的增加、水域的减少,豫北区林地和水域的减少,豫西南区水域的增加,以及黄淮四市区草地的增加也较显著。空间变化主要表现为:各区耕地和城乡工矿居民用地之间的空间位置的变换。此外,中原城市群区耕地和林地、耕地和水域之间的位置变换,豫北区林地和水域向耕地的转变,豫西南区耕地向水域的转变,以及黄淮四市区耕地和水域之间的位置变换、耕地向草地的转变也较显著。研究结果为河南省土地利用总体规划(2006—2020)的实施提供了科学依据。  相似文献   

2.
陕西省2000-2018年土地利用时空演变及驱动因素   总被引:2,自引:1,他引:1  
[目的] 分析陕西省土地利用变化及驱动因素,为促进该省土地资源综合优化配置和社会经济可持续发展提供科学依据。[方法] 基于2000,2010和2018年陕西省的土地利用遥感监测数据,通过土地利用动态度、土地利用转移矩阵、空间自相关等方法定量分析陕西省土地利用的时空演变特征,并利用主成分分析法对其土地利用变化的驱动力进行分析。[结果] 各土地利用类型面积均有不同程度的变化。其中,耕地面积下降最多,工矿建设用地面积增速最快,水域面积变化最小。土地利用类型受自然条件的影响,空间差异性显著。农村居民用地、未利用地、耕地、林地、草地的空间聚集性强,水域、城镇居民用地和工矿生产用地的空间集聚性性相对较弱,草地、工矿建设用地形成新的集聚区。陕北高原和关中平原土地利用转移相对频繁,陕南山区土地利用转换相对较小。榆林市和延安市主要表现为耕地向林地和草地转移以及未利用地和草地向工矿建设用地转移,西安市主要表现为耕地和农村居民用地向城镇居民用地转移。土地利用变化的主要因素是城市化发展过程中社会经济的发展以及产业结构的调整。[结论] 陕西省土地利用变化区域差异较大,应因地制宜制定土地利用规划,促进人口—经济—生态之间的协调发展。  相似文献   

3.
绿洲城市是干旱区人地关系最为敏感的区域,以TM/ETM+影像为主要数据源,借助遥感、GIS技术和数理统计方法,从数量和空间迁移等角度对典型绿洲城市——奎屯市近16a来的土地利用变化进行了分析。结果表明:奎屯市1993—2009年土地利用发生了显著变化,以耕地、城乡工矿居民用地增加及草地减少为主要特征;土地利用变化整体呈现出时空不均衡、各地类间更替转换程度大、城乡差异明显等特点;土地利用结构上,优势地类草地减少,耕地和城乡工矿居民用地增加,林地2001—2009年增加显著,水域和未利用地变化幅度相对较小;土地利用类型转换上,6大地类间发生了较大程度的更替转换,东部市区以城乡工矿居民用地和林地增加为主要特征,而西部开干齐乡则主要体现在耕地和草地之间的更替;变化趋势上,耕地、林地和城乡工矿居民用地面积会有所增加,而草地、水域和未利用地则呈减少的趋势。  相似文献   

4.
基于分维模型的台兰河流域土地利用变化研究   总被引:5,自引:0,他引:5  
以新疆台兰河流域1990年、2000年和2005年土地利用数据为例,将分形理论应用于土地利用空间分布及其变化的研究中,定量分析干旱内陆河流域土地利用空间结构复杂性、稳定性以及各土地利用类型随时间的变化趋势,从而阐述不同土地利用类型的空间分布规律。结果表明:各种土地利用类型都具有空间分形特征,分维数是面积、斑块数量和平均斑块面积等单项指标有机结合的综合表现,是综合表征土地利用变化空间格局的定量指标。1990年、2000年和2005年不同土地利用分维数的排序分别为:水域工矿居民用地耕地草地未利用地林地;水域工矿居民用地草地耕地林地未利用地;水域工矿居民用地草地林地耕地未利用地。1990年、2000年和2005年台兰河流域整体土地利用分形维值分别为1.5993,1.5986,1.6079,流域土地利用的分维数呈现先减后增的趋势,土地利用空间结构趋于复杂化,土地利用类型有扩张的趋势。1990年、2000年和2005年台兰河流域整体空间结构稳定性指数分别为0.1720,0.1563,0.1435,说明整个流域土地利用类型的空间结构稳定性逐渐下降。  相似文献   

5.
[目的]研究陕西省榆林市神木县大柳塔镇近年来的土地利用变化情况,为该区域土地资源的合理开发和利用提供可靠依据。[方法]基于2010,2015年的2期高分辨率遥感影像,通过图像解译提取该地区的土地利用信息,生成土地利用转移矩阵,对2期数据进行统计分析与评价。[结果]2010—2015年,耕地、居民地及工矿交通用地、水域及水利设施用地、草地等用地面积增加,林地、沙地、裸地等用地面积减少。[结论]研究区的土地利用程度较高,结构趋于合理。  相似文献   

6.
1995-2015年上海市土地利用及其景观格局变化   总被引:4,自引:3,他引:1  
范丽娟  田广星 《水土保持通报》2018,38(1):287-292,298
[目的]揭示快速城市化过程中城市景观生态变化的时空规律,为当地编制土地利用规划提供科学依据。[方法]基于5期遥感影像数据,借助GIS技术与Fragstats等软件,分析1995-2015年上海市土地利用及其景观格局的动态变化情况。[结果]1995-2015年上海市耕地、草地以及水域呈减少趋势,林地呈现先减少后增加的趋势,城乡、工矿和居民用地呈现不断增加的趋势;耕地的动态度明显,而草地的土地利用动态程度最弱,单一土地利用类型的动态度在2000-2005年多发生剧变,综合土地利用动态度呈现先增加后减少再增加的年际波动规律;土地利用类型转化主要发生在耕地和城乡、工矿和居民用地、耕地和林地之间的相互转化,以耕地的转出和城乡、工矿和居民用地的转入为主要特征;上海市景观格局在时间上表现为斑块数目不断增多,景观破碎度呈现越来越高的主要特征;在空间上表现为景观多样性指数从中部高、四周低的趋势逐渐转化为中西部、北部部分高的趋势。[结论]城市在未来发展过程中要进一步提升用地潜力,提高土地集约利用度,保护并且增加生态服务功能性用地。  相似文献   

7.
小江流域土地利用变化及其趋势分析   总被引:1,自引:0,他引:1  
运用遥感和地理信息系统技术,提取了小江流域1987,1995年和2000年土地利用空间数据,分析了1987~2000年间小江流域土地利用类型变化的幅度、速度以及类型之间相互转移,并应用马尔柯夫概率模型对小江流域2015年土地利用格局进行了预测。结果表明:13年来小江流域耕地、林地以及城乡工矿用地面积均显著增加,其中耕地增加最为显著,由1987年的345.1km^2增加到2000年的398.7km^2。小江流域土地利用变化速度很快,年均变化速度达0.49%;对单一土地利用类型来说,城乡工矿用地的年均变化速度最大,年变化率达3.52%,其次为耕地和水域。增加的耕地主要来自草地、林地和水域;林地中除部分转化为耕地外,由12.64%的林地退化成草地;草地和未利用地基本保持不变。到2015年,小江流域耕地、林地、水域和城乡工矿用地面积和比例将会增加,草地和未利用地面积和比例将会下降。  相似文献   

8.
环京津冀北贫困带土地利用/覆被变化研究   总被引:1,自引:0,他引:1  
运用地理信息系统空间分析技术、数理统计分析方法及景观生态学方法分析了环京津冀北贫困带1985—2000年土地利用变化的时空格局和演进态势,以期为冀北贫困带实现土地资源可持续利用和社会经济可持续发展科学决策提供依据。结果表明:1985—2000年,冀北贫困带林地和城乡工矿居民用地面积大幅度增加,耕地、草地、水域、未利用地大面积减少。增加的林地主要来源于草地和耕地,新增城乡工矿居民用地主要来源于耕地,未利用地主要转化为草地和耕地。土地利用多样性程度和破碎度降低,聚集度增加。耕地破碎程度增加,但形状趋于规整。其它土地类型均向规则、连片方向发展。  相似文献   

9.
巫山县地处三峡库区腹地,不仅是三峡移民安置区重点建设区域之一,更是研究三峡库区土地利用变化的典型个案。以巫山县1990年和2010年的Landsat TM遥感数据为主要数据源,基于RS和GIS技术获取研究区的土地利用数据,应用土地利用变化模型探究该区域20年间土地利用时空演变特征,借助Markov模型建立其土地利用格局预测,探究今后土地利用类型变化特征和发展趋势。结果表明:研究区地利用类型总体呈现出以林地、草地和耕地为主体的农林生产格局现状;20年间林地、草地、园地、水域和居民工矿用地面积增加,耕地和未利用地面积减少,水域和耕地面积增加和减少的最多,分别为47.67km~2,136.10km~2;林地和水域具有较高的未变化率(保留率),未利用地变化率最小,林地和耕地之间具有较高的转换率,林地新增面积最大,变化速率最小,居民工矿用地变化速率最大;2090年后,研究区土地利用基本达到相对稳定状态,林地、耕地、草地、水域、居民工矿用地、未利用土地和园地的面积比重分别为52.96%,6.15%,26.69%,8.71%,1.38%,0.04%和3.97%。  相似文献   

10.
基于马尔柯夫模型的漾濞江流域土地利用变化预测   总被引:1,自引:0,他引:1  
为了掌握漾濞江流域土地利用的演变趋势,优化土地利用结构,实现土地的可持续利用,在遥感和地理信息系统技术的支持下,利用1990年和2001年的遥感影像作为信息源,获取漾濞江流域土地利用类型数据,结合马尔柯夫模型确定相应的转移概率矩阵,据此分析土地利用各类型间的相互转化情况,并应用马尔柯夫模型和单一土地利用动态度对土地利用的演变趋势进行分析。结果表明:土地利用类型之间的相互转化突出表现为耕地、林地、草地之间的相互转化以及耕地向城乡工矿居民用地的转化;林地面积将趋于稳定,仍为研究区的主要土地利用类型,耕地、草地面积继续减少,水域、城乡工矿居民用地面积稳步增加;必须采取有效措施,解决好耕地保护和城乡发展之间的矛盾,实现当地的可持续发展。  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

14.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

15.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

16.
李聃枫  朱春梧 《土壤》2020,52(3):561-566
自20世纪60年代"绿色革命"以来,育种技术和农耕技术的发展促进了农作物产量的大幅提升,然而作物的营养品质出现下降趋势。在相似的遗传背景下,大气CO_2浓度升高会使单位体积农作物产品的营养元素含量下降,因此"绿色革命"至今,农作物产品的营养元素下降可能受大气CO_2浓度升高影响。通过植物生长箱模拟"绿色革命"初期和目前的大气CO_2浓度水平(310μmol/mol和400μmol/mol),针对主要C_3作物水稻、小麦和大豆,研究"绿色革命"以来大气CO_2浓度升高对其籽粒的C、N、Fe、Zn元素含量的影响,结果表明:CO_2浓度升高对3种作物籽粒的C元素含量几乎没有影响,变化幅度在±1.5%之间;籽粒的N、Fe、Zn元素含量普遍呈现下降趋势,但均未达到显著水平。  相似文献   

17.
Discovery and incorporation of genes from wild species provide means to sustain crop improvement, particularly when levels of resistance in the cultigens are low and virulent strains of pests and pathogens overcome the host plant resistance. The extent of utilization and the potential of the wild genepool for genetic enhancement were reviewed in five important food crops viz. sorghum, pearl millet, chickpea, pigeonpea and groundnut grown in the semi-arid tropics. Introgression from compatible wild germplasm in the primary gene pool resulted in transfer of new cytoplasmic male sterility systems in pearl millet and pigeonpea, development of high protein, cleistogamous flower and dwarf pigeonpea lines and foliar disease resistant groundnut cultivars. Utilization of wild species in secondary and tertiary gene pools has been generally limited due to sterility, restricted recombination or cross incompatibility. Nevertheless, these species are extremely important as they contain high levels of resistance to several important biotic and abiotic stresses. Several of them, like those belonging to the Parasorghum section and the rhizomatous Arachis species are sources of multiple resistances and hold great promise to sustain crop productivity.  相似文献   

18.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

19.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

20.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

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