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1.
吉林省德惠市土壤特性空间变异特征与格局   总被引:33,自引:0,他引:33  
基于区变量理论,通过地统计学的半变异函数定量研究吉林省中部德惠市土壤有机质、全氮、速效钾和速效磷的空间异质性特征。表明土壤有机质的理论模型属于球状模型、全氮和速效钾的理论模型为指数模型、速效磷则属于有基台值的线状模型。空间结构上,有机质具有很强的空间相关性,全氮和速效钾的空间相关性属于中等程度,而速效磷则具有弱相关性。四种土壤养分的空间自相关范围具有明显的差异,有机质和全氮的有效变程最大,速效钾次之,速效磷的有效变程最小。受研究区形状、地形及土壤母质区域性差异的影响,速效磷各向同性显著,其他养分各向带状性比较明显。根据空间分异的分析结果,在GIS支持下,采用Kriging和IDW两种插值方法,分析研究区土壤养分的空间格局,表明土壤有机质、全氮、速效钾均自东北向西南有规律地分布;速效磷分布的随机性较强,较前三者结构性特征不明显。  相似文献   

2.
吉林省西部土地沙化动态变化   总被引:1,自引:0,他引:1  
The sandy land of the western part of Jilin Province is located in the ecotone of semi-humid and semi-arid area in the temperate zone of China. The sandy desertification has widely spread in the region because of the vulnerable natural conditions and the unreasonable human activity; as a result of this, the precious land resources and the economic development in the area have been seriously impacted. In this paper, the sandy land ecologic environment geographic information system is established based on the multi-spectral, multi-temporal Landsat TM images and field investigation. The comprehensive indexes of sandy desertification extent assessment which include vegetation degradation, wind erosion extent and soil depth are presented to classify the sandy land in western Jilin into three levels--slight, moderate and severe sandy desertification with the support of GIS platform. The results demonstrate that the sandy desertification has been partly controlled in the past twenty years, except some small sites. However, this doesn‘t necessarily mean that there is nothing for more concern. The two main causes of sandy desertification have not been eliminated yet, one is its natural factor, especially the physical and chemical characters of sandy soil and dry climate; another is the immoderate economic activity of human being that has highly accelerated the sandy desertification process.  相似文献   

3.
上海城市热环境的空间格局分析   总被引:46,自引:13,他引:46  
城市热环境是城市空间环境在热力场中的综合表现,通过对城市热环境的研究可以揭示城市空间结构、城市规模的发展变化。在RS、GIS的支持下,研究城市热环境的空间格局分析方法。借鉴景观生态学的研究方法,首次提出热力景观观点用以研究城市热环境空间格局,创建了热力景以空间格局的评价体系(总体评价指标、类评价指标、块评价指标)。对不同时期上海城市热环境的空间结构与格局进行了研究,使传统的对热环境空间格局的定性研究进入了定量阶段。  相似文献   

4.
克拉玛依地区土壤速效微量养分空间变异特征   总被引:10,自引:5,他引:10  
用地统计学方法研究了克拉玛依地区土壤速效微量养分的空间变异特征 ,并绘制了微量养分空间分布图。结果表明 :土壤速效微量养分在整个研究区内均表现出中等变异水平 ,其变异性大小表现为 :速效Mo >速效B >速效Mn >速效Zn。除速效硼外 ,其它微量元素都表现出很强的空间结构性 ,速效Zn、Mn变程较短 ,分别为 8.7km和 5 .2km ,速效Mo、B变程较长 ,分别为 4 1km和 6 6 .4km。基于半方差函数模型 ,用普通克里格法对研究区土壤速效微量养分进行了克里格插值 ,结果表明 :速效Zn在研究区内普遍缺乏 ,速效B、速效Mn含量较丰富 ,而速效Mo含量在整个研究区表现出明显的差异性。  相似文献   

5.
基于区域变量理论,在GPS和GIS技术支持下,通过地统计学的半变异函数和Kriging空间插值,以岳普湖绿洲为例,定量分析塔里木河源流区绿洲不同层次土壤盐分的空间异质性。结果表明:0~30cm、30~60cm和60~100cm土壤盐分半方差函数的理论分布模型属于指数模型,100~200cm属于球状模型。不同土层之间的空间自相关范围具有明显的差异,由表层至深层,土壤盐分的自相关范围逐渐增大。土壤盐分的空间格局分析表明,在水平方向上,研究区各层土壤盐分的高值区主要集中分布在人类活动强烈、靠近河渠水源和地势较为低洼区域;在垂直方向上,土壤表层盐分含量最高,向深层逐渐减少。  相似文献   

6.
地下水位变化对干旱区植被盖度的影响及其空间变异特征   总被引:5,自引:0,他引:5  
Sampling and testing are conducted on groundwater depth and vegetation coverage in the 670 km^2 of the Sangong River Basin and semi-variance function analysis is made afterwards on the data obtained by the application of geo-statistics. Results showed that the variance curve of the groundwater depth and vegetation coverage displays an exponential model. Analysis of sampling data in 2003 indicates that the groundwater depth and vegetation coverage change similarly in space in this area. The Sangong River Basin is composed of upper oasis, middle ecotone and lower sand dune. In oasis and ecotone, influenced by irrigation of the adjoining oasis, groundwater level has been raised and soil water content also increased compared with sand dune nearby, vegetation developed well. But in the lower reaches of the Sangong River Basin, because of descending of groundwater level, soil water content decreased and vegetation degenerated. From oasis to abandoned land and desert grassland, vegetation coverage and groundwater level changed greatly with significant difference respectively in spatial variation. Distinct but similar spatial variability exists among the groundwater depth and vegetation coverage in the study area, namely, the vegetation coverage decreasing (increasing) as the groundwater depth increases (decreases). This illustrates the great dependence of vegetation coverage on groundwater depth in arid regions and further implies that among the great number of factors affecting vegetation coverage in arid regions, groundwater depth turns out to be the most determinant one.  相似文献   

7.
GIS支持下的吉林省西部生态环境脆弱态势评价研究   总被引:42,自引:9,他引:42  
黄方  刘湘南  张养贞 《地理科学》2003,23(1):95-100
由于自然条件的边缘性和过渡性,吉林省西部生态系统脆弱性和敏感性显著,其土地利用呈现农牧业交错的过渡特征,是全球和我国土地利用/覆被变化(LUCC)研究的典型区和首选区。基于GIS技术的空间分析功能,建立了基本评价因素的数字环境模型。应用主成分综合分析方法,提出了生态脆弱态势指数模型,获取了吉林省西部近15年生态环境脆弱性变化的空间分布规律,以期为区域生态环境的治理与建设提供依据。  相似文献   

8.
松嫩平原中西部湖泊底泥营养盐的空间变异特征   总被引:3,自引:0,他引:3  
在GIS技术的支持下,利用地统计学方法分析了松嫩平原中西部湖泊底泥营养盐的空间变异特征,并利用Kriging插值方法绘制了研究区营养元素的空间分布图。研究结果表明,通过块金值与基台值的比值C0/(C0+C1)可以得出总有机碳TOC具有较弱的空间相关性,总磷TP和全氮TN具有中等的空间相关性;Kriging插值表明,松嫩平原中西部地区的湖泊底泥营养盐分布格局是西南地区低于北部地区,北部地区的各项指标均超过全区的平均水平。  相似文献   

9.
王冰  安慧君  吕昌伟 《干旱区地理》2013,36(6):1103-1110
呼伦湖是内蒙古第一大湖,在草原生态环境保护中举足轻重。在气候变化和人类活动的影响下,呼伦湖的水环境状况不容乐观。为了掌握呼伦湖水体的水质状况,在实地采样的基础上,基于地统计学半方差函数理论和GIS克立格空间插值方法,定量分析了呼伦湖水体溶解氧含量的空间变异特征及分布格局。结果表明:溶解氧的半方差拟合最优模型为球面模型,该水质参数具有强烈的空间自相关性;空间分布上,结合地表水环境质量标准,呼伦湖大部分水域的水质为IV类;考虑到鱼类等水生生物的生存需要,呼伦湖整体的溶解氧状况基本适合鱼类的生长,其中比较适合的区域分布在湖中部。  相似文献   

10.
塔里木河下游表层土壤盐分空间变异和格局分析   总被引:7,自引:3,他引:7  
土壤盐化是造成塔里木河下游天然植被退化的主要因素之一,应用地统计学方法,分析了塔里木河下游表层土壤盐分的空间异质性特征。结果表明,研究区土壤含盐量普遍较高,表层土壤盐分呈现强变异性和具有较强的空间自相关格局,主要受结构性因子影响。空间插值结果表明,表层土壤盐分整体上呈现出条带状的分布格局,局部地区表现出斑块状的空间变异特征。从河流纵向看,表层土壤盐分“两头高,中间低”;从河流横向看,离河道越远,盐分越低,地下水埋深逐渐加深,物种数和植被盖度分别表现出与之相应的递减趋势。  相似文献   

11.
Based on regionalized variable theory, semivariograms of geo-statistics were used to research the spatial variation of soil properties quantitatively. The results showed that the semivariogram of soil organic matter is best described by spherical model, the best model for semivariograms of soil total N and available K is exponential models and that of available P belongs to linear with sill model. Those soil properties have different spatial correlations respectively, the lag of organic matter is the highest and that of available P is the lowest, the spatial correlation of N and available K belongs to moderate degree. Spatial heterogeneities are different too, the degree of organic matter and total N are higher, the degree of available K is in the next place and that of available P is the lowest. Influenced by the shape, topography and soil of the study area, all isotropies of available P are obvious in all directions while anisotropies of others are manifested. According to the analytical results, supported by GIS, Kriging and IDW methods are applied to describe and analyze the spatial distribution of soil properties. The results indicate that soil organic matter, total N and available K are distributed regularly from northeast to southwest, while available P is distributed randomly.  相似文献   

12.
1IntroductionSoil nutrient, as the synthetic results under the influence of various anthropogenic activities and the factors such as climate and topography, etc., possesses certain spatial distribution characteristics, and certain structural and stochastic characteristics. The study of the differences existing in different parts of the region lays the foundation for adjusting all management measures and all material input capacities and for gaining the maximal economic benefit. Presently, the …  相似文献   

13.
苏南典型区土壤基本性质的时空变化--以昆山市为例   总被引:12,自引:0,他引:12  
以昆山市为例对苏南典型区土壤基本性质的时空变化进行了研究。结果表明:(1)与第二次土壤普查相比,该区土壤酸化严重,土壤上层pH值的平均值由7.20下降到6.42,土壤上层pH值小于6.0的样点多达36.51%;土壤有机质含量呈下降趋势,土壤上层有机质含量平均值由31.4 g/kg下降到28.3 g/kg,小于20 g/kg的土壤样品由0.56%上升到11.11%;速效磷含量总体上呈现明显的升高趋势,平均值由6.4mg/kg上升到89.1 mg/kg;阳离子交换量(CEC)由19.3 cmol/kg下降为17.8 cmol/kg。(2)不同功能区、不同地貌区及不同剖面层次的土壤基本性质存在较为明显的空间变化。  相似文献   

14.
Integrated nutrient management is important for sustainable agricultural production and protecting environment quality and has been widely investigated around the world. In this article the spatial variability of soil nutrients was investigated and a regionalized nutrient management system was developed using geostatistics and geographic information system technologies. A total of 511 GPS-referenced soil samples were taken in Yongji County, Shanxi province, China, and analysed for major soil nutrients: soil total nitrogen (TN), Olsen extractable phosphorus (OLSENP) and extractable potassium (EXTK). Low concentrations of nitrogen (N) and phosphorus (P) were found and they are likely to be the main limiting nutrients for crop growth in this county. Within the county moderate spatial dependence was found for all three soil variables, but at different spatial scales. The spatial distributions of TN, OLSENP and EXTK were estimated by using kriging interpolation. The cropped areas of the county were divided into fertilizer management categories consisting of four classes of TN, three classes of OLSENP and two classes of EXTK. For the targeted crop yields, regionalized fertilization maps of N, P and K in the county were produced using geographic information system. In 3-year field verification trials in two villages the crop yields of the wheat–maize rotation system increased by 10–20%, and farmers' cash income increased by 1550–2610 RMB ha?1 year?1 where regional fertilization recommendations were implemented, in comparison with traditional farmers' practices. The regionalized maps are a practical alternative to site-specific soil nutrient management approaches in areas where it is not practical, because of small farm size or other constraints, to use intensive soil sampling and chemical analyses.  相似文献   

15.
克拉玛依干旱生态农业区土壤质地的空间异质性研究   总被引:13,自引:1,他引:13  
土壤具有高度的空间异质性,而地统计学方法已经被证明是研究土壤空间分布的最有力工具,质地作为一项重要的土壤物理特征,研究其在空间上的异质性在农业中具有重要意义。应用地统计学方法,对克拉玛依干旱生态农业区0~30 cm、30~60 cm、60~100 cm土层进行了土壤质地的半方差函数分析,结果表明:在整个研究区范围内,不同粒径土壤颗粒组成特点类似,均以粉粒平均含量最高,通体土壤颗粒的变异性都很强,尤以砂粒最为突出。研究区内除底层粉粒外,变异半方差模型都为球状模型,各土层土壤颗粒都表现出较强的空间结构性,空间相关距在6~9 km左右。基于半方差模型,用普通克里格法对研究区0~30 cm土层不同粒径土壤颗粒进行插值,表明土壤颗粒的分布情况和研究区地质地貌的分布特点相吻合。  相似文献   

16.
潘明溪  张丽娟  曲成军  潘涛  张帆 《地理研究》2021,40(4):1111-1124
春季土壤湿度是影响东北粮食产量和品质的重要因素.在气候变暖的背景下,东北春季土壤湿度如何变化,鲜有研究.本文基于1983-2019年黑龙江省22个农业气象站的土壤湿度和气象观测资料,采用方差分析、突变分析及空间分析等方法,分析20世纪80年代以来黑龙江省春季土壤湿度的时空变化特征及其影响因素.结果 表明:1983-20...  相似文献   

17.
三工河流域绿洲土壤有机碳的空间分布   总被引:1,自引:0,他引:1  
为理解大尺度下土壤有机碳的空间分异特征,运用遥感与GIS技术,结合地统计学方法研究了三工河流域农业绿洲0~20 cm土层土壤有机碳的空间格局特征。结果表明:①流域尺度的土壤有机碳含量的理论变异函数符合球形模型,F检验达到极显著水平,在2~20 km的中尺度上具有中等强度的空间变异性和自相关性;②流域空间尺度上,土壤有机碳主要变化在4.5~6 g\5kg-1和10.5~12 g\5kg-1范围中,阜康绿洲区土壤有机碳含量明显要高于阜北绿洲区。土壤有机碳平均含量耕地最高,其次为草地,最低的为裸地。流域空间土壤有机碳储量为17.07×105 t,单位面积土壤有机碳储量:阜康绿洲>全流域>阜北绿洲。  相似文献   

18.
科尔沁不同类型沙地土壤水分在降水后的空间变异特征   总被引:6,自引:3,他引:6  
采用地统计学的方法,研究了科尔沁沙地受轻度干扰的沙质草场、禁牧半流动沙地和受重度干扰的丘间低地在降水后的土壤含水量空间变异性。结果表明,土壤含水量变异幅度是丘间低地>半流动沙地>沙质草场。半流动沙地和丘间低地的表层与亚表层土壤水分空间结构差异较小,但土壤水分空间变异性都要高于沙质草场表层。沙质草场表层与亚表层空间结构差异明显,两层土壤含水量变程分别为181.80 m4、.55 m,分维数为1.91、1.99,表层变异性小,亚表层变异性大。半流动沙地表层、亚表层的土壤含水量由随机因素引起的空间变异性,分别占各自总空间变异性的50%和48%,主要表现在1 m以下的小尺度范围内。丘间洼地两层土壤含水量变异特征差异较小,空间变异性大,土壤水分空间格局图表现出由洼地中心向四周递减的分布趋势,但存在一定的尺度范围。由于自然环境的改变和人类活动的干扰,影响着沙地植被、地形小尺度分布格局在大尺度上的配置格局,降水后的沙地土壤水分格局也发生相应的变化,而地形状况、植被条件和小尺度的人为局部干扰在该变化中有着深远的影响。  相似文献   

19.
干旱区典型流域土壤微量元素的空间变异特征研究   总被引:10,自引:0,他引:10  
采用地统计方法,以新疆三工河流域为例,研究了干旱区流域土壤微量元素的空间异质性特征。结果表明,四种微量元素为对数正态分布;流域内土壤微量元素的空间异质性明显,微量元素含量绿洲区普遍高于荒漠区;其中,有效铁和有效锌含量基本属正常范围,有效锰含量处于普遍缺乏状态,有效铜含量较高;微量元素变异系数在42.28%~83.24%;四种微量元素含量空间变异具有各向异性特征,为中等强度的空间自相关性,表现为二阶趋势效应。用简单克立格法进行最优内插,考虑各向异性及趋势效应,制作研究区土壤微量元素含量的等值线图,分析结果表明其具有明显的空间分布规律。利用地统计学方法,对认识本区土壤微量元素的空间变异结构,流域农业生产合理布局、土壤资源综合治理都具有重要的意义。  相似文献   

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