首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
山东滨海低平原区盐渍土盐分的时空变异研究   总被引:2,自引:0,他引:2       下载免费PDF全文
文章运用地统计学的方法对山东滨海盐渍土年际空间变异和分布特征差异进行分析研究,结果表明:黄河三角洲表层土壤的盐渍化程度较高且在年际变化上呈积盐趋势,莱州湾南岸则呈脱盐趋势但盐渍化面积增加;山东滨海低平原区盐渍土受结构因素的影响加剧;表层土壤盐分的分布规律与地形有密切关系,盐渍化类型与盐渍化程度的分布特征基本吻合;莱州湾南岸应注意防止土壤碱化。由此提出因地制宜综合开发、减少土壤盐分输入、加强盐分淋洗、改善土体性质和防止土地碱化等建议,对滨海地区后备土地水土资源的开发利用具有指导作用。  相似文献   

2.
运用经典统计学和地统计学的方法研究了莱州湾南岸地区不同土地利用和土地覆被下土壤盐分含量的特征及分布情况。研究结果表明:不同空间位置不同层位的土壤盐分含量差异性较大;土壤盐分含量表现出盐田>棉花>林地>杂草>大豆>玉米的现象;除林地60~90 cm土壤盐分变异系数具有强变异外,其它各层土壤盐分含量均具有中等变异性;表层土壤盐分含量具有中等空间自相关性,其它土层土壤盐分含量具有强的空间自相关性;研究区各层土壤盐分的空间分布均表现出条带状和斑块状格局,以轻盐渍化和中度盐渍化为主。  相似文献   

3.
针对莱州湾南岸重盐渍化土地复垦利用过程中存在的土壤盐碱、瘠薄等障碍问题,选择重盐渍化区的典型地块作为研究对象,运用地统计学和GIS技术,研究不同土壤盐分离子的空间变异性及其相关关系,并绘制各盐分离子的空间分布图。结果表明:不同深度的土壤盐分离子质量浓度变幅差异较大,最大达到124.34mg·L(-1);各土壤盐分离子质量浓度随着土壤深度的增加而增加,变异系数为10%~100%,属于中等强度变异。偏相关分析结果表明各盐分离子间的相关关系复杂;聚类分析将各盐分离子分为3类:第一类包括TS,σ,TDS,SO_4~(2-),Mg~(2+),K~+,Na~+,Cl~-和Ca~(2+),第二类包括SAR和Cl~-/SO_4~(2-)比值,第三类主要是NO_3~-。各盐分离子的块基比均小于25%,具有强烈的空间相关性,表明盐分离子的空间分布主要受结构性因素影响;空间自相关距离为87.88~215.57m,均大于取样间距40m。克里格(Kriging)插值结果表明:研究区土壤含盐量呈明显的带状分布,土壤含盐量从东北部往西南部逐渐增加,东南部土壤含盐量最高;研究区土壤碱化程度较低,盐渍化类型主要为硫酸盐型。该研究为莱州湾南岸重盐渍化区盐渍土的分区、改良、管理和合理利用提供了理论基础和参考依据。  相似文献   

4.
基于GIS的莱州湾南岸土壤盐渍化特征分析研究   总被引:1,自引:0,他引:1       下载免费PDF全文
运用地统计学,结合GIS技术研究了莱州湾南岸地区土壤含盐量空间变异性.结果表明:土壤含盐量的变异系数除表层和底层属强变异性外,其它均属中等变异强度.整个研究区土壤含盐量较高,盐渍土所占面积较大;除10~20 cm和80~100 cm土层土壤含盐量分布符合球状模型外,其它各层均符合指数模型.研究区不同土层土壤盐分含量具有明显的空间变异性,除60~80 cm和80~100 cm土层土壤含盐量具有强空间相关外性,其它各层均具有中等空间相关性.该研究为莱州湾南岸地区区域规划、农业生产和生态环境维护提供理论依据.  相似文献   

5.
选取莱州湾南岸为典型研究区,系统采集了111个表层土壤样品,测试了土壤的K~+、Na~+、Ca~(2+)、Mg~(2+)、Cl~-、SO_4~(2-)、HCO_3~-、全盐量等8项指标,运用多元统计学和地统计学的方法,揭示了莱州湾南岸的表层土壤盐分离子之间的关系及空间分异规律。研究表明:莱州湾南岸表层土壤盐渍化程度为轻度盐渍化,非盐土占到总面积的51.7%,轻度及中度盐渍土占到总面积的34.3%,重度盐渍土及盐土分布在东北部沿海地区,面积约为148 km~2,占到总面积的14%,并且呈现集中分布态势,盐渍化强弱程度分布格局大致呈现从沿海到内陆逐渐减少的趋势。多元统计分析表明:Na~+与Cl~-、SO_4~(2-)与Ca~(2+)、Mg~(2+)与Cl~-之间呈现显著正相关,Cl~-、Na~+为第1类,Ca~(2+)、SO_4~(2-)、K~+、Mg~(2+)和HCO_3~-为第2类,土壤中盐分离子表现出中等和强烈的空间变异,且盐分离子高值区与海咸水入侵位置基本一致。  相似文献   

6.
土壤盐渍化一直是困扰莱州湾南岸地区农业生产和发展的主要障碍因子。运用GIS和地统计学方法对夏秋两季不同层位土壤含盐量的时空变异特征及其合理采样数量进行了研究,绘制了土壤含盐量的空间分布图。结果表明:随着置信度降低和相对误差的增大,采样数目逐渐减少;各层土壤含盐量具有较大的变异强度;除夏季0~30 cm、30~60 cm和秋季30~60 cm层位具有中等强度空间自相关外,其他各层则表现出强的空间自相关;Kriging插值结果显示不同层位土壤含盐量的空间分布趋势类似,从海边往内陆含盐量逐渐降低,呈带状分布;盐渍化的分布面积较往年有所降低,这对农业生产和发展具有指导意义。  相似文献   

7.
以江苏盐城大丰麋鹿国家级自然保护区第三核心区的土壤为研究对象,采用规则格网法采集土壤样本并测定重要理化指标pH、盐分、有机质、全氮、硝态氮、总碳、有效磷、速效钾,基于克里格插值得到土壤理化指标的空间分布。结果表明:大丰麋鹿野牧区土壤pH、盐分、有机质、全氮、硝态氮、总碳、有效磷、速效钾的平均含量为8.393、6.646g/kg、13.203g/kg、0.748g/kg、6.279 mg/kg、13.955g/kg、10.862mg/kg、486.36mg/kg。土壤pH值变异程度最小,其他均属于中等变异;土壤全盐、总碳、有机质、有效磷和速效钾含量从近海光滩至近岸川新线呈现递减的空间分布规律;土壤pH与其他理化指标存在显著负相关,土壤总碳与全盐、有机质、全氮、有效磷和硝态氮两两间呈显著相关(p0.01);土壤盐度的空间分布与其上覆植被群落的演替规律存在较高的一致性。  相似文献   

8.
黄河三角洲土壤盐分时空变异特征研究   总被引:3,自引:0,他引:3  
环渤海低平原区是中国渤海粮仓的主要构建地,该区域的海拔低,潜水位高,地下水矿化度大导致了土地含盐量高,变幅大。本文运用GIS和地统计学的方法对黄河三角洲土壤含盐量的时空变异特征进行了研究,绘制了土壤含盐量的空间分布图。结果表明:黄河三角洲盐渍土类型以氯化物型盐渍土为主,自2002—2011年盐渍化程度加剧,目前仍处于积盐状态;季节变化表现为土壤盐分秋季高于春季,且由于秋季耕作翻土,土壤盐分的变异程度较大;土壤盐渍化在层位变化则表现为表聚。Kriging插值结果表明该区域的盐分空间分布由河成高地向两侧洼地盐分逐渐增加。本研究的研究结果对于滨海水土资源的开发利用具有重要的指导作用。  相似文献   

9.
莱州湾南岸浅层地下水特征的空间变异性研究   总被引:1,自引:0,他引:1  
以整个莱州湾南岸区域作为研究对象,运用经典统计学和地统计学相结合的方法研究了该区2007-2009年浅层地下水埋深及矿化度的空间变异特征,并绘制了其空间分布图.结果表明:地下水矿化度和埋深在东西和南北两个方向都呈二阶趋势效应,具有强的空间自相关性,说明主要受自然因素影响;kriging插值表明:离海岸线距离越近地下水矿化度越大,地下水埋深表现为西南部较深,而东南部和西北部较浅,地质构造、河流及海水入侵等自然因素作用是形成该空间格局的重要因素.地下水特征的空间结构性和定量化研究对莱州湾南岸地区地下水资源评价和区域水盐迁移调控有着直接的现实意义.  相似文献   

10.
最近50年来莱州湾西-南部淤泥质海岸地貌演变研究   总被引:5,自引:0,他引:5  
在野外考察和前人研究基础上,以1976-2009年间4个时相的MSS/ETM+遥感影像和1958、1984、2002年测量的三期海图为主要数据源,运用3S(RS/GIS/GPS)技术,对最近50年来莱州湾西-南部淤泥质海岸地貌演变进行了研究。结果表明:近50年来,以青坨子为界,莱州湾西、南岸虽均为淤泥质海岸,但其海岸地貌演变存在明显的差异性。具体表现在,莱州湾西岸与南岸的海岸线和等深线变迁时间不同步、变迁幅度差距大、岸线形态不同;莱州湾西岸和南岸地貌类型空间分布不同,转换的趋势、净方向、速率和幅度差异也十分明显以及莱州湾西岸和南岸水下地貌冲淤变化差距悬殊等。莱州湾西海岸的地貌演变与黄河河口-三角洲的地貌变迁基本正相关,变化幅度也较大,后期受到人类活动影响较为明显。海湾南岸的地貌演变受人类活动的影响也日益显著,但其海岸地貌的演变与西岸黄河口-三角洲地貌的剧烈变迁基本无关,莱州湾西岸黄河入海水沙的减少乃至断流对南岸冲於状态变迁也未有显著影响。  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

16.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

17.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

18.
The stages of the development of the basin of the Bransfield Strait   总被引:1,自引:0,他引:1  
The study of the sedimentary body of the Bransfield Strait has made it possible to identify several sedimentary complexes, to construct the first electronic charts for the acoustic basement, and to establish four stages of the evolution of its floor, which updates the previous knowledge about the formation of the strait. At the first stage, there was an increase in tension stresses that were accompanied by the local splits of the continental crust at the periphery of the Antarctic Peninsula. At the second stage, a graben-like structure filled with the Lower stratigraphic complex was formed northward of the Antarctic Peninsula. At the third stage, the continuing processes of extension led to intensive explosive activity of the growing volcanic structures and filling of the graben with sediments of the Middle seismostratigraphic complex. The fourth stage, which has continued until recently, is characterized by quasi-linear localization of the major centers of volcanic activity in the band closer to the South-Shetland Islands and the formation of the Upper seismostratigraphic sedimentary complex. The evolution of the floor of the Bransfield Strait reflects the process of penetration of the American-Antarctic ridge to the continental lithosphere of the Antarctic Peninsula for the last million years.  相似文献   

19.
The first data on the temporal evolution of the slope of the buried depression of the Black Sea are obtained. The sharp change in the rate of the decrease in the slope steepness that occurred in the Late Miocene-Pliocene time reflects a reorientation of the vector of mutual movement and a related intensification of the collision between the Arabian and Eurasian lithospheric plates.  相似文献   

20.
Three mathematical models are considered: a two-dimensional model for calculating the concentration fields of the ecosystem components on the shelf of the Republic of Guinea, a pointwise model for the annual variation of the components, and a two predators-prey model. These models are used to study the effect of hydrodynamic conditions on the state of the shelf ecosystem and for research into the causes which distort the balance between marketable and unmarketable fish.Translated by Mikhail M. Trufanov.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号