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1.
The subdistrict zoning map distinguishes 27 subjects of the Russian Federation, 109 municipal districts, and 142 districts and subdistricts along the latitude line at 53°44′ N in Russia. Among them, soil salinization is observed in 13 subjects of the Russian Federation, 39 municipal districts, and 41 districts and subdistricts. The total length of the transect is 6354 m. The relationship between the distribution of saline soils and climatic parameters has been analyzed in the districts and subdistricts of the subdistrict zoning map. Information about soil salinity has been borrowed from the Soil Salinization Map of Russia (2003) and some regional salinization maps (Khakassia, Barguzin Depression). Climate is the main factor affecting the distribution of soil salinity. Among the analyzed climatic parameters, the Ivanov wetting coefficient (WC) best describes the relationship between climate and soil salinity. The share of saline soils in a district is inversely proportional to the WC value. The degrees of drainage and dissection of the area limit the effect of climate on soil salinity. It is proposed to subdivide the relief into three groups depending on the degree of dissection in order to correct the calculations of relationship between WC and soil salinity. With consideration for relief features, the relationship between soil salinity and WC is represented by a segment of the coordinate plane with WC as the ordinate and the share of saline soils as the abscissa. The segment is limited by two lines corresponding to the maximum and minimum soil salinities at given WC values. The use of the limiting equations allows predicting, with a high probability, the presence and distribution area of saline soils at a given latitude at 0.85 ≥ WC ≥ 0.5.  相似文献   

2.
Eurasian Soil Science - The quantitative and qualitative diversity of the clay fraction (<1 µm) from parent materials (BC and C horizons), albic (suprasolonetzic eluvial SEL)...  相似文献   

3.
Russia has long needed a world-level soil attribute (profile) information database which should become the basis for creating a system of monitoring of the state of soils and for developing measures for their conservation and efficient land use. A unified system of gathering and storing information on soils, which at the same time would be open for general use, is needed. The present work is devoted to problems of the concept and methodology of creating a soil geographic database (SGDB) of Russia. The structure and content of the soil attribute database, underlying which is the concept of representative soils profiles, are given. A list of classifiers for preparing data presentation formats in the SGDB on the basis of existing concepts of soil morphology and classifiers characterizing the main physicochemical properties of soils is developed. The work underlies the creation of an information resource—“Soil-Geographic Database of Russia. Project of the Dokuchaev Soil Science Society”—on the Internet at the address .  相似文献   

4.
区域水土流失地形因子的地图学分析   总被引:5,自引:0,他引:5  
杨勤科  李锐  梁伟 《水土保持研究》2006,13(1):56-58,99
地形是影响区域水土流失的主要因子,基于中小栅格DEM提取的坡度是区域水土流失地形因子的主要指标之一。根据地貌学和地图制图学论文分析和对地形图及其DEM图形分析表明,在一定比例尺范围内(1∶1万~1∶25万),多种比例尺的地形图均能表现区域地形的宏观结构特征;随着DEM分辨率的降低,在DEM上量算得到的坡度不断趋于平缓;由于制图综合不直接影响高程的数值,所以中小栅格DEM表现地面起伏的能力是存在的,只是发生了一定的变形而已。  相似文献   

5.
The results of experimental studies of the postagrogenic transformation of loamy soddy-podzolic soils on the southern slope of the Klin-Dmitrov Moraine Ridge are discussed. A chronosequence of soils (arable soils (cropland)-soils under fallow with meadow vegetation-soils under secondary forests of different ages-soils under a conventionally initial native forest) was examined, and the stages of the postagrogenic transformation of the automorphic soddy-podzolic soils were identified. The differentiation of the former plow horizon into the A1 and A1A2 horizons (according to the differences in the humus content, texture, and acidity) served as the major criterion of the soil transformation. A stage of textural differentiation with clay depletion from the uppermost layer was identified in the soils of the 20- to 60-year-old fallows. The specificity of the postagrogenic transformation of the soils on the slopes was demonstrated. From the methodological point of view, it was important to differentiate between the chronosequences of automorphic and semihydromorphic soils of the leveled interfluves and the soils of the slopes. For this purpose, a series of maps reflecting the history of the land use and the soil cover pattern was analyzed. The cartographic model included the attribute data of the soil surveys, the cartographic sources (a series of historical maps of the land use, topographic maps, remote sensing data, and a digital elevation model), and two base maps: (a) the integral map of the land use and (b) the map of the soil combinations with the separation of the zonal automorphic, semihydromorphic, and erosional soil combinations. This scheme served as a matrix for the organization and analysis of the already available and new materials.  相似文献   

6.
The assessment of the humus content in the mineral soils of Russia based on theoretical, calculated, and expert approaches is given. A review and analysis of the gradations according to the humus content elaborated at the Dokuchaev Soil Science Institute (1977, 1985, 1997, 2001, 2003, and 2004) and by Orlov with coauthors (1978 and 2004) are presented. A theoretical substantiation is given, and an inventory of the soils of Russia qualified by their humus content where the starting point is the minimal humus content is suggested. The objective intervals of the schedule of the humus content are based on the permissible discrepancy of the results obtained by different laboratories. A notion of the global assessment covering a wide spectrum of soils and reflecting the difference between the soil types according to the humus content is introduced, and a differentiated assessment characterizing the differences within the type (subtype) of soils assessed using this parameter is given. The methodological approaches for the determination of the minimally permissible, optimal, and maximally allowable humus contents in the plow horizons are described.  相似文献   

7.
8.
Eurasian Soil Science - An analysis of existing legislation shows that legal norms are established mainly for soils belonging to the category of agricultural land. The orientation of land...  相似文献   

9.
水土保持与土壤质量评价   总被引:1,自引:0,他引:1  
辨析了土壤侵蚀、水土流失和水土保持的概念和内涵。分析了水土保持与土壤质量的关系,认为水土流失会造成土壤的土层薄化、养分循环失衡、劣质化和贫瘠化、以及砂质化和砾质化,反之,土壤质量下降会降低土壤抗冲性和抗蚀性,进一步加剧水土流失,水土保持可以有效地改良和保持土壤质量。综述了土壤质量评价的研究进展,提出水土保持需要从保持土壤质与量的角度,在进一步弄清楚土壤质量演变过程与机理的基础上,尝试选择和建立适合的土壤质量指标与评价方法,并进行土壤质量动态监测与预测预警及对策的研究。  相似文献   

10.
以沙坡头生物结皮(BSC)为研究对象,采用Biolog鉴定系统,通过碳源利用分析、功能多样性分析和聚类分析,对BSC微生物的多样性进行了研究。结果表明:BSC微生物群落代谢的平均颜色变化率(AWCD)在培养初期(0~24h)值很小处于适应期,中后期(24~168 h)AWCD值逐渐增强处于指数期,可能由于监测时间不是足够长,所以稳定期和衰亡期表现得不明显;BSC微生物能够利用羧酸类、聚合物类、碳水化合物类、酚类化合物类、氨基酸类和胺类6类碳源,其中对羧酸类碳源的利用率最高,对胺类碳源的利用率最低;BSC中微生物群落多样性指数为3.99,微生物群落均匀度指数为1.44;指纹聚类分析表明,当聚合水平>8.6时,BSC微生物可分为6类。研究表明,Biolog技术能够简便、快速、有效地反映BSC中的微生物活性及其变化情况。  相似文献   

11.
土壤健康在维持粮食生产、动植物和人类健康方面具有重要作用,是实现农业可持续发展的根本。土壤微生物作为土壤中最具丰富性和多样性的有机生物体,包含细菌、真菌、原生生物和病毒。它们驱动着碳、氮、磷、硫等元素循环过程,并与植物初级生产力和土壤健康息息相关。旱区约占全球陆地表面积的41%,维系了全球约38%以上的人口。西北干旱半干旱区是我国的重要粮食生产后备区,由于其土壤生态系统的复杂性、脆弱性和敏感性导致该地区土壤健康状况相关研究仍缺乏。本文围绕微生物在土壤健康相关生态系统服务如调控作物生长、消减连作障碍、改善水体质量、维持人类健康、缓解气候变化影响和促进碳固存中的贡献,揭示了土壤微生物在维持土壤健康中的关键作用,归纳了土壤微生物作为土壤健康评价指标的发展历程和研究进展。同时介绍了旱区土壤微生物自身特征并总结其对于水分胁迫的响应,归纳了旱区土壤健康研究进展。最后对土壤微生物组与旱区土壤健康研究进行了展望,以期为利用土壤微生物资源维持和改善旱区土壤健康状况提供科学指导。  相似文献   

12.
龙门山地震带土壤细菌多样性的研究   总被引:1,自引:0,他引:1  
《土壤通报》2017,(5):1093-1101
采用16S r DNA变性梯度凝胶电泳(Denaturing Gradient Gel Electrophoresis,DGGE)技术,结合不同土壤样品的理化性质差异,分析龙门山地震带土壤细菌多样性。结果表明,不同的土壤样品其理化性质存在着明显的差异,三种植被类型的土壤(杂木林、竹林和松树林)中,杂木林的土壤pH值和全氮含量最高,竹林最低;而土壤碱解氮、速效磷、速效钾和有机质含量则是杂木林比竹林高,松树林最低。对DGGE优势条带测序分析表明,回收的11个优势条带(条带A~K)中,条带A、C、D、F、G和H属于变形菌门,条带E、J和K属于酸杆菌门,条带B属于放线菌门,条带I属于装甲菌门,变形菌门占细菌总类群的54.55%,说明龙门山地震带土壤优势菌群为变形菌门细菌。细菌群落多样性与土壤理化性质相关性的统计分析结果显示,影响细菌群落多样性的主要环境因子在杂木林土壤中为速效钾(r=0.80,P>0.05),竹林为有机质(r=0.97,P>0.05),松树林则是pH值(r=0.35,P>0.05),说明龙门山地震带不同植被类型土壤中的细菌群落对土壤理化性质的需求不同。由于地震能够破坏土壤结构,改变土壤理化性质,从而导致土壤细菌群落多样性发生改变,因此,研究龙门山地震带土壤细菌多样性为震后灾区重建工作和维持龙门山地震带生态系统的可持续性提供了科学依据。  相似文献   

13.
玉米秸秆还田对盐碱地土壤真菌多样性的影响   总被引:2,自引:0,他引:2  
为揭示盐碱地秸秆还田改良中土壤真菌群落结构及其多样性变化,以未开垦盐碱地(ZH1)、非盐碱连作玉米田(ZH2)和秸秆还田盐碱玉米田(ZH3)为材料,在玉米吐丝期,利用高通量测序技术与相关生物信息学分析结合,研究表层土壤真菌群落丰富度、多样性和群落结构的变化。结果表明,3个处理土壤真菌群落结构和丰度差异大,已知菌属中ZH1的优势属为马拉色菌,ZH2优势属为暗球腔菌属,ZH3优势属为链格孢属。玉米秸秆还田对盐碱地土壤真菌多样性的影响较大,两年玉米秸秆还田盐碱土壤真菌多样性和物种丰度与未开垦盐碱地比较均有所下降。  相似文献   

14.
俄罗斯新土壤分类的研究现状和特点   总被引:1,自引:0,他引:1  
通过与俄罗斯著名土壤学家来访时的交流、结合最新的一些文献记载 ,作者介绍了俄罗斯新土壤分类的研究状况 ,包括土壤分类的原则、方法 ,新土壤系统分类体系的建立、特点与存在的问题。使我国土壤科学工作者对曾是土壤发生分类的发源地的俄罗斯土壤分类研究的最新进展有所了解  相似文献   

15.
《土壤通报》2015,(6):1420-1427
为了研究黑土长期定位试验原状土整体搬迁对土壤细菌群落结构多样性的影响,采用PCR-DGGE及其特异性条带克隆测序的方法,对同为小麦茬的搬迁前2010年和搬迁后2013年土壤细菌群落结构进行研究。结果表明:细菌DGGE图谱中搬迁前后两个土层不同处理所有样品之间具有相似性,进一步对细菌DGGE图谱进行聚类分析可得,细菌群落结构在两个土层各处理中搬迁前后变化不大。再对细菌DGGE图谱主成分分析结果可得,在0~20 cm土层细菌各处理的分布虽然搬迁前和搬迁后产生分异,但在搬迁前后两年中处理间的分布规律相似,在20~40 cm土层搬迁前和搬迁后细菌的MNPK和NPK处理分布规律发生了变化。研究说明,搬迁前和搬迁后土壤中细菌群落结构受到耕作方式、植被类型、土壤肥力等的影响远大于搬迁的扰动影响影响。  相似文献   

16.
灌淤土是含有大量泥沙的黄河水流经长期灌溉而形成,其在宁夏土类中占有一定的比例。为了阐明长期施肥对灌淤土土壤微生物的影响,以宁夏灌淤土土壤肥力监测基地为试验平台,采用平板稀释法和Biolog微生物鉴定系统研究了长期施肥条件下土壤微生物特征的变化。结果表明:长期NP、NK、PK、NPK施肥处理显著降低了土壤细菌数量和土壤微生物总数,细菌数量降低达50%以上。M和1.5NPKM处理增加了土壤放线菌数量,增加的幅度达95%左右,单施氮肥处理显著降低了土壤放线菌数量。NPK和NPKM处理提高了土壤微生物群落对羧酸类、碳水化合物类和酚类碳源的代谢活性,1.5NPKM处理提高了微生物群落对胺类碳源的代谢活性,说明长期的NPK及NPK配合施用有利于土壤微生物活性的提高。施肥处理均不同程度地提高了土壤微生物群落的SHANNON多样性指数但降低了均匀度指数。  相似文献   

17.
严珺  吴纪华 《土壤》2018,50(2):231-238
生物多样性与生态系统功能一直是生态学研究的一个热点。近些年来的研究表明,植物多样性除了影响陆地生态系统地上部分的初级生产力等生态系统功能,还会间接影响地下生物多样性及土壤生态系统过程。本文概述了植物多样性对土壤动物的影响及其主要机制,归纳了植物多样性通过改变输入土壤中的资源数量与资源多样性、微生境结构、土壤环境因子等影响土壤动物的途径。目前关于土壤动物群落对植物多样性的响应仍存在很多问题和争议,本文总结了需要进一步深入研究的方向,特别指出了要加强研究影响植物多样性与土壤动物关系的生物与非生物因子、后续的生态效应和反馈、不同机制和途径的贡献定量化等。  相似文献   

18.
采用分离培养和生理生化试验等方法,对呼伦贝尔草甸草原优势种群羊草和贝加尔针茅根际土壤微生物多样性及优势菌株进行了研究。结果表明,3类土壤样本微生物总数由高到低依次为:羊草>贝加尔针茅>对照组,但差异不显著(p>0.05);样地中呈现:细菌总数>放线菌总数>真菌总数,细菌与放线菌和真菌均呈显著差异(p<0.01)。在羊草根际土壤中分离到的优势菌株为细菌7个属36株,放线菌4个属21株,真菌3个属17株。  相似文献   

19.
气候对旱地紫色土微生物功能多样性的长期影响   总被引:1,自引:0,他引:1  
李云  孙波  李忠佩 《土壤》2009,41(2):230-235
研究了暖温带和中亚热带气候对紫色土的理化性质、微生物活性及其多样性的长期影响.将安徽休宁的紫色土分别放置在暖温带的封丘和中亚热带的鹰潭,18年的旱作定位试验结果表明,中亚热带紫色土的pH、全N含量、NO3--N含量和有效P含量显著低于暖温带紫色土;中亚热带气候条件下紫色土微生物整体活性高于暖温带;中亚热带气候条件下紫色土微生物对羧酸和糖类利用较多,而在暖温带气候条件下紫色土微生物对氨基酸和胺类的利用能力较高.说明中亚热带气候条件促进了紫色土微生物对含C化合物的利用,而暖温带气候条件促进了紫色土微生物对含N化合物的利用.  相似文献   

20.
蚯蚓粪对温室黑土土壤酶活性及细菌多样性的影响   总被引:1,自引:0,他引:1  
《土壤通报》2014,(4):835-840
试验研究了蚯蚓粪对黑土土壤酶活性、细菌数量及多样性的影响。共设5个处理:处理1,对照(CK),不施肥;处理2,蚯蚓粪7.5 t hm-2;处理3,蚯蚓粪15 t hm-2;处理4,蚯蚓粪30 t hm-2;处理5,蚯蚓粪60 t hm-2。结果表明,蚯蚓粪对土壤过氧化氢酶、脲酶、蔗糖酶和磷酸酶活性有促进作用,但因酶类型的不同略有差异;随着蚯蚓粪施用量的增加,土壤细菌数量呈现先升高后降低的趋势,而土壤细菌群落多样性表现为递增趋势。各处理对土壤细菌丰富度和多样性指数的影响显著高于对照,但各处理间均匀度指数无差异。聚类分析表明,处理3(蚯蚓粪15 t hm-2)与处理4(蚯蚓粪30 t hm-2)的土壤细菌DGGE图谱相似性达93.8%,并聚成一簇,说明处理3土壤细菌种类与处理4相似性最高,处理3与处理4对土壤细菌多样性指数与均匀度指数影响均无显著差异,但条带数显著增加;处理4与处理5(蚯蚓粪60 t hm-2)相似性达到78.1%,与处理1和处理2(7.5 t hm-2)的相似性只有57.3%,说明蚯蚓粪的施入导致土壤有益微生物种类和数量增加,提高土壤细菌多样性,从而使土壤酶活增强。  相似文献   

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