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1.
太白山北坡土壤的粘土矿物   总被引:1,自引:0,他引:1  
陈俊卿 《土壤学报》1982,19(3):273-282
太白山位于陕西省西部,绝顶海拔近4000米,是秦岭山脉的主峰,属于我国西北中部地区最高名山之一。地理位置约为北纬33.9-34.15度,东经107.4-108.0度。由于秦岭的屏障使潮湿的海洋气团不易深入西北,同时也阻挡了北方的寒潮不致长驱南下,所以秦岭已成为自然地理上划分我国东部南北的重要界线。太白山的气候具有南温带的温和气候和北亚热带的温暖气候特点,属于温带和亚热带过渡性地带。  相似文献   

2.
We studied the relationship between plant and soil animal communities by geostatistical analysis in a piedmont forest close to Novorossiysk (Southern Russia). Vegetation on the slope of a hill was an oak-ash-hornbeam forest, while the vegetation on the foot of the hill was a maple-ash-hornbeam forest. Two plots were studied each including both slope and foot habitats. On every plot samples collected formed a grid of 10 × 5 units with a 5 m distance between them. Soil macroinvertebrates were hand-sorted from the samples, and several soil parameters (soil, pebble, and litter mass, soil moisture) were measured.The analysis did not reveal coincidence between the boundaries of plant and soil animal communities on the bend of the hill. Soil animal communities of the plots were dominated by woodlice, diplopods, and insect larvae, reaching an abundance of 680–990 individuals m2 throughout the plots. Number of taxonomic groups per sample and overall animal abundance in the bend were the highest in both plots, whilst these parameters on the slope were the lowest. Variograms and maps of spatial distribution indicated that the boundary between soil animal communities was situated further up on the slope than the vegetation boundary. The size of the animal community was smaller than the size of plots sampled, what probably explained the lack of coincidence between the boundaries. There was a significant correlation between distribution of litter mass and parameters of soil animal communities, which was modulated by depth of soil layer and soil moisture. Soil parameters were more important for explaining boundaries between soil animal communities than plant communities in the forest considered.  相似文献   

3.
本文研究结果表明:(1)神农架垂直带土壤矿物的风化脱硅作用较弱,粘土矿物以2:1型矿物为主,1:1型高岭含量很少。(2)随海拔升高,矿物的淋溶脱钾和层间羟基铝化作用增强,低海拔土壤的2:1型矿物以水云母为主,高海拔土壤以1.4nm矿物为主,其中1.4nm过渡矿物相对增多。(3)土壤的络合态铁、铝和非晶形铁,铝含量随海拔升高明显增大。(4)土壤的可变电荷量,阴离子交换量,交换性酸和铝饱和度等均随海拔  相似文献   

4.
Data on the taxonomic and trophic composition, population density, and biomass of invertebrates in the soils of the main mountain vegetation zones of the Khibiny Mountains—taiga, subalpine, and alpine—are obtained. The degree of similarity between soil faunal complexes in different vegetation zones within the studied slope is higher than that between zonal biocenoses of Murmansk oblast. The mountain tundra zone differs from the zonal tundra in a higher population density and taxonomic diversity of invertebrates, which are similar to those in the northern taiga podzols. At the same time, invertebrate complexes in the mountain taiga zone are poorer than those in the zonal plain taiga soils. The analysis of invertebrate taxa present in all the studied mountain vegetation zones demonstrates similar effects of the altitudinal and latitudinal zonality on the species composition of invertebrates. A conclusion is made about a higher functional activity of saprotrophs in the high-humus soils enriched in biogenic elements of the Khibiny Mountains in comparison with the functional activity of saprotrophs in the zonal plain podzols.  相似文献   

5.
山地森林土壤枯枝落叶层结构和功能的研究   总被引:33,自引:0,他引:33  
本试验设置在卧龙自然保护区1200-4300m海拔高度不同生物气候带的森林类型下.五处试验林地是:1.常绿阔叶林下的山地黄壤;2.次生落叶阔叶林下的山地棕壤;3.针阔混交林下的山地暗棕壤;4.暗针叶林下的山地棕色暗针叶林土;5.高山草甸植被下的高山草甸土.通过1981-1984年进行定位观测和试验研究,其结果阐明了该林区森林枯枝落叶层的构型、贮量及其化学、物理性质和灰分元素组成等;并探讨了森林枯枝落叶层在森林土壤生态系统中对水源涵养、养分供应、促进生物活动强度和土壤发育等方面的功能.  相似文献   

6.
在图们江流域生态调查研究中,通过实地调查与观测,提出了对土壤生态系统功能进行评价的客观标准,并制定出地形条件影响土壤生态功能的变量指标。研究结果表明:1.图们江流域土壤生态功能随海拔高度的增加而减弱。其生态功能强弱的垂直分异系列在丘陵山地中表现为:山地暗棕壤>丘陵暗棕壤>山地棕色针叶林土>山地苔原土;在台地中表现为:台地白浆土>高台地白浆土>低台地白浆土。2.图们江流域,地形直接控制着当地气候和生物,尤其制约着水、热条件的垂直变化。因而它就成了限制土壤生态功能的主要因素。而植被的破坏与水土流失则加剧了土壤生态功能的退化。3.土壤动物类群和数量的变化是衡量土壤生态功能强弱、进化与退化的重要指标。  相似文献   

7.
江西九江地区森林土壤有机碳含量及其影响因素   总被引:3,自引:0,他引:3  
为阐明地处亚热带北缘的九江地区森林土壤有机碳水平及其主要影响因素,在庐山南、北坡分别选择6个和5个不同海拔点的典型植被群落,并在九江市丘陵分别选择7种典型林分,分层采集土样,测定了有机碳含量。结果表明:北坡森林表层土壤(0~20 cm)有机碳含量处于18.47~33.92 g kg-1之间,南坡为19.59~34.43 g kg-1。在0~20 cm土层,油茶林有机碳含量(17.69±0.85 g kg-1)最低,针阔混交林最高(27.64±0.57 g kg-1);在20~40 cm土层,毛竹林有机碳含量(14.08±1.21 g kg-1)最低,针阔混交林最高(20.19±0.40 g kg-1)。海拔、海拔与坡向的交互作用和植被类型显著影响着森林土壤有机碳,坡向没有关系。  相似文献   

8.
阳海清 《土壤学报》1996,33(2):166-174
根据鄂西山地的自然成土条件,分析了酸性棕壤、灰棕壤诊断层和诊断特性,主要理化性质和粘土矿物组成,结果表明:酸性棕壤和灰棕壤同属于亚热带中山上部或亚高山中上部冷湿条件下形成的森林土壤。其理化性质与我国北方同类土壤又有较大差别。  相似文献   

9.
In many terrestrial ecosystems, soil parameters usually regulate the distribution of earthworm communities. In alluvial ecosystems, few studies have investigated the impact of periodic floods and alluvium deposition on soil fauna. In this context, we assumed that earthworm communities may vary depending on altitude (alpine, subalpine, mountain and hill levels), forest successional stage (post-pioneer to mature forests) and some soil parameters. Our results demonstrated that the composition of earthworm communities differed depending on altitudinal gradients. No earthworm was found at the alpine level while maximum density and biomass were observed at the hill level mainly due to the contribution of anecic species. A total of 27 species and subspecies were found over the three sampling sites, and Lumbricus moliboeus was discovered for the first time in carbonated soils. Soil texture had a major effect on epigeics that were often associated with coarse sandy texture in contrast to anecics which preferred deep soils and mature forest stages, which in combination provided the highest carbon content and the finest soil texture. In our study, carbonated fluviosols (Fluvisols according to the World Reference Base) were recorded; fluviosols typiques with well-structured A layers were generally found in mature or intermediate forest stages while most of fluviosols juveniles with heterogeneous texture were observed principally in post-pioneer forests. We conclude that in alluvial ecosystems, earthworm communities were highly dependent first on soil parameters, then altitude and to a lesser extent forest successional stages. Changes in earthworm communities tend to reflect a gradient of alluvial dynamics thus reinforcing the potential role of earthworms as bioindicators in natural and/or semi natural alluvial ecosystems.  相似文献   

10.
The study of soil cover in the mountainous forest-steppe on the southwestern macroslope of Khentei Ridge has shown that the spatial distribution of soils is controlled by the ruggedness of topography, slope aspects, geocryological conditions, and the thickness of loose deposits. The soils belong to the orders of lithozems and organo-accumulative soils (Mollic Leptosols) of the postlithogenic trunk of pedogenesis. Dark-humus and mucky–dark-humus horizons of the organic matter accumulation are characteristic features of these soils. The investigated area is differentiated according to the soil moistening conditions on the slopes of different aspects. Favorable growth conditions for dwarf birch and Siberian larch at the southern boundary of the boreal forests in Mongolia are explained by the relatively high moistening of mucky–darkhumus lithozems and mucky–dark-humus soils developed on windward northern slopes and on mountain terraces in places of the local snow accumulation by wind. An important role in preservation of forest vegetation belongs to permafrost in small cirque-like depressions.  相似文献   

11.
In Costa Rica, the Maquenque National Wildlife Refuge (MNWLR) contains a unique habitat gradient ranging from primary old growth forests, grasslands, pastures, to various ages of secondary forests. Within these primary old growth forests are extremely dense naturally occurring Bromelia pinguin (Bromeliaceae) patches that often grow with densities up to 2 plants per square meter. A previous study found that anti-fungal activity of this particular plant appears to be altering the fungal community in soils adjacent to these plants. No work has been previously conducted on the possible effects of this plant community on soil faunal communities and if seasonality contributes to changes in soil invertebrate populations along a moisture gradient. Thus, a study was conducted to assess the effects of this specialized plant community on soil invertebrates with respect to season, and if these changes in soil fauna guild structure could prove to be valid candidates as indicators of ecosystem condition with changes in precipitation. In addition, a meta-analysis was done to determine how the bromeliad-associated soil invertebrate communities differ from those in adjacent primary forest soils. Therefore, comparisons were determined from previous primary forest soil invertebrate environmental DNA (eDNA) to the current wet season bromeliad soil invertebrate eDNA. Roche 454 pyro-sequencing was conducted on the 650 bp fragment of the cytochrome oxidase subunit I (COI) gene of invertebrates to obtain and characterize soil invertebrate sequence composition. To determine relationships among soil fauna guilds across seasons, relative abundance of the sequences were calculated, and used in conjunction with EcoSim niche overlap and co-occurrence values. From the bromeliad seasonal soil fauna eDNA study, it appears certain invertebrate guilds are driven by moisture as indicated by fluctuations in relative abundance of each invertebrate guild across seasons in bromeliad patch soils, as well as indicated by EcoSim niche overlap values. In particular, Guilds 1, 4, and 5, should warrant further investigation as indicators of habitat condition. The meta-analysis showed that a naturally occurring modified environment (the bromeliad patches), can result in differences in relative abundance and partitioning of a limited resource between invertebrate guild structure. Those guilds associated with microbivorous and complex decomposition activities (i.e. Guilds 3 and 4), are more abundant in primary forest soils than bromeliad patch soils and could potentially used for bioindicators of habitat perturbations.  相似文献   

12.
This study investigated the responses of soil animal communities, soil functioning and humus forms to forest dynamics and solar radiation. We examined changes in invertebrate communities and soil features in two subalpine spruce forests (Eastern Italian Alps, Trento) growing on a calcareous bedrock, with different sun exposures (north and south), each forming a chronosequence of three developmental phases: clearing, regeneration stand (25-year-old trees) and mature stand (170-year-old trees). Our results indicate that the two forest sites differed in solar energy input, soil chemical properties and the relationships between forest dynamics and animal communities. In the north-facing site, soil fauna communities were very similar in the three forest developmental phases. Conversely, in the south-facing site, the composition of invertebrate communities and the diversity of zoological groups varied greatly among developmental phases. The highest abundance of total invertebrates, and mites in particular, occurred in the south-facing mature stands while the south-facing regeneration stand was characterised by higher densities of Collembola, Chilopoda, Symphyla, Protura and Aranea. The structure of communities in clearings was the same as in regeneration stands but with lower invertebrate abundance. Humus forms and soil features changed with developmental phases in both the south- and north-facing sites, although variations were more pronounced in the southern exposure. Mature stands were characterised by high levels of soil organic carbon and nitrogen, C/N values and low pH, the clearings and regeneration stands being characterised by a greater release of mineral nitrogen. The diversity of zoological groups (Shannon–Wiener index) was linearly correlated to soil pH, Humus Index, the amount of organic carbon and the species richness of herbaceous plants. Our results about the composition and the diversity of invertebrate communities are consistent with the observations of other authors studying south-exposed forests growing on different bedrock types, indicating that such relationships are widespread. The higher densities of invertebrates in the south-facing site may be attributed to higher solar radiation, and the positive correlation observed between total soil fauna abundance and solar energy supports the “more individuals” hypothesis that assumes a positive relationship between the number of individuals and energy availability. Possible ways by which forest dynamics control soil invertebrate communities are discussed.  相似文献   

13.
左家自然保护区大型土壤动物与土壤因子关系研究   总被引:2,自引:0,他引:2  
从生态序列的角度研究了左家自然保护区微地貌中大型土壤动物群落的分布格局,同时考虑到土壤因子对大型土壤动物的综合作用,从小尺度上探讨大型土壤动物群落与土壤因子的关系。研究结果表明,凋落物的种类和数量差异对大型土壤动物的分布影响明显,阴坡和阳坡的四个生境坡谷、坡麓、坡中、坡顶植被差异较小,土壤因子是研究区大型土壤动物序列分布的一个重要影响因子。微地貌条件下,土壤有机质、土壤含水率、pH、全氮、全磷变化趋势接近,土壤温度与土壤含水率、pH、土壤有机质、全氮和全磷这5个指标变化趋势相反,土壤有机质、土壤含水率、pH、全氮、全磷和土壤温度这6个指标对研究区主要的大型土壤动物类群的分布有重要的影响。  相似文献   

14.
The study of three types of forest soils has shown virtually no reliable relationships between the distribution of large soil invertebrates and the soil parameters (the stone content, pH, litter thickness, etc.) when the sample area has a size of 76 cm2. However, an increase in the size of the observation plots by two to four times (depending on the particular soil type) makes it possible to find statistically significant coefficients of correlation between the studied parameters. Thus, the size of the sample area influences our assessment of the relationships between the abundance of large invertebrates and the soil parameters. In each of the studied types of forest soils, the heterogeneity of the soil structure is manifested at different scales. A correct forecast of the effect of the factors of the soil on the population of large invertebrates depends on the spatial distribution of these factors.  相似文献   

15.
Phospholipid fatty acid (PLFA) patterns were used to describe the composition of the soil microbial communities under 12 natural forest stands including oak and beech, spruce-fir-beech, floodplain and pine forests. In addition to the quantification of total PLFAs, soil microbial biomass was measured by substrate-induced respiration and chloroform fumigation-extraction. The forest stands possess natural vegetation, representing an expression of the natural site factors, and we hypothesised that each forest type would support a specific soil microbial community. Principal component analysis (PCA) of PLFA patterns revealed that the microbial communities were compositionally distinct in the floodplain and pine forests, comprising azonal forest types, and were more similar in the oak, beech and spruce-fir-beech forests, which represent the zonal vegetation types of the region. In the nutrient-rich floodplain forests, the fatty acids 16:1ω5, 17:0cy, a15:0 and a17:0 were the most prevalent and soil pH seemed to be responsible for the discrimination of the soil microbial communities against those of the zonal forest types. The pine forest soils were set apart from the other forest soils by a higher abundance of PLFA 18:2ω6,9, which is typical of fungi and may also indicate ectomycorrhizal fungi associated with pine trees, and high amounts of PLFA 10Me18:0, which is common in actinomycetes. These findings suggest that the occurrence of azonal forest types at sites with specific soil conditions is accompanied by the development of specific soil microbial communities. The study provides information on the microbial communities in undisturbed forest soils which may facilitate interpretation of data derived from managed or even damaged or degraded forests.  相似文献   

16.
The soil cover patterns in the subtaiga landscapes on the northern spurs of the Tsagan-Daban Ridge in the Selenga Mountains have been studied. Gray-humus lithozems and bedrock outcrops are typical of the steep south-facing slopes under herbaceous pine forests. Soddy iron-illuvial podburs are formed under forest vegetation on gentle slopes of northern and western aspects with a thick mantle of loose colluvial deposits. Dark-humus metamorphic soils occur on the slopes of western and northwestern aspects below 700 m a.s.l. under secondary forb-grassy communities that replaced the initial herbaceous pine forests. Windblown hollows (yardangs) are occupied by humus psammozems under steppe pine forests. The morphological and physicochemical characteristics of these soils are discussed in the paper.  相似文献   

17.
The Changbai Mountains, located in northeastern China, show clear vertical zonation of vegetation types. Six different habitats, namely Pinus koraiensis mixed broad-leaved forest, Pinus koraiensis-Picea forest, spruce-fir forest, Betula ermanii forest, alpine meadow and alpine semi-desert, at elevations ranging from 780 to 2 480 m, covering almost all ecosystems on the north slope of the Changbai Mountains, were investigated to determine: i) whether or not the community composition of soil mesofauna varied significantly at different elevations; ii) if different soil mesofauna groups would respond differently to elevation and iii) which factors influenced the spatial distribution of soil mesofauna along elevation. Soil mesofauna were collected from each habitat in spring (May), summer (July) and autumn (September) of 2009. The soil mesofauna communities were comprised of at least 44 groups and were dominated by Acari and Collembola, followed by Coleoptera, Diptera larvae and Enchytraeidae. The composition, diversity and abundance of soil mesofauna varied among the six habitats. Meanwhile, significant seasonal variations were observed in the composition, abundance and diversity of the soil mesofauna in each habitat. The taxonomic richness and Shannon index were affected by elevation and soil properties, while the abundance was only significantly affected by soil properties. With regard to taxa, the habitats and seasons had significant effects on almost all the abundances of the major taxonomic groups. The abundance of more taxonomic groups was significantly influenced by the soil properties, while those of Geophilomorpha, Araneae and other taxa were affected by elevation. It is concluded that the composition and spatial distribution of the soil mesofauna varied along the elevation gradient on the north slope of the Changbai Mountains, which might be largely related to the variations of the plant community, soil properties and climate change resulting from the elevation gradient.  相似文献   

18.
Ewa Nowak   《Pedobiologia》2001,45(6):497-508
The study was conducted in two successional series: natural on mesotrophic soils (a meadow, two birch woods and a mixed coniferous forest), and human-made on sandy soils (old field, birch plantation and pine forest). In both these series species richness and diversity of enchytraeid communities decreased with advancing succession. In the first two successional stages, enchytraeid communities showed a high degree of similarity (the meadow and 30-year-old birch thicket, ore the old field and 10-year-old birch plantation). Variation in soil in the same plant communities cause differences in animal communities. The abundance of enchytraeids varied from 14 to 51 × 103 m−2 individuals. In the majority of habitats C. sphagnetorum was the dominant species. Soil pH showed a positive correlation with species diversity and negative with number of C. sphagnetorum. The body size of this species was small at low pH (presumably as a result of frequent reproduction). It is suggested that the way of reproduction of the dominant species could confer a competitive advantage, thereby accounting for the simplification of enchytraeid communities in later stages of succession.  相似文献   

19.
Soil organic matter composition and biochemical properties were determined in mountain calcimorphic Mediterranean soils under different vegetation (cultivated soils, secondary bush, high mountain bush, juniper, evergreen oak and pine) to assess the impact of soil use on the size and activity of microbial communities. Our results indicated that clearing forest leads to a general decline in the performance of soil organic carbon sequestration and associated enzymatic activities. However, when soil enzymatic activities (dehydrogenase, catalase, phosphodiesterase, β‐glucosidase, urease and casein‐protease) were expressed as ratios to total organic carbon (specific activities), a conspicuous increase in their activities was observed in cleared soils as compared with forest soils, suggesting enhanced hydrolytic potential in the former. In addition, the negative correlation observed between qCO2 (metabolic quotient) and water retention at ?1500 kPa, could be interpreted as an adaptive strategy against low soil moisture by microbial communities in cleared soils. This indicates the importance of describing soil quality in terms of long‐term soil organic C sequestration and/or resistance of the organic matter to microbial transformation. These features were reflected in the visible and infrared spectra of humic acids, which suggested humification mechanisms involving mainly an alteration of plant macromolecules with poor incorporation of characteristic microbial metabolites in the forest soils whereas the opposite effect was observed in cleared soils.  相似文献   

20.
以黄顶菊(Flaveria bidentis)入侵的林地、荒地和沟渠作为调查样地,探讨黄顶菊凋落物对土壤无脊椎动物群落的影响。利用环刀进行取样,3种生境共捕获土壤无脊椎动物54 315头,隶属2门10纲17目。3种生境的优势类群皆为蜱螨目和弹尾目,其余类群的相对多度较小。黄顶菊凋落物能够为土壤无脊椎动物提供栖息地与食物来源,进而影响其群落结构及多样性,该影响与黄顶菊自身群体的生长状况有关,在长势较弱的林地生境影响较小,而在长势较强的荒地和沟渠生境影响较大。综上所述,黄顶菊入侵3种生境后,植株及其凋落物能为优势类群提供更好的栖息地和隐蔽所,并通过改变表层腐殖土的主要养分含量,引起土壤无脊椎动物多样性的升高,且土壤无脊椎动物在凋落物层中多样性呈自上而下的升高趋势。  相似文献   

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