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1.
黄土丘陵区林-草景观边界土壤表层大型动物多样性研究   总被引:1,自引:0,他引:1  
文章通过对黄土高原丘陵区刺槐林-草地复合系统景观边界上3种景观位置的土壤表层大型动物调查、分析,结果表明:复合系统共有大型土壤动物16类,隶属于3门6纲;林缘处是土壤表层大型动物多样性最高的地方,这里土壤动物群落较复杂,类群数较多,分布均匀;草地是土壤表层大型动物多样性最低的地方,这里土壤动物群落较单一,土壤动物类群数偏少,个体数偏多,分布的均匀性较差,优势类群表现突出;林地的土壤表层大型动物多样性介于二者之间。林缘与林地内土壤动物的分布特征相似性较大,林缘与草地内土壤动物的分布特征相似性较小。  相似文献   

2.
为了揭示土壤动物在紫色土壤改良和发育进程中的地位和作用,对衡阳地区紫色土壤7种生境中的土壤动物进行了调查.探讨了7种生境中土壤动物群落结构特征,并进行了多样性、均匀性及相似性分析.结果表明:共获得土壤动物2994只,隶属于4门8纲30目,其中优势类群2类,常见类群12类.  相似文献   

3.
汶川地震次生灾害对土壤动物群落的影响   总被引:2,自引:0,他引:2  
为了查明地震次生灾害对土壤动物的影响,2008年11月在四川彭州银厂沟内分别选取泥石流、滑坡2个次生灾害区样地和2个柳杉林对照样地,对4个样地的土壤动物群落进行调查.结果表明:2个次生灾害区均未发现大型土壤动物,对照区共有大型土壤动物196只,隶属3门7纲17目36类(科),平均密度为65.34个·m-2;次生灾害区共调查到中小型土壤动物232只,隶属3门4纲6目26类(科),平均密度为3 222.22个·m-2;对照区共有中小型土壤动物2 747只,隶属3门7纲9目64类(科),平均密度38 152.78个·m-2;次生灾害区中小型土壤动的类群数、个体密度、多样性指数H和丰富度指数D均显著低于对照区(P<0.01),均匀度指数E显著高于对照区(P<0.01);群落多样性的变化主要是因部分稀有类群的消失和群落密度的下降;与对照区相比,次生灾害区中小型土壤动物群落的湿生性种类的个体百分比下降,旱生及中生性种类的个体百分比增加;次生灾害区与对照区间的群落相似性低于2组样地内部不同样地间的相似性.地震次生灾害对土壤动物,尤其是大型土壤动物的群落结构及多样性有强烈的干扰作用.  相似文献   

4.
保定市不同绿地类型土壤动物群落结构特征研究   总被引:6,自引:0,他引:6  
2006年5~10月对保定市4种城市绿地生境中的土壤动物群落进行了调查研究,共采获到土壤动物1462只,隶属2门8纲14目。其中优势类群为蜱螨目、弹尾目和膜翅目,常见类群为颤蚓目、蜘蛛目、双尾目和鞘翅目幼虫,其余类群为稀有类群。4种绿地类型的土壤动物种类组成极为相似。从单位面积土壤动物数量看,表现为苗圃绿地〉公园绿地〉道路绿地〉防护绿地。从土壤动物群落数量的垂直分布来看,随着土壤层次的加深而递减,0~5 cm土壤层数量最大,有明显的表聚现象。土壤动物的多样性与均匀度指数呈正相关,与优势度呈负相关。  相似文献   

5.
采用手拣法对果园土壤动物进行分离提取,旨在了解果园土壤动物群落结构多样性与季节变化。结果表明,土壤动物自身的生长生理特点和自然环境条件决定了土壤动物的个体密度和类群数的季节差异。单向蚓目、膜翅目两类的数目最高,是果园土壤动物群落的优势种群;蜘蛛目、鞘翅目、半翅目、鳞翅目、双尾目5类次之;它们的个体密度呈现出波动的形式,5月、6月呈现上升的趋势,7月达到了个体密度最大值,9月、10月又呈现下降的趋势。这种波动形式的变化充分说明了季节的变化对果园土壤动物群落结构的影响。  相似文献   

6.
2012年6月对茂兰喀斯特2种森林湿地土壤动物群落进行了调查。结果共获得土壤动物6 909只,分别隶属于3门11纲31目,其中优势类群为真螨目、蜘蛛目、鞘翅目、膜翅目,占总捕获量的58.72%;常见类群17类,稀有类群10类。多样性分析表明,土壤动物群落多样性指数和均匀度指数为板寨溶洞湿地最大,类群数和个体数最大为陇用沼泽湿地;土壤动物功能类群在数量比例关系表现为腐食性土壤动物最多,其次为植食性土壤动物,捕食性土壤动物最低。  相似文献   

7.
通过萌发实验的方法对兰坪铅锌矿区3种尾矿恢复初期的植物群落(以下简称恢复群落,包括魁蒿群落、马桑灌丛、草地早熟禾人工草地)和1种对照群落(云南松林)土壤种子库的季节变化进行比较研究,结果显示:各群落雨季末期土壤种子库储量均高于旱季末期,其中,3种恢复群落种子库储量季节变化显著(p0.05),对照群落季节变化不显著(p0.05);各群落雨季末期土壤种子库物种多样性均高于旱季末期,3种恢复群落物种多样性均低于相应对照群落;各群落土壤种子的垂直分布均为上层中层下层;各群落土壤种子库优势种季节变化均较大,一些优势种仅出现于雨季末期或旱季末期;3种恢复群落2个季节土壤种子库的相似性指数高于对照群落。  相似文献   

8.
以民勤连古城国家级自然保护区4个不同生境为研究对象,于6月对荒漠土壤动物进行了收集,共收集获得12个类群2349只土壤动物个体,优势类群整体以鞘翅目、蚁科、蜘蛛类群为主。探讨了荒漠生态系统土壤动物的群落组成、多样性及其群落相似性。结果表明:植被类型和生境土壤环境条件是决定土壤动物群落组成、多样性、相似性的重要因素。试验结果可为荒漠生态系统土壤动物生态学的研究打下一些基础,为保护区的健康评价提供一定的科学支撑。  相似文献   

9.
2006~2007年,对济南市龙洞地区进行了土壤动物多样性调查研究。在调查地区4个样地共获得各类土壤动物样本5178头,隶属于4门8纲,共16个类群。通过分析该地区土壤动物的群落组成、多样性及水平分布和季节动态特点,结果表明:蜱螨目、弹尾目、线虫纲属于该地区的优势类群;倍足纲为常见类群;鳞翅目、鞘翅目、双尾目等12个类群为稀有类群。不同样地中土壤动物的种类和个体数量都有一定的差异,地温和土壤含水量对土壤动物的数量影响较大。同时也对各样地的土壤动物多样性指数H'、优势度指数C和均匀度指数E进行了分析。各样地群落间相似性系数在0.44~0.79之间。  相似文献   

10.
【目的】比较研究塞罕坝地区华北落叶松人工林间伐和混交改造对大型土壤动物群落组成和多样性的影响,为实现华北落叶松人工林质量精准提升和可持续利用提供理论依据和技术支撑。【方法】以塞罕坝机械林场未经营的华北落叶松人工林(CK)、抚育间伐后的华北落叶松人工林(TH)和引入阔叶树的华北落叶松白桦混交林(M)为对象,于2014年5—9月,利用手拣法调查大型土壤动物群落,研究不同经营措施林分内土壤动物的结构组成、空间分布、多样性和功能群组成的差异及其影响因素。【结果】共获得大型土壤动物55类1 405头,隶属2门4纲12目,优势类群为正蚓目、叶甲科幼虫、象甲科幼虫。总体上,经间伐和混交改造后华北落叶松人工林内大型土壤动物的类群数显著高于未经营的对照林分(P005),TH内土壤动物密度亦显著高于CK(P005)。不同经营措施林分大型土壤动物类群数均表现为沿土壤剖面位置上升逐渐增加的趋势,且M和TH凋落物层土壤动物类群数及0~10 cm土层土壤动物密度显著高于CK(P005)。间伐和混交改造后,土壤动物群落各多样性指数均有提高,其中M的Shannon-Wiener多样性指数(H)显著高于CK(P005)。各功能群中,植食性土壤动物所占比例(4719%)最高,其次为腐食性土壤动物(3331%);捕食性(19类)和植食性(18类)土壤动物的类群数居多;多因素方差分析显示,经营措施、土层和时间均对大型土壤动物功能群组成和结构影响显著(P005),其中间伐和混交改造均可显著提高植食性土壤动物的类群数。冗余度分析(RDA)显示,凋落物全碳含量(P=003)和C/N(P=008)对凋落物层大型土壤动物分布影响显著;而土壤含水量(P=0008)、pH(P=0012)和土壤密度(P=0062)对土壤层大型土壤动物分布影响显著。【结论】塞罕坝华北落叶松人工林经间伐和混交改造后,林分结构和微环境的改善可提高大型土壤动物的种类、数量和多样性水平,尤其是部分功能群种类增加可能更有利于凋落物早期的粉碎和分解。  相似文献   

11.
Agroforestry systems are widely practiced in tropical forests to recover degraded and deforested areas and also to balance the global carbon budget. However, our understanding of difference in soil respiration rates between agroforestry and natural forest systems is very limited. This study compared the seasonal variations in soil respiration rates in relation to fine root biomass, microbial biomass, and soil organic carbon between a secondary forest and two agroforestry systems dominated by Gmelina arborea and Dipterocarps in the Philippines during the dry and the wet seasons. The secondary forest had significantly higher (p < 0.05) soil respiration rate, fine root biomass and soil organic matter than the agroforestry systems in the dry season. However, in the wet season, soil respiration and soil organic matter in the G. arborea dominated agroforestry system were as high as in the secondary forest. Whereas soil respiration was generally higher in the wet than in the dry season, there were no differences in fine root biomass, microbial biomass and soil organic matter between the two seasons. Soil respiration rate correlated positively and significantly with fine root biomass, microbial biomass, and soil organic C in all three sites. The results of this study indicate, to some degree, that different land use management practices have different effects on fine root biomass, microbial biomass and soil organic C which may affect soil respiration as well. Therefore, when introducing agroforestry system, a proper choice of species and management techniques which are similar to natural forest is recommended.  相似文献   

12.
Domestic livestock grazing and firewood extraction are chronic and pervasive disturbances in dry secondary forest that reduce diversity and modify composition. Exclosure of such disturbances may allow the reestablishment of original diversity. To investigate potential vegetation recovery following 30 years of perturbation, seed rain was evaluated monthly during 3 years in 96 0.78 m2 seed traps located in eight exclosures established in 2006 in a species-poor secondary dry forest in central Mexico. Twelve additional seed traps were located outside the exclosures in 2010 for comparison purposes. Baseline diversity of seed sources (trees, ?5 cm DBH) was recorded to compare standing tree composition with seed rain. Also, baseline diversity of potential primary (birds) and secondary (ants) dispersal vectors were registered to infer current plant-animal interactions. Total seed rain over 3 years within the exclosures comprised 180,375 seeds from 61 woody species, an average of 1.12 seeds/m2/month. Half of these species (31) and 95% of the seeds falling within the exclosures belonged to trees typical of perturbed sites. Sixty percent of all recorded seeds belonged to an early-successional, bird-dispersed shrub (Hamelia patens Jacq., Rubiaceae). Seed rain at one non-excluded plot was dominated by the wind-dispersed early-successional tree Heliocarpus sp. (Tiliaceae). Richness and seed density increased significantly in the second year of exclusion; however, by the third year, richness remained constant while seed density decreased. Seed rain was richer and more abundant during the dry season and was dominated by wind-dispersed species. Phenology, successional status and the dispersal modes of woody species explained most variance in richness and seed density of seed rain in early-successional dry forest. Seeds of early-successional species were dispersed in equal measure by abiotic and biotic vectors, whereas biotic vectors dispersed a higher density of late-successional seeds. The amount and timing of fall of abiotically dispersed seeds of the three most abundant species in the standing tree community may prolong their current domination of the landscape. However, even when richness in the seed rain within exclosures remained constant through time, composition was gradually shifting towards animal-dispersed species which may start a positive feedback producing an increase in animal visitation and a further increase of richness.  相似文献   

13.
【目的】揭示呼伦贝尔沙区4种生境土壤真菌群落结构与多样性及其影响因素,探究不同生境对土壤真菌的影响。【方法】选择裸沙地、草地、樟子松人工林和樟子松天然林4种生境土壤真菌为研究对象,采用野外调查、ITS高通量测序结合RDA分析,比较分析不同生境土壤真菌种群特征。【结果】呼伦贝尔沙区土壤共检测到真菌5门22纲73目28科257属。其中,裸沙地和草地土壤优势真菌门为子囊菌门,樟子松人工林和天然林中优势真菌门为担子菌门。优势属共31属,裸沙地、樟子松人工林的优势属分别是被孢霉属和丝膜菌属,草地和天然林土壤中的优势属分别为被孢霉属和Archaeorhizomyces、红菇属和Geminibasidium。其中裸沙地和草地、樟子松人工林和天然林的土壤真菌进化分支更为接近。草地土壤真菌物种丰富度和个体数最高,分布最为均匀;裸沙地其次;樟子松天然林和人工林物种丰富度、个体数和多样性指数较低,分布也较为集中。土壤真菌群落分布的主要影响因子是土壤含水量,优势真菌属分布受多种环境因子影响,土壤孔隙度、含水量、有机质分别是被孢霉属、Archaeorhizomyces、丝膜属的主导影响因子,全磷则是红菇属和Geminibasidium的主导影响因子。【结论】呼伦贝尔沙区4种生境土壤真菌主要由子囊菌门和担子菌门组成,其中裸沙地和草地、樟子松人工林和天然林土壤真菌群落结构相似度较高。多类型草本植物使真菌种类增多且分布更为均匀,樟子松在一定程度上降低真菌数量和种类,并使其分布更为集中。不同生境的不同植被可以改变土壤性质,而土壤水分、营养元素及孔隙结构等土壤环境因素会直接影响4种生境土壤优势真菌属的代谢过程和功能特征,因此4种不同生境真菌群落结构及多样性呈显著差异。  相似文献   

14.
尖峰岭位于海南岛西南部,植物生长茂密,树种繁多,植被和土壤类型的垂直带谱明显,保存着较为完整的热带森林。因此,研究尖峰岭热带林生态系统的物质循环和了解放线菌在不同生态环境中的分布,对合理利用和开发热带森林资源,更好地发挥经济效益,具有重要意义。 1982—1983年,笔者对尖峰岭热带林三种不同森林类型土壤放线菌数量和组成特性作了调查,放线菌培养采用高泽氏一号琼脂培养基,链霉菌类群鉴定根据《链霉菌鉴定手册》,有关林地概况、土壤样品采集时间和方法见初报Ⅰ。  相似文献   

15.
Soil organisms comprise a large number of species that play a role in various ecosystem functions and provide valuable ecosystem services that sustain soil quality. The objective of this study was to characterize the meso- and macrofauna in soil and litter with different types of plant cover (Acacia auriculiformis A. Cunn. ex Benth., Mimosa caesalpiniifolia Benth., pasture and secondary forest) at different sampling times (dry season: June and September and rainy season: February). The faunal communities were sampled over during 15 days with a Berlese-Tullgren apparatus. The density of the total fauna ranged from 822 to 6,368 individuals m?2 in the litter and 99 to 1,222 individuals m?2 in the soil. The richness ranged from 9.4 to 12 in the litter and 6.4 to 8.8 in the soil. In all, 12,596 individual organisms were recovered from the soil and litter samples, and 8,012 individuals were found in the litter. Seasonal variation influenced the density and richness of the total fauna and the occurrence of functional groups, particularly the populations of microbial grazers, predators and herbivores, but this influence depended on the plant cover. Most groups that were found during the three sampling periods and in all types of plant cover belonged to two functional groups: social insects (Formicidae) and microbial grazers (Collembola). The plant cover types showed homogeneity in the distribution of the soil-litter fauna, and the development of a litter layer by leguminous tree plantations in a degraded pasture produced a higher abundance and diversity of soil fauna.  相似文献   

16.
Many forest species can be found in understory vegetation of old plantation plots, despite the fact that the native vegetation was a poor savanna growing on highly nonfertile sandy soils. The aim of the present paper is to describe the changes that occur in the environmental conditions when savanna is planted with fast-growing trees, and is particularly concerned with vegetation and soil macrofauna. The study was carried out in industrial eucalyptus plantations, and in experimental Acacia and pine plantations. Most plots were located on sandy soil, but some measurements were also carried out on clay soil planted with the same species in order to assess the influence of soil type.

A strong correlation was shown between the age of the eucalyptus trees and the percentage of forest species in undergrowth, emphasizing the progressive change from savanna vegetation towards forest vegetation.

Biomass and density of macrofauna were very low in both sandy and clayey savanna soils, total biomass being 3.3 and 5.8 g/m2 respectively. Soil macrofauna became more important as the age of plantations increased, and biomass reached 29 g/m2 in the 20-year-old eucalyptus plot on sandy soil, and 74 g/m2 in 26-year-old eucalyptus plantation on clay soil, compared to 33 g/m2 in the natural forest plot on sandy soil; however, frequency of occurrence and number of taxa were lower in old eucalyptus plot as compared to forest. Large differences in the abundance of macrofauna were observed in relation to planted species. Acacia was most favourable to soil macrofauna, with a total biomass of 60 g/m2 on sandy soil and many taxa present. Pine plantations had a poor macrofauna and several taxa were lacking, particularly in the sandy soil.

Total macrofauna frequency was significantly correlated with the percentage of forest species in understory vegetation. Both were correlated with soil pH and soil organic-matter content. The results suggest that soil organic matter and litter quality are of main importance in changing the above- and below-ground habitat in plantations.  相似文献   


17.
微生物通常是土壤中有机质分解以及养分积累的积极参与者,因此,对林地土壤微生物分析,是森林生态系统中物质循环的重要内容之一。本文仅就两年的调查研究,对其中丝状真菌和固氮菌在三个森林类型林地的分布状况及组成特征进行初步分析。  相似文献   

18.
This study estimates the aboveground biomass accumulation after forest clearing and slash burning and describes the structure and successional development of the secondary forest in the seasonally dry southern Amazon. The original burn study was conducted in four land clearings in 1997, 1998, and 1999. The size of the clearings varied from 1 to 9 ha. The native forest was felled, allowed to dry for approximately three months and then burned by the end of the dry season. A census was conducted in the central 1-ha forest on each site prior to the area's felling and burn. The aboveground biomass (AGB) and structure were similar to other primary tropical forests. However, the high density of Cecropia spp. before the forest felling and burn treatment indicates past low intensity disturbances. Seven and eight years after the fire, the fallow forests were still in an early successional stage dominated by Cecropia spp. The four areas had a high biomass accumulation during the studied period, varying from 7.5 to 15.0 Mg ha−1 year−1. The lower biomass accumulation in one plot was an effect of a higher fire severity, produced by the one-year difference in time between slash and burn of the forest, slowing the natural regeneration of Cecropia spp. The time needed for this forest to recover to the pre-fire AGB levels ranged from 20 to 30 years, assuming the current AGB accumulation rates are maintained. Considering these results, the maintenance of regenerating secondary forests in the Amazon would be a significant contribution to soil and watershed protection, minimizing biodiversity losses and perhaps mitigating climatic changes effects in the region.  相似文献   

19.
基于对哈巴雪山省级自然保护区植被多样性专题考察,总结归纳保护区植被景观特征及水平、垂直分布规律。对保护区植被演替状况进行科学分析,结果认为,显域植被类型显示出顶级群落特征,云南松林、华山松林、高山松林为水平地带相对稳定的次生(亚演替)顶级群落。充分挖掘各种天然植被的保护价值,并从自然性、稀有特有性、生物多样性、脆弱性、生态系统重要性、易受干扰性6个方面确定保护区需要优先保护的植被类型。  相似文献   

20.
通过盆栽对比试验,对酸性土和石灰土上生长的云南紫荆(Cercis yunnanensis)幼苗的生长和光合特征进行研究。结果表明:经过一个生长季节后,石灰土上云南紫荆的生长比酸性土上好,具有较高的生长量和生物量积累。云南紫荆对石灰岩土壤适应能力较强,可作为石灰岩山地的造林树种进行推广。  相似文献   

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