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1.
By means of a cluster analysis, we classified 135 relevés of the forests of the Muniellos Reserve into 8 groups and the species in these relevés into 28 groups. The concentration analysis applied allows to study the relationship between relevé group and species group. The forest types in Muniellos Reserve are: mixed riverside forest, mixed forest with hazel, semideciduous pyrenean oak forest, xerophilous and mesophilous sessile oak forest, beech forest and open and thick birch forest. These forest types are characterized floristically, structurally and ecologically. The pattern of distribution of forest types in the Muniellos Reserve is also discussed; in the siliceous areas of the Orocantabric province this pattern is widespread, but differes to some extent from the accepted pattern.  相似文献   

2.
Comparisons are made between a virgin forest remnant (primeval forest) and a lightly managed (near‐to‐nature) forest with regard to horizontal forest structures, the structure of forest stands, and the diversity of plant and bird species. In the virgin forest remnant the proportion of canopy gaps is smaller, there are no stands in the developmental phase of a pole stand (10 < cm d.b.h. < 30 cm), and both the growing stock and the proportion of less vigorous trees are considerably greater. In addition, there is a higher percentage of dead trees, a smaller proportion of minor tree species and a considerably lower diversity of plants. The diversity of bird species is similar for each forest type, but rare bird species are confined to the virgin forest remnant. The biological differences between the two types of forest have led to changes in the physical site conditions. The results of the research are valuable in assessing the consequences of near‐to‐nature forest management.  相似文献   

3.
森林土壤氮转化的微生物功能研究   总被引:2,自引:1,他引:1  
本文研究了不同林型下土壤(A+6层和A_1层)微生物、土壤酶活性在森林土壤氮转化中的作用。结果表明不同林型下土壤具有不同的固氮作用、反硝化作用、氨化作用和硝化作用速率,即阔叶林>针阔混交林>针叶林。已经证明,固氮作用主要存在于森林土壤的A_1层,反硝化作用主要存在于A_0层。森林土壤存在2种硝化作用过程,即由自养微生物所引起的自养硝化作用过程和异养微生物所引起的异养硝化作用过程。它的存在与林型有关,某些森林土壤中这2种硝化作用过程都存在,如针阔混交林下的A_0层和A_1层。有些林型下土壤,则以异养硝化作用过程为主,如针叶林的A_0层。  相似文献   

4.
森林具有生态、经济、社会和文化等多种功能和多重价值。森林文化价值是人类与森林生态系统长期交往互动、和谐共生中所发育形成并提供人们的精神服务和文化产品的总和,作为森林资源价值构成的重要组成部分,其价值评估理论和方法尚在探索完善中。通过理论分析和案例验证结合的方法,提出了"人与森林共生时间"的核心理论和森林文化价值评估方法,构建了包括8项一级指标、22项二级指标、53项指标因子的森林文化价值评估指标体系,核定了指标权重和综合指标系数,并对森林文化价值物理量和价值量开展评估。研究发现,森林文化价值与人在森林中停留、互动共生的时间成正比,人与森林的共生时间是相对的和动态变化的;其价值高低,与自然力的作用、森林资源要素和环境结构密切相关;不同区域森林文化价值存在梯度差异。通过我国各省区市案例结果表明,森林文化价值量与森林覆盖率、森林常驻人口、森林质量、森林的文化和自然遗产、森林游憩和森林的文化产业、区域居民收入呈现正相关关系。  相似文献   

5.
丁一阳  毛子军  张玲  丁力 《植物研究》2015,35(4):604-611
土壤有机碳含量是全球生态系统碳储量变化的重要指标之一,本研究以空间替代时间序列的方法,分别选取了小兴安岭地区原始阔叶红松林和枫桦次生林并测定土壤有机碳库、土壤全氮含量、土壤微生物量碳及土壤相关理化性质,结果表明,土壤有机碳含量(SOC)、土壤全氮含量(TN)、土壤微生物量碳(MBC)、土壤含水率等指标随着土壤层的深度增加而逐渐减少最后趋于稳定,而土壤容重随着土壤层的加深而增大。在原始林中0~10和10~20cm层的SOC、TN含量差异不显著,而次生林则差异显著。原始阔叶红松林和枫桦次生林的土壤有机碳密度(SOCD)分别为21.46和21.3 kg·m-2,差异不显著。原始林和次生林的平均有机碳含量分别为35.79,28.6 g·kg-1,土壤全氮含量分别为2.86,1.83 g·kg-1,枫桦次生林MBC与SOC的线性相关性高于原始林。结果表明原始林土壤肥力高于次生林,在今后次生林的管理中应适当混栽针叶树种,原始林中应适当间伐使地下碳储量增加。  相似文献   

6.
吕富成  马建勇  曹云  延晓冬 《生态学报》2022,42(7):2810-2821
森林生态系统是陆地碳循环的重要组成部分,其固碳能力显著高于其他陆地生态系统,研究森林生态系统碳通量是认识和理解全球变化对碳循环影响的关键。碳循环模型是研究森林生态系统碳通量有效工具。以长白山温带落叶阔叶林、千烟洲亚热带常绿针叶林、鼎湖山亚热带常绿阔叶林和西双版纳热带雨林等4种中国典型森林生态系统为研究对象,利用涡度相关2003-2012年观测数据,评估FORCCHN模型对生态系统呼吸(ER),总初级生产力(GPP),净生态系统生产力(NEP)的模型效果。结果表明:(1) FORCCHN模型能够较好的模拟中国4种典型森林生态系统不同时间尺度的碳通量。落叶阔叶林和常绿针叶林ER和GPP的逐日变化模拟效果较好(ER的相关系数分别为0.94和0.92,GPP的相关系数分别为0.86和0.74);(2)4种森林生态系统碳通量季节动态模拟值和观测值显著相关(P<0.01),ER、GPP、NEP的观测值和模拟值的R2分别为0.77-0.93、0.54-0.88和0.15-0.38;模型可以很好地模拟森林生态系统不同季节碳汇(NEP>0),碳源(NEP<0)的变化规律;(3)4种森林生态系统碳通量模拟值与观测值的年际变化有很好的吻合度,但在数值大小上存在差异,模型高估了常绿阔叶林的ER和GPP,略微低估了其他3种森林生态系统ER和GPP。  相似文献   

7.
滇中常绿阔叶林及云南松林枯落物的初步研究   总被引:11,自引:0,他引:11  
刘文耀  荆贵芬  郑征   《广西植物》1989,9(4):347-355
本文以滇中高原为背景。研究了通海秀山常绿阔叶林及云南松林的凋落物的数量、组成、季节变化规律、营养元素(N、P、K、Ca、Mg、Cu、Mn、Fe)含量、以及林地枯枝落叶层的现量,研究结果表明滇中地区森林的年凋落量是较大的,营养元素含量及贮量也是丰富的。两类森存林的凋落规律相似,常绿阔叶林的凋落量、营养元素含量及其贮量都大于云南松林,但两类森林的枯枝落叶现存量则相接近,说明常绿阔叶林的物质循环周期较云南松林短。文章提出为了提高森林土壤肥力、加快生物循环过程,增加生物产量,要注意保存林地内还原于土壤中的所有凋落物。  相似文献   

8.
Abstract. Land flatworms (Platyhelminthes: Terricola) are sensitive to environmental changes and might be used as biological indicators of the degree of disturbance of their habitats. Nevertheless, studies on the structure of land flatworm communities are rare. In the present study, we investigated the terrestrial flatworm communities in two types of ombrophilous forest, Atlantic forest and Araucaria forest, aiming to answer the following questions: (1) Is the community structure of the two types of ombrophilous forest different? (2) Are there differences, regarding community structure, among distinct fragments of Araucaria forest? (3) Are there indicators of edge effects in these communities? The study site, the National Park of Aparados da Serra, is mainly covered, at high altitudes, by fragments of Araucaria forest immersed in a matrix of open areas (grasslands) and, in low altitudes, by a continuous Atlantic forest. We conducted monthly surveys in the two types of forest with three replications per forest type over a period of 2 years. Results indicated that: (1) community structure is clearly distinct between the two types of forest, as well as among fragments of the Araucaria forest; (2) there are no apparent edge effects; (3) the diversity indices of the two types of ombrophilous forest are not significantly different (Atlantic forest—H′=2.87, Araucaria forest—H′=2.55; p>0.05); and (4) there are significant differences in diversity indices between two fragments of Araucaria forest (H′=2.92 and 2.47; p<0.001). The following factors could affect community structure: type of vegetation, degree of human disturbance, and abiotic factors, such as pH and temperature.  相似文献   

9.
运用非线性联立方程组建模理论建立红松立木相容性生物量模型,然后利用模型计算出人工红松各个样地林木各器官和样地总生物量。以林分年龄、林分平均胸径、林分密度等因素为制约条件,讨论分析林分生物量在林木各器官之间的分配规律,并且探究林分年龄、林木大小和林分密度的变化对林分生物量的影响。结果表明:幼龄红松人工林林分生物量与平均胸径成正相关关系;林分密度对林分生物量影响较大,并且随着密度的增大而增大,且最适合的林分密度范围是1 000~1 400株·ha-1;红松人工幼、中龄林林分生物量各器官分配规律相同,表现为树干树根树枝树叶,地上生物量占林分生物量79%左右;林分地上和地下生物量大概呈3.8∶1的比例。  相似文献   

10.
We compared the relative contribution of blackwater inundation forest (igapó) and unflooded (terra firme) forest for regional bird species diversity in the lower Rio Negro region. For analyses of habitat preference we used mist-net samples and an unpublished bird species check-list. The igapó forest had lower bird species diversity than the terra firme forest. However, some 14% of the forest bird species in the region are restricted to igapó forest. Species composition was found to be distinct between the understories of the two forest types. Common forest bird guilds in the Neotropics such as ant-following birds avoid igapó forest. The differential habitat selection among birds in the inundated and unflooded forest is likely to result from vegetation structure and biological interactions such as aggressive behaviour. Since the inundated forest has a typical biota, conservation efforts needs to be directed to protect these habitats. Unfortunately, inundation forests are threatened by several human actions, especially dam construction. The extent of protected areas in the Brazilian Amazon is insufficient for the adequate protection of the inundated habitats, because it includes only 3% of the total area.  相似文献   

11.
Nearly 40% of the remaining Atlantic Forest in southern Bahia state, Brazil, is a rustic agroforest of cacao (Theobroma cacao). These traditional shade plantations, locally known as ‘cabrucas’, are habitats for forest dwelling species. Here we investigated the potential role of this traditional crop as a support for bat assemblages in southern Bahia, establishing the extent to which the bat community structure found in this agricultural system is influenced by the proximity of forest tracts. We compared the bat community attributes (richness, diversity and dominance) and species-level response (capture frequency) between native forest tracts and shade cacao plantations located in two distinct landscapes, which varied in total amount of forest (patch sizes and total forested area) and in their proximity to forest tracts. The cabrucas contiguous to forest tracts showed a rich and abundant bat community, with samples showing capture rates, species richness, diversity and evenness significantly higher than those reported for forest tracts. This situation changes, however, when shade plantations are located at some distance from forest tracts ( > 1000 m). Bat communities in these isolated cabrucas are less diverse than those found in forests and nearby cabrucas, but in both cases, species usually associated with pristine habitats were found. These findings suggest that cabrucas per se are not forest surrogates, and their potential to harbor forest dwelling bat species is closely linked with the existence of nearby forest tracts that may act as a source for species populations. Therefore, the entire landscape should be considered for management, taking into account that maintenance of cabrucas together with the preservation and restoration of forest patches is probably direly needed if one wishes to conserve the bat diversity in southern Bahia for the long term.  相似文献   

12.
基于人林共生时间的森林文化价值评估   总被引:2,自引:0,他引:2  
森林的文化价值是森林价值的重要组成部分,探索森林文化价值量化评估方法具有重要意义。通过文献成果集成、理论分析、案例验证相结合的方法,研究了公园尺度和区域尺度森林文化价值的量化评估方法;运用评估方法评估全国和各省森林的文化价值。森林的文化价值是森林对人类的身体健康、生活质量和精神发展所产生的积极影响。评估森林文化价值的高低,可采用以"人林共生时间"为核心的评估方法,以"文年"作为计量单位,简称"文年评估法"。森林公园的文化价值用游人在森林公园中逗留的时间来反映。区域森林的文化价值由居住人口与森林共生的基本生活时间和森林文化活动时间的两者之和共同反映。评估结果表明,中国森林公园的文化价值总体上具有很大提升空间;全国不同省份的森林文化价值总量、地均、人均、林均状况都存在很大差异;四川、广东、云南、福建、黑龙江是森林文化价值大省;上海、福建、浙江、广东、北京对单位土地森林文化价值开发充分;福建、吉林、云南、黑龙江、四川人均森林文化福利优厚;上海、天津、江苏、北京、河南对森林文化价值的需求旺盛。  相似文献   

13.
Abstract.
  • 1 Samples of Microlepidoptera (including Pyraloidea) collected at light in mangrove forest, lowland mixed dipterocarp forest, and montane oak-laurel forest in Borneo are compared.
  • 2 Diversity (Williams' alpha) is very high in lowland forest, with a value of 414; it is lower, 226, in montane forest and very much lower, 47, at the edge of mangrove forest.
  • 3 There is some evidence that apparent diversity increases with accumulation of samples.
  • 4 Samples from the three forest types have very few species in common and come from separate assemblages.
  • 5 Pyraloidea in samples taken 1km apart in lowland forest represent an assemblage common to the two sites but Microlepidoptera samples appear to represent slightly different assemblages.
  • 6 There are no abundant species in lowland or montane forest: species with more than ten individuals comprised less than 4% of the samples. Four common species in mangrove forest accounted for 34% of the sample.
  • 7 The proportion of Tineoidea, Gelechioidea and Pyraloidea is lower in montane forest than in lowland forest, while that of Yponomeutoidea and Tortricoidea is higher.
  • 8 Just eight families of Microlepidoptera account for 90% of the species in samples from all three forest types.
  • 9 The number of species of moths in Borneo is suggested to be in excess of 8500.
  相似文献   

14.
西双版纳地区六种林型地表蜘蛛多样性比较研究   总被引:7,自引:0,他引:7  
郑国  杨效东  李枢强 《昆虫学报》2009,52(8):875-884
为探索地表蜘蛛多样性及其变化与森林类型和管理方式的关系, 在西双版纳勐仑自然保护区选择热带季节雨林、石灰山季节雨林和山地常绿阔叶林, 在自然保护区附近选择人工纯林、胶茶群落和橡胶林, 共6种林型, 每种林型选择3块样带, 共设置研究样地18块, 分别于2006年12月上旬(雾凉季)、2007年3月下旬(干热季)和2007年7月上旬(雨季), 以单位地表面积法收集地表蜘蛛的物种组成和数量数据, 并以蜘蛛种类和数量分布为属性进行典范对应分析(CCA), 探讨不同类型植被与地表蜘蛛多样性的关系。共采集蜘蛛标本9 849头, 用于统计分析的成熟蜘蛛3 119头, 归属于30科, 其中幽灵蛛科、皿蛛科、球蛛科和小密蛛科是地表蜘蛛的优势类群。各林型科的数量为: 热带季节雨林24科, 石灰山季节雨林22科, 山地常绿阔叶林22科, 人工纯林20科, 胶茶群落21科, 橡胶林19科; 各林型特有科数量: 热带季节雨林2科, 山地常绿阔叶林2科, 橡胶林1科; 而仅在雨林中分布的科4个(占全部30个科的13.3%), 仅在自然林中分布的科6个(20.0%), 仅在人工林中分布的科1个(3.3%)。从蜘蛛的数量分布看, 个体密度在热带季节雨林显著高于其他5种林型; 橡胶林多样性指数和丰富度指数显著低于3种自然林, 而均匀度指数的最低值也同样在橡胶林出现。CCA分析和聚类分析的结果表明, 6种林型趋于分成2组, 即: 自然林和人工林; 在自然林中两种次生林的相似程度更高; 人工林中人工纯林(非橡胶林)与胶茶群落的相似程度更高。以上结果表明: (1)森林砍伐后种植人工林措施改变了该地区地表蜘蛛群落的物种分布格局; (2)蜘蛛多样性随着人为干扰程度增加有减少的趋势; (3)减少人为干扰和增加植被群落多样性(橡胶林中种植茶树)对保护和恢复物种多样性有重要意义。  相似文献   

15.
This study sought to investigate land‐snail diversity, abundance and distribution in Arabuko Sokoke forest. Sampling was done using standard timed direct search and litter sample methods. In total, 25 species and 1263 specimens were recorded. The 25 species rank Arabuko Sokoke forest as the second richest coastal forest in land snails in East Africa. The 25 species, however, are not uniformly distributed across the forest. The majority of the snails were localized with low levels of abundance. Eight species were restricted to one forest type, whereas those shared among forest types tended to concentrate in one forest type. Only five species, Gulella radius, Gulella foveolata, Gonaxis kibweziensis, Pseudoglessula biovini and Opeas gracilis, were widespread. The highest snail diversity was recorded in the mixed forest, implying that special conservation of this habitat is necessary for retention of the broadest molluscan diversity. The observation that some species rare in the mixed forest were recorded in excess from Brachystegia and Cynometra forest, further suggests that conservation of the entire A. Sokoke forest is critical for efficient molluscan conservation. Species recorded in low levels of abundance are probably declining and investigation on the snails' ecology to understand factors that influence the snails' diversity is recommended.  相似文献   

16.
基于环境星与MODIS时序数据的面向对象森林植被分类   总被引:8,自引:0,他引:8  
林区地形复杂、植被分布无序,且森林植被光谱信息相近,因而森林二级类型边界的确定成为土地覆盖遥感分类的难点。选择吉林省东部山区为研究区,以环境星影像(HJ-1 CCD)和中等分辨率成像光谱仪(MODIS)时序数据为基础,采用面向对象的分类方法进行森林植被类型的提取。分类特征参数主要选取了HJ-1 CCD的光谱和纹理特征,以及MODIS时序数据的物候特征。研究区总体分类精度为91.5%,Kappa系数为0.88,森林二级类型的分类精度均较高,其中落叶阔叶林的制图精度达到了97.1%。所用的面向对象分类方法与未加入物候特征的面向对象分类方法相比,森林二级类型的分类精度得到大幅度提高。  相似文献   

17.
陕北黄土高原侧柏疏林草原的初步研究   总被引:4,自引:0,他引:4  
侧柏疏林草原是陕北黄土高原森林草原地带东部重要群落类型之一,现仅残存于东北部的神府地区,常见者有4个类型:①茭蒿-侧柏疏林草原;②白草-侧柏疏林草原;③茭蒿+长芒草-侧柏疏林草原;④细叶柴胡+长芒草-测柏疏林草原。根据群落中乔木的更新状况分析,今后在气候不发生明显波动的情况下,侧柏疏林草原仍为该森林草原地带稳定的群落。  相似文献   

18.
We examine whether rain forest dung beetle species found in plantations in Sabah, northern Borneo, tend to be endemic or geographically widespread. In addition, linear regressions of abundance vs. distance from a major river in primary rain forest are calculated to see if species found in plantation forest show affinity to one specific biotope (riverine vs. interior forest) in their natural habitat. Results show that 14 of the 40 species recorded from plantations are endemic to Borneo. Only edge‐specialist endemic species are found in plantation forest, with no interior‐forest specialists recorded. Data suggest that endemic species that are adapted to more exposed conditions in primary rain forest, such as riverine species, can in some instances tolerate man‐made habitats. Twenty‐nine species (±SE 4.0) per transect are recorded from plantation transects, whereas 44.2 (±1.7 SE) are recorded in primary rain forest. As species richness is much lower in plantations than natural forest, implying loss of biodiversity, we conclude that measures of biogeographic distinctiveness, whereby endemic species confer higher values, may be misleading unless they take into account edge‐affinity. Local‐ as well as regional‐distributional data may therefore be needed to interpret correctly patterns of species assemblages in derived forest ecosystems.  相似文献   

19.
Studies of spatial forest patterns have traditionally focused on habitat remnants within a landscape, but few have explicitly accounted for natural habitat patterns inherent to those landscapes. At broader scales, all cover types are to some degree subdivided. In boreal forest landscapes, forests, peat lands and water bodies form a variety of different spatial structures depending on their proportions and arrangement. To assess the spatial arrangement of forest patches relevant to organisms and ecological processes, we systematically sampled and analysed 57 boreal forest landscapes (10,000 ha in size) in central Finland. Our results show that even though forest is spatially very subdivided into discrete patches in boreal landscapes it becomes generally well-connected if narrow non-forested gaps are ignored. The proportion of forest cover varied from 17.8 to 75.3% and the number of discrete forest patches from 37 to 213. The average percolation threshold for forest cover was 46.8%. If ≤100 m wide non-forested gaps were ignored and forest patches were joined, the percolation threshold dropped to 33.3%. There were on average 13 discrete clusters of forest patches if forest patches within 200 m distance were combined. These results suggest that if a boreal forest species is able to cross even relatively narrow non-forested gaps, it is likely to perceive these boreal forest landscapes as continuous. Even though our present analysis was based on static forest cover patterns, it is important to consider landscape pattern domains when assessing habitat fragmentation and its consequences to populations of organisms.  相似文献   

20.
This paper is intended to provide a brief review of the tropical seasonal forest, one type of the tropical moist forests in monsoon Asia. It will also focus on and summarise issues of current concern in relation to their depletion and global environmental issues. Tropical moist forests occur in the rainy tropical and monsoon tropical climate types. The tropical moist evergreen forest or the tropical rain forest, which account for two-thirds of the tropical moist forests are rich in biodiversity and contain valuable tropical hardwood. The tropical moist deciduous forest or the tropical seasonal forest which lie along the fringes of tropical rain forest, are less complex than the tropical rain forest and have more distinct wet and dry periods. Broadleaved deciduous trees of the genera Tectona, Shorea, and Dipterocarpus are predominantly in this forest type. Currently estimates have found that more than 17 million hectares of forest mainly tropical moist forests are being lost each year. There is a widespread recognition that agriculture and the burning of tropical moist forests contribute to global warming but to a much lesser extent than the combustion of fossil fuels and industrial activities in the developed world.  相似文献   

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