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1.
Vertical and seasonal distributions of flying beetles were investigated in asuburban temperate deciduous forest in Kanazawa, Japan using water pan traps to determine the abundance and composition among vertical strata, change in the abundance and composition through seasons and determinant factors in generating the distributions. Traps were placed at three levels (0.5 m, 10 m, and 20 m above ground) on a tower. Samplings were carried out seasonally from May to November in 1999 and 2000. Variations in the abundance of flying beetles were observed from different layers. The results showed that the abundance and composition of flying beetles varied among strata and seasons. In both 1999 and 2000,Elateridae was consistently most abundant in the bottom layer, while Attelabidae and Cantharidae were most abundant in the upper layer. In 1999, Eucnemidae and overall scavengers were most abundance in the bottom layer, but results were not consistent with those in 2000. In general, the abundance of herbivores reaches a peak in the early season(May/June) and decreases in the following months. Peaks of abundance in predators vary vertically. In the bottom layer a peak was observed in the early season (May/June), while in the upper layer this was observed in July. Scavengers had two peaks, in May/June and September. These patterns indicated that vertical distributions in the abundance of differentfeeding guilds varied through seasons.  相似文献   

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3.
张忠华  胡刚  祝介东  倪健 《生态学报》2012,32(18):5663-5672
物种多样性的空间分布格局及其尺度效应是生态学研究的重点,对于理解物种多样性的形成和维持机制以及生物多样性的管理和保护均具有重要意义。以贵州茂兰国家级自然保护区分布的亚热带原生性喀斯特常绿落叶阔叶混交林为研究对象,分析了2个1hm2(100m×100m)样地中物种多度和丰富度的空间分布特征及其与取样尺度的关系,采用方差和变异系数描述多度和丰富度在5个尺度(5m×5m,10m×10m,20m×20m,25m×25m,50m×50m)上的空间变异性。结果表明:(1)两个样地的物种多度和丰富度具有尺度依赖性特征;(2)由于多度具有叠加性,物种多度的方差随着尺度的增加呈线性增加,而变异系数呈线性下降;(3)丰富度的方差随尺度的增加表现出单峰分布的特征,在25 m×25 m尺度上达到最大值,变异系数则随取样尺度的增加而呈线性下降。研究表明,物种多度具有尺度推演规律,而丰富度却没有,因此,应慎重进行物种丰富度的尺度推演。在分析喀斯特森林物种多样性时,应注重尺度效应带来的影响。  相似文献   

4.
《植物生态学报》1958,44(7):730
分析不同树种叶片性状的变化有助于了解植物群落结构。该文通过对典型阔叶红松(Pinus koraiensis)林15种阔叶树种的比叶质量、叶片厚度、叶干物质含量、叶绿素含量指数、叶片碳、氮、磷含量的测定, 分析了冠层高度对叶性状及叶性状间相关关系的影响。结果表明, 水曲柳(Fraxinus mandshurica)和大青杨(Populus ussuriensis)上层的比叶质量显著大于下层, 而其他树种冠层间的比叶质量无显著变化; 叶绿素含量指数在白桦(Betula platyphylla)和春榆(Ulmus japonica)冠层间的分布分别为上层显著大于下层和上层显著大于中层; 单位质量氮含量在水曲柳的中层显著大于上层。叶片性状间存在着广泛的相关性, 比叶质量与叶片厚度、干物质含量在三层间均呈显著正相关关系, 而有些性状, 只在一或二个冠层中存在一定的相关性。山杨(Populus davidiana)和大青杨的叶片倾向于选择光合能力较低、营养浓度较低、呼吸速率较慢的一端, 而黄檗(Phellodendron amurense)和山槐(Maackia amurensis)叶片更倾向于光合能力强、营养物质浓度高的一端。不同树种对光照响应的差异可能会改变不同冠层中叶片的形态和化学性状, 从而有助于群落构建和物种共存。  相似文献   

5.
分析不同树种叶片性状的变化有助于了解植物群落结构。该文通过对典型阔叶红松(Pinus koraiensis)林15种阔叶树种的比叶质量、叶片厚度、叶干物质含量、叶绿素含量指数、叶片碳、氮、磷含量的测定, 分析了冠层高度对叶性状及叶性状间相关关系的影响。结果表明, 水曲柳(Fraxinus mandshurica)和大青杨(Populus ussuriensis)上层的比叶质量显著大于下层, 而其他树种冠层间的比叶质量无显著变化; 叶绿素含量指数在白桦(Betula platyphylla)和春榆(Ulmus japonica)冠层间的分布分别为上层显著大于下层和上层显著大于中层; 单位质量氮含量在水曲柳的中层显著大于上层。叶片性状间存在着广泛的相关性, 比叶质量与叶片厚度、干物质含量在三层间均呈显著正相关关系, 而有些性状, 只在一或二个冠层中存在一定的相关性。山杨(Populus davidiana)和大青杨的叶片倾向于选择光合能力较低、营养浓度较低、呼吸速率较慢的一端, 而黄檗(Phellodendron amurense)和山槐(Maackia amurensis)叶片更倾向于光合能力强、营养物质浓度高的一端。不同树种对光照响应的差异可能会改变不同冠层中叶片的形态和化学性状, 从而有助于群落构建和物种共存。  相似文献   

6.
《Annales de Paléontologie》2019,105(2):119-122
A new fossil species from the Eocene Baltic amber of the extinct tribe Mimoplatycini Kazantsev, 2013 (Cantharidae Malthininae), is illustrated and described here. Mimoplatycis marchettii sp. nov. is characterized by a transverse but interrupted carina in the middle of pronotum. The tribe is known from Baltic and Rovno amber, and the pronotum with carinae similar to Lycidae could be interpreted as mimicry. The pronotal shape is here indicated as a diagnostic character of the species level.  相似文献   

7.
To clarify the effects of forest fragmentation in urban landscapes on the abundance, species richness, dominance, and species composition of ground beetles (Coleoptera: Carabidae and Brachinidae), we compared the beetles collected in 12 pitfall traps from April to July and from September to November between three continuous suburban forests and eight isolated urban forests (0.06–1.02 ha), most of which were in the precincts of shrines and temples in Hanshin District, Honshu, Japan. A total of 28 species and 4178 individuals of ground beetles were collected. Segregation of urban forests from continuous suburban forests has changed the species composition and resulted in the loss of some large‐sized forest species and the addition of some non‐forest species. Simpson's index of dominance (λ) also increased in the urban forests. The richness of forest species markedly decreased with the reduction in forest area but not with the distance from continuous forests, although the species richness of non‐forest species did not change with them. Also, species composition changed only with forest area. These findings indicate that continuous forests do not necessary serve as a “mainland” for urban forest species and that every urban habitat, however small in size, acts as a temporary reservoir of species. In comparison with populations of small‐sized species, populations of large‐sized forest species appeared to decline more readily during forest fragmentation.  相似文献   

8.
Insect–fungal interactions are an important but understudied aspect of tropical forest ecology. Here we present the first large‐scale study of insect communities feeding on the reproductive structures of macrofungi (basidiomes) in the Neotropics. This trophic interaction is not well characterized in most ecosystems; however, beetle consumption of basidiomes is thought to be affected by fungal factors, via mechanisms analogous to those observed in plant–herbivore interactions and in some interactions with fungi as hosts in the Holarctic region. We investigated how the composition of beetle assemblages varies as a function of fungal taxonomic distance, basidiome consistency, and hyphal systems. We collected 367 basidiomes belonging to the orders Polyporales and Hymenochaetales in the subtropical Araucaria angustifolia forest region of southern Brazil, along with any fauna present or without it. Basidiomes were maintained individually in the laboratory in plastic containers for up to three months to allow beetles to develop to adulthood, at which point the beetles were collected. We found that 207 basidiome specimens representing 40 species were associated with beetles. We recorded 447 occurrences of Coleoptera, representing 90 morphospecies from 20 families. We found that assemblages of fungivorous Coleoptera were more similar among more closely related fungi. Furthermore, the beetle assemblages varied as a function of basidiome toughness, which is influenced by sporocarp consistency and hyphal system type. The associations between beetles and basidiomes resemble those reported previously in temperate zones, suggesting continuity in the structure of such associations across a wide latitudinal range.  相似文献   

9.
The values and variation characteristics of energy components, their relationship with net radiation and the characteristics of water balance in the forest were analyzed, based on the observation data of energy fluxes, meteorological parameters and biomass in a tropical seasonal rain forest in Xishuangbanna from January 2003 to December 2004. The results show that annual net radiation was 3516.4 MJ/(m2 · a) and 3516.6 MJ/(m2 · a) in 2003 and 2004, respectively, of which 46% and 44% were used in latent heat flux, and 12% and 11% were lost as sensible heat flux. Annual mean canopy surface conductance was 10.3 mm/s and 10.0 mm/s in 2003 and 2004, respectively. Moreover, canopy surface conductance was lower in dry-hot seasons than in fog-cool and rainy seasons. Canopy surface conductance correlated significantly and positively with leaf area index, but negatively with water vapor pressure deficit. In general, canopy surface conductance was not affected directly by soil water content, but highly depended on soil moisture status when soil water content was below 0.15 m3/m3. Annual total evapotranspiration of this forest ecosystem in dry seasons was lower than that in rainy seasons, which was considered as one of the most important reasons that tropical seasonal rain forest could survive and flourish in Xishuangbanna at limit of water and heat.  相似文献   

10.
西双版纳热带季节雨林水热通量   总被引:5,自引:1,他引:5  
利用西双版纳热带季节雨林2003和2004年常规气象、生物量以及水热通量观测资料,对该林地两年内各能量分量的数值大小和变化规律、能量分配以及水量平衡特征等进行了分析研究。结果表明,2003和2004年净辐射总量分别为3516.4MJ/(m.2a)和3516.6MJ/(m.2a)。在能量分配过程中潜热通量占优势,2003年和2004年的总量分别是相应年份净辐射总量的46%和44%,显热通量则分别只有12%和11%。2003年和2004年林冠传导率均值分别为10.3mm/s和10.0mm/s,其中干热季期间的林冠传导率明显低于雾凉季和雨季。林冠传导率与叶面积指数和空气饱和水汽压差值之间分别呈极显著的正、负线性相关关系;它基本上不受土壤含水量的影响,只是当长期无雨或雨量很小导致土壤含水量低于0.15m3/m3时,林冠传导率才与土壤含水量间存在极显著的相关关系。西双版纳热带雨林2003和2004年的蒸散量分别是663mm和634mm,受浓雾和林冠传导率的综合影响,该森林生态系统干季蒸散量低于雨季,这是西双版纳热带季节雨林能够在水热极限条件下生存并良好发育的重要原因。  相似文献   

11.
Dou J X  Zhang Y P  Yu G R  Zhao S J  Song Q H 《农业工程》2007,27(8):3099-3109
The values and variation characteristics of energy components, their relationship with net radiation and the characteristics of water balance in the forest were analyzed, based on the observation data of energy fluxes, meteorological parameters and biomass in a tropical seasonal rain forest in Xishuangbanna from January 2003 to December 2004. The results show that annual net radiation was 3516.4 MJ/(m2 · a) and 3516.6 MJ/(m2 · a) in 2003 and 2004, respectively, of which 46% and 44% were used in latent heat flux, and 12% and 11% were lost as sensible heat flux. Annual mean canopy surface conductance was 10.3 mm/s and 10.0 mm/s in 2003 and 2004, respectively. Moreover, canopy surface conductance was lower in dry-hot seasons than in fog-cool and rainy seasons. Canopy surface conductance correlated significantly and positively with leaf area index, but negatively with water vapor pressure deficit. In general, canopy surface conductance was not affected directly by soil water content, but highly depended on soil moisture status when soil water content was below 0.15 m3/m3. Annual total evapotranspiration of this forest ecosystem in dry seasons was lower than that in rainy seasons, which was considered as one of the most important reasons that tropical seasonal rain forest could survive and flourish in Xishuangbanna at limit of water and heat.  相似文献   

12.
In north Georgia populations of the soldier beetle, Chauliognathus pennsylvanicus , the length of the elytral spot varies clinally. At the southern end of a 200 km cline the distribution of spot length is unimodal with longer spot lengths predominating while at the northern end of the cline the distribution is bimodal but with shorter spot lengths being more frequent. North of the cline only short elytral spot lengths are observed, while the converse is true south of the cline. The strength of assortative mating on the basis of elytral spot length increases from south to north along the cline, resulting in complete pre-mating isolation between short and long spot length morphs at the north end of the cline. Laboratory mate choice tests indicate that assortative mating in the field is not the result of differential timing of activity or microhabitat choice but rather that it represents a real behavioural preference. Individuals from monomorphic populations on either side of the cline do not mate assortatively in the laboratory, indicating that reproductive isolation has evolved on the cline.  相似文献   

13.
The mountain pine beetle Dendroctonus ponderosae is a native species currently experiencing large-scale outbreaks in western North American pine forests. We sought to describe the pattern of genetic variation across the range of this species, to determine whether there were detectable genetic differences between D. ponderosae occupying different host trees in common localities, and to determine whether there was molecular evidence for a past demographic expansion. Using a combination of amplified fragment length polymorphism (AFLP) and mitochondrial sequencing analyses, we found evidence of genetic structuring among populations that followed a broad isolation-by-distance pattern. Our results suggest that the geographical pattern of gene flow follows the core distribution of the principal D. ponderosae host species, around rather than across the Great Basin and Mojave Deserts. Patterns of haplotype diversity and divergence were consistent with a range-wide population expansion. This signal was particularly pronounced in the northern part of the species' range, where outbreak activity is currently increasing. Using AFLP markers, we were unable to detect significant differences among groups of insects sampled from different host trees in common locations. Incidentally, we found that a large proportion of the polymorphic AFLP markers were gender-specific, occurring only in males. While we did not include these markers in our analyses, this finding warrants further investigation.  相似文献   

14.
通过对热带季节雨林雾凉季和湿热季昼间林窗区域不同热力作用面的热力效应初步分析,指出在西双版纳,不论是雾凉季还是湿热季,热带季节雨林林窗边缘壁面均具有不可忽视的热力作用,且由于受林缘树木的影响,热力效应较强的东侧,北侧林缘壁面最大区域出现位置高于次生林林窗,而强度小于次生林林窗,显示了林窗边缘壁面的热力效应除与太阳高度角,太阳辐射的时间长短和强度有关之外,林窗边缘树木高度也是不可忽视的因子,其结果可为进一步研究林窗小气候形成机制提供研究基础,为研究林窗更新及生物多样性问题提供科学参考。  相似文献   

15.
We investigated geographic color variation of the beetle Phelotrupes auratus in the Kinki region of central Japan using a spectrophotometer. The reflectance spectrum of the dorsal surface of the elytron was measured for beetles collected from 23 sites. We focused on λmax(α), the wavelength at the peak (α peak) between 400 and 700 nm (human visual sensitivity range), for analyses of color variation. In populations distributed on the Kii Peninsula, in the southern part of the Kinki region, average λmax(α) values were lower (480–497 nm) than in populations distributed in the area west of Lake Biwa, the western part of the Kinki region (618–633 nm). For populations distributed in the areas south and southeast of Lake Biwa, a geographic cline of λmax(α) was observed approximately along an east–west transect, with average λmax values varying continuously from 624 to 557 nm. The easternmost populations along this cline had almost the same λmax(α) values as the populations distributed west of Lake Biwa. The coefficient of variation for λmax(α) tended to be larger in populations with intermediate averages than those with lower or higher average values.  相似文献   

16.
In recent years, there have been considerable efforts to restore degraded tropical montane forests through active restoration using indigenous tree species. However, little is known about how these species used for restoration influence other species. In this study, two potential restoration species, Albizia gummifera and Neoboutonia macrocalyx, are investigated with regard to the relationship between their density and the abundance and richness of other plant species. The study was conducted in a degraded forest consisting of disturbed transition zones and secondary forest. Our results show positive relationships between the density of A. gummifera and the abundance of tree seedling and sapling richness in the transition zones and in the secondary forest. Shrub richness was negatively related to the density of A. gummifera. Abundance and richness of tree saplings and shrubs were positively related to N. macrocalyx density both in the transition zones and in the secondary forest. Herb species richness declined with N. macrocalyx density in the transition zones but increased with N. macrocalyx density in the secondary forest. The positive relationships between the density of the two tree species and species richness of other woody species suggest that both A. gummifera and N. macrocalyx can be suitable for active restoration of degraded mountain forests within their natural range.  相似文献   

17.
1. The occurrence and community structure of dung beetle species (Coleoptera: Scarabaeinae) in the faecal deposits of man and some domestic vertebrates varied according to dung type, seasonal conditions and soil type. 2. Of the twenty-four species belonging to six genera, Onthophagus was the prevalent genus and O. ramosellus the most abundant species. 3. Cattle dung was the dominant food type.  相似文献   

18.
Question: Are vines light‐demanding species? Location: Temperate evergreen rain forest of southern Chile (40°39′S, 72°11′W). Methods: In 45 plots of 25 m2 distributed in treefall canopy gaps, secondary forest stands and old‐growth forest (15 plots per light environment), all climbing and non‐supported vines were counted and identified to species level, and canopy openness was quantified using hemispherical photographs. Vine abundance and diversity (species richness and Simpson's index) were compared in the three light environments and similarity between vine communities was estimated using Jaccard's similarity coefficient. We also determined the relationship between light niche breadth and local dominance at the species level. Results: In total there were 2510 vine individuals of 14 species. Canopy openness was significantly different in the three light environments. Species richness, diversity, community composition and density of vines were similar in treefall gaps, secondary and old‐growth forest. Of the seven more common vine species, which accounted for 91% of all vines, three had even distribution, two were more abundant in the shaded understorey, and two had higher density in well‐lit sites. Local dominance of vine species and niche breadth were not significantly associated. Conclusions: Our study in a temperate rain forest questions the widespread notion of vines as pioneer‐like species, which may be a consequence of the abundance of some lianas in disturbed sites of tropical forests. Functional arguments are needed to justify a general hypothesis on light requirements of vines, which constitute a vast group of species.  相似文献   

19.
Aim An area’s ability to support species may be dependent not only on the total amount of available energy it contains but also on energy density (i.e. available energy per unit area). Acknowledging these two aspects of energy availability may increase mechanistic understanding of how increased energy availability results in increased species richness. We studied the relationship between energy density, its variation in space and boreal forest bird species richness and investigated two possible mechanisms: (1) metabolic constraints of organisms, and (2) increased resource availability for specialists. Location Protected areas in Finland’s boreal forest. Methods We tested whether bird species richness was best determined by total energy availability in an area or by energy density and its variation within the area, before and after including bird abundance in the models. We evaluated two main explanatory variables: tree growth reflecting the rate of energy production and tree volume as a measure of biomass. In addition, we modelled individual species’ responses to energy density and its variation, and evaluated the prediction of the metabolic constraints hypothesis that small species are limited by energy density whereas large species are limited by total energy availability in the area. Results Energy density and its variation were good predictors of species richness: together with abundance they explained 84% of variation in species richness (compared with 74% for abundance alone). Pure metabolic constraints were unlikely to explain this relationship. Instead, the mechanism probably involved increased habitat heterogeneity benefiting specialist species. Total energy availability was also an important factor determining species richness but its effect was indirect via abundance. Main conclusions Our results corroborate the importance of energy availability as a driver of species richness in forest bird communities, and they indicate that energy density and its variation in the landscape strongly influence species richness even after accounting for abundance.  相似文献   

20.
针阔叶混交林是我国南亚热带针叶林向地带性常绿阔叶林演替的中间林分类型,为我国南亚地区主要森林类型,发挥着重要的生态系统服务功能。基于树干液流技术和对臭氧浓度的连续监测,评价该森林类型的臭氧吸收特征和能力有着重要的环境生态学意义。对鼎湖山天然针阔叶混交林优势种马尾松(Pinus manssoniana)、锥栗(Castanopsis chinensis)、木荷(Schima superba)和华润楠(Machilus chinensis)在自然环境条件下的臭氧吸收能力进行了分析研究。结果表明:在日尺度上,4个优势树种的冠层气孔对臭氧导度(GO_3)和臭氧吸收通量(FO_3)均呈单峰型曲线,其最大值的时间在干季(10月至竖年3月)比湿季(4月至9月)滞后;季节尺度上,臭氧浓度在湿季达到最大值48.94 n L/L,湿季GO_3、FO_3和年臭氧吸收累积量(accumulative stomatal O_3flux,AFst)均显著高于干季(P 0.01),华润楠的臭氧吸收能力最强,在干季和湿季可分别达1.11 nmol m~(-2)s~(-1)和1.71nmol m~(-2)s~(-1)。随着水汽压亏缺(VPD)增大,优势种GO_3降低。光合有效辐射(PAR)超过1500 umol m~(-2)s~(-1)时,优势树种GO_3和FO_3呈下降趋势。针阔叶混交林的年臭氧吸收累积量超过了保护森林树木所采用的临界阈值,可认为鼎湖山针阔叶混交林受臭氧危害的潜在风险较高。  相似文献   

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