Diversity and similarity of butterfly communities in five different habitat types at Tam Dao National Park, Vietnam

Diversity and similarity of butterfly communities were assessed in five different habitat types (from natural closed forest to agricultural lands) in the mountains of Tam Dao National Park, Vietnam for 3 years from 2002 to 2004. The line transect count was used to record species richness and abundance of butterfly communities in the different habitat types. For each habitat, the number of species and individuals, and indices of species richness, evenness and diversity of butterfly communities were calculated. The results indicated that species richness and abundance of butterfly communities were low in the natural closed forest, higher in the disturbed forest, highest in the forest edge, lower in the shrub habitat and lowest in the agricultural lands. The indices of species richness, evenness and diversity of butterfly communities were low in agricultural lands and natural closed forest but highest in the forest edge and shrub habitats. The families Satyridae and Amathusiidae have the greatest species richness and abundance in the natural closed forest, with a reduction in their species richness and abundance from the natural closed forest to the agricultural lands. Species composition of butterfly communities was different among five different habitat types (40%), was similar in habitats outside the forest (68%) and was similar in habitats inside the forest (63%). Diversity and abundance of butterfly communities are not different between the natural closed forest and the agriculture lands, but species composition changed greatly between these habitat types. A positive correlation between the size of species geographical distribution range and increasing habitat disturbance was found. The most characteristic natural closed forest species have the smallest geographical distribution range.     

甘肃小陇山林区不同生境类型蝶类多样性研究

于2006～2008年对甘肃小陇山林区不同生境类型中蝴蝶多样性进行了调查研究,研究中依据植被的不同将该林区的蝴蝶生境划分为6种类型:人工林、灌木丛和次生林、居民农田、针阔混交林、落叶阔叶林、针叶林。共获得蝴蝶标本5365只,隶属于11科116属210种。计算了6种生境类型中蝶类物种丰富度、相似性系数和多样性指数。不同生境中,灌木丛和次生林蝶类物种的多样性指数、丰富度和个体数量较高,人工林物种多样性指数、丰富度和个体数量较低;人工林与针叶林之间的相似性系数(0.4194)最高,针阔混交林与落叶阔叶林的相似性系数(0.2951)次之,人工林与灌木丛和次生林之间的相似性系数(0.0769)最低,表明各生境之间蝶类相似性系数很低。     

区域变动尺度上不同生境类型及环境因子对西双版纳蝴蝶多样性的影响

【目的】生境类型和环境因子对物种分布和维持具有重要的影响。本研究通过分析不同生境类型对蝴蝶群落多样性及其群落结构影响的差异,以及环境因子对蝴蝶物种丰富度和多度的影响,为区域变动尺度蝴蝶多样性维持机制的研究奠定基础。【方法】于2019年8月和10月,在西双版纳地区采用样线法,调查了天然林、次生林、复合生境、人工林和农田5种生境中蝴蝶的物种,分析了蝴蝶群落多样性、群落结构相似性及物种丰富度和多度与环境因子的关系。【结果】2019年从西双版纳共采集蝴蝶2 226头,隶属于11科98属175种,在西双版纳州级尺度上蝴蝶物种丰富度高于县域尺度。在西双版纳州级尺度上,蝴蝶的物种丰富度和多度在5种生境间存在显著差异,而在县域尺度上,物种丰富度、多度和Chao 1物种丰富度估计值没有一致性规律。群落结构相似性结果显示,在西双版纳州级尺度上,蝴蝶群落结构在不同生境类型间存在极显著差异,在县域尺度上,仅勐腊区域蝴蝶群落结构在不同生境类型间存在显著差异。蝴蝶物种丰富度和多度不仅受到生境类型的影响,还受到温度、年均降水和海拔的影响。【结论】本研究结果表明,在区域变动尺度上,生境类型对西双版纳蝴蝶的多样性的影响较大,而温度、年均降水和海拔是维持蝴蝶物种多样性的重要因素。这些发现对当前人类导致的生境丧失和气候变化时代生物多样性的保护具有重要意义。     

小兴安岭凉水自然保护区蝶类多样性

2012—2013年选取原始阔叶红松林、人工林、天然次生林和灌丛草甸4种典型植被生境,对小兴安岭凉水自然保护区的蝶类进行了系统研究。共捕获蝶类1438头,分属7科47属76种,4种植被生境中蝶类群落优势类群均为蛱蝶科,不同生境蝶类群落相似性与生境植被类型密切相关。计算分析了4种植被生境中蝶类多样性指数、物种丰富度、优势度指数、均匀度指数和种-多度关系,结果表明:3种森林生境蝶类多样性大于灌丛草甸,原始阔叶红松林蝶类具有最高的多样性指数、较高的物种丰富度、均匀度指数以及最低的优势度指数,种-多度分布为对数正态分布,说明环境质量优越,最适合蝶类生存和繁衍;灌丛草甸蝶类的多样性指数、物种丰富度和均匀度指数均为最低,而优势度指数最高,种-多度分布为对数级数分布,反映植物群落结构较单一,适合各种蝶类生存和繁衍的资源不足;天然次生林蝶类多样性指数、物种丰富度高于人工林,均匀度小于人工林,但前者种-多度分布为对数级数模型,后者为对数正态模型,说明在封山育林状态下,对森林植被组成进行适当合理的干扰,有利于森林的健康发展     

西双版纳热带植物园蝴蝶的多样性及变化

中国科学院西双版纳热带植物园（简称“版纳植物园”）保存着上万种植物,且生境多样,具有较高的蝴蝶多样性。本研究选择三类代表性生境：片段化雨林、次生林和专类园,聚焦于环境指示物种蝴蝶这一类群,通过样线法系统调查一年内蝴蝶多样性及其变化。观测结果显示：蝴蝶在版纳植物园内全年发生,共调查到其成虫5科126属218种6 015头,其中蛱蝶科多样性最高。蝴蝶种类及数量随月动态变化,生境间有差异,7-8月种类和数量达到最高峰;1月种类最少,而5-6月数量最低;每月均出现的种类仅有12种,绝大部分种类分散发生于不同月份。影响蝴蝶群落多样性的气候因子中,月最高温显著影响蝴蝶群落的物种丰富度和数量,月最低温显著影响物种丰富度、香农多样性和辛普森多样性,月平均温仅显著影响香农多样性。在版纳的三个典型季节中蝴蝶多样性存在差异,雨季物种丰富度最高,干热季香农和辛普森指数最高;雨季和雾凉季蝴蝶群落组成差异大,仅雾凉季与干热季的蝴蝶群落呈现中等程度相似。此外,在片段化雨林、次生林和专类园这3种不同生境中,蝴蝶群落组成也存在差异,蝴蝶物种丰富度和香农指数在次生林中最高,而辛普森指数则是片段化雨林最高;仅次生林与片段化雨林的蝴蝶群落呈现出中等程度相似。本研究揭示了版纳植物园蝴蝶群落的种类组成与月动态变化规律,并明确了不同季节和生境中蝴蝶群落的多样性变化,可为区域蝴蝶多样性观测及保护提供参考依据。     

Dung beetle assemblages in primary forest and disturbed habitats in a tropical dry forest landscape in western Mexico

Dung beetles (Scarabaeinae) are conspicuous components in most terrestrial ecosystems, performing important ecological functions and services. Being sensitive to several types of disturbance, they have been successfully used as indicators of habitat change. Dung beetle communities in tropical rainforests have been well studied, but considerably less information is available for tropical dry forests. In this study I sampled dung beetles in two undisturbed habitats, deciduous forest and semideciduous forest, and two disturbed habitats, secondary forest and open area habitat, in the Chamela-Cuixmala region of western Mexico. Dung beetle species with high indicator value for each habitat were identified. Beetle abundance, observed species richness and estimated species richness were similar in the three forest habitats, but significantly lower in the open area habitat. A more detailed analysis of species-specific abundances in the three forest habitats revealed some differences. Transects of one of the undisturbed habitats, the deciduous forest, were more similar to the non-adjacent transects of disturbed secondary forest, than to the adjacent undisturbed semideciduous forest transects. Unlike studies in other tropical sites that have found a decrease in equitability in Scarabaeinae assemblages between undisturbed forest and disturbed habitat (particularly open habitats), in the Chamela-Cuixmala region all four habitats showed similar low equitability in community structure, with two or three very dominant species.     

Species‐habitat relationships and ecological correlates of butterfly abundance in a transformed tropical landscape

Tropical butterfly conservation strategies often focus on total and/or common species richness to assess the conservation value of a patch or habitat. However, such a strategy overlooks the unique dynamics of rare species. We evaluated the species‐habitat relationships of 209 common, intermediate, and rare butterfly species (including morphospecies) across four habitat types (mature, degraded, or fragmented forest, and urban parks) and two patch sizes (<400 ha, ≥400 ha) in Singapore. Common species richness was consistent across habitat types. Intermediate species richness declined by more than 50 percent in urban parks (relative to all forest habitats), and rare species richness was reduced by 50 percent in degraded and fragmented forest and by 90 percent in urban parks (relative to mature forest). Large patches had comparable overall richness to small patches, but they supported more rare species and three times as many habitat‐restricted species over a similar area. Importantly, a number of rare species were confined to single small patches. Mixed‐effects regression models were constructed to identify habitat and ecological/life history variables associated with butterfly abundance. These models revealed that species with greater habitat specialization, rare larval host plants, few larval host plant genera, and narrow global geographic ranges were more likely to be rare species. Overall, these results demonstrate that the richness of habitat‐restricted and rare species do not follow the same spatial distribution patterns as common species. Therefore, while conserving mature forests is key, effective butterfly conservation in a transformed landscape should take into account rare and habitat‐restricted species.     

Ecology of pollination in a tropical Venezuelan savanna

Pollination modes ecology of a total of 164 plant species was evaluated according to habitats and plant life forms in the Venezuelan Central Plain. Frequency distribution of nine pollination modes showed that, at the community level bee pollination (38.6%) was dominant. Butterfly (13.9%), fly (12.7%), and wasp (10.8%) pollination were the second most frequent. Moth (6.2%) and wind (10.4%) pollination occurred with similar frequency, and the least common were bird (3.1%), beetle (2.3%) and bat (1.9%) pollination. There was a significant interaction effect indicating that pollination mode was affected by the type of habitat. Bee pollination was the most common pollination mode in all habitats with butterfly, fly and wasp pollination being secondary for forest and forest-savanna transition; and butterfly, wasp, wind and fly pollination being secondary for savanna. Wind, butterfly and fly pollination were found in disturbed areas as secondary pollination modes. Pollination modes were significantly associated and affected by life forms. Bee pollination was dominant in all life forms with wasp, butterfly and fly pollination being the secondary for trees, shrubs, and lianas; and butterfly and wind pollination being the secondary for herbaceous species. The number of pollination modes (richness) among life forms ranged between four and nine for epiphytes and perennial herbs respectively. The highest values of diversity indexes among life forms were found in trees and shrubs. The richness and diversity indices of pollination modes were statistically higher for more structured habitats, forest and forest-savanna transition, than herbaceous habitats, savanna and disturbed areas, which is associated with the highest values of diversity indexes in trees and shrubs. Equitability was higher for forest and disturbed areas than forest-savanna transition and savanna. The results of comparative richness, equitability, diversity indices, and the frequency distribution of pollination modes of 19 samples from tropical and temperate communities indicated that richness of pollination modes may be different between tropical and temperate communities. The proportion of each pollination mode suggests four grouping: (1) rain forests and their strata, (2) grassland savanna, and associated disturbed areas, (3) temperate communities, and (4) the most heterogeneous group, contained mostly neotropical communities, including the four habitats of the Venezuelan Central Plain. The frequency of pollination modes, richness, diversity and equitability of communities, habitats, successional stages, and vegetation strata varies with respect to geography, vegetation structure, and plant species richness.     

Habitat conversion and galling insect richness in tropical rainforests under mining effect

Human-induced habitat change is the main cause of species loss and can have severe effects on plant communities and the associated herbivore fauna. In this study, we investigated the effects of habitat conversion due to mining on communities of galling insects in areas of tropical rainforest in the Brazilian Amazon. We sampled galling insects in the Floresta Nacional de Saracá Taquera, Pará, Brazil, where forest plateaus are used by the Mineração Rio do Norte Group to extract bauxite. Our results show that human-induced habitat change via mining activities increased the local species richness of galling insects. We also found that after impact there was greater species richness of galling insects closer to the forest edge than in the forest interior. Changes in plant physiology and in the diversity of natural enemies in human-modified habitats, along with the endophagous life-form, might account for the high incidence of galling in human-disturbed habitats. This result highlights the importance of understanding how different insect groups respond to human activities, since such idiosyncrasies might have profound effects on the species’ patterns of ecological interactions and in the outcomes of those interactions.     

Importance of local habitat conditions and past and present habitat connectivity for the species richness of grassland plants and butterflies in power line clearings

Agricultural intensification has caused drastic declines in the area and species richness of semi-natural grasslands across Europe. Novel habitats, such as power line clearings, provide alternative habitats and niches for grassland species, and might therefore mitigate these declines. However, it is not fully understood which environmental factors determine the occurrence of grassland species in the clearings. Identifying the most important drivers for grassland species occurrence would help understand the value of the clearings for grassland conservation and target enhanced management into clearings with most potential as grassland habitat. We studied the effects of local environmental conditions, and past and present connectivity to semi-natural grasslands, on the species richness of grassland plants and butterflies in 43 power line clearings in Finland. The results of generalized linear models and hierarchical partitioning showed that increasing time since clear-cut and amount of clearing residue decreased the species richness of both species groups, while the cover of mesic habitats increased it. However, the two species groups showed also divergent responses. Present-day local environmental conditions appeared to be the sole driver of grassland butterfly species richness, whereas the richness of grassland plants was related both to current conditions and historical connectivity to grasslands in 1870–1880s. This suggests the presence of an extinction debt in the studied grassland plant communities, emphasizing the need for enhanced management to increase suitable grassland habitat in the clearings. This would diminish the potential future losses of grassland plant species in the clearings and create valuable habitat for grassland butterflies as well.     

Species diversity in vertical, horizontal, and temporal dimensions of a fruit-feeding butterfly community in an Ecuadorian rainforest

To test the hypotheses that fruit-feeding nymphalid butterflies are randomly distributed in space and time, a community of fruit-feeding nymphalid butterflies was sampled at monthly intervals for one year by trapping 6690 individuals of 130 species in the canopy and understory of four forest habitats: primary, higraded, secondary, and edge. The overall species abundance distribution was well described by a lognormal distribution. Total species diversity (γ-diversity) was partitioned into additive components within and among community subdivisions (α-diversity and β-diversity) in vertical, horizontal and temporal dimensions. Although community subdivisions showed high similarity (1 —β-diversity/γ-diversity), significant β-diversity existed in each dimension. Individual abundance and observed species richness was lower in the canopy than in the understory. However, rarefaction analysis and species accumulation curves revealed that canopy had higher species richness than understory. Observed species richness was roughly equal in all habitats, but individual abundance was much greater in edge, largely due to a single, specialist species. Rarefaction analysis and species accumulation curves showed that edge had significantly lower species richness than all other habitats. Samples from a single habitat, height and time contained only a small fraction of the total community species richness. This study demonstrates the feasibility, and necessity, of large-scale, long-term sampling in multiple dimensions for accurately measuring species richness and diversity in tropical forest communities. We discuss the importance of such studies in conservation biology.     

Effects of disturbances on scuttle flies (Diptera: Phoridae) in Pine Forests

I investigated the ecological consequences of disturbances (anthropogenic and natural) on the scuttle fly communities in four large Pine Forests in Poland. I used data on 17,547 male individuals representing 183 species. Communities found in pine plantations (established in clear-cut areas) and in differently treated post-windstorm (with windthrow logs being left or removed) were less diverse than those found in old-growth forest. The communities recorded in the same habitat types in different forest complexes (ca. 300 km apart) were found to display greater similarity than those recorded on adjacent plots in a given forest (ca. 1 km apart), but covering different habitats. The species-specific preference for habitats after disturbances (clear-cuts and post-windstorm areas) was highly correlated between the forests. The abundance of the species with saprophagous larvae was distinctly higher in the disturbed areas than in the old-growth stands. Also, the body length of the scuttle flies was significantly related to their preference for disturbed or undisturbed habitats: smaller species preferred clear-cuts and post-windstorm areas, whereas larger species were related to intact stands.     

Conservation value of degraded habitats for forest birds in southern Peninsular Malaysia

Clearance of tropical forest for agricultural purposes is generally assumed to seriously threaten the survival of forest species. In this study, we quantified the conservation value, for forest bird species, of three degraded habitat types in Peninsular Malaysia, namely rubber tree plantations, oil palm plantations, and open areas. We surveyed these degraded habitats using point counts to estimate their forest bird species richness and abundance. We assessed whether richness, abundance, and activities of different avian dietary groups (i.e. insectivores and frugivores) varied among the habitats. We identified the critical habitat elements that accounted for the distribution of forest avifauna in these degraded habitats. Our results showed that these habitats harboured a moderate fraction of forest avifauna (approximately 46–76 species) and their functions were complementary (i.e. rubber tree plantations for moving; open habitats for perching; shrubs in oil palm plantations for foraging). In terms of species richness and abundance, rubber tree plantations were more important than oil palm plantations and open habitats. The relatively high species richness of this agricultural landscape was partly due to the contiguity of our study areas with extensive forest areas. Forecasts of forest-species presence under various canopy cover scenarios suggest that leaving isolated trees among non-arboreal crops could greatly attract relatively tolerant species that require tree canopy. The conservation value of degraded habitats in agricultural landscapes seems to depend on factors such as the type of crops planted and distance to primary forest remnants.     

Butterfly diversity and historical land cover change along an altitudinal gradient

Land cover and climate change are both major threats for biodiversity. In mountain ecosystems species have to adapt to fragmented habitats and harsh environmental conditions but so far, altitudinal effects in combination with land cover change have been rarely studied. The objective of this study was to determine the effects of altitude and historical land cover change on butterfly diversity. We studied species richness patterns of butterflies occuring in wetlands and other open habitats along an altitudinal gradient in a low mountain region (340–750 m a.s.l., Bavaria, Germany) with drastic loss of open habitats within the last 40–60 years. We recorded in 27 sites a total of 4,523 individuals of 49 butterfly species and five species of burnet moths. Species richness peaked at mid elevation and increased with patch size. Land cover change was most pronounced at high altitudes, but neither current open habitats, nor the historical loss of open habitats affected the species richness of butterflies. Neither open land specialized butterflies nor generalist and forest species were significantly affected by the loss of open habitats. However, increasing forest area in high altitudes reduces possible refuge open habitats for butterflies at their thermal distribution limits. This could lead to extinction of such butterfly species when temperatures further rise due to global warming.     

Effects of forest degradation on butterfly communities in the Gwangneung Forest

This study was carried out to clarify the response of butterfly communities on forest degradation in the Gwangneung Forest, Korea. We monitored butterfly communities with varying degrees of human activities by conducting a line transect twice a month in 2011. A total of 70 species and 4676 individuals of butterflies were observed in four sites: natural forest (NR), two plantation forests, and the Korean National Arboretum (AR). The result on niche breadth, habitat breadth and habitat type of butterfly was not consistent with our predictions. Species richness of habitat type was only significantly different between NF and AR. Species diversity was significantly different among sites. Butterfly diversity associated with landscape patterns based on aerial photographs supported a mosaic concept. A forest management plan to conserve butterfly diversity in forests is necessary to maintain various habitats and to ensure that grasslands are protected.     

麦积山风景区不同生境类型蝶类的多样性

于2003~2004年对麦积山地区不同生境类型中蝴蝶多样性进行调查研究。依据海拔高度、气候、土壤和植被的不同将该地区的蝴蝶生境划分为3种类型:林缘山地、森林林地、裸岩。共收集蝴蝶3950只,隶属8科43属64种。计算了3种生境类型中蝶类物种丰富度、相似性系数、多样性指数。其中,蝴蝶物种丰富度由大到小为森林林地(8·8359)>林缘山地(6·1442)>裸岩(1·4711),物种多样性指数由大到小为森林林地(H'=1·4068)>裸岩(H'=0·9746)>林缘山地(H'=0·9201);森林林地和林缘山地的相似性系数最高(0·2221),其次是林缘山地和裸岩(0·0869),森林林地和裸岩相似性系数最低(0·0656)。     

青海玉树高原不同生境类型蝶类群落结构与多样性

2016年和2017年的5—8月,在玉树市选取森林、灌木、高寒灌丛、高寒草甸草原和裸岩5种生境进行蝴蝶种类资源和群落多样性的调查,共记录到蝶类个体数1580头,62种,隶属于7科40属。其中古北界19种,占总种数的30%,东洋界2种,占总种数的3%,两界共有种(广布种) 41种,占总种数的67%。蛱蝶科(535只)个体数量最多,占蝶类个体总数的34%。计算并分析了5种生境中蝴蝶多样性指数(H')、优势度指数(D)、物种丰富度指数(R)、均匀度指数(J)和相似性系数(I),结果表明:灌木生境具有最高的多样性指数,较高均匀度指数和物种丰富度指数以及最低的优势度指数;高寒草甸草原蝶类的多样性指数、均匀度指数、物种丰富度指数均为最低,而优势度指数最高。     

A comparison of seed banks across a sand dune successional gradient at Lake Michigan dunes (Indiana,USA)

In habitats where disturbance is frequent, seed banks are important for the regeneration of vegetation. Sand dune systems are dynamic habitats in which sand movement provides intermittent disturbance. As succession proceeds from bare sand to forest, the disturbance decreases. At Indiana Dunes National Lakeshore, we examined the seed banks of three habitat types across a successional gradient: foredunes, secondary dunes, and oak savanna. There were differences among the types of species that germinated from each of the habitats. The mean seed bank density increased across the successional gradient by habitat, from 376 to 433 to 968 seeds m⁻², but with foredune and secondary dune seed bank densities being significantly lower than the savanna seed bank density. The number of seeds germinated was significantly correlated with soil organic carbon, demonstrating for this primary successional sequence that seed density increases with stage and age. The seed bank had much lower species richness than that of the aboveground vegetation across all habitats. Among sites within a habitat type, the similarity of species germinated from the seed banks was very low, illustrating the variability of the seed bank even in similar habitat types. These results suggest that restoration of these habitats cannot rely on seed banks alone.     

The conservation value of South East Asia's highly degraded forests: evidence from leaf-litter ants

South East Asia is widely regarded as a centre of threatened biodiversity owing to extensive logging and forest conversion to agriculture. In particular, forests degraded by repeated rounds of intensive logging are viewed as having little conservation value and are afforded meagre protection from conversion to oil palm. Here, we determine the biological value of such heavily degraded forests by comparing leaf-litter ant communities in unlogged (natural) and twice-logged forests in Sabah, Borneo. We accounted for impacts of logging on habitat heterogeneity by comparing species richness and composition at four nested spatial scales, and examining how species richness was partitioned across the landscape in each habitat. We found that twice-logged forest had fewer species occurrences, lower species richness at small spatial scales and altered species composition compared with natural forests. However, over 80 per cent of species found in unlogged forest were detected within twice-logged forest. Moreover, greater species turnover among sites in twice-logged forest resulted in identical species richness between habitats at the largest spatial scale. While two intensive logging cycles have negative impacts on ant communities, these degraded forests clearly provide important habitat for numerous species and preventing their conversion to oil palm and other crops should be a conservation priority.     

长白山北坡不同海拔及干扰程度下访花食蚜蝇群落的差异

本研究采用垂直面取样法,对中国长白山北坡不同海拔及干扰程度下访花食蚜蝇群落的物种组成、多度、丰富度及多样性进行了调查研究。我们选择了不同垂直带的两个样地,分别位于800~1 100 m和1 750 ~2 150 m;每个样地选取3种生境类型,每一生境类型采样面积为20 m×20 m。252组调查数据表明,共采到访花食蚜蝇42种2 540个体。不同海拔生境访花食蚜蝇的组成、多度、丰富度及多样性的差异分析结果表明: 低海拔样地内不同生境访花食蚜蝇的群落相似性高于高海拔样地;低海拔样地访花食蚜蝇的多度高于高海拔样地,而物种丰富度低于高海拔样地;不同生境类型访花食蚜蝇多样性指数存在差异,但高海拔样地与低海拔样地多样性差异不显著;过渡林生境（岳桦林带）与次生林生境（针阔混交林带Ⅱ）中访花食蚜蝇的多样性较高。保护珍稀植物物种的人工植物花园访花食蚜蝇多样性仅次于过渡林生境（岳桦林带）与次生林生境（针阔混交林带Ⅱ）,保护作用显著。