Riqueza do Cerrado em Unidade de Conservação: uma análise da diversidade e estrutura arbórea no Parque Nacional da Chapada dos Guimarães - Mato Grosso

We analyzed species diversity of arbor forests and its relationship with spatial structure and soil factors at different successional stages of Tianmu Mountain National Nature Reserve in Zhejiang Province, including conife-rous and broad-leaved mixed forest and evergreen broad-leaved forest. The results showed that as the coniferous and broad-leaved mixed forest successionally advanced to the evergreen broad-leaved forest, the number of species increased from 51 to 62. In the top 10 species ranked by importance value, the proportion of Fagaceae species increased from 27.7% to 42.3%. Simpson index and Pielou evenness index differed significantly at different succession stages, decreasing from 0.79 to 0.77 and 0.91 to 0.86. In the coniferous and broad-leaved mixed forest stage, competition index was significantly positively correlated with Shannon index and species richness. Complete mingling was significantly positively correlated with Simpson index, Shannon index, and Pielou evenness index. Aggregation index was significantly negatively correlated with Simpson index, Shannon index, and species richness. Hydrolytic nitrogen and available potassium were significantly positively correlated with Pielou evenness index and significantly negatively correlated with species richness. In the evergreen broad-leaved forest stage, aggregation index was significantly negatively correlated with Shannon index and species richness. Complete mingling was significantly positively correlated with Simpson index, Shannon index, and Pielou evenness index. Shannon index and species richness were significantly negatively correlated with hydrolytic nitrogen and significantly positively correlated with available phosphorus. Simpson index, Shannon index, and species richness were significantly positively correlated with organic matter content. Spatial structure explained more variations of species diversity than soil factors at different successional stages. Aggregation index and complete mingling were the main spatial structure factors affecting species diversity. In conclusion, we recommended to focus on regulating spatial structure and to adjust soil physicochemical properties according to the succession stage to protect species diversity of arbor forests in different succession stages in Tianmu Mountains.

Vertical distribution of benthic diatoms in a large reservoir (Alqueva, Southern Portugal) during thermal stratification

SUMMARY1. During the spring of 1992, fifty‐two quantitative diatom samples were collected from twenty‐eight rivers located in the Tokyo Metropolitan area, Japan, to study the response of the diatom assemblages to water pollution (assessed using physical and chemical data determined monthly from April 1987 to March 1992).2. Species composition was analysed by means of biotic indices (Pantle and Buck's saprobic index) and multivariate analyses [two‐way indicator species analysis (TWINSPAN) for classification and canonical correspondence analysis (CCA) for ordination]. Species‐abundance relationships were analysed using diversity indices (species richness, Shannon's diversity index and Pielou's evenness index) and rank‐abundance patterns (rank‐abundance curves).3. CCA revealed two major gradients. The first corresponded to organic pollution and eutrophication. The second corresponded to variables related to geographical location. Four main station groups were determined by TWINSPAN. The location of the indicator species of groups 1–3 along the CCA axis 1 is consistent with their known pollution tolerance characteristics. Indicator species for group 4 had larger scores on CCA axis 2, and are representative of brackish water environments.4. Species richness tended to be higher in the intermediate range of water pollution. Pielou's evenness index and Shannon's diversity index followed the same tendency but only weakly.5. The rank‐abundance patterns of diatom assemblages were more or less constant in all stations. The curves were very similar in shape, differing only in length and gradient (directly related to species richness and evenness, respectively).6. The results of this study indicate that the response of diatom assemblages to environmental change can be observed in species compositional variation. Multivariate analyses and pollution indices revealed this response and are to be preferred to species diversity measures.

三工河流域琵琶柴群落特征与土壤因子的相关分析

The fish fauna diversity and distribution patterns were investigated in the Rana stream situated in the Mandi district, Himachal Pradesh, India. Given the considerable variations in altitude and climatic conditions within the study area, a stratified systematic sampling approach was adopted. The stream was stratified into two zones, upstream and downstream, based on the altitudinal gradient. A total of five fish species were identified, representing 4 genera and 2 orders, namely Cypriniformes and Channiformes. Cypriniformes emerged as the predominant order between the two. The Spearman correlation between fish species and selected abiotic parameters of stream water was examined. Several diversity indices, including Simpson's index, Simpson's diversity index, the Shannon index of diversity, Pielou's evenness index, and Margalef's richness index, were employed to evaluate fish diversity in the stream. The Water Quality Index (<i>WQI</i>) values varied from 49.65 to 55.14, representing that water quality spanning from «good» to «poor». Species diversity was found to be higher in the downstream altitudinal zone compared to the upstream zone. Similarly, microhabitat pools exhibited greater species diversity. It has been found that the low gradient and slow current velocity in downstream locations leading to increased nutrient deposition in deep pools thereby favoured higher fish species abundance.

弃管杉木林杉木数量与群落物种多样性间的关系

于2008-2009年按照季节调查了西藏尼洋河浮游植物群落的组成、丰度和多样性,并运用多元统计方法定量分析了浮游植物的空间和季节变化特征及其与主要环境因子之间的关系.结果显示,尼洋河浮游植物共计7门29科48属,其中硅藻为优势浮游藻类.浮游植物Shannon-Wiener多样性指数(Pielou均匀度指数)在尼洋河中游(尼洋河下游)最高,其他河段呈下降趋势,符合中间高度膨胀假说.尼洋河沿程浮游植物的总丰度、物种丰富度、Shannon-Wiener多样性指数以及Pielou均匀度指数不存在显著差异,夏季的浮

Based on community investigation data from grasslands on two different soil parent material types (loess and sand parent materials) and under three human utilization modes in the Saihan Ullah Reserve, we calculated human disturbance index (HDI) and biodiversity indices and analyzed the interactions between species diversity and degradation levels. The results showed that degradation status varied across different soil parent material types and human utilization modes, and that degradation levels of loess and sand parent materials both increased with the enhancement of human utilization intensification. HDI of loess parent material grasslands (mean value of 1.21) was lower than sand parent material grasslands (mean value of 1.48) in the same human utilization. Biodiversity indices declined with soil sandy degree and the utilization intensification. The mean values of Margarlef richness index, Shannon diversity index, Simpson dominance index and Pielou evenness index were between 1.57-4.27, 1.16-2.39, 0.76-0.87, and 0.71-0.80, respectively. The Margalef richness index, Shannon diversity index and Simpson dominance index decreased with increasing HDI, while Pielou evenness index increased. Overgrazing could lead to serious threat on both grasslands with soil parent material types, and the optimum utilization mode of loess and sand parent material grasslands were enclosure with mowing and seasonal grazing. In the future works of biodiversity conservation, it is important to consider the influence of both different soil patent material and human utilization modes of grassland. It is urgent to develop different utilization modes for grassland under different soil parent material types, which would enhance the matchness of grassland restoration and management with local conditions.

连作苹果园土壤真菌的T-RFLP 分析

Species diversity is a crucial index used to evaluate the stability and complexity of forest ecosystems. Studying the relationship between stand structure and understory herbaceous plants species diversity is useful for managers to formulate the best forest structure optimization method with the goal of improving herbaceous species diversity. In this research, Platycladus orientalis plantations in Beijing were taken as the research object. Pearson’s correlation analysis was used to explore the single-factor correlation between stand structure and understory herbaceous plants species diversity; furthermore, a typical correlation analysis and multiple linear regression were used to explore the multi-factor correlation and analyze the dominant stand structure parameters affecting understory herbaceous plants species diversity. In the range of stand structures studied, the results showed that canopy density was negatively correlated with the Shannon–Wiener index and Simpson index (p < 0.01), and tree density was negatively correlated with the Shannon–Wiener index (p < 0.05). In terms of stand spatial structure, the mingling degree was positively correlated with the Shannon–Wiener index, Simpson index, Margalef richness index and Pielou evenness index (p < 0.05), while the uniform angle was negatively correlated with the Pielou evenness index (p < 0.05). The correlation coefficient of the first group of typical variables in the typical correlation analysis was 0.90 (p < 0.05); from this group of typical variables, it can be concluded that canopy density is the most influential indicator affecting the comprehensive index of understory herbaceous plants species diversity, with a load of −0.690, and the Shannon–Wiener index and Simpson index are the most responsive indicators of changes in the comprehensive index of stand structure, with loads of 0.871 and 0.801, respectively. In the process of the management of Platycladus orientalis plantations under a low altitude, south slope, thin soil layer and hard soil parent material, in order to improve the herbaceous species diversity, the canopy density of the overstory and tree density should be appropriately reduced. Additionally, it is necessary to regulate the horizontal spatial structure of stands. When the trees are randomly distributed and the mingling degree is high, the species diversity of herbs can be increased.

We studied the effect of many years of streptomycin use in apple orchards on the proportion of phyllosphere bacteria resistant to streptomycin and bacterial community structure. Leaf samples were collected during early July through early September from four orchards that had been sprayed with streptomycin during spring of most years for at least 10 years and four orchards that had not been sprayed. The percentage of cultured phyllosphere bacteria resistant to streptomycin at non-sprayed orchards (mean of 65%) was greater than at sprayed orchards (mean of 50%) (P = 0.0271). For each orchard, a 16S rRNA gene clone library was constructed from leaf samples. Proteobacteria dominated the bacterial communities at all orchards, accounting for 71 of 104 OTUs (determined at 97% sequence similarity) and 93% of all sequences. The genera Massilia, Methylobacterium, Pantoea, Pseudomonas, and Sphingomonas were shared across all sites. Shannon and Simpson’s diversity indices and Pielou’s evenness index were similar among orchards regardless of streptomycin use. Analysis of Similarity (ANOSIM) indicated that long-term streptomycin treatment did not account for the observed variability in community structure among orchards (R = −0.104, P = 0.655). Other variables, including time of summer, temperature and time at sampling, and relative distance of the orchards from each other, also had no significant effect on bacterial community structure. We conclude that factors other than streptomycin exposure drive both the proportion of streptomycin-resistant bacteria and phylogenetic makeup of bacterial communities in the apple phyllosphere in middle to late summer.

Rangelands cover around half of the planet’s land mass and provide vital ecosystem services to over a quarter of humanity. The Himalayan rangelands, part of a global biodiversity hotspot is among the most threatened regions in the world. In rangelands of many developing nations policies banning grazing in protected areas is common practice. In 1998, the Indian state of Sikkim, in the Eastern Himalaya, enacted a grazing ban in response to growing anthropogenic pressure in pastures and forests that was presumably leading to degradation of biodiversity. Studies from the region demonstrate the grazing ban has had some beneficial results in the form of increased carbon stocks and regeneration of some species of conservation value but the ban also resulted in negative outcomes such as reduced household incomes, increase in monocultures in lowlands, decreased manure production in a state that exclusively practices organic farming, spread of gregarious species, and a perceived increase in human wildlife conflict. This paper explores the impact of the traditional pastoral system on high elevation plant species in Lachen valley, one of the few regions of Sikkim where the grazing ban was not implemented. Experimental plots were laid in along an elevation gradient in grazed and ungrazed areas. Ungrazed areas are part of pastures that have been fenced off (preventing grazing) for over a decade and used by the locals for hay formation. I quantified plant species diversity (Species richness, Shannon index, Simpson diversity index, and Pielou evenness index) and ecosystem function (above ground net primary productivity ANPP). The difference method using movable exlosure cages was used in grazing areas to account for plant ANPP eaten and regrowth between grazing periods). The results demonstrate that grazing significantly contributes to greater plant species diversity (Species richness, Shannon index, Simpson diversity index, and Pielou evenness index) and ecosystem function (using above ground net primary productivity as an indicator). The multidimensional scaling and ANOSIM (Analysis of Similarities) pointed to significant differences in plant species assemblages in grazed and ungrazed areas. Further, ecosystem function is controlled by grazing, rainfall and elevation. Thus, the traditional transhumant pastoral system may enhance biodiversity and ecosystem function. I argue that a complete restriction of open grazing meet neither conservation nor socioeconomic goals. Evidence based policies are required to conserve the rich and vulnerable biodiversity of the region.

Rangelands cover around half of the planet's land mass and provide vital ecosystem services to over a quarter of humanity. The Himalayan rangelands, part of a global biodiversity hotspot is among the most threatened regions in the world. In rangelands of many developing nations policies banning grazing in protected areas is common practice. In 1998, the Indian state of Sikkim, in the Eastern Himalaya, enacted a grazing ban in response to growing anthropogenic pressure in pastures and forests that was presumably leading to degradation of biodiversity. Studies from the region demonstrate the grazing ban has had some beneficial results in the form of increased carbon stocks and regeneration of some species of conservation value but the ban also resulted in negative outcomes such as reduced household incomes, increase in monocultures in lowlands, decreased manure production in a state that exclusively practices organic farming, spread of gregarious species, and a perceived increase in human wildlife conflict. This paper explores the impact of the traditional pastoral system on high elevation plant species in Lachen valley, one of the few regions of Sikkim where the grazing ban was not implemented. Experimental plots were laid in along an elevation gradient in grazed and ungrazed areas. Ungrazed areas are part of pastures that have been fenced off (preventing grazing) for over a decade and used by the locals for hay formation. I quantified plant species diversity (Species richness, Shannon index, Simpson diversity index, and Pielou evenness index) and ecosystem function (above ground net primary productivity ANPP). The difference method using movable exlosure cages was used in grazing areas to account for plant ANPP eaten and regrowth between grazing periods). The results demonstrate that grazing significantly contributes to greater plant species diversity (Species richness, Shannon index, Simpson diversity index, and Pielou evenness index) and ecosystem function (using above ground net primary productivity as an indicator). The multidimensional scaling and ANOSIM (Analysis of Similarities) pointed to significant differences in plant species assemblages in grazed and ungrazed areas. Further, ecosystem function is controlled by grazing, rainfall and elevation. Thus, the traditional transhumant pastoral system may enhance biodiversity and ecosystem function. I argue that a complete restriction of open grazing meet neither conservation nor socioeconomic goals. Evidence based policies are required to conserve the rich and vulnerable biodiversity of the region.

Present study was conducted to determine the propagation and biodiversity of corals on artificial reefs at Teluk Kalong and Pasir Akar, Malaysia to check the feasibility of artificial reef to rehabilitate natural reef ecosystems and to provide artificial habitat for marine organisms. Two types of artificial reef deployed in these areas were Dome Reef and EnviroReef which were developed by the Dorken Company. Based on the results obtained, coral distribution was higher at Pasir Akar compared to Teluk Kalong. The Shannon diversity index (H’) and evenness index (EH’) of coral at Teluk Kalong were 0.6425 and 0.1766, respectively while the Shannon diversity index (H’) and Pielou evenness index (EH’) of coral at Pasir Akar were 1.7410 and 0.3247, respectively. Overall, 2 species were found and identified at Teluk Kalong and 10 species were at Pasir Akar with Seriatopora hystrix as the dominant species at both the stations. Coral distribution was higher on Dome Reef compared to EnviroReef. The diversity index (H’) and Pielou evenness index (EH’) of EnviroReef were 0.5359 and 0.1284 respectively while it was 2.2192 and 0.4274, respectively in Dome Reef. A total of 3 and 9 species were found and identified from the EnviroReef and Dome Reef, respectively with Seriatopora hystrix being the dominant in both the reef structures. We conclude that both artificial reefs structures were suitable as habitat for coral propagation.

The present study aimed to assess the effects of organic farming in comparison with conventional on plant composition, plant cover (%), diversity [species richness, Shannon, Simpson, and evenness (Pielou's) indexes] and investigate and describe the relations among plant species richness, plant cover, indexes, and soil parameters (pH and temperature) in olive grove ecosystems during the winter. Organic olive groves had significantly greater values of cover, species richness, and Shannon and Simpson indexes than the conventional ones. Plant species richness was positively correlated to plant cover and Shannon and Simpson indexes but negatively correlated to evenness index for both farming system. Finally, plant cover was positively correlated to the Shannon and Simpson indexes for both farming systems. According to principal component analysis (PCA), for axis 1, positive correlation was detected among the plant species richness, soil temperature, and Shannon and Simpson diversity indexes, whereas for axis 2, negative correlation was detected between plant cover and soil pH. It can be concluded that the organic management system enhances herbaceous plant cover and diversity (species richness, Shannon and Simpson indexes) in olive grove ecosystems during the winter.