Plant community structure of the floating meadows of a hypereutrophic wetland in the Indo-Burma Biodiversity Hotspot

The population of the globally endangered hog deer (Axis porcinus) has declined severely across its geographic range. Intensive monitoring of its demographic and genetic status is necessary. We examined the demographic and genetic structure of a small hog deer population in Keibul Lamjao National Park (KLNP), located on the western fringe of the Indo-Burma biodiversity hotspot for conservation planning. The distribution pattern of hog deer in the Park was derived based on the presence/absence of faecal pellets in 1 km × 1 km grids. We used double-observer distance sampling method to derive the hog deer abundance and population structure and compared with previous data to derive the population trend. We determined the genetic diversity of the population through microsatellite screening and bottleneck detection. The overall pellet density was 0.34 ± 0.02 pellets km-2 restricted to only 22.34 ± 0.20 km2 area of the park. The estimated density of the deer in the park was 1.82–4.32 individuals km-2. The population showed a declining trend from 2006–08 (p < 0.05, R2 = 0.916) with 8% annum-1 and an increasing trend from 2003–2018 (p < 0.05, R2 = 0.9304) with 10% annum-1. The adult male-to-female ratio and fawn-to-doe ratio were 36.2 ± 1.9 males per 100 females and 16.5 ± 0.4 fawns per 100 females, respectively. The molecular examination suggested that the mean number of alleles at 23 loci was 2.70 ± 0.18, the observed heterozygosity (Ho) ranged from 0.26 to 0.63 (mean 0.42 ± 0.02), the expected heterozygosity (He) ranged from 0.23 to 0.73 (χ = 0.51 ± 0.03), and the polymorphic information content (PIC) ranged from 0.2 to 0.67 (χ = 0.43 ± 0.03) indicating a moderate level of genetic diversity. Although no bottleneck in the population was observed, the loss of genetic diversity may affect the evolutionary potential of the species at the site by limiting the selection flexibility. Conservation planning coupled with scientific management regime will help in the long term persistence of the population in the region.

Factors affecting forage selection by the endangered Eld's deer and hog deer in the floating meadows of Barak-Chindwin Basin of North-east India

In urban areas, human activities result in the discharge of a variety of chemical substances into the environment. This affects soil quality, plant species diversity and human security. To suggest appropriate management strategies that ensure soil quality and human security amid urbanization, this study assessed the relationship between macrophyte diversity and some soil characteristics of wetlands that are adjacent to urban, peri-urban and rural areas in Bamenda Municipality, Cameroon. Plant communities were sampled for species composition and relative abundance, using the Braun-banquet method. Species richness was evaluated using Simpson’s diversity index. Twenty-one soil samples (0–25 cm depth) were randomly collected within the wetlands and analyzed for their physicochemical characteristics using standard methods. The hierarchical cluster analysis (HCA) was used to group the wetlands under managing units. The dominant species ranked in order of abundance in the rural wetland were Raphia farinifera > Ludwigia hexandra > Coix spp. > Leersia hexandra > Ehchinochloa paramidelis. The Peri-urban wetland dominant species stood at Commelina bengalensis > Leersia hexandra > Cyperus distance > Ehchinochloa pyramidalis. In the Urban segment, Pennisetum purpureum > Echinochloa pyramidalis > Tithonia diversifolia > Leersia hexandra were the abundant species. The Simpson index of diversity was 0.94 for the urban and 0.96 for the peri-urban and rural sites respectively. The soils were slightly acidic with pH KCl ranging from 4.87 to 5.41. From the coefficient of variability classes, Sand, pH-H2O, pH-KCl, and Na consistently varied slightly across the three sites. Two significant clusters (management units) representing a combination of urban, and peri-urban/rural were formed from the hierarchical dendrograms. The Mann–Whitney U test revealed a significant (P < 0.05) lower exchange acidity in the rural than the urban sites indicating contamination of the urban site, reducing its macrophyte diversity. Intensification and extension of urbanisation are gradually reducing the macrophyte diversity and also contaminating the soils of the wetlands of the Bamenda municipality in Cameroon, warranting monitoring. The chemical composition of soils in the urban cluster needs early remediation by encouraging the planting and monitoring of certain plants that can already take up the elements.

The relationship between vegetation and surface pollen deposition is examined at Storbreen glacier foreland where a clear plant succession exists. The aim is to determine whether the distinct plant communities present produce characteristic pollen assemblages. The influence of environmental factors is also considered. Pollen assemblages from moss polsters, collected from 22 paired sampling sites across the foreland, are compared with local vegetation. Two-way indicator species analysis and detrended correspondence analysis are employed to identify clusters and sequences, initially in the vegetation data and subsequently in the pollen data sets. Vegetation and pollen data are compared simultaneously using canonical correspondence analysis. Three main plant communities are distinguished: pioneer, heath and snowbed. Broadly, each community produces characteristic pollen assemblages. Boundaries between groups are not clear-cut, reflecting the mosaic of plant communities present. Recognition of distinct plant communities is hampered by the prevalence of long-distance arboreal pollen and poor representation of entomophillously pollinated taxa. Late in the succession up to 78% of pollen could originate locally. Use of the non-arboreal pollen sum significantly improves correspondence with vegetation. The importance of indicator taxa is considered and both Salix and Empetrum are found to distinguish successfully early phases of succession from later phases. Strong correlations exist between the primary ordination axes of vegetation and pollen and with terrain age and altitude (for example, the correlation between altitude and total land pollen Axis 1 is r= -0.76). The surface data add new information to the interpretation of tree colonization in the area during the Holocene.

Quantitative classification and ordination are instrumental in improving our understanding of plant community patterns and facilitating effective conservation efforts in national mountain ecosystems worldwide. However, there has been a lack of relevant research focused on arid and semi-arid mountain ecosystems. This study aims to address this gap by investigating the Ningxia Helan Mountain National Nature Reserve (located in Northwest China). We conducted a comprehensive study on the patterns of plant communities and their association with environmental factors across a broad elevation range from 1200 m a.s.l. to 2600 m a.s.l. Our findings revealed the presence of 121 angiosperm species across 41 families, with vegetation classified into six distinct groups through two-way indicator species analysis (TWINSPAN) along the elevational gradient. Notably, the communities of Ulmus, Prunus, and Stipa in the middle elevation range exhibited the highest Shannon–Wiener (SW) and Simpson (SN) diversity indices, and these indices followed a single-peak pattern with increasing elevation. Canonical correspondence analysis (CCA) further revealed six distinct yet interrelated plant communities, revealing elevation (ELE) and the biological aridity index (BK) as the most influential environmental factors influencing plant communities’ distribution. This understanding is critically important for biodiversity conservation and the management of ecosystems in arid and semi-arid mountain ecosystems.

Endozoochory by exotic mammalian herbivores could modify vegetation composition by facilitating the dispersal and establishment of exotic and native plant species. We examined the potential for endozoochoric dispersal of native and exotic plants by exotic hog deer (Axis porcinus) in south-eastern Australia. We quantified the germinable seed content of hog deer faecal pellets collected in five vegetation types within a 10,500-ha study area that was representative of their Australian range. Twenty exotic and 22 native species germinated from hog deer faecal pellets and significantly more native species germinated compared to exotic species. Seedlings of the encroaching native shrub Acacia longifolia var. sophorae emerged, but no native trees emerged and the percentage of grasses that germinated was low (11%). The species composition of germinants was similar among the five vegetation types. We estimated that the hog deer population in our study area could potentially disperse >130,000 viable seeds daily. Our study shows how an exotic mammal can disperse seeds from both native and invasive plants and highlights the need for endozoochory to be considered more widely in studies assessing the impacts of exotic mammals on plant communities.

summaryFew studies have examined patterns of pollen deposition or the relationship between vegetation and pollen assemblages at the small scale. This paper examines the representation of both individual taxa and whole plant communities in modern pollen spectra. Micro‐scale variations in modern pollen deposition were studied in three alpine plant communities on Storbreen glacier foreland, southern Norway: a pioneer community; a Salix‐shrub community; and an ericaceous heath community. The relationships between vegetation and modern pollen deposition and the variability of these relationships at the local scale were investigated within 16 × 1 m2‐quadrats. The data were classified using two‐way indicator‐species analysis (TWINSPAN) and ordinated using detrended‐correspondence analysis (DCA). In addition, the pollen and vegetation data were ordinated simultaneously, using canonical correspondence analysis (CCA). The effect of removing arboreal pollen from the pollen sum was examined. The three plant communities were distinguished successfully by multivariate statistical techniques, using; both pollen data and vegetation data. However, within the communities there was high variability in pollen deposition, which was most pronounced in the Salix‐shrub community. The abundance of individual taxa in the vegetation was compared with their representation in the pollen spectra. The strongest relationships were shown by Salix Ericales, Empetrum and Lycopodium. Certain taxa showed consistent, reproducible patterns of behaviour. These patterns provided valuable evidence for separating contrasting plant communities. Comparison of modern pollen‐vegetation relationships of this kind with pollen data from Holocene and Pleistocene sites is important to improve the reconstruction of past plant communities. Statistical analyses showed that for the majority of taxa a moss polster consisting of 20 subsamples was necessary to reduce the effect of microscale variability in this environment to acceptable levels.

Elemental characterization of antlers of various deer species using X-Ray Fluorescence (XRF): A tool for forensic examination

Hog deer (Axis porcinus) are among the rarest animals in the world and are listed as "Endangered" on the International Union for Conservation of Nature’s Red List of Threatened Species. Protected areas in Nepal are home to large and stable populations of hog deer relative to other parts of hog deer range, but changes in predator abundance, human activities, and climate change could alter hog deer abundance. Reliable and efficient methods to assess hog deer population trends are therefore essential to monitor changes over time. Combined with data on population numbers, support from local communities towards hog deer conservation is important in identifying key threats and developing appropriate conservation strategies. Accordingly, this research integrated natural and social sciences to evaluate density estimation methods and community support for hog deer conservation within Shuklaphanta National Park (SNP), Nepal. Distance sampling along line transects is a common and relatively simple approach used to monitor hog deer populations in Nepal. Recent advances in technology, however, have enabled alternative approaches using data from remote-sensing cameras. Knowledge of the effectiveness of these two approaches could inform future monitoring efforts. Accordingly, I compared two methods for estimating the density of hog deer: distance sampling along line transects (n=17) and a random encounter model (REM) applied to data from remote-sensing cameras (n = 30). The density estimate produced by distance sampling (33.58 ± 8.48 individuals per km²) was more than double the estimate produced using the REM (12.95 ± 0.04 individuals per km²). Of the two methods, the estimate from the REM was more aligned with previous estimates of hog deer density. In addition, camera surveys facilitated the collection of data on multiple species, behaviour, and habitat use compared with line transects. However, despite requiring almost same amount of time for data collection, camera surveys proved to be more costly. These findings highlight the need for a comparison of these density estimation methods with established techniques such as mark-recapture or block counts, coupled with expanded survey efforts to assess the accuracy of estimates. To assess community support for hog deer conservation, I worked with research assistants to interview residents (n=30) from municipalities in the buffer zone surrounding SNP. Interview participants were knowledgeable about deer as a species group, but half of participants did not distinguish hog deer from other deer species. Most participants expressed positive attitudes towards hog deer conservation, especially in the context of promoting the local tourism economy around wildlife viewing. Participants explained that crop damage from deer has been largely mitigated by current management practices, such as fencing, but that additional fencing would further reduce conflicts. My findings revealed opportunities for collaboration between park managers and communities within the buffer zone, particularly around the development of the wildlife tourism industry and the design of management approaches such as fencing. Combined, my research provides guidance for future research and education efforts targeted at hog deer conservation.

Vegetation and environmental data were collected at 266 sampling points distributed in a regular manner along transects covering the Broggerhalvoya peninsula, on the north-western coast of Spitsbergen. Transects with sampling points were drawn in advance on aerial photographs. The analysis of releves and collection of ground data along transects represent an efficient, representative and precise way of sampling. The vegetation data were classified and 19 plant communities distinguished. The plant communities were subjected to detrended correspondence analysis (DCA). Among the recorded variables, moisture is the one with the highest correlation along axes one and two, and reflects a coincidental moisture and vegetation cover gradient. The vegetation component responsible for this positive correlation is the bryophytes. Likewise, the TWINSPAN classification confirms this gradient in a dendrogram reflecting the hierarchical structure of the plant communities. Plant communities constitute the base of a statistical model that links the communities and the SPOT satellite data. The model then classifies and maps plant communities by means of satellite data, covering the entire Broggerhalvoya peninsula. Satellite data and environmental data were analysed regarding their ability to distinguish the plant communities in a discriminant function analysis (DFA). The results of the DFA indicate that it may be reasonable to include all the information from the different satellite channels when using satellite data for vegetation classification purposes. Among the satellite data the panchromatic channel is the one adding the most unique information to the power of the model in separating plant communities. The classification of satellite data using the probability model indicates that plant communities with less than 30% vegetation cover could be classified with the same degree of confidence or better, as compared with plant communities with more than 30% vegetation cover. The overall percentage of correctly classified releves increased by 13% when using probability level two instead of level one (57.8 to 71.1%). The probability classification model makes it possible to experiment with different probability levels to improve the fit between the vegetation and satellite data classification.

Vegetation and species diversity patterns in conservation areas near big cities are poorly known. These are important recreational areas used also for educational purposes. Therefore, investigations of local diversity patterns are urgently needed. The Baihua Mountain Reserve is close to the city of Beijing and is the northern end of the Taihang mountain range in north China. Sixty-one 10 × 20 m quadrats of plant communities were established along gradients for elevation (750–2043 masl) and disturbance (mainly due to tourism and agriculture). Data on species composition and environmental variables were measured and recorded in each quadrat. Two-way indicator species analysis and canonical correspondence analysis (CCA) were used to analyze the relationships between vegetation and environmental variables, while species diversity indices were used to analyze the pattern of species diversity. Twelve plant communities were found, mostly secondary forests with some plantations. These communities are representative of the vegetation in the mountains west of Beijing. Each community had a different composition, structure, and environment. The variation of plant communities was significantly related to elevation and disturbance and related to litter thickness, slope, and aspect. The cumulative percentage variance of species–environment relationships for the first 4 CCA axes was 89.6%. Elevation and disturbance intensity were revealed as the factors that most influenced community distribution and species diversity. Species richness, heterogeneity, and evenness all showed a “humped” pattern along elevational and disturbance gradients—the highest species diversity appeared in the middle elevation and under medium disturbance intensity. Recommendations regarding management measures are made.

PDF HTML阅读 XML下载 导出引用 引用提醒 洮河国家湿地公园主要植物群落多样性对土壤环境因子的响应 DOI: 10.5846/stxb202101090098 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金（41461013和41861009） Response of main plant community diversity to soil environmental factors in Taohe national wetland park Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:内陆河湿地原生植被群落多样性对土壤环境因子的响应分析，有助于深入理解河岸带原生植物群落的生态适应策略。采用双向指示种分析（two-way indicator species analysis，TWINSPAN）和典范对应分析（canonical correspondence analysis，CCA）方法对研究区27个样方的原生植物群落进行分析，研究河岸带植物群落多样性与土壤因子之间的关系。结果表明：研究区主要原生植物有8种生活型，群落类型可分为女贞（Ligustrum lucidum）+野蔷薇（Rosa multiflora）群落、杠柳（Periploca sepium）群落、艾蒿（Artemisia argyi）+狗娃花（Heteropappus hispidus）群落、旋覆花（Inula japonica）+败酱（Patrinia scabiosaefolia）群落、沙棘（Hippophae rhamnoides）+小檗（Berberis thunbergii）群落和沙棘+红花岩黄耆（Hedysarum multijugum）群落6类。群落的Shannon-Wiener多样性指数（H'）整体呈下降趋势，Pielou均匀度指数（J）呈现增减交替的趋势，Simpson优势度指数（C）整体呈增加趋势，土壤粉粒含量与Simpson优势度指数（C）呈显著正相关关系（P<0.05），其他土壤因子与多样性指数无显著相关关系（P>0.05），表明土壤中粉粒含量是影响河流湿地原生植物群落分布和多样性的关键因子之一。内陆河流湿地土壤质地类型的差异性一定程度上决定河岸带湿地生态系统原生植物群落的种类组成和分布格局。 Abstract:Analysis of the adaptability of the distribution and diversity of virginal vegetation in inland river wetland to soil environmental factors is helpful to understand the ecological adaptation strategies of the native plant communities in riparian zone. This study aims to examine the response of main plant community diversity to soil environmental factors in Taohe national wetland park. The two-way indicator species analysis (TWINSPAN) and the canonical correspondence analysis (CCA) methods were used to analyze the native plant communities of 27 quadrats in the study area. The study site was located in the national wetland park conservation areas in Lintao County, Gansu Province, China (35°05'27″-35°15'58″ N, 103°45'43″-103°50'55″ E). Firstly, in the riparian zone on both sides of the middle section of Taohe National Wetland Park, a flat area with relatively intact native vegetation (vegetation formed by nature but not affected by obvious human activities), less disturbance from human activities, and no obvious topographic fluctuation was selected in the direction of vertical river. Secondly, the 27 representative sample plots, including shrub and herb communities were selected. A 5 m+5 m shrub quadrat was set in each shrub plot. The height, density and coverage of all species in the quadrat were recorded in the survey of shrub community. In the investigation of herb community, 3 plots (1 m+1 m) were randomly selected from the thicket quadrats, and the height, coverage, density, frequency and life type of all plants in each quadrat were recorded in detail. The results showed that there were 8 life types of the main native plants in the study area, and the community types could be divided into 6 types. They were Ligustrum lucidum+Rosa multiflora community, Periploca sepium community, Artemisia argyi+Heteropappus hispidus community, Inula japonica+Patrinia scabiosaefolia community, Hippophae rhamnoides+Berberis thunbergii community, and Hedysarum multijugum community. Besides, Shannon Wiener diversity index (H') showed a decreasing trend as a whole, while Simpson dominance index (C) displayed opposite changing trend, and Pielou evenness index (J) exhibited a trend of increase or decrease in alternate. Moreover, there was a significantly positive correlation (P<0.05) between the content of soil silt and C, and there was no significant correlation between other soil factors and the diversity index (P>0.05), indicated that the soil silt content of the soil was one of the key factors affecting the distribution and diversity of native plant communities in river wetland. The difference of soil texture type in inland river wetland determines the species composition and distribution pattern of native plant communities in riparian wetland ecosystem to some extent. 参考文献 相似文献 引证文献

Aims: This study identified, classified and mapped the different plant communities found on the Telperion Nature Reserve. Study area: Telperion Nature Reserve, Mpumulanga, South Africa. Methods: Using a 1:10,000 aerial photograph, Telperion was delineated into homogenous physiognomic-physiographic units. 294 sample plots (100 m2) were placed in a randomly stratified manner within identified homogenous units. Plant species present in sample plots were recorded and allocated a modified Braun-Blanquet cover abundance scale value. Sample plot data were captured into TURBOVEG and exported for editing, classification and processing in JUICE. A modified TWINSPAN classification was applied to derive a first approximation of the plant communities in a synoptic table that was refined using Braun-Blanquet procedures. Species were manually arranged into groups. Diagnostic, constant and dominant species were statistically determined from the synoptic table. Threshold values for fidelity, frequency and canopy cover were set and a final phytosociological table was produced for describing the plant species composition for the different plant communities. Results: 22 plant communities were identified for Telperion. Five were major communities, 14 were sub-communities and 13 were variants. The five major plant communities were Cyathea dregei–Ilex mitis ravine woodland, Paspalum urvillei–Phragmites australis valley bottom wetland, Diospyros lycioides–Combretum erythrophyllum riparian woodland, Eragrostis curvula–Seriphium plumosum midslope plateau grassland, and Combretum molle–Englerophytum magalismontanum rocky ridge woodland. The plant communities were also described and mapped. Conclusions: The classification, description and mapping of Telperion’s vegetation provides a basis for management decision making about wildlife stocking rates, fire planning, and vegetation management. Findings indicate that Bankenveld vegetation is heterogeneous with a variety of habitats including woodland and grassland components. Telperion has a variety of plant communities and a high plant species diversity, making it a reservoir for plant species and an important conservation area. Taxonomic reference: SA-Plant Checklist-2019–2020, South African National Biodiversity Institute, 2020, Botanical Database of Southern Africa (BODATSA) (http://posa.sanbi.org/) [accessed January 2022]. Abbreviations: BB = Braun-Blanquet; m a.s.l. = metres above sea level; TWINSPAN = Two-way indicator species analysis.

We describe a protocol for the identification of two endangered cervids from decomposed and degraded samples based on the mitochondrial DNA cytochrome b (cyt b) gene and control region (D-loop) analysis. The identification of the species was achieved using DNA extracted from 16 unknown carcasses and two references samples of Eld’s deer (Rucervus eldii) from captivity and contrasted with existing sequences of Eld’s and hog deer (Axis porcinus) from GenBank. Phylogenetic analysis confirmed that of the 16 samples, 14 were of hog deer and two were of Eld’s deer. From the study, we concluded that the method adopted in this study is useful for establishing species-identity from degraded biological samples.

The reliability of packed cell volumes (PCV), total solids (TS), blood glucose (BG), γ-glutamyl transferase (GGT), and glutaraldehyde test in determining passive transfer of colostral immunoglobulins was investigated in nine species of cervids: axis deer (Axis axis), hog deer (Axis porcinus), sika deer (Cervus nippon), tufted deer (Elaphodus cephalophus), Père David's deer (Elaphurus davidianus), pudu (Pudu puda), sambar deer (Rusa unicolor), barasinga deer (Rucervus duvaucelli), and Eld's deer (Rucervus eldii). Individually the parameters evaluated were significant though imperfect predictors of passive transfer status in cervids. Interpreted collectively as a panel along with neonate condition, these tests were clinically helpful in diagnosing failure of passive transfer (FPT). Collectively interpreting test results as a panel along with clinical assessment of the animal is recommended. Some species-specific variations in TS, GGT, and glutaraldehyde test results were identified.