Main Plant Communities Research Articles

Classification of montane grasslands in central Argentina

AbstractQuestionWe address the following questions: (1) which are the main plant communities in montane grasslands in central Argentina; (2) do those communities differ in terms of floristic composition, endemisms, chorotypes and life forms; and (3) which are the major environmental variables (climatic, topographic and edaphic) associated with the heterogeneity of the vegetation?LocationPampean Mountains (Sierras Pampeanas), Córdoba Province, central Argentina, an area of ca. 37,000 km2.MethodsThe survey was based on a data set comprising 746 relevés and 822 vascular plant species, collected in accordance with the Braun‐Blanquet sampling method. The data were classified using the hierarchical ISOmetric feature mapping and Partitioning Around Medoids, and ordinated through isometric feature mapping (ISOPAM). The environmental variables were related to the ISOPAM ordination.ResultsThe ISOPAM classification identified two clusters, five vegetation types and 17 plant communities, which were distributed across different elevations. There were notable differences in the diagnostic species, average percentages of endemic species, chorotypes and life forms among the various vegetation types and plant communities. The primary gradient in grassland vegetation was found to be associated with elevation and related climatic variables.ConclusionsThe study provides valuable insights into the montane grasslands of the Sierras Pampeanas in central Argentina. It presents a comprehensive classification of the region's grasslands, including tall tussock grasslands, humid grasslands, stony grasslands, and grasslands with scattered shrubs and trees. Each recognized unit is distinguished by diagnostic species and a distinct floristic composition. Our findings emphasize a significant division between grasslands at higher elevation, abundant in Andean species, and Piedmont and shrubby grasslands at lower elevations, characterized by a higher prevalence of Chacoan and other Neotropical species. Grassland vegetation in other regions of the Sierras Pampeanas remains poorly studied, requiring additional research to determine the syntaxonomic position of this vegetation.

Pollen signal of modern vegetation registered in surface soil samples along an elevation gradient from Iztaccíhuatl volcano, central Mexico

AbstractCharacterising the vegetation-pollen signal is a crucial task for enhancing the interpretation of fossil pollen records. This study analyses 28 surface soil samples collected in the surroundings of Iztaccíhuatl volcano, between 2,650 and 4,024 m asl. Pollen zones and ordination analysis were assessed to establish a qualitative connection between the pollen signal and the distribution of plant communities along the elevation gradient. The results show: (i) the predominant pollen type in the pollen assemblage is Pinus; (ii) pollen grains of Quercus and Alnus are present along the elevation gradient, even at high elevations where the parental plants are not typically found; (iii) samples taken between 2,650 and 3,338 m asl., where fir forests dominate, exhibit higher values of Abies pollen compared to samples above 3,405 m asl.; (iv) the locally-dispersed pollen of the hemiparasite Arceuthobium results key in identifying the presence of pine forests; and (v) pollen taxa such as Apiaceae, Eryngium, Valerianaceae, and Caryophyllaceae are linked to higher elevations, specifically where the plant communities of Pinus hartwegii and alpine grassland occur. The study suggests that the pollen signal along the elevation gradient is useful to characterise the main plant communities of the study site (fir forest, pine forest and alpine grassland). Additionally, the percentage variations of Abies in the pollen signal below 3,600 m asl. show the reduction of fir forest communities resulting from recent human activities in the area.

Characteristics of main plant communities on uninhabited islands in Bohai Sea, China

Characteristics of main plant communities on uninhabited islands in Bohai Sea, China

Acidophilous grasslands in the Locarnese region (Southern Switzerland): description and classification of main plant communities

This paper presents a phytosociological study of dry and mesophilous meadows and pastures in the Locarnese region (Insubria - Southern Switzerland). Seventy-one vegetation relevés were analysed using both hierarchical classification and nonmetric multidimensional scaling (NMDS) ordination. Seven main clusters were identified and described as follows: (i) xerophytic grasslands on sandy soil dominated by Koeleria macrantha; (ii) mesophilous meadows with Arrhenatherum elatius and Centaurea transalpina; (iii) semi-dry meadows with Chrysopogon gryllus; (iv) semi-dry grasslands with Carex fritschii and Thalictrum minus; (v) nutrient-poor Phyteuma betonicifolium-Festuca nigrescens montane zone grasslands; Nardus stricta grasslands dominated by (vi) Festuca paniculata or (vii) Carex pilulifera. From a phytosociological point of view, a new association named Phyteumo betonicifolii-Festucetum nigrescentis, classified into the Nardo strictae-Agrostion tenuis alliance was proposed. In addition, we confirmed the presence of the Holco-Chrysopogonetum grylli association, within the Bromion erecti, which up to now was provisional only.

Decoupled functional and phylogenetic diversity provide complementary information about community assembly mechanisms: A case study of Greek forests

Understanding the mechanisms of community assembly is of great importance to biogeography and ecology. Simultaneous investigation of the functional and phylogenetic facets of diversity has been proposed as a useful approach that allows inferences about such mechanisms. This study applies such an approach to explore diversity and structure within and among the main plant community types of mountainous forests in northern and central Greece. Functional and phylogenetic diversity and structure were measured in 25 community types of broadleaved deciduous and mountainous coniferous forests. Functional richness and Faith’s phylogenetic diversity were used to assess diversity, while mean pairwise functional and phylogenetic distances were used to investigate structure. Relationships between both facets of diversity and structure, as well as community types, were tested using boosted regression trees separately for all vascular plant taxa and taxa occurring in the forest understorey. Phylogenetic diversity was positively correlated with functional diversity, but phylogenetic structure was not a good predictor of functional structure. The understorey dataset revealed non-random structure for more vegetation plots than the dataset with all taxa. Habitat effects, represented by community types, were found to be better predictors of functional structure than phylogenetic structure, highlighting the need to account for habitat variability in studies of community assembly. In our study system, the two diversity facets provide complementary information on the structure of community types since most of the vegetation plots studied were found statistically significantly structured for one diversity facet (functionally clustered or phylogenetically overdispersed) and random for the other. Our results indicate that functional and phylogenetic measures provide different insights into the mechanisms driving the assembly of the forest community types studied.

环境筛选和扩散限制对长江流域湖北段湿地植物群落构建的共同影响

PDF HTML阅读 XML下载 导出引用 引用提醒 环境筛选和扩散限制对长江流域湖北段湿地植物群落构建的共同影响 DOI: 10.5846/stxb202201110110 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 湖北省教育厅项目（T201701）；湖北省科技厅项目（2020CFA005）；国家自然科学基金项目（31570366） Environmental filtering and dispersal limitation jointly affect wetland plant community assembly in Hubei section of the Yangtze River Basin Author: Affiliation: Fund Project: Project of Department of Education of Hubei Province(T201701); Project of Department of Science and Technology of Hubei Province(2020CFA005);Project of National Natural Science Foundation of China(31570366) 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:湿地植物群落构建机制的研究可为湿地生态系统管理和受损湿地生态恢复与重建提供重要理论依据。地处长江流域的湖北省是我国湿地资源最为丰富的地区之一，通过野外调查研究了长江流域湖北段内不同类型湿地中的主要湿地植物群落类型，分析了研究区内湿地植物群落物种β多样性格局；利用相关性检验（Mantel test）方法和基于相似或相异度矩阵的多元回归模型（MRM）分析了环境差异和地理距离与湿地植物群落的物种相异性的相关性，及其对该区域湿地植物群落构建的相对贡献率。结果表明长江流域湖北段8个不同类型湿地内的湿地植物群落物种相异性指数差异显著，群落间物种相异性指数与地理距离和环境距离均呈显著正相关关系；MRM分析表明环境筛选和扩散限制共同解释了研究区内群落物种变异指数的54.72%；其中，环境距离独立解释率为22.03%，地理距离独立解释率为9.98%，二者联合解释率为22.71%。结果表明环境筛选和扩散限制共同影响了长江流域湖北段湿地植物群落构建过程，且环境筛选贡献更大。建议除了考虑空间尺度、环境因子、植被类型外，未来需进一步研究时间尺度及人类干扰等因子对该区域湿地植物群落构建的影响。 Abstract:Studies on the mechanism of wetland plant community assembly can provide an important theoretical basis for wetland ecosystem management and ecological restoration and reconstruction of the damaged wetlands. There are very abundant wetland resources in Hubei Province located in the Yangtze River Basin. In this study, we investigated main wetland plant communities by conducting the field survey and analyzed the β-diversity of wetland plant community in Hubei section of the Yangtze River Basin. The correlation between species dissimilarity of wetland plant communities and environmental distance and geographic distance, and relative contribution of environmental differences and geographic distance for accounting for community assembly were tested, using the Mantel test method and a multiple regression model based on similarity or dissimilarity matrices. The results showed that the species dissimilarity index of wetland plant communities in eight different types of wetlands in Hubei section of the Yangtze River Basin were significantly differed. The species dissimilarity indexes among wetland communities significantly were positively correlated with geographical distance and environmental differences. MRM analysis showed that environmental filtering and diffusion limitation together explained 54.72% of the community species variability index in the study area. The independent effects of the two tested hypotheses above mentioned were 22.03% and 9.98%, respectively. Our findings implied that the combined effects of environmental filtering and diffusion limitation decided wetland plant community assembly in Hubei section of the Yangtze River Basin, and in comparison to diffusion limitation, the environmental filtering had stronger effects. We argue that other factors, such as time scale and interference, should be considered in a study of wetland plant community assembly, beside spatial scale, environmental factors, and vegetation types. 参考文献 相似文献 引证文献

Topological differentiation of the vegetation cover of the Sandomiria Upper Dnister geobotanical district

The article provides distribution patterns of natural vegetation depending on topological conditions and outlines the main directions of its anthropogenic transformation. The boundaries as well as botanical and geographical features of the studied district are specified. The syntaxonomic classification of plant communities is presented. The combinative ecological and coenotic profile was created showing distribution patterns of the main plant communities in relation to changes in the indicator values of ecological factors. Three types of mesocombinations are distinguished: forest, grassland (meadow) and swamp-flood ones. Averaged (relevant) indicator values were calculated based on environmental conditions. It has been established that the forest range is characterized by the indicators close to the background ones, which indicate a high stabilizing role of forest ecosystems. Correlative dependence between changes in indicators of certain factors was found, that enables to predict possible cause-and-effect changes. Under current trends of anthropogenic and climatic changes, a decrease in the humidity regime along with raise in soil pH can be expected in the future, while increase in seasonal changes in moisture will accelerate processes of nitrification and soil mineralization. Some habitats within the district are under significant negative effect of invasive species, e.g. the territory between the Lomnytsia River and Kolomyia town is classified as the one under the highest degree of threats due to huge, probably largest in Ukraine, areas of Heracleum sosnowskyi, Erigeron annuus, Solidago canadensis and Rudbeckia laciniata. In the future, this region may undergo substantial transformation and a special attention is required to protect its biodiversity.

Effect of climate change on fir forest communities in the mountains of South-central Greece

The endemic oro-Mediterranean fir (Abies spp.) forests in Greece are valuable ecosystems with high ecological and economic importance. In the mountains in south-central Greece, the availability of moisture plays a crucial role in the floristic composition, structure and distribution of fir forest communities. Because of the predicted adverse climate changes for the Mediterranean zone, suitability of many habitats for the growth of fir forests will change. This study aims to quantify the degree to which these forests will be affected by climate change. Current and future climatic conditions in the area studied were estimated for two periods of time (2041 – 60, 2061 – 80) and two climate change scenarios (RCP 4.5, RCP 8.5). Vegetation releves were classified and ordinated. Recursive partitioning was used to reveal the most important factor for discriminating the main plant communities and determining the ecological threshold between them. Current and future suitability of bioclimatic space for fir forest communities was identified. The effect of climate change was assessed based on predicted changes in the potential distribution, in terms of size and location, of fir forest communities. Two plant communities that reflect the differentiation of fir forests into xerophytic and mesophytic forest types are described. Among several climatic variables, spring drought was the best factor discriminating these two forest communities. The quantification of the threshold for drought in these two plant communities was used to predict their potential distribution in the area studied. Potential distribution of fir forests in south-central Greece will change in the future, due to a reduction in suitable bioclimatic space and shift to higher altitudes. The effect is expected to be greater for xerophytic forest communities, especially in the worst-case scenario (RCP 8.5) and in 2061–80.

Weed communities in the irrigated rice paddies of northern Iran

Dedicated insights into the diversity, spatial and temporal distribution of rice weed communities, as well as underlying ecological factors, are critical for developing effective ecological weed management strategies in these agroecosystems, leading to the preservation of biodiversity and ecosystem services in a sustainable agriculture framework. To fulfill this aim, 108 vegetation relevés were conducted at 23 sites of rice paddies throughout 9 counties in the north of Iran at various altitudes, during three different phenological stages of rice. Data from vegetation relevés was analyzed using TWINSPAN, resulting in the identification of four main plant community types related to the different stages of rice growth: Echinochloa crus-galli–Paspalum distichum, Spirodela polyrrhiza–Lemna minor, Monochoria vaginalis s.l.–Marsilea quadrifolia, and Cyperus difformis–Ammannia baccifera. Complementary direct (canonical correspondence analysis) and indirect gradient analyses (detrended correspondence analysis) confirmed these communities’ separation and indicated that the most significant environmental factors affecting plant community distribution were soil water content and soil pH. Moreover, out of 72 segetal species of investigated rice paddies, 12 species were alien to Iran, indicating that this agroecosystem provides an important source for the introduction, distribution, and possible spread of alien species into other adjacent ecosystems. Our findings contribute to the knowledge of detecting patterns of weed composition and distribution in rice paddy ecosystems, as well as their interpretation in relation to environmental gradients. They can support the establishment of ecological weed management practices in northern Iran's paddy fields.

Assessing environmental and plant community changes by phytolith characteristics in sediments from Nanjishan Nature Reserve, Lake Poyang

To assess the impacts of increasing human disturbance, wetland degradation, and biodiversity loss, and to determine the main environmental factors affecting the spatial distribution of phytoliths in Nanjishan Nature Reserve, phytoliths from 17 topsoil samples and a sediment core sample were analyzed. Yellow-brown, silty, and gray-black clays were the main sedimentary constituents, and the total organic carbon content decreased with increasing depth. Lakes Zhanbei, Chang, and Sanniwan were located in an alluvial delta and characterized by intensive human activity and grass communities of Triarrhena lutarioriparia and Zizania latifolia, whereas Lakes Shangbeijia, Beishen, Nanshen and Baisha were characterized by a lower degree of disturbance and grass communities of T. lutarioriparia and Phragmites australis. A total of 11,942 phytoliths (4248 in topsoil and 7694 in core sediment) were isolated from 46 samples and 19 distinct morphological types were identified. Vesicular cells constituted 42%–51% of all samples, short cells 24%–32%, and elongate types 15%–26%. The phytolith assemblages at Lakes Zhanbei, Chang, and Sanniwan were mainly composed of fans, rectangles, points and elongates. While Lake Shangbeijia, Beishen, Nanshen and Baisha were dominated by fans, saddles and elongates. Based on phytolith analysis, we found that the typical communities in the study area were significantly degraded from 1986 to 2003. Sediment cores dated by 210Pb showed that the main plant communities were transformed from Carex and T. lutarioriparia to Z. latifolia, T. lutarioriparia and P. australis.

Ellenberg ecological indicator values, tolerance values, species niche models for soil nutrient availability, salinity, and pH in coastal dune vegetation along a landward gradient (Euxine, Turkey)

Coastal dunes are characterised by plant species adapted to harsh conditions. Salinity and other factors (soil pH, nutrients, and climate events) vary along the landward gradient. The current study investigated the effects of environmental factors on the occurrence and composition of coastal dune plants. Ellenberg ecological indicator values (EIVs), species tolerance values (TVs), and species niche models for salinity, nutrient availability, and soil reaction were determined. EIVs were estimated using weighted averages based on the species cover-abundance for each plot. Species TVs were calculated considering the cover-abundance and EIVs (pH, nutrient, and salinity). Species niche models were determined with the general linear model (GLM). GLM was computed using mean community EIVs, canopy height, and climatic variables. We found that salinity (S) and pH (R) EIVs decreased along the seaside-inland gradient while nitrogen (N) EIVs increased. TVs for S increased landward while S and R TVs decreased. According to GLM, niche models of 28 species for salinity, 25 species for pH, and 21 species for nutrient were significant. In summary, salinity and pH are the main drivers shaping coastal dune zonation and plant community.

三峡水库秭归段消落带植物群落特征及其与环境因子的关系

消落带植被群落特征及物种多样性的研究一直是植物生态学和恢复生态学研究的热点。三峡水库的运行对消落带生态系统造成了极大的影响, 如引起绝大部分河岸带土著植物消失、生物多样性降低以及土壤侵蚀严重等一系列生态学问题。研究消落带植物群落特征及其影响机制, 旨在丰富消落带新生湿地生态学研究内容, 为消落带植被的恢复、湿地保护和管理提供科学依据。通过对三峡水库秭归段香溪河与童庄河陡坡消落带植物群落及其环境因子的实地调查, 并结合双向聚类分析及典范对应分析(CCA), 研究了三峡水库消落带植物群落特征、物种多样性及其与环境因子之间的关系。结果表明：(1)在三峡水库秭归段消落带共发现维管植物34种, 隶属于15科32属, 其中菊科(Compositae)和禾本科(Gramineae)种类数较多, 为优势物种, 植物群落组成以草本植物为主, 一年生和多年生草本植物为23种和11种, 分别占67.65% 和32.35%, 一年生植物占绝对优势；(2)随海拔升高, 物种数、Shannon多样性指数、Pielou均匀度从低海拔到高海拔随着海拔的增加而升高, 而Simpson优势度指数指数从低海拔到高海拔呈下降趋势；(3)双向聚类显示消落带主要包括3种植物群落：狗牙根群落、狗尾草+马唐群落以及鬼针草群落, 中低海拔以狗牙根单优群落为主, 高海拔为狗尾草、马唐、鬼针草及苍耳等为主的共优群落。CCA结果表明海拔与水淹时间是影响消落带植被群落物种组成的主要因子, TN与TK是影响群落物种分布格局的次要因子, 同时消落带土壤贫瘠, 受N、K的限制。库区植物群落物种多样性仍在下降, 需对植物群落和环境因子进行长期的监测与研究。;River systems around the globe are increasingly affected by damming to satisfy increasing demands for hydroelectricity, flood mitigation and reliable water supplies. The impoundment of the reservoirs can significantly alter river flow, shorelines, sediment and aquatic fauna and flora and can result in the loss of original riparian vegetation. After the first impoundment of the Three Gorges Reservoir (TGR) in June 2003 and the complete impoundment in 2010, the water level of the reservoir fluctuates from 145 m a.s.l in summer (May to September) to 175 m in winter (October to April), resulting in formation of the water level fluctuation zone (WLFZ) with a total area of 350 km² in the Reservoir. Compared with other reservoirs, the hydrological regime of the TGR is the exactly opposite of the natural flood rhythms of the Yangtze River with prolonged inundation duration (nearly half a year) and deep submergence depth (up to 30 m). The operation of the Three Gorges Reservoir had significant effects on the ecosystem of the riparian zone, causing a series of ecological problems such as the disappearance of original vegetation and reduced biodiversity in most of the riparian zone, as well as severe soil erosion. These changes might alter plant community characteristics in the WLFZ of the TGR. The study of plant community structure and species diversity in the WLFZ has been a research hotpot in plant ecology and restoration ecology. The purpose of studying the characteristics of plant communities and their influencing mechanisms in the WLFZ is to enrich the ecological research content of newborn wetlands, and to provide a scientific basis for the vegetation restoration, wetland protection and management in the WLFZ. The height, coverage and frequency of each plant species and the soil properties were measured at each elevation zone (145-155 m, 155-165 m, and 165-175 m) in the WFLZ of the Zigui region of the Three Gorges Reservoir (ZRTGR) in 2018. The two-way clustering analysis and canonical correspondence analysis (CCA) were used to analyze the spatial variations of the plant community characteristics and determine the key environmental factors influencing vegetation. The main results were as follows: (1) a total of 34 species of vascular plants, belonging to 15 families and 32 genera, were recorded in the WLFZ of the ZRTGR, with abundant species of Compositae and Gramineae. Vegetation was dominated by herbaceous plants amog which the annual herbs (i.e. Setaria viridis, Digitaria sanguinalis, Echinochloa crusgalli, Bidens pilosa, and Xanthium strumarium) and perennial herbs (i.e. Cynodon dactylon and Cyperus rotundus) accounted for 67.65% (23) and 32.35% (11) of the total number of species, respectively. (2) Species diversity showed an increasing trend with elevation and had significant differences between low, middle and high elevation area (P < 0.05). The species number, Shannon-Wiener diversity index, and Pielou evenness index of the plant community increased with the increasing elevation from the low to high elevation area, whilamonge the Simpson dominance index decreased with the increasing elevation. (3) Using two-way clustering analysis methods, the vegetation in the WLFZ consisted of three main plant community types: Ass. C. dactylon, Ass. S. viridis+D. sanguinalis and Ass. B. pilosa. The low and middle altitudes are dominated by monodominant community of C. dactylon, while the high altitudes are dominated by co-optimal communities of Setaria viridis, D. sanguinalis, B. pilosa and X. sibiricum. The CCA showed that elevation and flooding duration were the most important factors influencing the species composition of the plant community in the WLFZ, while TN and TK were the secondary important factors influencing the species distribution pattern of the community. The soil in the WLFZ was poor and limited by N and K nutrients. The diversity of plant communities in the reservoir area is still declining, which requires long-term monitoring and research of plant communities and environmental factors.

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

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

The resistance and short‐term resilience of a restored extracted peatland ecosystems post‐fire: an opportunistic study after a wildfire

Bogs are known to be relatively resistant and resilient to fire, due to the dominance of wet Sphagnum mosses. Indeed, Sphagnum mosses by holding water, ensure bog resistance, and by regenerating from any fragments left post‐fire, ensure bog resilience. The return of several ecological attributes has been reported in the literature post‐restoration. However, the resistance and resilience have not yet been evaluated in restored peatlands. A fire affecting an extracted peatland restored 10 years ago provided the opportunity to (1) evaluate the losses post‐fire, in terms of phytobiomass and plant cover and (2) assess early vegetation recovery after one growing season post‐fire. The fire response of the restored peatland, in terms of resistance and short‐term resilience, differed between the main plant communities. Sphagnum Lawn communities (Sphagnum species from the Acutifolia subgenus and Eriophorum vaginatum) showed greater resistance to fire losing proportionally less phytobiomass (17%) than Wet Hollow communities (44%) (Sphagnum species from the Cuspidata subgenus and Scirpus cyperinus). Greater resistance of the Sphagnum Lawn likely comes from the Acutifolia Sphagnum species growing in dense carpets with good water retention, along with the E. vaginatum tussocks being able to retain humidity below the tussocks, whereas the looser growth habit of Cuspidata Sphagnum species do not have good capillary rise capacity and Scirpus produced litter that can produce a good fuel. This study reinforces the idea that a peatland restoration approach using reintroduction material dominated by Acutifolia Sphagnum species and tussock cottongrass provides a better resistance and short‐term resilience of restored peatlands.

The distribution pattern and ecological restoration technology of aquatic plants in a eutrophic water landscape belt

Abstract Taking the eutrophic Taige canal and Caoqiao River in the upper reaches of North Taihu Lake as the experimental objects, 12 monitoring points were set up and data were recorded. The distribution pattern of aquatic plants in the water landscape belt was studied by variance/mean ratio, aggregation intensity index, negative binomial parameter, Cassie index and α–diversity index. Based on the principle of aquatic plants repairing eutrophic water, a suitable water environment was selected. The effect of ecological restoration was studied by photometry. The results showed that: the main aquatic plant communities in this area evolved from submerged to floating leaf and emergent plants, which shows that the vertical distribution pattern of the aquatic plant communities was greatly affected by hydrology; the distribution pattern of aquatic plant diversity showed a good single curve in the vertical direction and a single curve in the horizontal direction; the results of ecological restoration showed that the average removal rates of total nitrogen (TN) and total phosphorus (TP) by mixing the three plants were 86.76% and 93.89%, respectively. Among them, the best combination for TN removal was water hyacinth (Eichhornia crassipes) + lytchus (Lythrum salicaria) + calamus (Acorus calamus), and the best combination for TP removal was water hyacinth + lytchus + hibiscus (Nelumbonucifera).

An approach to the use of plants for monitoring soil conditions in wetlands in arid areas

The soil environment is a key factor affecting the distribution of plant communities. The soil environments of many arid wetland areas are deteriorating. The present study investigated plant-soil relationships in an arid wetland region (along the middle reaches of Heihe River, Northwest China). The main objective was to establish an approach to use plants as bioindicators of soil conditions. With such an approach, environmental changes inferred from plant observations can be monitored, facilitating the prevention of negative environmental impacts and the improvement of environmental management. Collection of vegetation data and soil sampling was conducted at a total of 87 plots from 27 stations in the study area from July to August 2017. The vegetation data included plant community type and the abundance, height, and coverage of each species. The soil characteristics included salinity (SA), pH, water content (WC), bulk density (BD), soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP) and available potassium (AK). A total of 13 main plant community types were identified by detrended correspondence analysis. The soil physicochemical properties varied among the different plant communities. Multivariate analysis showed that the vegetation variables were closely related to SA, pH and WC. The quantitative plant-soil relationships was also established to aid the management of the wetlands. Based on the established relationships, an expansion of Calamagrostis spp. would suggest a decrease in soil SA, a replacement of Inula japonica with Equisetum ramosissimum would indicate an increase in soil pH, and an expansion of Tamarix spp. would suggest increases in soil SA and pH. Our results support the use of plants as soil bioindicators of disturbance and the approach of quantitative plant-soil relationship to improve the environmental management of wetland ecosystems in arid areas.

Main plant communities and characteristics of Desert Grassland Nature Reserve in Qitai, Xinjiang, China

Main plant communities and characteristics of Desert Grassland Nature Reserve in Qitai, Xinjiang, China

VARIETY OF FLORA´S ECOTOPS AND SPECIES COMPOSITION IN THE TERRITORIES OF BASALT OPERATING AND ABANDOED QUARRIES IN VOLYN POLISYA

The article deals with the results of researching the diversity of biotypes andtheir floristic composition in the territory of existing and abandoned quarries in Volyn Polissya (Kostopil and Volodymyrets regions, Rivne oblast). Studies have revealed 562 species of higher vascular plants of 347 genera and 92 families. A great variety flora´s species is connected with the diversity of ecotopes that have formed there as a result of anthropogenic and natural factors. Characteristic features of this territory are various micro and mesorelief forms, which differ ecological conditions and determine the ecotopological differentiation of the species composition quarry´s flora and the territory in general. Soil substrate or chemical composition of water have the greatest influence on the plant´s composition of different ecotypes, the sunlight has less influence. The largest species diversity of flora characterized by ecotopes in meadow and tree-shrub vegetation, they are transformed variants of natural groups, as well as overburden dumps and landfills, where the main plant community are synanthropic species, in particular adventitious plats. In some areas, where basalt mining has been stopped for more than 15–20 years there are processes of renaturalization, we can see there spreading of rare plant species.

Flora i zbiorowiska roślinne użytku ekologicznego „Dolina Potoku Olszanickiego – Łąki Olszanickie” w Krakowie

The paper lists 135 taxa and 12 main plant communities found in the Dolina Potoku Olszanickiego – Łąki Olszanickie ecological use area during field research done in 2018–2019. For each taxon, information about the occupied habitat, synanthropic status, number of localities and frequency of occurrence are given. Phytosociological groups of species were distinguished and analysed. In the ecological use area, Conium maculatum, an endangered species (VU) of the Małopolska Upland, was recorded. The occurrence of rush meadow Scirpetum sylvatici (typical and degradated patches), meadow thistle Cirsietum rivularis (various degradative forms) and rush vegetation Caricetum rostratae was found. The main threats to ecological use is degradation of communities and natural succession as a result of cessation of extensive use of meadows (mowing, grazing) and the expansion of the invasive species Solidago gigantea and S. canadensis, which occupy a significant part of the non-forest habitats. Information about needed protection measures is also given. The paper highlights the need for biodiversity protection in urban areas, for their sustainable development and the quality of life of their inhabitants.

Pellet Accumulation as a Proxy for Herbivore Pressure in a Mediterranean Ecosystem

Human activities have dramatically altered the distribution and density of large herbivores worldwide, particularly on islands. For example, thousands of goats were abandoned to the mountains on Majorca Island, Spain, during the tourism boom in the 1960s. Though this mammal is common throughout the Majorcan mountain range, the impact of goats on the main mountain plant communities has not yet been evaluated. To fill this gap, we recorded goat fecal pellet accumulation and assessed the degree of browsing of 9 363 shrubs and trees located within 231 25-m2 strips systematically distributed in two mountain regions of Majorca. We also recorded the degree of regeneration of woody plants inside the same strips. The environmental factors that significantly influenced pellet accumulation were altitude, rock cover, distance to roads and paths, distance to water, and slope. The correlations between the pellet index and degree of browsing depended on species palatability and abundance. Finally, the natural regeneration of plants was heterogeneously distributed and negatively correlated with pellet accumulation. This study indicates that high levels of browsing of unpalatable species in less preferred areas are a clear indicator of strong herbivore pressure, whereas the presence of nonbrowsed palatable species could indicate low herbivore presence. Moreover, this work demonstrates that the relative abundance of fecal pellets is a good indicator of the pressure exerted by feral goats on vegetation at a fine scale. The simple pellet index used in this work correlates strongly with vegetation damage; thus, it could represent a valuable innovative tool to inform sustainable management of feral goat populations in not only Majorca but probably also other Mediterranean islands.