Community Similarity Research Articles

Environmental stress-discriminatory taxa are associated with high C and N cycling functional potentials in dryland grasslands

Increasing environmental stress strongly affects soil microbial communities, but the responses of the microbial assembly and the functional potential of the dominant microbial community in the presence of environmental stress in drylands are still poorly understood. Here, we undertook a broad appraisal of the abundance, diversity, similarity, community assembly, network properties and functions of soil microbiomes in 82 dryland grasslands along environmental gradients. We found that the bacterial and fungal diversity and community similarity showed different sensitivities to environmental stress (decreased mean annual precipitation (MAP) and soil nutrient levels and increased soil pH), and MAP was the most important factor influencing microbial community patterns. In addition, the dominant subcommunity of both bacteria and fungi was more sensitive to environmental stress than the nondominant subcommunity. Although increasing environmental stress decreased microbial phylogenetic clustering, it had no effects on the stochastic and deterministic assembly process balance. Moreover, we identified 101 bacterial and 34 fungal environmental stress-discriminatory taxa that were sensitive to environmental stress, and these bacterial markers showed a high correlation with the abundance of carbon (C) and nitrogen (N) cycling-related genes, whereas the taxa classified as connectors in the network were mainly correlated with C degradation genes. Our study shows that the different responses of bacteria and fungi to environmental stress bring challenges to predicting microbial function, but a relatively small number of taxa play an important role in driving C and N cycling-related functional genes, indicating that identifying an organism's phenotypic characteristics or traits of key taxa may improve our knowledge of the microbial response to ongoing global changes.

Comparing the effectiveness of camera trapping, driven transects and ad hoc records for surveying nocturnal mammals against a known species assemblage

Management and conservation rely on surveys to determine which species are present but some species, such as nocturnal mammals, can be very difficult to detect. Camera trapping, driven transects, and ad hoc records are well-established nocturnal survey methods, but their detection effectiveness has not been tested against known species presence. We tested the effectiveness of these methods with a known assemblage of nocturnal African mammals. We compared camera traps placed at targeted and random locations, driven transects, and informal ad hoc records against one another and the 20 predominately nocturnal medium- and large-sized mammals known to be on site. Species-specific detection patterns, detection curves for each method, and detection effort required per species, were compared to determine the effectiveness of each method. Each of the methods detected at least 60% of known nocturnal mammal species over a 20-month period: driven transects and ad hoc records were the most successful (16/20 80%), followed by targeted camera traps (15/20 75%) and random camera traps (12/20 60%). Jaccard’s Coefficients of Community Similarity peaked at 0.78, showing notable differences in the communities sampled with different methods. There was considerable variation in effort required to detect each species for each method, and the number of species detected with specific levels of effort was also highly variable between methods. We suggest that mixing methods, using different camera placement including use of random locations, and incorporating cost-neutral ad hoc records into formal survey efforts can all greatly increase the overall effectiveness and efficiency of species detection.

Butterfly Community Diversity in the Qinling Mountains

The Qinling Mountains are one of the oldest mountain ranges in China and a global biodiversity research and conservation hotspot. However, there is a lack of systematic research and survey of butterfly diversity in this region. Based on the butterfly taxa, combined with the changes in natural climate, altitude gradient and season in the Qinling Mountains, the butterfly diversity and community structure changes in 12 counties in the middle Qinling Mountains were analyzed by transect surveys and platform data analyses. A total of 9626 butterflies were observed, belonging to 427 species across 175 genera and 5 families. The species richness on the southern slope of the Qinling Mountains was higher than on the northern slope. We also studied the variation in alpha and beta diversity of butterflies. The results show that butterfly species were abundant and the highest diversity was found at the middle altitudes (1000–2000 m). Moreover, there were obvious seasonal differences in both species and number of butterflies. The community similarity in spring, summer and autumn was low, with limited species co-existing. The butterflies in the Qinling Mountains reserve area were the most abundant, exhibiting no significant difference with those in the ecotone and the farm area. Finally, we did an assessment of butterflies as endangered and protected species. In conclusion, our long-term butterfly survey data show that human disturbance and climate and environmental changes jointly shape the butterfly diversity in the middle of the Qinling Mountains.

滇西北退化高寒草甸植物群落结构对刈割的响应

PDF HTML阅读 XML下载 导出引用 引用提醒 滇西北退化高寒草甸植物群落结构对刈割的响应 DOI: 10.5846/stxb202108112210 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 第二次青藏高原综合科学考察研究项目（2019QZKK0307）；国家自然科学基金项目资助（31901394，31860620） Responses of plant community structure to mowing in the degraded alpine meadows, Northwestern Yunnan Province 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:为探究滇西北不同退化级别高寒草甸植物群落结构对外界干扰的响应敏感性，以香格里拉市的典型高寒草甸为研究对象，于2018-2020年在三个退化梯度上（严重退化，S1；中度退化，S2；轻度退化，S3）开展控制刈割实验，进而分析草甸植物物种丰富度、群落组成相似性、群落复杂度和关键种的变化规律。结果表明：（1）刈割后，S1的物种丰富度显著增加（P<0.05），S2和S3的物种丰富度未发生显著变化（P>0.05）；（2）相较于S2和S3，S1梯度的植物群落组成变化最大；（3） S1、S2和S3的植物群落复杂度在刈割后均呈先下降后增加的趋势，但S1的植物群落复杂度变化幅度高于S2和S3；（4）刈割导致各退化草甸植物群落的关键种发生了变化，2018、2019和2020年S1梯度的关键种在豆科（Leguminsae）和蔷薇科（Rosaceae）之间变化，S2梯度的关键种在禾本科（Gramineae）和菊科（Compositae）之间变化，S3梯度的关键种在蔷薇科（Rosaceae）、菊科（Compositae）和禾本科（Gramineae）之间转变。研究表明，滇西北高寒草甸植物物种丰富度、群落组成和群落复杂度对外界干扰响应的敏感性可能随退化加剧而上升，但群落关键种的响应过程较复杂。 Abstract:To explore the sensibility of the response of plant community structure to external disturbances under different degradation conditions in the Northwestern Yunnan Province (NWYP), we conducted a mowing experiment at three degradation gradients (i.e., S1:severe degradation; S2:moderate degradation; S3:slight degradation) in an alpine meadow in Shangri-La from 2018 to 2020. The effects of mowing on community structure indicators, including species richness, community similarity, community complexity and keystone species were analyzed. The results showed that (1) after mowing, the species richness of S1 increased significantly (P<0.05), while the species richness of S2 and S3 did not change significantly (P>0.05). (2) Mowing caused a greater change in community similarity in S1 than in S2 and S3. (3) The network connectivity of plant community decreased firstly and then increased after mowing in all degradation levels. Moreover, the change range of community complexity in S1 was higher than in S2 and S3. (4) The keystone species of plant communities changed in 2018, 2019 and 2020. In S1, the keystone species varied between Leguminsae and Rosaceae. In S2, the keystone species varied between Gramineae and Compositae. In S3, the keystone species varied among Rosaceae, Compositae and Gramineae. The study suggests that the sensitivity of the response of species richness, community composition and complexity of plant community to external disturbance might increase with meadow degradation levels, while the shifting of the keystone species would be complex in NWYP. 参考文献 相似文献 引证文献

Comparative study of species composition, diversity of mosquitoes [Diptera: Culicoidea (Meigen, 1818)] in the Eastern and Western regions of India

Mosquitoes are important insects throughout the world because they are vectors of various diseases in the human population. Out of the 3700 mosquito species known to exist worldwide, 393 are found in India. After Brazil, Indonesia, Malaysia, and Thailand, India is the fifth most mosquito-diverse country. Mosquito diversity was discovered to be highly dependent on environmental factors such as temperature, relative humidity, and altitude, resulting in varying species composition and diversity across the Indian subcontinent. The diversity and species composition of mosquitoes in India's eastern and western regions were compared, and there was a significant difference in diversity. A total of 22 mosquito species belonging to Aedes, Culex, Anopheles, Culiseta, Toxorhynchites, and Armigeres were observed in the eastern region of India. In the western region of India, a total of 26 mosquito species belonging to the Aedes, Culex, and Anopheles families were observed. The calculated value of Sorenson's Coefficient was 0.1666, indicating that community similarity did not show much overlap and that Anopheles was the dominant genus in the studied region. The Bray-Curtis dissimilarity index was estimated at 0.7143 showed much dissimilarity between investigated two regions which showed much dissimilarity in the species composition of mosquitoes between the studied areas. This work is significant for the study of the adverse effect of mosquitoes on the human population.

西藏年楚河流域湿地土壤纤毛虫群落特征

PDF HTML阅读 XML下载 导出引用 引用提醒 西藏年楚河流域湿地土壤纤毛虫群落特征 DOI: 10.5846/stxb202203290781 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: “一江四河”流域生物多样性调研与维持机制评价综合科学考察项目（藏财科教指【2021】1号和藏财教指【2019】01号）；西藏大学研究生"高水平人才培养计划"项目资助（2020-GSP-S042） Characteristics of soil ciliate community in wetland of the Nianchu River Basin, Tibet, China 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:为了研究西藏年楚河流域湿地土壤纤毛虫群落特征及其影响因素，于2020年5月、8月和10月春夏秋三个季节，根据年楚河流域湿地分布特征选取了5个湿地样地共计75个土壤样品，采用"非淹没培养皿法"和"活体观察法"对土壤纤毛虫进行了培养和鉴定，共鉴定出土壤纤毛虫154种，隶属于9纲、19目、43科、70属。结果表明土壤纤毛虫优势类群为前管目（Prorodontida），占11.69%；刺钩目（Haptorida）为次优势类群，占11.04%；罕见类群为游仆虫目（Euplotidae）、瓶纤目（Armophorida）、肾形目（Colpodida）、嗜污目（Philaslasterida）、齿管目（Chlamydodontida）和吸管目（Succorida），共占16.23%。湿地土壤纤毛虫多样性指数在三个季节间均无显著性差异（P>0.05），SD4样地的多样性指数在5个样地中最高；湿地土壤纤毛虫C/P（0.35）<1，表明其土壤环境未污染；土壤纤毛虫群落相似性位于极不相似到中等不相似之间，说明不同样地的物种组成差异性较大；土壤含水量（SWC）、土壤温度（ST）和速效钾（RAK）是影响土壤纤毛虫群落分布的因素。 Abstract:In order to study the characteristics of soil ciliate community and influencing factors in wetland of the Nianchu River Basin, Tibet, China. In May, August and October of 2020, i.e spring summer and autumn three seasons, 75 soil samples from five plots were selected based on the distribution of wetland in the Nianchu River Basin, A total of 154 species of soil ciliates, belonging to 70 genera, 43 families,19 orders and 9 classes, were identified by "non-flooded petri dish method" and "in vivo observation method". The results showed that Prorodontida (11.69%) was the dominant group, Haptorida (11.04%) was the subdominant group, and rare taxa were Euplotidae, Armophorida, Colpodida, Philaslasterida, Chlamydodontida and Succorida, accounting for 16.23% of the total. There was no significant difference in soil ciliate diversity index between the three seasons (P>0.05) in wetland, and the diversity index of the SD4 was the highest among the five plots. The soil ciliates(C/P(0.35)<1), indicating that the soil environment in wetland was not polluted. The similarity of soil ciliate communities ranged from extremely dissimilar to moderately dissimilar, showed that species had great differences in different sites. Soil water content (SWC), soil temperature (ST) and available potassium (RAK) were the main factors affecting soil ciliate community distribution. 参考文献 相似文献 引证文献

Alterations and Prediction of Functional Profiles of Gut Microbiota After Fecal Microbiota Transplantation for Iranian Recurrent Clostridioides difficile Infection with Underlying Inflammatory Bowel Disease: A Pilot Study.

Background and PurposeFecal microbiota transplantation (FMT) has emerged for the therapeutic treatment of recurrent Clostridioides difficile infection (rCDI) with concurrent inflammatory bowel disease (IBD). As the first Iranian population cohort, we examined how gut microbiota and their functional profiles change in Iranian rCDI patients with underlying IBD before and after FMT.Patients and MethodsFMT was performed to eight IBD patients via colonoscopy. Profiles of gut microbiota from donors and recipients were investigated using 16S rRNA gene sequence analysis.ResultsPatients experienced no IBD flare-ups or other adverse effects, and all recovered to full health. Moreover, all rCDI patients lacked the Bacteroidetes present in donor samples. After FMT, the proportion of Bacteroidetes increased until a normal range was achieved. More specifically, the relative abundance of Prevotella was found to increase significantly following FMT. Prevotella was also found to correlate negatively with inflammation metrics, suggesting that Prevotella may be a key factor for resolving CDI and IBD. Gut microbiota diversity was found to increase following FMT, while dysbiosis decreased. However, the similarity of microbial communities of host and recipients did not increase, and wide variation in the extent of donor stool engraftment indicated that the gut bacterial communities of recipients do not shift towards those of donors.ConclusionFMT leads to significant alterations of the community structure of gut bacteria in rCDI patients with IBD. The change in relative abundance of Proteobacteria and bacterial diversity indicated that FMT promotes recovery from intestinal permeability and inflammation in rCDI patients. Moreover, strong negative correlation between Prevotella and inflammation index, and decreased dysbiosis index advocate that the improvement of CDI is possibly due to gut microbiome alteration. Collectively, our findings show that FMT would be a promising therapy to help reprogram the gut microbiome of Iranian rCDI patients with IBD.

Increased Similarity of Aquatic Bacterial Communities of Different Origin after Antibiotic Disturbance

Increased Similarity of Aquatic Bacterial Communities of Different Origin after Antibiotic Disturbance

青弋江流域大型底栖动物群落结构及水质评价

PDF HTML阅读 XML下载 导出引用 引用提醒 青弋江流域大型底栖动物群落结构及水质评价 DOI: 10.5846/stxb202101240247 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金青年项目（41301029）；安徽高校协同创新项目（GXXT-2020-075） Macroinvertebrate community structure and water quality assessment in the Qingyi River Watershed Author: Affiliation: Fund Project: The National Science Fundation of China(General Program, Key Program,Major Research Plan) 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:研究河流大型底栖动物群落结构特征及水环境质量对水生态的保护与修复具有重要意义。以青弋江流域为研究对象，于2020年9月进行了大型底栖动物及水体理化因子的调查，采用相对重要性指数、生物多样性指数及Jaccard相似性系数分析了大型底栖动物群落结构特征，运用丰度/生物量比较曲线法及冗余分析法探究了底栖动物群落受到的干扰程度及其主要影响环境因子，最后利用水生态环境质量综合指数对河流水质进行评价。研究结果表明：（1）共采集鉴定大型底栖动物61种，隶属于3门6纲17目，平均丰度为265.9个/m2，平均生物量41.6 g/m2。相对重要性指数分析显示，日本沼虾（Macrobrachium nipponensis）、中国圆田螺（Cipangopaludina chinensis）、羽摇蚊（Chironomus plumosus）及扁蜉（Ecdyrus）为群落中的主要优势种。（2）由群落相似性分析知，Jaccard相似性系数较低，调查点位之间存在较强的空间异质性。（3）冗余分析表明，电导率、氨氮浓度及流速是影响底栖动物群落结构的主要环境因子。（4）生物指数分析结果显示该流域水质为轻度污染或中度污染，与水质理化因子评价存在较大差异。综合考虑生物及非生物因子的水生态环境质量综合指数模型计算结果显示，流域整体水环境质量偏好，但部分采样点已受到干扰或处于污染状态，与ABC曲线分析及优势种分析基本一致，评价结果更具科学性及可靠性。 Abstract:It is of great significance to study the community structure of macrobenthos and the water quality for protection and restoration of aquatic ecology. Taking the Qingyi River Basin as the research object, a survey of macrobenthos and physicochemical factors of the water body was carried out in September 2020. It analysed the structural characteristics of the macrobenthic community by means of the relative importance index, the biodiversity index and the Jaccard similarity coefficient. It investigated the extent of disturbance to the benthic community and the main environmental factors that affect it, by applying the comparative abundance/biomass curve method and redundancy analysis. Finally, the comprehensive index of water ecological environment quality was used to evaluate the river water quality. The results showed that (1) 61 species of macrobenthos were collected and identified in the Basin, which belonged to 3 phyla, 6 classes and 17 orders. The average density was 265.9 ind/m2 while the average biomass was 41.6 g/m2. The main dominant species which were shown in the index of relative importance in the community were Macrobrachium nipponensis, Cipangopaludina chinensis, Chironomus plumosus, and Ecdyrus. (2) The Jaccard similarity coefficient was low due to the analysis of community similarity, with a strong spatial heterogeneity between the investigation sites. (3) The main environmental factors-conductivity, ammonia nitrogen concentration and flow velocity-influenced the community structure of macrobenthos by the redundancy analysis. (4) The biological index analysis results indicated that the water quality in the basin was lightly or moderately polluted, which varied significantly from the assessment of the physical and chemical factors of water quality. The comprehensive water and ecological quality index model calculations, which integrated biotic and abiotic factors, suggested an overall water and environmental quality preference for the basin. But some sampling points have been disturbed or polluted, which was basically consistent with the abundance-biomass comparison curves analysis and the dominant species analysis, in which the result of evaluation was more scientific and reliable. 参考文献 相似文献 引证文献

氮添加对红松人工林草本层植物多样性的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 氮添加对红松人工林草本层植物多样性的影响 DOI: 10.5846/stxb202110122873 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家科技基础资源调查专项（2019FY202300） Effects of nitrogen addition on species diversity of the understory plants in the Korean pine plantation 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:氮沉降是驱动生物多样性变化的重要因素之一。为了探索氮添加对红松（Pinus koraiensis）人工林草本层植物多样性的影响及其驱动机制，以黑龙江凉水国家级自然保护区红松人工林为研究对象，设置N0（对照处理，0 kg hm-2 a-1）、N20（低氮处理，20 kg hm-2 a-1）、N40（中氮处理，40 kg hm-2 a-1）和N80（高氮处理，80 kg hm-2 a-1）4个施氮水平，进行6年的氮添加实验。结果表明：（1）氮添加显著降低草本层3个功能群的密度和盖度，而对高度无显著影响；（2）6年氮添加使对照与施氮处理间群落相似度随施氮水平的增加而减小；（3）氮添加显著降低草本植物的丰富度和Shannon-Wiener多样性指数，而未对蕨类和木本植物的丰富度和Shannon-Wiener多样性指数产生显著影响，对草本层3个功能群的Pielou均匀度指数均无显著影响；（4）氮添加对草本植物的C、N、P含量、N：P、C：P产生显著影响，对木本植物的P含量、N：P、C：P产生显著影响，对蕨类植物的C：N：P生态化学计量均无显著影响；（5）草本植物多样性与土壤化学性质无显著的相关关系，草本植物丰富度、Shannon-Wiener多样性指数与植物盖度、密度呈显著的正相关关系，丰富度与植物N含量呈显著的负相关关系，Shannon-Wiener多样性指数与植物N：P呈显著的负相关关系。研究表明6年氮添加改变植物草本层中物种组成和群落结构，3个功能群密度和盖度显著降低，高度未产生显著变化，仅降低草本植物的丰富度和多样性。造成该现象的原因可能是，不同物种对于氮的利用特性和耐受程度存在差异，氮添加引起草本植物养分失衡，改变物种组成和群落结构，从而影响草本植物多样性。研究结果可为我国温带森林生态系统持续性管理提供数据和理论基础。 Abstract:Nitrogen deposition is one of the important driving factors of biodiversity change. To explore the effect of nitrogen addition on the understory plants diversity of the Korean pine (Pinus koraiensis) plantation and its driving mechanism, we simulated N deposition with four levels of N addition rate N0 (control treatment, 0 kg hm-2 a-1), N20 (low nitrogen treatment, 20 kg hm-2 a-1), N40 (medium nitrogen treatment, 40 kg hm-2 a-1) and N80 (high nitrogen treatment, 80 kg hm-2 a-1) for 6 years, based on the Korean pine plantation in Liangshui National Nature Reserve in Heilongjiang Province. The results showed that:(1) nitrogen addition significantly reduced the density and coverage of the three functional groups in the understory plants, but had no significant effect on the height. (2) The 6-year nitrogen addition reduced community similarity between control and nitrogen application treatment decreased with the increase of nitrogen application level. (3) Nitrogen addition significantly reduced the Shannon-Wiener diversity index and species richness of herbs in the Korean pine plantation. Nitrogen addition had no significant effect on the species richness and Shannon-Wiener diversity index of woody plants and ferns. Nitrogen addition had no significant effect on the Pielou evenness index of the three functional groups of herbs. (4) Nitrogen addition had significant effects on the contents of C, N, P, N:P and C:P of herbs. Nitrogen addition had significant effect on the contents of P, N:P and C:P of woody plants, and it had no significant effect on C:N:P ecological stoichiometry of ferns. (5) There was no significant correlation between herb diversity and soil chemical properties. There was significantly positive correlation between species richness of herbs, Shannon Wiener index and coverage, density of herbs. There was significantly negative correlation between species richness of herbs and plant N content, and between herb Shannon Wiener index and plant N:P. The 6-year nitrogen addition changed the species composition and community structure in the understory plants, significantly reduced the density and coverage of the three functional groups, and had no significant change on the height, and it only reduced the species richness and Shannon-Wiener diversity index of herbs. The reason for this phenomenon may be that different species have different nitrogen utilization characteristics and tolerance, and nitrogen addition causes nutrient imbalance of herbs, changes species composition and community structure, and affects herbs diversity. The results provide data and theoretical basis for the sustainable management in temperate forest ecosystems in China. 参考文献 相似文献 引证文献

基于环境DNA宏条形码技术的秦淮河生物多样性研究

秦淮河是南京的母亲河, 其生物多样性受城市化进程影响面临严重威胁, 而物种资源调研是生物多样性保护的基础。环境DNA宏条形码技术较形态学监测是一种简单高效、灵敏度高的新型监测技术。为探究秦淮河浮游生物、底栖动物及鱼类的生物多样性, 于2019年7月, 采用环境DNA宏条形码技术对其进行了探究, 并分析了秦淮河上下游间的差异及环境因子对其群落结构的影响。结果表明: 秦淮河共监测到浮游动物13属22种407个操作分类单元(Operational Taxonomic Units, OTUs), 浮游植物85属60种4445个OTUs, 底栖动物16属17种212个OTUs, 鱼类53属44种1663个OTUs。其中浮游动物以游泳轮虫目(Ploima)和双甲目(Diplostraca)为主, 共占浮游动物63.37%, 浮游植物以隐藻门(Cryptomonas)和褐藻门(Ochrophyta)为主, 共占浮游植物88.11%, 底栖动物中节肢动物门(Arthropoda)占比最高, 达91.67%, 鱼类中鲤形目(Cypriniformes)占比最高, 达69.99%。与秦淮河历史形态学监测数据相比, 环境DNA宏条形码技术在物种丰度鉴定方面显著高于传统形态学鉴定的物种丰度。通过主坐标分析和PERMANOVA检验, 发现秦淮河下游、上游南支和上游北支间有极显著差异(P < 0.001)。其中浮游动物、浮游植物和底栖动物受分组影响更大, 分组对鱼类的影响相对较小。下游α多样性较上游更为贫乏, 上游南支(南京)α多样性较上游北支(句容)更丰富。浮游生物和底栖动物均表现出了明显的随距离增加而衰减的趋势。冗余分析表明, 较低营养级的生物对环境因子的变化更为敏感, 浮游生物和底栖动物的主要影响因子为总氮、总有机碳、总磷、氨氮、化学需氧量和溶解氧。鱼类的影响因子为溶解氧、总有机碳、总氮、总磷和化学需氧量。研究通过对秦淮河生物多样性的调研, 可为秦淮河的生物多样性保护提供理论参考。;Qinhuai River is the mother river of Nanjing, and its biodiversity is seriously threatened by the process of urbanization. The survey of species resources is the basis of biodiversity protection. Compared with morphological monitoring, the environmental DNA metabacroding is a simple, efficient and sensitive new monitoring technology. In order to explore the biodiversity of plankton, zoobenthos and fish in Qinhuai River, the environmental DNA metabacroding was used to explore it in July 2019, the differences between upstream and downstream of Qinhuai River were analyzed, and the relationship between the community composition of Qinhuai River and environmental variables was evaluated. The results showed that a total of 13 genus, 22 species and 407 operational taxonomic units (OTUs) of zooplankton, 85 gennus, 60 species and 4445 OTUs of phytoplankton, 16 genus, 17 species and 212 OTUs of zoobenthos, 53 genus, 44 species and 1663 OTUs were detected through the environmental DNA metabacroding. Among them, Ploima and Diplostraca, accounting for 63.37%, were dominant species in zooplankton community at the order level. The most abundant species in phytoplankton community at the phylum level were Cryptomonas and Ochrophyta, accounting for 88.11%. The zoobenthos were dominated by Arthropoda at the phylum level, which accounted for 91.67%. The Cypriniformes accounting for 69.99%, were dominants in fish of different samples at the order level. Compared with the historically morphological monitoring data of Qinhuai River, the environmental DNA metabarcoding technique was more powerful than the morphological method in assessment of species richness. Through the principal coordinate analysis (PCoA) and PERMANOVA test, a significant difference (P < 0.001) was found among downstream, the south branch of upstream and the north branch of upstream of Qinhuai River. Zooplankton, phytoplankton and zoobenthos were more affected by the group of sites than fish. Alpha(α) diversity of downstream in Qinhuai River was poorer than that of upstream, and Alpha(α) diversity of the south branch of upstream (Nanjing) was richer than that of the north branch (Jurong). All of the taxa of Qinhuai River except fish showed strong relationship between geographical distance (km) and biotic community similarity based on Bray-Curtis distance. Redundancy analysis (RDA) showed that organisms with lower trophic levels were more sensitive to changes in the environmental factors. The main influencing factors in plankton and zoobenthos community distribution were total nitrogen (TN), total organic carbon (TOC), total phosphorus (TP), ammonia nitrogen (NH₃-N), chemical oxygen demand (COD) and dissolved oxygen (DO). While the key factors in fish community distribution were DO, TOC, TN, TP and COD. Our results can provide a theoretical reference for the protection of the biodiversity of Qinhuai River.

Ecological diversity of Phylloplane Mycoflora of medicinal plants in Naharlagun, Papumpare District, Arunachal Pradesh, India

Leaves constitute the major part of exposed plant surface. They are open to infestation or sporotropic colonization by air dispersed or splash dispersed mycoflora. The leaves provide unique environment to their surface occupants. The topography of the leaf surface, the microclimate around the leaves and the typical leaf exudate influence the growth and development of varieties of leaf surface micro-organisms and in turn determine the vitality of the plant concerned. In this context survey on the occurrence of Phylloplane fungi on leaf surfaces of eight important medicinal plants viz; Catharanthus roseus (L.) G.Don, Houttuynia cordata Thunb., Solanum lycopersicum Lam., Murraya koenigii (L.) Spreng., Eryngium foetidum L., Clerodendrum glandulosum Lindl., Ocimum sanctum, Capsicum chinense Jacq. From the present study it is being concluded that most abundant phylloplane fungi are Alternaria sp, Penicillium sp, and Aspergillus sp with high value of relative abundance. The number of identified fungal strains were analyzed to obtain relative abundance, species richness, evenness, Shannon Wiener diversity index, Simpson dominance index, and community similarity index. The Shannon Wiener diversity index, Simpson dominance index species richness index, species evenness index was estimated high in Solanum lycopersicum followed by Houttuynia cordata, Ocimum sp, Eryngium foetidum etc. In all the selected medicinal plants same fungal community structure was obtained based on the calculation of similarity index.

Vegetation analysis of the Forest Park of Pocut Meurah Intan (THRPMI), Seulawah Subdistrict, Aceh Besar, Aceh Province

A study entitled “Vegetation Analysis of the Forest Park of Pocut Meurah Intan, Seulawah Subdistrict of Aceh Besar, Aceh Province” has been conducted since April 2019 until November 2019. A transect method and squares were used in this study. The transect method was used to record species composition throughout the observation stations (inventory of species), including stands of pine (Pinus merkusii) with ten stations transect, stands of eucalyptus (Eucalyptus urophylla), stands of cacao (Theobroma cacao), and natural forests within a radius of 2 km around the THRPMI office. The squares method was used to record the species in the same locations to replicate each station by ten squares of samples for vegetation analysis. The parameters measured in the field were frequency, density, and dominance of each species. Analysis of vegetation covered Importance Values (IV), Diversity Index (H ’), and the Similarity Index (SI). Results showed that there were 49 familia found with the composition of species in the entire observation stations comprising of 111 species with 58 species of trees, 12 species of shrubs, and 41 species of herbs. Additionally, the results showed that the species of vegetation with the highest IV were coarse grass (Imperata cylindrica), lawn pait (Axonopus compresus), and selasi (Vernonia cinerea) with IV of 72.01, 65.34, and 57.24, respectively. Results of analysis Species Diversity Index (H ’) showed that the Pinus merkusii had H’ of 2,134, whereas Eucalyptus urophylla had H ’of 1.965, and Theobroma cacao had H’ of 1,067. The results of the analysis of Community Similarity Index showed that all stations had the same relative SI of 75%. It can be concluded that the species composition of the study area dominated by tree species, species diversity index (H ’) in all observation stations varied ranging from 1.067 to 2.134, and the relative Community Similarity Index was 75%.

CO2 biogeochemical investigation and microbial characterization of red wood ant mounds in a Southern Europe montane forest

Red wood ants are ecologically important species in Europe that form large colonies. Their nest mounds are characterized by stable microclimatic conditions, that are favourable to the development of rich invertebrate and microbial communities. Through their respiration processes, all these inhabitants contribute to the total gas emissions of the mounds. Quantifications of red wood ant mounds CO2 production are only available from Northern and Central Europe, and the Alps, where these ants are common. During the second half of the last century some species were transplanted from the Alps to southernmost sites, where they were not present, to be employed as biocontrol agents. No information on the contribution of these low-latitudes populations to the local forest CO2 production is available. The microbial communities living within red wood ant mounds are also poorly known. In this study, we investigated the CO2 gas emissions and the microbiome of the mounds of an introduced population of the red wood ant Formica paralugubris in a Southern Europe montane forest. We found that ant mounds produced more CO2 than the forest soil, and that their CO2 efflux as well as internal concentration were higher during summer than winter, with a lighter CO2 carbon isotopic signature in summer than winter, likely due to an increased ant activity. Moreover, the top part of the mound was characterised by higher CO2 efflux and lower CO2 internal concentration compared to the bottom, probably due to its internal structure and conditions. The isotopic signature of the mound material was similar between summer and winter, suggesting a metabolic similarity of the microbial communities. Also, we estimated the ants’ relative contribution to the total mound CO2 production to be 83%, whereas the microbiota CO2 contribution was estimated at 17%. Finally, the mound microbiome composition varied between summer and winter, though no seasonal difference in the diversity indexes or β-diversity was found. Our results demonstrate the impacts of the introduced red wood ants on the carbon dynamics of the recipient ecosystem.

Flooding and ecological restoration promote wetland microbial communities and soil functions on former cranberry farmland.

Microbial communities are early responders to wetland degradation, and instrumental players in the reversal of this degradation. However, our understanding of soil microbial community structure and function throughout wetland development remains incomplete. We conducted a survey across cranberry farms, young retired farms, old retired farms, flooded former farms, ecologically restored former farms, and natural reference wetlands with no history of cranberry farming. We investigated the relationship between the microbial community and soil characteristics that restoration intends to maximize, such as soil organic matter, cation exchange capacity and denitrification potential. Among the five treatments considered, flooded and restored sites had the highest prokaryote and microeukaryote community similarity to natural wetlands. In contrast, young retired sites had similar communities to farms, and old retired sites failed to develop wetland microbial communities or functions. Canonical analysis of principal coordinates revealed that soil variables, in particular potassium base saturation, sodium, and denitrification potential, explained 45% of the variation in prokaryote communities and 44% of the variation in microeukaryote communities, segregating soil samples into two clouds in ordination space: farm, old retired and young retired sites on one side and restored, flooded, and natural sites on the other. Heat trees revealed possible prokaryotic (Gemmatimonadetes) and microeukaryotic (Rhizaria) indicators of wetland development, along with a drop in the dominance of Nucletmycea in restored sites, a class that includes suspected mycorrhizal symbionts of the cranberry crop. Flooded sites showed the strongest evidence of wetland development, with triple the soil organic matter accumulation, double the cation exchange capacity, and seventy times the denitrification potential compared to farms. However, given that flooding does not promote any of the watershed or habitat benefits as ecological restoration, we suggest that flooding can be used to stimulate beneficial microbial communities and soil functions during the restoration waiting period, or when restoration is not an option.

Invasion and defense of the basic social unit in a nonhuman primate society leads to sexual differences in the gut microbiome.

Multilevel society is one of the most complex social systems in natural ecosystems and is a typical feature among some primates. Given the potential connection between social behavior and gut microbiome composition, the multilevel social system could affect the primate gut microbiome. Here, based on long‐term observation (e.g. social unit dynamics, transfer, and behavior), we investigated this potential integrating 16S rRNA gene amplicon sequencing and behavior data in Yunnan snub‐nosed monkeys (Rhinopithecus bieti), which possess a multilevel social group based on one male units (OMUs, each unit with several breeding females and their offspring) and all‐male unit (AMU, several bachelor males residing together). We found that the mean unweighted Unifrac distance between adult males from different OMUs was significantly lower than that between adult females from different OMUs (paired Wilcoxon test, P = 0.007). There was no significant difference in the mean unweighted Unifrac distance between females within the same OMU or between females from different OMUs. These findings indicated the potential connection between the defense and invasion of social units and the gut microbiome community in wild Yunnan snub‐nosed monkeys. We speculated that the resident males of OMUs displaying a significantly higher similarity in the gut microbial community than that of adult females in separate OMUs might be associated with the sexual differences in their interactions and from previously having cohabitated together in the AMU. Therefore, this study suggested that multilevel societies might have an effect on the gut microbial community in this wild nonhuman primate species.

Continuous Cropping Changes the Composition and Diversity of Bacterial Communities: A Meta-Analysis in Nine Different Fields with Different Plant Cultivation

Chinese goldthread (Coptis chinensis Franch.) represents one of the most important medicinal plants with diverse medicinal applications, but it easily suffers from continuous cropping obstacles in the plantation. In this study, we have selected eight different continuously cropped fields with C. chinensis and fallow field, providing detailed information regarding the diversity and composition of the rhizospheric bacterial communities. We have found a significant difference between fallow field (LH) and other continuously cropped fields in soil pH; the total content of nitrogen, phosphorus, and potassium; and soil enzyme activities. The results indicate that continuous cropping had a significant effect on soil physicochemical properties and enzyme activities under different plant cultivations. The relative abundance of bacterial phyla was significantly altered among the fields; for example, proteobacteria and Actinobacteria were observed to be higher in continuous cropping of maize (HY6) and lower in sweet potato continuous cropping (HH). Alpha diversity analysis showed that different plants with different years of continuous cropping could change the diversity of bacterial communities, among which the effect of maize and Polygonum multiflorum continuous cropping were most significant. Principle coordinate analysis (PCoA) showed that continuously cropped C. chinensis (LZ) and cabbage continuously cropped for 2 years (HS) were slightly clustered together and separated from LH and others. The results showed that the similarity of the bacterial community in the same crop rotation was higher, which further indicated that the bacterial community structure was significantly altered by the continuous cropping system and plant species. Our study provides a foundation for future agricultural research to improve microbial activity and increase crops/cash-crops productivity under a continuous cropping system and mitigate continuous cropping obstacles.

Community similarity and species overlap between habitats provide insight into the deep reef refuge hypothesis

The deep reef refuge hypothesis (DRRH) postulates that mesophotic coral ecosystems (MCEs) may provide a refuge for shallow coral reefs (SCRs). Understanding this process is an important conservation tool given increasing threats to coral reefs. To establish a better framework to analyze the DRRH, we analyzed stony coral communities in American Sāmoa across MCEs and SCRs to describe the community similarity and species overlap to test the foundational assumption of the DRRH. We suggest a different approach to determine species as depth specialists or generalists that changes the conceptual role of MCEs and emphasizes their importance in conservation planning regardless of their role as a refuge or not. This further encourages a reconsideration of a broader framework for the DRRH. We found 12 species of corals exclusively on MCEs and 183 exclusively on SCRs with another 63 species overlapping between depth zones. Of these, 19 appear to have the greatest potential to serve as reseeding species. Two additional species are listed under the U.S. Endangered Species Act, Acropora speciosa and Fimbriaphyllia paradivisa categorized as an occasional deep specialist and a deep exclusive species, respectively. Based on the community distinctiveness and minimal species overlap of SCR and MCE communities, we propose a broader framework by evaluating species overlap across coral reef habitats. This provides an opportunity to consider the opposite of the DRRH where SCRs support MCEs.

Mechanism of Saline–Alkali land improvement using subsurface pipe and vertical well drainage measures and its response to agricultural soil ecosystem

Salinization is recognized as a threat to agricultural productivity and land resources in global arid desert regions. To date, field soil improvement schemes have met with minimal success to date. We aimed to improve saline–alkali soils by assessing the effects of combining subsurface pipe (Pa) and vertical well (Sa) drainage measures on agricultural soils ecosystem. In a five-year field experiment, soil was sampled 0.5 m, 5 m, 7.5 m horizontally away from the Pa, and 0.5 m, 30 m, 60 m horizontally away from the Sa. Findings indicate that the soil electrical conductivity (EC) decreased from 16 dS m−1 to 3 dS m−1 at a 0–80 cm depth, and the soil desalination efficiency was great at the 0–300 cm depths (≥ 32%) than at the 400–700 cm depths (−14%–74.7%). The combined Pa and Sa drainage measures significantly decreased the species richness and quantity of soil microbial communities, and their negative impact on observed species was irreversible within 1 year. The farther the horizontal sampling conducted from the Pa and Sa, the greater the structural similarity of the microbial community at the genus level, higher the catalase, acidic protease, and neutral phosphatase activities, and lower the alkaline phosphatase activity. The overall decrease in groundwater level from 2016 to 2020 was 5.7 m. The seed cotton yield increased by 3.2 t ha−1. The results suggest that the value of saline–alkali soil can be improved by combining Pa and Sa drainage measures. Our research provides guidance for further effective utilization of agricultural water and soil resources and the sustainable development of the soil ecosystem in arid desert areas.

Non-native gobies share predominantly immature parasites with local fish hosts

Non-native species are known to escape their parasites following introduction into a new range, but they also often acquire local parasites as a function of time since establishment. We compared the parasite faunas of five non-native Ponto-Caspian gobies (Gobiidae) and local fish species (Perca fluviatilis, Gymnocephalus cernua, Gobio gobio) in three European river systems; the Rivers Rhine, Vistula and Morava, where Ponto-Caspian gobies were introduced 4-13 years prior to the study. Overall parasite species richness was considerably lower in non-native gobies compared to local fish species, and the same result was found at the component and infra-community levels. Both parasite abundance and diversity greatly varied among the regions, with the highest values found in the River Vistula (Wloclawski Reservoir), compared to a relatively impoverished parasite fauna in the River Morava (Danube basin). While only half of parasite species found in local hosts were acquired by non-native gobies, most of the parasites found in gobies were shared with local fish species related either phylogenetically (percids) or ecologically (benthic gudgeon), including the co-introduced monogenean Gyrodactylus proterorhini. As a result, similarity in parasite communities strongly reflected regional affiliation, while phylogenetic distances between fish host species did not play a significant role in parasite community composition. In accordance with other studies, all parasites acquired by gobies in their new range were generalists, all of them infecting fish at the larval/subadult stage, indicating the possible importance of gobies in the life cycle of euryxenous parasites. The absence of adult generalists, particularly ectoparasites with low host specificity, in non-native fish may reflect their generally low abundance in the environment, while an absence of adult endoparasitic generalists was probably related to other factors.