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1.
Disturbance plays an integral part in generating heterogeneity required for ecosystem persistence, but the increased amplitude and duration of disturbances linked to drivers of global change could result in ecosystem shifts or collapse. Biomonitoring over time provides insights into trajectories of ecosystem change. The responses of two instream animal taxa to two contrasting disturbance events, a major flood event and the long-term cumulative effects of land-use changes, were assessed in 1999–2012 by quantifying variation and change in abundance of functional groups based on flow rate sensitivity, water quality and metrics of ecological condition. All metrics recovered to pre-flood conditions within seven months after the flood event. Similarly, cumulative impacts of land use effected significant decreases in some but not all metrics. Indices that did not change, including SASS total score and ASPT, were the result of insufficient consideration of the decrease in the abundance of sensitive taxa specifically, and the abundance of all taxa in general. The decrease in abundance of sensitive taxa could signal imminent collapse in certain metrics. Evidence is also provided for a shift in the structure of fish assemblages linked to the decrease and loss of taxa sensitive to ecosystem degradation caused by the longer-term impacts of land-use change.  相似文献   
2.
Many colobine species—including the endangered Guizhou snub‐nosed monkey (Rhinopithecus brelichi) are difficult to maintain in captivity and frequently exhibit gastrointestinal (GI) problems. GI problems are commonly linked to alterations in the gut microbiota, which lead us to examine the gut microbial communities of wild and captive R. brelichi. We used high‐throughput sequencing of the 16S rRNA gene to compare the gut microbiota of wild (N = 7) and captive (N = 8) R. brelichi. Wild monkeys exhibited increased gut microbial diversity based on the Chao1 but not Shannon diversity metric and greater relative abundances of bacteria in the Lachnospiraceae and Ruminococcaceae families. Microbes in these families digest complex plant materials and produce butyrate, a short chain fatty acid critical to colonocyte health. Captive monkeys had greater relative abundances of Prevotella and Bacteroides species, which degrade simple sugars and carbohydrates, like those present in fruits and cornmeal, two staples of the captive R. brelichi diet. Captive monkeys also had a greater abundance of Akkermansia species, a microbe that can thrive in the face of host malnutrition. Taken together, these findings suggest that poor health in captive R. brelichi may be linked to diet and an altered gut microbiota.  相似文献   
3.
甘肃黄芪属药用植物资源   总被引:17,自引:0,他引:17  
目的:调查甘肃省黄芪属药用植物资源,为该属植物资源的开发利用提供科学依据.方法:深入甘肃各地进行实地调查、采集标本和分类鉴定,并查阅和核对主要标本馆的腊叶标本.结果:初步研究,甘肃省有13种1亚种药用黄芪属植物,记述了它们在省内的分布、生境和药用价值,并编制了检索表.结论:甘肃黄芪属植物资源丰富,有待进一步研究,开发利用.  相似文献   
4.
浙江中部地区野榧的调查   总被引:1,自引:0,他引:1  
简述了浙江中部地区被称为"野榧"的植物,并非指一种植物,而是三尖杉、南方红豆杉、粗榧和野生榧树等几种植物.同时介绍了它们的叶与果实的主要区别;指出这些重要野生植物资源应加以保护.  相似文献   
5.
报道黔北毕节、仁怀和石阡地区晚奥陶世Hirnantian期观音桥层中首次发现的四射珊瑚Axiphoria,Bodophyllum,Dalmanophyllum,Leolasma,Brachyelasmaunicum(Neuman),Grewingkiaanguinea(Scheffen),结合前人报道的该层所产的Borelasma,Kenophyllum,Streptelasma,Ullernelasma等属,进一步表明黔北观音桥层四射珊瑚动物群与斯堪的纳维亚(Scandinavia)、中亚、阿尔泰地区同期珊瑚群关系密切。该动物群对阐明晚奥陶世四射珊瑚古地理关系具有重要意义。黔北观音桥层四射珊瑚十分丰富,总计有18属39种。文中共描述10属12种,其中1新属3新种,即AmplexobrachyelasmaHeetChengen.nov.,GrewingkiadensicolumnaHeetChensp.nov.,KenophyllumfossulatumHeetChensp.nov.,LeolasmaqianbeienseHeetChensp.nov.。  相似文献   
6.
桂西和黔南中三叠世珊瑚   总被引:1,自引:0,他引:1  
文内描述中三叠世安尼阶(Anisian)珊瑚化石分别采自桂西田阳板纳组和黔南贵阳青岩青岩组。板纳组珊瑚群中建立Pentasmilia guangxiensisgen.etsp.nov.,该新属种有5条第一周期原生隔片甚至有5条第二周期后生隔片,以此不同于有6条第一周期原生隔片和有6条第二周期后生隔片的石珊瑚类(scleractinians)的珊瑚。产于板纳组的另一新属种Radiophyllia astylatusgen.etsp.nov.,其隔片的排列格式与前人归纳的隔片周期插入示意图甚似,但它却发生在中生代最早期(Anisian)珊瑚的骸体内。文中还对青岩组的Pamiroseris silesiaca作了重新描述。  相似文献   
7.
2010年7月~2012年8月,在贵州省荔波南方喀斯特世界自然遗产地进行脊椎动物物种多样性调查时,分别在板寨、瑶山、翁昂和洞塘采集到游蛇科蛇类标本共5条,经分类鉴定为锦蛇属(Elaphe)的百花锦蛇(E.moellendorffi),为该物种在贵州省内首次发现,增加了其在国内的分布点.  相似文献   
8.
Sharka disease is one of the most damaging diseases of fruit trees in the world, which is caused by Plum pox virus (PPV) that belongs to the genus Potyvirus in the family Potyviridae. Each year, this virus decreases the yield and causes substantial economic damages to its host plants worldwide. This virus is quarantined in Iran but in recent years, suspicious symptoms of the disease were observed in different grown areas, such as Golestan province. During 2010, 420 samples with mosaic, chlorosis, necrosis, ring pattern, blotches, etc. symptoms were collected from the gardens in Golestan province that included 100 samples from plum, 100 from peach and 240 from nectarine. These samples were evaluated using a double-antibody sandwich-ELISA (DAS-ELISA) method and a polyclonal antibody. The results of this survey indicated that among the total of 420 samples, none of them showed positive reaction in DAS-ELISA test.  相似文献   
9.
生态系统生产总值核算:概念、核算方法与案例研究   总被引:26,自引:0,他引:26  
生态系统产品与服务功能是人类生存与发展的基础。生态系统生产总值(GEP)可以定义为生态系统为人类福祉和经济社会可持续发展提供的产品与服务价值的总和,包括生产系统产品价值、生态调节服务价值和生态文化服务价值。生态系统生产总值核算的基本任务有3个,即核算生态系统产品与服务的功能量、确定生态系统产品与服务的价格、核算生态系统产品与服务的价值量。生态系统生产总值核算可以用于揭示生态系统为经济社会发展和人类福祉的贡献,分析区域之间的生态关联,评估生态保护成效和效益。以贵州省为例,探讨了生态系统生产总值核算的应用方法,评价了贵州省生态系统为贵州和其他地区人们福祉和支撑经济社会发展所提供的产品和服务及其经济价值总和。评价结果显示,贵州省2010年全省生态系统生产总价值为20013.46亿元,人均GEP 57526元,是当年该省国民生产总值和人均GDP的4.3倍。研究表明,生态系统生产总值的核算可以反映生态系统对经济社会发展的支撑作用,并为建立生态系统保护效益与成效的考核机制提供基础。  相似文献   
10.
In 2007, the Chinese State Food and Drug Administration (SFDA) implemented a management system for lot release of all plasma-derived products. Since then, there have been only a few systematic studies of the blood supply, which is a concern when considering the small amount of plasma collected per capita (approximately 3 L/1000 people). As a result, there may be a threat to the safety of the available blood supply. In this study, we examined the characteristics of the supply of Chinese plasma-derived products. We investigated the reports of lot-released biological products derived from all 8 national or regional regulatory authorities in China from 2007 to 2011. The market supply characteristics of Chinese plasma-derived products were analyzed by reviewing the changes in supply varieties, the batches of lot-released plasma-derived products and the actual supply. As a result, the national regulatory authorities can more accurately develop a specific understanding of the production and quality management information provided by Chinese plasma product manufacturers. The implementation of the lot release system further ensures the clinical validity of the plasma-derived products in China and improves the safety of using plasma-derived products. This work provides an assessment of the future Chinese market supply of plasma-derived products and can function as a theoretical basis for the establishment of hemovigilance.  相似文献   
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