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1.
生态化学计量学理论最早应用在水生生态系统的研究中,但最近20年来在陆地生态系统中也开展了大量的相关研究,特别是关于全球变化背景下陆地植物N/P生态化学计量学方面的研究得到很大的发展,极大地丰富和提升了我们对陆地植物包括生态系统生态过程的认识。就全球变化背景下陆地植物生态化学计量学的研究现状进行了综述,同时以中国科学院华南植物园90周庆为契机,总结我们关于南亚热带森林植物生态化学计量学的研究工作,进而分析当前存在的一些问题并提出今后研究的发展重点,以期促进和推动我园和我国生态化学计量学相关领域的研究。  相似文献   

2.
Studies on large-scale geographic patterns of aquatic plant diversity can promote research on the generality of macroecological patterns in different ecosystems. Here, we compiled a checklist of 889 aquatic angiosperms in China, including 738 helophytes (emergent and marshy plants) and 151 hydrophytes (submerged, free-floating, and floating-leaved plants). We explore the geographic patterns and environmental correlates of aquatic plant diversity based on six metrics including species richness (SR), weighted endemism (WE), phylogenetic diversity (PD), phylogenetic endemism (PE), the standardized effect size of phylogenetic diversity (PDses), and the standardized effect size of mean phylogenetic distance (MPDses). Our results show that the diversity of aquatic plants in China is extremely uneven, with high diversity in southeastern China and low diversity in northwestern China, and the geographic patterns of taxonomic and PD are generally consistent. The pattern of helophytes differs from that of hydrophytes. Notably, the wavy-shaped pattern of aquatic plant diversity (especially SR and PD for hydrophytes) across the latitude observed in this study is not consistent with those previously observed for aquatic plants in other continents. Climatic variables and water environmental variables are the main drivers of aquatic plant diversity in China; however, the effects of individual variables differ between helophytes and hydrophytes. Water environmental variables have a greater impact on PDses and MPDses of hydrophytes than those of helophytes. Overall, our work provides insight into understanding the large-scale patterns of aquatic plant diversity and is a critical addition to previous studies on the macroecological pattern of terrestrial organisms.  相似文献   

3.
  1. Highlands are ideal research areas for improving our understanding of the influence of ecological factors on the diversity and spatial patterns of natural species. Elevation-driven physical and environmental isolation greatly affect the evolution of plants. The mechanisms and essential drivers underlying these processes may differ among research scales, habitats and landscapes. Wetlands are important elements of the Qinghai–Tibetan Plateau, which is the highest plateau in the world, and these habitats harbour high aquatic organismal diversity. However, how the environments shape the genetic variation and structure of hydrophilous plants is poorly understood.
  2. Using microsatellite markers and a chloroplast fragment, we quantified the genetic diversity and spatial genetic pattern of Stuckenia filiformis, one of the most widespread aquatic plants on the plateau. The relative contributions of geography, climate and local conditions to intra- and interpopulation variation were estimated. The results showed that intrapopulation genetic variation of the plant is moderate to high and not constrained by high-altitude environments. Topographical isolation mainly contributes to the genetic structure of S. filiformis, as inferred by simple sequence repeats and chloroplast DNA data. Significant effects of environmental variables on the spatial genetic patterns of this freshwater species were also suggested by landscape genetic analysis.
  3. Infrequent long-distance dispersal, sexual recruitment and annual growth are probably important for the maintenance and distribution of this variation. Our findings imply a combined effect of geography and elevation-driven environmental heterogeneity on the evolution of aquatic organisms in highlands.
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4.
武汉东湖水生植物区系四十年间的变化与分析   总被引:8,自引:3,他引:5  
本文根据作者近年的研究结果,并结合前人的有关研究资料,对东湖四十年间(1954-1994)水生植物区系组成变化进行了讨论。文中分析了东湖水生植物区系组成、东湖水生植物在中国与世界水生植物区系中的位置、东湖水生植物种属的分布区类型、单种属和寡种属的地理分布格局、东湖水生植物区系的性质、东湖与10个湖泊水生植物种属相似性的分析。最后对东湖水生植物分类群及种类变化进行了探讨。  相似文献   

5.
Duckweeds as crop plants Members of the plant family Lemnaceae (duckweeds) are not only interesting because they represent the smallest flowering plants; they possess also the fastest rates of producing biomass. As aquatic plants, duckweed production is not in competition with other agricultural crops that require fertile land while the cultivation of duckweeds does not contribute to further eutrophication of surface water. Instead, they can be cultivated on municipal or agricultural waste water and remove the nutrients during their propagation and growth. Duckweeds can thus be used for cleaning of waste water and the resulting biomass can be valuable starting material for animal feeds and the production of biofuels. Research focusing on these goals has begun to transfer from research laboratories to pilot plants in different parts of the world, e.g. in New Jersey and North Carolina, USA; Chengdu, P. R. China; and Armidale, Australia.  相似文献   

6.
野外采集和文献记载结果显示纳木错共有水生植物34种(变种),隶属于15科19属。其中,轮藻门植物1科1属1种、单子叶植物7科8属16种、双子叶植物7科10属17种。纳木错区水生植物区系整体上表现出鲜明的北温带性质。种联结分析表明纳木错水生植物种间相关性显著,这些种组构成一个连续体。样地调查显示,纳木错主要水生植物群落有11种,以沉水植物群落类型为主,兼有少量的浮叶植物群落。β-多样性测度表明,样地间种类组成随水环境差异变化明显。    相似文献   

7.
青藏高原湖泊纳木错水域生态学研究现状与展望   总被引:1,自引:0,他引:1  
徐军  康世昌 《生态科学》2010,29(3):298-305
青藏高原湖泊群是世界上海拔最高、分布最密的湖群区。藏北地区的纳木错是世界上海拔最高的大湖,同时也是我国仅次于青海湖的第二大咸水湖。在纳木错开展全面的水域生态学研究,对青藏高原湖群区具有重要借鉴和示范意义。论文综述了关于纳木错水域生态系统的已有研究。鉴于纳木错水域生态系统的基本特征尚未得到全面认识的现状,建议纳木错生态研究应集中在生物地球化学循环与食物网营养动力学研究、流域人类活动的生态学效应研究、纳木错生态系统对气候变化的响应、纳木错与藏北湖泊的比较湖沼学研究等几个范畴。  相似文献   

8.
东北水生植物区系与周缘地区水生植物区系关系的分析   总被引:2,自引:0,他引:2  
于丹 《植物研究》1994,14(4):401-408
本文在野外采集、查阅标本和文献考证的基础上,对东北地区水生植物区系与周缘地区水生植物区系的关系进行了初步分析。由于日本在地史起源上曾与大陆相连,且现代气候环境与东北地区的相似,故两者间水生植物的相似性系数最高O在更新世前古嫩辽河与结雅河相连通,使东北与远东地区间的水生植物得以相互交流,同时两区还保存有一些第三纪植物于遗种类,但因远东地区缺少东北暖温带气候,故一些东北产的暖温带种类未能分布该区,使其与东北水生植物种类相似性系数位于第二位。印度次大陆、澳大利亚、东南亚和非洲因与东北地区位于不同的气候带中,故水生植物种类相似性系数较低。在国内各地区中,以华北地区与东北地区水生植物的相似性系数最高,因两者过去同属古黄河水系,近代又接壤;相反,以与华南、台湾和海南岛的水生植物种类相似性系数最低。因相互间即存地理隔离,又无水系相通。  相似文献   

9.
Civilization is dependent upon plants for survival. Plants permeate our every moment and our relationship with them will dictate how we will manage the threats of climate change and ecological collapse defining the Anthropocene. Yet, despite the significance of plants and the critical role they have played in shaping ecosystems, civilizations, and human cultures, many people are now disconnected from the botanical world. Students are presented with little plant content, particularly identification, compared with animal content. Consequently, we are producing few plant scientists and educating fewer scientists about plants. This drives a self‐accelerating cycle we term the extinction of botanical education. A process of knowledge erosion, that in this instance contributes to our separation from the natural world, makes us blind to the biodiversity crisis and inhibits our ability to restore it. We argue that neglecting the importance of plants within education threatens the foundations of industries and professions that rely on this knowledge. Furthermore, this extinction of botanical education creates an existential threat: Without the skills to fully comprehend the scale of and solutions to human‐induced global change, how do we as a society combat it? We present key research agendas that will enable us to reverse the extinction of botanical education and highlight the critical role plants play on the global stage.

Civilization is dependent upon plants for survival and our relationship with them will dictate how we will manage the global impact of humanity which defines the Anthropocene. We document and define a self‐perpetuating educational cycle that we term the extinction of botanical education and its impact on the science of botany and potential ramifications for society to reverse and stabilise human included global change.  相似文献   

10.
11.
Aquatic plants fulfil a wide range of ecological roles, and make a substantial contribution to the structure, function and service provision of aquatic ecosystems. Given their well-documented importance in aquatic ecosystems, research into aquatic plants continues to blossom. The 14th International Symposium on Aquatic Plants, held in Edinburgh in September 2015, brought together 120 delegates from 28 countries and six continents. This special issue of Hydrobiologia includes a select number of papers on aspects of aquatic plants, covering a wide range of species, systems and issues. In this paper, we present an overview of current trends and future directions in aquatic plant research in the early twenty first century. Our understanding of aquatic plant biology, the range of scientific issues being addressed and the range of techniques available to researchers have all arguably never been greater; however, substantial challenges exist to the conservation and management of both aquatic plants and the ecosystems in which they are found. The range of countries and continents represented by conference delegates and authors of papers in the special issue illustrates the global relevance of aquatic plant research in the early twenty first century but also the many challenges that this burgeoning scientific discipline must address.  相似文献   

12.
Response and adaptation by plants to flooding stress   总被引:12,自引:0,他引:12  
Stress on plants imposed by flooding of the soil and deeper submergence constitutes one of the major abiotic constraints on growth, species' distribution and agricultural productivity. Flooding stress is also a strong driver of adaptive evolution. This has resulted in a wide range of biochemical, molecular and morphological adaptations that sanction growth and reproductive success under episodic or permanently flooded conditions that are highly damaging to the majority of plant species. However, even seemingly poorly adapted species possess some short-term resilience that is important for overall success of these plants in various habitats. The papers contained in this Special Issue address these topics and emphasize molecular, biochemical and developmental processes that impact on flooding tolerance. Most of the articles are based on lectures given to the 8th Conference of the International Society for Plant Anaerobiosis (ISPA), held at the University of Western Australia, Perth, 20-24 September, 2004. Reviews and research papers are presented from the leading laboratories currently working on plant responses to flooding stress.  相似文献   

13.
In this response to Labib and Evans, authors of the Hong Kong Principles look forward to collaborating with those from the broad research integrity community to ensure that issues of equity, diversity and inclusion will become part of the ecosystem of research integrity.

We thank Ms. Labib and Dr. Evans for their work on the Hong Kong Principles (HKPs) [1]. Your letter raises important points and gives us an opportunity to respond and clarify our perspective. As you indicate in your letter, equity, diversity, and inclusion (EDI) are important topics that require attention in the assessment of researchers. We did not address them specifically in the HKPs because our main focus was on rewarding responsible research practices that improve the transparency and validity of research. As a clarification (and not to be interpreted as defensive on our part), EDI also wasn’t mentioned prominently in our breakout discussions with more than 100 participants of the 6th World Conference on Research Integrity, where the draft HKPs were discussed and finalized.In our paper [2], Principle 5 (recognize essential other tasks like peer review and mentoring) provides a useful example that illustrates that the essence of the Labib and Evans comments about EDI are in alignment with our views—“Macquarie University, Sydney, Australia, has some exciting initiatives in their new academic promotion policy, which includes five pillars, one of which is in leadership and citizenship. Here, researchers can show their alignment with the university’s values and broader contribution to the university and its community [87]. Since this policy was introduced, it has been reported that the number of promotion applications increased by 50%, and the number of women promoted has also increased [88]”.We think there will be an opportunity to more forcefully address EDI in the envisioned Cape Town Statement on Fostering Research Integrity through equity, fairness, and diversity (programmed as a focus track on the 7th World Conference on Research Integrity, Cape Town, South Africa, 2022). We can imagine that the Cape Town Statement will demand fostering EDI in research, including in the assessment of researchers for hiring, promotion, or tenure. We would see this as an update of the HKPs.We are pleased that the HKPs has initiated discussion on EDI as part of the process of assessing researchers for hiring, promotion, and tenure. We look forward to collaborating with Labib and Evans and many others from the broad research integrity community to ensure that EDI will become part of the ecosystem of research integrity.  相似文献   

14.
居群(population)概念和方法在植物分类学中的应用   总被引:15,自引:1,他引:15  
本文依据我们近几年来对水生维管束植物的研究成果,讨论了居群概念和方法对植物分类学的理论和实际的意义与价值,同时对我国今后展开植物学研究提出了若干建议。  相似文献   

15.
Understanding the carbon sources supporting aquatic consumers in large rivers is essential for the protection of ecological integrity and for wildlife management. The relative importance of terrestrial and algal carbon to the aquatic food webs is still under intensive debate. The Yangtze River is the largest river in China and the third longest river in the world. The completion of the Three Gorges Dam (TGD) in 2003 has significantly altered the hydrological regime of the middle Yangtze River, but its immediate impact on carbon sources supporting the river food web is unknown. In this study, potential production sources from riparian and the main river channel, and selected aquatic consumers (invertebrates and fish) at an upstream constricted-channel site (Luoqi), a midstream estuarine site (Huanghua) and a near dam limnetic site (Maoping) of the TGD were collected for stable isotope (δ13C and δ15N) and IsoSource analyses. Model estimates indicated that terrestrial plants were the dominant carbon sources supporting the consumer taxa at the three study sites. Algal production appeared to play a supplemental role in supporting consumer production. The contribution from C4 plants was more important than that of C3 plants at the upstream site while C3 plants were the more important carbon source to the consumers at the two impacted sites (Huanghua and Maoping), particularly at the midstream site. There was no trend of increase in the contribution of autochthonous production from the upstream to the downstream sites as the flow rate decreased dramatically along the main river channel due to the construction of TGD. Our findings, along with recent studies in rivers and lakes, are contradictory to studies that demonstrate the importance of algal carbon in the aquatic food web. Differences in system geomorphology, hydrology, habitat heterogeneity, and land use may account for these contradictory findings reported in various studies.  相似文献   

16.
More than 130 delegates from all over the world attended the 1(st) Central and Eastern European Proteomic Conference organized together with the 3(rd) Czech Proteomic Conference in the TOP Hotel, Prague in the Czech Republic from 29(th) to 31(st) October, 2007. The autumn nostalgia of the historical city of Prague provided the stage for a fascinating meeting that reviewed rapidly emerging proteomic research in the countries of Central and Eastern Europe, and focused on proteomics driven discovery and applications.  相似文献   

17.
The Yangtze River is the largest river in China. It is a priority conservation area for biodiversity of the world, with its main river, branches and wetlands. As an essential part of freshwater ecosystem, aquatic vegetation has been well studied by Chinese researchers since 1950s, but large-scaled analysis on the biodiversity pattern is lacked. Based on published studies, we analyzed spatial and temporal pattern of aquatic plant diversity in the Yangtze River Basin, and calculated the suitable habitat area and underlying influence of environmental factors using MaxEnt software. A total of 298 species are recognized, belonging to 121 genera in 52 families, which is 57.6% of the total aquatic vascular plants in China. The Yangtze River Basin is the key area for aquatic plant diversity of China, especially the subregions of middle reaches. The elevation and land use are the key environmental variables to the spatial pattern of aquatic plants. The separation among water systems have weak influence on the spatial pattern of diversity in aquatic vascular plants, but potamo-lacustrine habitats facilitated the species homogenization of the flora in a sub-basin scale. The network consists of Poyang Lake, Dongting Lake, Tai Lake, and the middle and lower mainstream is the suitable area for the aquatic plants based on the MaxEnt model. In the past half century, the decline or loss of aquatic vegetation occurred in plenty of lakes in the Yangtze River Basin. We suggested that the protection of aquatic vegetation should be incorporated into the integrated conservation of the middle and lower Yangtze River. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.  相似文献   

18.
  1. To test hypotheses concerning the applicability of the Rapoport effect (RE: “species that occur at higher latitudes tend to have greater geographical range-size than species which have ranges limited to latitudes closer to the equator”) to aquatic macrophytes at global scale, we analysed the world latitudinal distribution and range-size of 1,083 vascular aquatic macrophyte species, from 91 genera in 11 families. We targeted macrophyte families strongly associated with inland aquatic habitats (i.e. with a zero, or only very low, proportion of constituent species which occur also in non-aquatic habitats), and which are distributed across a substantial latitudinal gradient, a necessary condition to test our hypotheses.
  2. The macrophyte species present in these families include plants from all the normally accepted life form-defined functional groups of macrophytes, namely submerged, free-floating, floating-leaf rooted and emergent species, and represent the three major vascular taxonomic groups occurring as aquatic macrophytes (ferns/fern allies, monocots, and dicots). For the analysis, we used both latitude-only and areal measures of macrophyte species geographic range-size, within a 10 × 10° (latitude × longitude) grid of 238 grid cells, covering the six world ecozones (Palaearctic, Orient, Australasia, Nearctic, Neotropics, Afrotropics) that primarily contain inland freshwater and brackish macrophyte habitats.
  3. The results provide new insight into the relationships between global range-size of macrophytes, latitude, and other potential spatio-environmental and anthropogenic drivers acting upon these plants at world scale. In particular, the outcomes indicated that: (1) the range-size versus latitude distribution of macrophytes shows evidence of a strong RE influence, with significantly greater species range-size at higher latitudes; and (2) the β-diversity pattern of species distribution along this latitudinal gradient is poorly explained by nestedness organisation, and species turnover is a more likely explanation of the observed changes in species distribution with latitude.
  4. Spatio-environmental and anthropogenic variables other than latitude may also influence the observed global geographical pattern of macrophyte range-size, although their importance as predictors varies between individual families. Extent of agricultural land use, altitude, and historic (post-Quaternary) climate change velocity were all significant predictor variables for some families. However, interestingly, neither the area of land nor the area of waterbody present per grid cell were major influences on macrophyte range-size distribution.
  5. Our finding of evidence for an RE, acting at global scale in aquatic macrophytes, contributes to increasing the generality of conclusions so far reached about the large-scale factors that drive patterns of species range-size at global scale. The study also provides a baseline for future macroecological work on aquatic plants, and potentially other freshwater organisms, particularly in the context of predicting how the world ranges of freshwater biota will respond to ongoing global environmental change.
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19.
我国和世蓝浆果的发展前景   总被引:24,自引:2,他引:22  
蓝浆果是具独特保健作用、生食加工皆宜的适于我国红黄壤地区开发的新兴经济作物。通过对美国一些研究机构和苗圃的考察及参加在智利举行的第七届国际蓝浆果研讨会,对目前世界蓝浆果的发展状况、趋势及一些最新研究成果作了概述,对我国发展蓝浆果的前景、方向等进行了讨论。  相似文献   

20.
In this paper an experiment in the application of LANDSAT MSS digital image proces. sing technique to classify the aquatic plants in the Honghu Lake, China, as well as the necessary ground feature spectrum measurement and plant chlorophyll content determination techniques are introduced. In order to obtain the expected computer aided classification result different methods of digital image feature extraction have been tried, namely the ratio transformation, the biomass index transformation and the linear stretching of image intensity. The data from spectrum measurement and chlorophyll content determination were used to distinguish the attributions of different classes of aquatic plant associations from one another by comparing with their spectrum response intensity values on different LANDSAT band images. The original LANDSAT MSS images were digitally rectified by control points to a certain map projection system using a general polynomial approach scheme before the classifying activities, so that the classification result may be transfered to an existing map. In this paper the resulting colourassigued image and the thematic map of Honghu Lakes aquatic plant (association) distribution are included, the areas of different classes of aquatic plants are listed and the reliability of the resulting classification and pattern recognition are analysed. These results will provide useful informations for the investigation of the present situation as well as the historical succession of the Honghu Lake and its aquatic plant distribution, and also for the research works of the lake management.  相似文献   

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