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1.
The elementary traits and diversity of embryonic setal patterns of 31 species of 22 genera, in three tribes of Hormaphidinae are studied. The embryonic setal patterns to every species are provided. Based on the parsimony principle and the developmental principle, these patterns are analyzed in each tribe following the terminology of Richards (1965). It is suggested that the setal patterns of abdominal tergites are the most important characters in embryonic and adult setal patterns. In conclusion, neoteny is a phylogenetic trend in the Hormaphidinae. Nipponaphidini and Hormaphidini have more typical neoteny in each genus and more diversity in different types of adult viviparous females than Cerataphidini, by showing more frequent and various protopatterns or mesopatterns.  相似文献   

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3.
The genus Helina R.-D., 1830 is the second largest genus in Muscidae. By now,more than 400 species are known in the world and about 200 species have been described in China. This paper outlines earlier studies on the subgenus and species-group of Helina. Helina annosa species-group is erected. A key to the known Chinese subgroups and species is given.The 19 known Chinese species is listed, including one new species, i.e. Helina setipostitibia sp. nov. Type specimen of the holotype of the new species is deposited in the Institute of Entomology, Shenyang Normal University.  相似文献   

4.
This work is a preliminary study on the Chinese species of the familyMniaceae,there are about 12 genera and more than 100 species of this familyhave thus far been discovered in the world.This family is a representativeplant group of the Temperate Zones of the Northern Hemisphere.It is mostwidely distributed in the Eastern Asia,especially in China.  相似文献   

5.
Responses of photosynthesis and the partition of energy utilization to high-nitrogen importation and high-light intensity in leaves of three dominant tree species of subtropical forest,including sun plant or early-successional species Schima superba,mesophyte or intermediate-successional species Canstanopsis hystrix,and shading-tolerant plant or late-successional species Cryptocarya concinna were studied by using the CO2 exchange system and chlorophyll fluorescence method.Our results showed that,regardless of plant species,net photosynthetic rate(Pn)was higher in high-nitrogen supply and high irradiance(HNHL)plants than in low-nitrogen supply and high irradiance(LNHL)plants,implying that low-nitrogen importation would limit Pn of plants grown under high irradiance.However, high-nitrogen supply and low irradiance(HNLL)plants had a lower Pn.Insignificant change of quantum yield(Fv′/Fm′)in opened PS II was found in leaves of HNHL,LNHL or HNLL plants of S.superba and C. hystrix,while a higher Fv′/Fm′occurred in HNHL plants of C.concinna in comparison with LNHL or HNLL plants.The HNHL plants of C.concinna also had a higher photochemical quantum yield(△F/Fm′) than LNHL or HNLL plants,however no similar responses were found in plants of S.superba and C. hystrix(P<0.05).In the irradiance range of 0―2000μmol photon·m -2·s -1,the fraction of energy consumed by photochemistry(φ PSII )was 18.2%in LNHL plants of S.superba which was higher than that in HNHL plants(P>0.05)and it was significantly higher than in HNLL plants(P<0.05).C.hystrix also had a similar response inφ PSII to nitrogen supply and irradiance.Regardless of species HNLL plants had a significantφ PSII and higher heat dissipation in light,and this effect was more severe in C.concinna than in S.superba or C.hystrix.The results may mean that high-nitrogen importation by nitrogen deposit and low irradiance caused by changing climate or air pollution would more severely restrict photosynthetic processes in the late-successional species C.concinna than in the early-successional species S.superba and intermediate-successional species C.hystrix.The continuous high-nitrogen precipitation in the future and the over cast mist or pollution smoke could induce late-successional species to degrade,however,early-successional species would be more adapted to competition for more resources to keep their dominance in ecosystems.In this sense,the zonal vegetation may accelerate degradation caused by high nitrogen precipitation and low irradiance,while the early-successional and mesophytic vegetations can remain longer.Thus,nitrogen precipitation may play an important role in plant community succession.  相似文献   

6.
《动物分类学报》2017,(1):71-89
Despite plenty of data in insects shape variation,papers on environmental factors effect on such variation are scarce and in ground beetles are practically absent.The aim of this research was to:(i) model the effect of the region of habitation,urbanization and habitat vegetation into the shape variation in widespread carabid species;(ii) describe sexual shape dimorphism in studied species.Samples were pitfall trapped in different regions of its area in the spectrum of anthropogenic influence (cities,suburbs,natural biotopes).One thousand and one hundred sixty-eight specimens were analyzed for six morphometric traits and terminal points of those measurements were used as landmarks for Procrustes analysis.We used linear models to reveal which factor (region,urbanization or vegetation) and in what direction affected beetles shape.Results showed that males in C.granulatus had more convex elytra and head,and the more convex in apical-basal direction pronotum.In its area from the east to the west elytra flattened in medial-distal direction and pronotum flattened in apical-distal direction.In disturbed urban environment beetles pronotum became more convex in both sexes and males elytra became more convex too.In open habitats (meadows,lawns) beetles became more flattened.  相似文献   

7.
A molecular phylogenetic analysis of most of the species of Perezia reveals that, as traditionally defined, the genus is not monophyletic with two species more closely related to Nassauvia than to Perezia. In addition, our results show that Burkartia (Perezia) lanigera is related to Acourtia and is the only member of that clade in South America. The remaining species are monophyletic and show a pattern of an early split between a western temperate and an eastern subtropical clade of species. Within the western clade, the phylogeny indicates a pattern of diversification that proceeded from southern, comparatively low-elevation habitats to southern high-elevation habitats, and ultimately into more northern high-elevation habitats. The most derived clades are found in the high central Andes, where significant radiation has occurred.  相似文献   

8.
Concentrations and ratios of nutrients in Jiaozhou Bay, China, have changed much in the past decades, with trends indicating an increase in nitrogen and a decrease in silicate. Statistical analysis has shown that the long-term variations of nutrients are associated with agricultural activities, precipitation, and anthropogenic factors. Stoichiometric calculations indicate that the nutrient structure has become more and more unbalanced. There has been almost no possibility for nitrogen limitation since the 1980s, the probability of P limitation has increased, and the probability of Si limitation has also increased markedly from the 1980s to the 1990s. As a consequence of changes in nutrient structure, a decrease in the abundance of net phytoplankton was evident, whereas total chlorophyll a levels have remained roughly unchanged at around 3.55μg/L. Thus, it is likely that smaller species have taken the niche vacated by the larger species. Changes in phytoplankton size and species composition may ultimately lead to various functional and structural changes at the system level.  相似文献   

9.
Y.T.Hou 《古生物学报》1955,(3):226-244
The materials which form the subject of the present paper was collected fromthe Upper Devonian Hsiehkingssu formation of Changyang district,W.Hupeh.The majority of the ostracods are more or less ironized,and are usually wellpreserved.The specimens illustrated and described in this paper comprise 15 species in11 genera,of them 4 genera and 11 species are new.The Hsiehkingsuu formation of Changyang district of Hupeh is estimatedabout 30 meters in thickness.The ostracods obtained from the thin-bedded and  相似文献   

10.
Energy storage is an important component in the life history of species that directly influences survival and reproduction. The energetic demands of amphibian reproduction can differ between the sexes, with environmental conditions, reproductive pattern or process of the species, and depending upon the timing of breeding, and the reproductive season for a species. Surprisingly, comparative studies of pre-hibernation energy storage for anuran populations from different latitudes are relatively few in Asia, especially in China. Here we investigated the patterns of pre-hibernation energy storage of Heilongjiang brown frogs Rana amurensis, based on five populations along a finely latitudinal gradient in north China(40.7–43.7°N). We found that pre-hibernation energy storage of the frogs did not show a clear latitudinal cline, but differed strongly between the sexes, with males depositing more energy reserves into the muscle and liver, whereas females accumulate more energy in the gonads. The sexual differences in energy storage may result from differential timing of energy allocation for reproduction.  相似文献   

11.
高俊峰  张志明  蔡永久  黄佳聪 《生态学报》2022,42(14):5677-5691
我国目前处于生态环境管理的转型期,尚未形成统领水生生物、生物栖息地、水质与水量等要素的水生态保护体系。在总结相关水生态研究成果的基础上,梳理形成了基于水生态系统时空尺度和状态梯度效应理论的水生态保护目标制定构想与方法,分析了淡水生物完整性对自然地理要素、水环境压力、栖息地质量的响应机制,提出以水生态“功能分区-状态评价-问题诊断-目标预设-可达性评估-目标确定”为主线的水生态保护目标制定技术体系,研发了生物完整性评价、水生态保护目标预设和可达性分析等技术方法。以江苏省常州市为典型水生态功能区应用案例,验证了技术体系的适用性与可行性,取得良好的应用效果。水生态保护目标制定理论和方法方面的研究探索可为全国相关工作提供参考依据。  相似文献   

12.
河南省南太行地区山水林田湖草生态保护与修复   总被引:2,自引:0,他引:2  
宇振荣  杨新民  陈雅杰 《生态学报》2019,39(23):8886-8895
综合景观管理是基于可持续土地管理(SLM)、可持续林业管理(SFM)和水资源综合管理(IWRM)提出的生态保护和修复方法,强调区域整体性、系统性和多功能性。《河南省南太行地区山水林田湖草生态保护与修复工程实施方案》还在规划设计阶段,概括分析了《河南省南太行地区山水林田湖草生态保护与修复工程实施方案》中提出的区域生态环境条件、问题、总体思路和目标、总体布局和生态功能分区、主要任务和工程等,并提出管控、修山、治水、护渠、复绿、整地、扩湿等综合性生态修复策略,实施矿山环境治理、流域水环境生态修复、生态系统保护、土地整治与污染生态修复、重要生态系统保育与生物多样性维护、科技创新工程,体现系统性和整体性。在此基础上,文章提出应加强综合景观管理,主要包括开展基于“生命共同体”的系统规划设计,加强“生命共同体”景观特征和生态过程研究,提升实施项目的多功能性,加强工程技术集成应用和研发,加强公众参与与合作等建议。  相似文献   

13.
Monitoring changes in population levels of a wide range of species in biodiversity research and conservation requires practical, easy-to-use and efficient assessment and monitoring methods. Dragonflies (Insecta: Odonata) are a valuable tool for assessing aquatic systems and have been used as indicators of ecological health, ecological integrity, and environmental change, including climatic change, as well as indicators of habitat recovery. We field-tested a freshwater ecological integrity index, the Dragonfly Biotic Index (DBI), based on dragonfly assemblages at the local scale, and compared the DBI to a biodiversity index (average taxonomic distinctness, AvTD) as well as to a standard freshwater benthic macroinvertebrate-based freshwater health index (South African Scoring System, using Average Score Per Taxon, ASPT). We sampled 20 river sites, selected a priori. Adult dragonflies and benthic macroinvertebrates were collected using standardized methods. Environmental variables were collected in situ, and water samples taken. Temperature and pH were the most important physical environmental variables in explaining the assemblage structure, and we found significant abiotic–biotic relationships, as well as biotic–biotic relationships. Overall, dragonflies were more sensitive to changes in river condition than were macroinvertebrates, in part because they were responding at the species rather than higher taxonomic level. AvTD scores did not show any significant relationship with changes in river condition. Furthermore, sites with low biotic scores (indicating disturbance) had high AvTD values. In contrast, DBI site value and ASPT scores were highly significantly correlated. We conclude that dragonfly assemblages in the form of a DBI are an excellent tool for environmental assessment and monitoring freshwater biodiversity, with the potential to replace labour-intensive benthic macroinvertebrate-based freshwater quality assessments, such as SASS.  相似文献   

14.
Until recently, the general biodiversity concepts have suggested common patterns of species richness dynamics for both small planktonic and large benthic organisms in the gradients of environmental factors, including salinity, which is the major abiotic characteristic that influences the diversity of flora and fauna in coastal marine ecosystems. Recent studies discovered an extremely species-rich aquatic microworld and resulted in proposing new concepts and shifting the paradigms in biodiversity studies, including those on planktonic unicellular eukaryotes such as protists. As a result, Remane’s species-minimum concept has been revisited and the range of its application updated. This paper provides a review of the studies dedicated to establishing, developing, and analyzing the novel protistan species-maximum concept for the critical salinity zone (5–8‰), or the horohalinicum. The obtained new data contribute to the formation of the modern views on aquatic ecosystem dynamics, biodiversity conservation, and effective ecological management aimed at maintaining the environmental balance and the rational use of marine biological resources.  相似文献   

15.
郑晓明  杨庆文 《生物多样性》2021,29(2):167-1156
农业生物多样性是农业安全生产的基础条件和农业可持续发展的战略资源。中国自20世纪50年代就开始重视农业生物多样性的保护, 建立了较为完善的法律法规等保障体系, 并在农业生态系统、物种和遗传多样性3个层面采取了一系列保护措施, 基本形成了异位保存和原生境保护相互补充的保护体系, 取得了显著的保护成效。本文概述了中国近70年来农业生物多样性保护在法律法规和保护机制、保护规划、保护体系和能力建设方面取得的进展, 指出我国农业生物多样性保护面临着未与国际国内发展战略相适应、保护体系不完整、保护能力不足等问题, 并提出完善我国农业生物多样性保护体系、促进农业生态系统服务功能系统化、加快农业生物多样性主流化进程以及加强能力建设等相关建议。  相似文献   

16.
Summary About one third of the Dutch environmental research is concentrated on aquatic problems. The largest number of these projects is physicochemical (65%) and 47% of the aquatic projects contains an ecological component. The aquatic research projects are executed in a large number of different research institutes. Many institutes just formulated one project (43.2%) and about 10% of the institutes formulated 10 projects. The institutes with 10 or more projects account for almost 50% of the total number of projects. However, the size of the research projects with respect to the average total personnel per year may differ considerably. The largest number of aquatic research projects is carried out in governmental institutes. This relative high share of governmental institutes has proportionally increased during the period of 1975–1982. During this period the relative shares of all the aquatic research projects with an ecological component, of the strictly ecological projects and of the ecological/physicochemical projects have also proportionally inclined. However, in absolute numbers there seems to be a decline of both ecological and non-ecological projects on aquatic problems.  相似文献   

17.
自然保护地是维护国家生态安全, 提升生物多样性保护成效的重要载体, 对保护地生态系统进行实时、高频、多尺度的监测是认知其动态变化的有效手段, 也是实现自然保护地生态系统健康管理的基石。由于目前我国没有形成自然保护地生态系统监测网络, 缺少统一的联网监测指标体系, 导致多数自然保护地生态系统组成家底不清、动态不明, 应对生物多样性保护新问题的能力不足, 并且在国家尺度上的自然保护地生态系统健康状况及保护成效评估缺乏联网监测数据支撑。因此, 亟需构建国家尺度的自然保护地生态系统组成和动态监测网络, 以及一套科学、系统、规范的自然保护地生态系统联网监测指标体系。该文针对自然保护地生物多样性和生态系统监测的目标和内容, 参考国内外现有的生态系统监测网络的指标体系, 确定了自然保护地生态系统联网监测指标体系建立和选取的基本原则, 建立了一套适用于国家尺度的自然保护地生态系统联网监测指标体系, 并在6个国家级自然保护区进行示范。构建的指标体系针对构成生态系统的6类关键要素(生境要素、生物要素、气象要素、土壤要素、大气和水环境要素、景观要素)制定了30个监测指标, 有效应用于森林、草地、荒漠、湿地等生态系统类型的自然保护地, 能够实现对不同类型自然保护地生态系统组分和结构的现状和演变特征进行长期、动态化监测, 并可为自然保护地保护成效评估和健康管理提供规范化、标准化的基础数据。  相似文献   

18.
Freshwater ecosystems support biological communities with high species richness and conservation interest. However, these ecosystems are highly altered by human intervention and threatened worldwide, making them a priority in conservation planning and biodiversity monitoring. Bryophytes, including several conservation-interest taxa, are recognized indicators of ecological status in freshwaters. We aimed to develop a framework for designing monitoring networks to detect trends in aquatic and semi-aquatic bryophyte communities, prioritizing high-conservation interest communities in different contexts of human pressure (specifically, resulting from the intersection of two criteria: (i) protection status and (ii) presence of a potential impact area).The framework consists of three steps: (1) Spatial modelling of biodiversity; (2) Spatial conservation prioritization; and (3) Model-assisted monitoring network design. Community-level modelling was used to model the distribution of the main bryophyte assemblages in the study area. A conservation prioritization software was utilized to identify areas with high conservation value. The monitoring network was designed using stratified random sampling and unequal-probability sampling techniques to target high conservation value sites distributed across different contexts of human pressure.We have identified four distinct community types, each characterized both by a small group of common and dominant species, and by small group of rarer, conservation-interest species. This typification of four species assemblages occurring in the study area, also highlighted those with potentially higher conservation-interest. The most valuable areas for the conservation of aquatic and semi-aquatic bryophyte communities coincide with specific environmental zones: mountainous areas in Lusitania, large watercourses in the Mediterranean North and some locations in the Mediterranean Mountains. Finally, we obtained a potential monitoring network consisting of 64 monitoring points, unequally distributed across different contexts of human pressure, privileging locations with higher conservation value.The framework presented here illustrates the potential of combining biodiversity modelling, spatial conservation prioritization and monitoring design in the development of monitoring networks. Namely, this framework allowed us to counter data deficiencies, to identify high priority areas to monitor and to design a monitoring network considering different scenarios of human pressure at a regional scale.This framework can also be valuable for conservation efforts as an approach to monitoring conservation-interest biodiversity features in anthropogenically modified riverscapes, which present different degrees of human pressure and the cumulative effects of these different impact elements. Moreover, this approach allows for the comprehensive monitoring of biodiversity values important for management at the national and regional levels. In addition, this framework is one of the first efforts in the development of monitoring networks that target aquatic and semi-aquatic bryophyte communities, a long-neglected plant group of high ecological and conservation importance in freshwater ecosystems.  相似文献   

19.
Freshwater ecosystems face multiple threats to their stability globally. Poyang Lake is the largest lake in China, but its habitat has been seriously degraded because of human activities and natural factors (e.g. climate change), resulting in a decline in freshwater biodiversity. Zooplankton are useful indicators of environmental stressors because they are sensitive to external perturbations. DNA metabarcoding is an approach that has gained significant traction by aiding ecosystem conservation and management. Here, the seasonal and spatial variability in the zooplankton diversity were analyzed in the Poyang Lake Basin using DNA metabarcoding. The results showed that the community structure of zooplankton exhibited significant seasonal and spatial variability using DNA metabarcoding, where the community structure was correlated with turbidity, water temperature, pH, total phosphorus, and chlorophyll‐a. These results indicated habitat variations affected by human activities and seasonal change could be the main driving factors for the variations of zooplankton community. This study also provides an important reference for the management of aquatic ecosystem health and conservation of aquatic biodiversity.  相似文献   

20.
为解决过去保护修复工程只考虑单要素、单一类型生态系统的问题,我国于2016年开展了“山水林田湖草”生态修复工程,旨在通过整体、系统、综合的方法对各类生态系统进行统筹治理。然而,目前的工程治理中仍然存在对系统内部及系统间耦合概念理解不充分、系统耦合机制不明晰、对“尺度”的关注不足、缺少科学的分析方法等问题,制约了保护修复的成效。对此,首先将多个尺度下的耦合研究方法进行归纳总结,并以国家重点冰川水源涵养区及生物多样性保护优先区——疏勒河流域为例,将耦合方法用于分析要素间、自然生态系统间的耦合关系,最后基于该实例研究,提出多尺度耦合分析框架与“升尺度”保护修复模式,以期帮助相关决策者明晰“山水工程”中要素、系统间的耦合关系,增强治理的科学性与有效性,进而推进我国社会与环境的可持续发展。  相似文献   

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