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961.
The family Mesopsychidae Tillyard,1917 presently consists of ten described genera from the Early Permian to the Early Cretaceous of Australia,China,Kyrgyzstan,Russia,South Africa,Tajikistan,and Ukraine.Herein,a new genus and a new species of fossil mesopsychid,Epicharmesopsyche pentavenulosa gen.et sp.nov.,is described from the Middle Jurassic Jiulongshan Formation of Inner Mongolia,China,supplementing the family-level diversity.The well-preserved,new material reveals many characters,including antennae,wing venation,shape and genitalia that increase our morphological understanding of the family,although unfortunately the mouthparts and most of the legs are not preserved.Diagnosis of the Mesopsychidae is emended to include a four-or five-branched MP in both the fore-and hind wings.This is the first documentation of a wing coupling structure in the Mesopsychidae,consisting of three to four frenula bristles on the humeral lobe at the base of the costal margin of both hind wings.Asymmetrical shape and size of the left and right wings on a specimen of E.pentavenulosa gen.et sp.nov.,seems to be a common condition for mesopsychid taxa from northeastern China. 相似文献
962.
香港牡蛎(Crassostrea hongkongensis)与长牡蛎(Crassostrea gigas)种间杂种遗传力评估 总被引:1,自引:1,他引:0
以平衡巢式设计(1长牡蛎♂:3香港牡蛎♀)构建的45个香港牡蛎(Crassostrea hongkongensis)×长牡蛎(Crassostrea gigas)种间杂交家系为材料,对其生长、存活及产量性状狭义遗传力进行了评估,并对其两两对应性状表型相关及遗传相关进行了分析。结果表明:(1)生长性状的遗传力大小为0.6207—0.8785,以父系半同胞组内相关法估计的幼虫15日龄、稚贝180日龄、幼贝360日龄壳高遗传力分别为0.6355、0.4828、0.5787,其360日龄鲜重遗传力为0.7740;(2)存活性状的遗传力大小为0.2748—0.3957,以父系半同胞组内相关法估计的幼虫15日龄、稚贝180日龄、幼贝360日龄存活率遗传力分别为0.1900、0.2939、0.4064;(3)产量是生长与存活的共同作用结果,360日龄产量的遗传力及以父系半同胞组内相关法估计的遗传力分别为0.6706、0.5018。从其生长相关性上看,幼虫期与稚贝期出现了微弱负向相关;除了幼虫期与幼贝期的壳高及产量,及其稚贝期与幼贝产量间无相关性以外;其它的两两生长性状间均为显著正相关。从存活与产量的相关性上看,无论是表型性状,还是遗传性状均出现了积极的正相关,以遗传相关为主。本研究为建立远缘杂交育种方法和策略提供必要的理论依据。 相似文献
963.
东海南部海域头足类群落结构特征及其与环境关系 总被引:7,自引:0,他引:7
根据2008年春(5月)、夏(8月)、秋(11月)、冬(2009年2月)四季东海区桁杆拖虾网调查期间所采集的头足类资料,分析了东海南部海域头足类种类组成及优势种,采用生态多样性指数分析了群落物种多样性,并运用典范对应分析法研究了头足类群落变化与主要环境因子的关系。结果表明:东海南部海域共捕获头足类22种,隶属于3目6科8属,优势种主要有神户乌贼(Sepia kobiensis)、双喙耳乌贼(Sepiola birostrata)、短蛸(Octopus ocellutus)和杜氏枪乌贼(Loligo duvaucelii)等;种类丰富度指数D变化范围为0—1.30,多样性指数H′变化范围为0—1.69,均匀度指数J变化范围为0.02—1.00,t检验表明,各群落多样性指数四季之间的差异均不显著(P0.05);根据典范对应分析认为,底层水温为影响调查海域头足类种类组成的主要环境因子。 相似文献
964.
965.
《Marine Policy》2014
This paper examines the potential relationships between the ecosystem services provided by the coastal and marine environment and the designation of marine protected areas. The hypothesis is that relationships exist between the provision of ecosystem services and the features protected by marine protected areas. It is considered that protection will maintain these features in good ecological condition and in some cases will restore ecological functioning with positive effects on the delivery of ecosystem services, as pressures upon the protected features are reduced. As the number of marine protected area designations grows, system-wide effects to communities from improvements in delivery of a range of ecosystem services may be realised. This paper provides a comparative analysis of the jurisdictional marine protected area policies proposed by the English, Welsh and Scottish Governments. It presents structured assessment matrices developed from the literature and expert opinion, of ecosystem service provision by marine protected habitats and species and applies the findings to a range of existing UK marine protected areas to demonstrate its relevance. The approach and case study findings are discussed within the wider context of marine ecosystem services and marine protected area management. 相似文献
966.
《Marine Policy》2014
The main objective of recent international legislative measures and policies concerning marine ecosystems is to ensure sustainable environmental management to maintain a good status for marine waters, habitats and resources, with the ultimate target of achieving an integrated ecosystem-based approach to management. Because bioinvasions pose significant threats to marine ecosystems and the goods and services these provide, non-indigenous species (NIS) are included in the more recent legislative documents. A major challenge for the scientific community is to translate the principles of the legislative directives into a realistic, integrated ecosystem-based approach and at the same time provide stakeholders with best practices for managing NIS. The aim of this paper, prepared by members of the Working Group on Introductions and Transfers of Marine Organisms (WGITMO) of the International Council for the Exploration of the Sea (ICES), is to provide guidance for the application of NIS related management in the European Union Marine Strategy Framework Directive (MSFD). Ten recommendations, including NIS identification, standardization of sampling and data, indicators, propagule pressure and management issues are considered in this paper. While most of these suggestions were developed to improve the implementation of the MSFD, several may be more widely applicable. 相似文献
967.
首次报道了闽东海域分布的3种石珊瑚,分别为造礁石珊瑚陀螺珊瑚(Turbinaria sp.)、非造礁石珊瑚猩红筒星珊瑚(Tubastrea coccinea Lesson)和1个珊瑚待定种,其中陀螺珊瑚和1个珊瑚待定种为中国新记录.珊瑚分布面积约3.24km2,主要呈零星斑块状分布在岛礁周围水深2—25m近岸岩礁区.2012年5~8月对闽东台山列岛和星仔列岛4km2范围内的55个岛礁近岸海域进行4个航次的调查表明,珊瑚的分布总体上南部的台山列岛海域分布数量多于北部的星仔列岛,海岛东部海域略多于西部.研究认为,闽东海域发现陀螺珊瑚说明其分布主要受台湾暖流的影响,揭示我国大陆沿岸造礁石珊瑚分布北缘可能扩展到台山列岛和星仔列岛. 相似文献
968.
全国海洋环境监测每年获得大量的生物多样性监测数据,其中生物种类名记录存在书写不规范、格式不统一、同物异名、学名和中文名缺失、拼写错误等情况,对数据的质量和使用产生很大影响.为了对这些分类数据进行质量控制,构建质控数据库.以2011、2012年全国海洋环境监测实测生物分类数据为原始分类数据,以《中国海洋物种多样性》、《海洋生物分类代码》、《中国海洋生物名录》中的物种数据为标准生物名称,采用计算机程序匹配与人工匹配相结合的方法,建立原始分类数据与标准生物名称的对应关系,完成匹配分类数据的标准化处理并入库,形成质控数据库.基于质控数据库,结合质量控制程序,使得需要进行质控的生物名数据与质控数据库中"实测中文名"或"实测学名"相匹配,返回质控数据库中的"标准中文名"、"标准学名"、"标准类群"的值以及"记录处理",并作为新增列插入到原数据中,从而实现对分类数据的一站式批量质控.基于质控数据库的生物名质控方法为生物分类数据的质量控制提供了一个简单、有效且易于推广的新方法. 相似文献
969.
We studied the effect of pH(pH 5, 6, 7 and 8) on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay(BHB), Artemia franciscana from San Francisco Bay, and A. franciscana artifi cially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were signifi cantly reduced when exposed to a culture medium at pH 5 for 18 d( P 0.05). The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order: juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6–8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidifi cation has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franciscana should be feasible at pH 7–8. 相似文献
970.
Ballast water has been a topic of concern for some time because of its potential to introduce invasive species to new habitats. To comply with the International Convention for the Control and Management of Ships' Ballast Water and Sediments, members of the International Maritime Organization (IMO) must equip their ships with on-board treatment systems to eliminate organism release with ballast water. There are many challenges associated with the implementation of this IMO guideline, one of which is the selection of species for testing the ecological impacts of the treated ballast water. In the United States, ballast water toxicity test methods have been defined by the United States Environmental Protection Agency. However, the test methods had not been finalized in China until the toxicity test methods for ballast water were established in 2008. The Chinese methods have been based on species from three trophic levels: Skeletonema costatum, Neomysis awatschensis, and Ctenogobius gymnauchen. All three species live in broad estuarine and open sea areas of China; they are sensitive to reference toxicants and acclimatize easily to different conditions. In this paper, the biological characteristics, test processes and statistical analysis methods are presented for the three species. Results indicate that the methods for evaluating these three organisms can be included in the ecological toxicity tests for treated ballast water in China. 相似文献