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1.
Seasonal change in body length of important small copepods and relationship with environmental factors in Jiaozhou Bay,China 总被引：1，自引：0，他引：1
Differences among species in prosome length and in species’ response to environmental factors do exist. Therefore, it is useful to examine prosome length for different copepod species in variable environments. Seasonal variations in prosome length of four small copepods and their copepodite stages in the Jiaozhou Bay were compared and the relative influence of temperature, salinity, and chlorophyll concentration were examined. Two peaks were found in the mean prosome length of Paracalanus parvus (in early winter and May). For Acartia bifilosa, the maximum values of all copepodites occurred mainly from February to April, and decreased to the bottom in July. Prosome length of Acartia pacifica peaked when it first appeared in June, then reached to the minimum in July. Parvocalanus crassirostris only appeared from late summer to autumn and the mean prosome length showed no clear changes. Correlations of adult prosome length with environmental factors were evaluated. For the four species, temperature was negatively correlated to prosome length except for P. crassirostris. But the different species varied markedly in their responds to temperature. A. bifilosa showed a more definite trend of size variation with temperature than P. parvus and A. pacifica. Correlations of prosome length with salinity were significantly positive for almost all the small copepods. The relationship between chlorophyll concentration and prosome length was complicated for these copepods, but for P. parvus, chlorophyll concentration was also an important affecting factor. Furthermore, investigation needs to be done on food quality for some copepod. These results are essential to estimate the biomass and the production, and to understand these small copepods’ population dynamics in this human-affected bay. 相似文献
2.
Acartia bifilosa (Copepoda: Calanoida) is a common species in offing of global waters and it often becomes dominant species in some estuaries. This species develops different strategy according to variation of environment. Despite its ecological role, Acartia bifilosa also has been concerned as live feeds in aquaculture, but study on egg production rate of this species in saturated diet in different temperature and different diet is so far not available. In order to interpret the importance of temperature and diet on natural population variation and also on aquaculture as foods of larval fish, the functional response of reproductive success of Acartia bifilosa was quantified in the laboratory using different temperatures and diets.
Acartia bifilosa was captured in Jiaozhou Bay and acclimated to corresponding temperature for 3~4 days. In order to reduce the effect of large extent temperature range on organism, we captured Acartia bifilosa from March to June and acclimated them to temperature which is adjacent to natural temperature. Daily egg production rate (EPR, eggs female-1day-1) was detected for 11~15 days at 5 different temperatures ranged from 8.0 to 23 °C and all the females was feed on saturated diet all through the experiments. EPR on first day was not calculated in the mean EPR to eliminate the effect of different diets. This result showed that Acartia bifilosa spawned continuously during the experiment days and no obvious regulation was found. EPR was positively correlated with temperature from 8.0 to 23 °C. The highest mean EPR was observed at 23 °C (7.3 eggs female-1day-1), and the lowest value was found at 8 °C (3.8 eggs female-1day-1). The effect of diets on EPR was evaluated at two different temperatures (8.0 °C and 12.5 °C). Same trends were found at the two temperatures: mean EPR fed on Chaetoceros sp. was higher than that fed on Skeletonema costatum, and during the 14-day experiments, EPR was higher for females fed on Skeletonema costatum than chaetoceros sp. in the first few days (3~5 days), but it changed reversely in the subsequent days until the end of the experiments. Hatched eggs were observed in the two experiments at temperature 8°C and 12.5 °C and no diapause eggs were found. The hatching success rate was low at 8°C but reached 93.2% at 12.5 °C.
According to the results in this paper, we detected the comfortable temperature range for EPR, and evaluated the effect of Skeletonema costatum which often brings out red tide in natural waters. These results are beneficial to ecological research for explaining population variation and population recruitment of this species, These data also can be used in Acartia bifilosa aquaculture. 相似文献
3.
期刊评价指标能定量评价期刊的相互影响和相互作用,正确评估期刊在科学交流体系中的作用和地位.本文基于2006—2019年版《中国科技期刊引证报告(核心版)》收录的统计数据,选取了《地球学报》期刊被引用计量指标(核心总被引频次、核心影响因子)、期刊来源计量指标(来源文献量、平均引文数、基金论文比)、学科分类内期刊计量指标(综合评价总分、学科扩散指数、学科影响指标),分析了其变化趋势,结论如下:核心总被引频次、平均引文数、学科扩散指数、学科影响指标显著提高;核心影响因子和综合评价总分波动式上升;来源文献量、基金论文比基本保持稳定.上述研究表明,《地球学报》学术质量和影响力不断提升,科学交流程度和吸收外部信息能力显著增强,这与其近年来实施的一系列影响力提升措施密切相关,如注重文章质量和原始创新性,树立精品意识;辟特色栏目,推优秀专辑;独特的封面设计理念及"封面故事";注重编辑与出版质量;关注出版行业和期刊发展动态等. 相似文献
4.
《地球学报》成为EI来源期刊的体会 总被引：1，自引：0，他引：1
《地球学报》虽然没有向EI机构提出过收录申请, 但2013年成为了EI来源期刊。本文通过介绍EI数据库收录期刊的原则和标准, 分析了《地球学报》成为EI来源期刊的优势和必备条件: ①注重期刊特色, 有独特的封面设计理念及“封面故事”特色。②展示地球科学各分支学科具有创新性的成果, 其中包括矿业、煤炭、石油等研究领域的论文; ③执行国际标准, 重视国际化和标准化; ④重视英文, 重要信息中英文对照; ⑤注重论文学术质量和原始创新性, 积极约稿和组稿; ⑥已被多家国外著名数据库收录; ⑦美国ISI Web of Knowledge引文期刊; ⑧编委国际化; ⑨注重编辑质量和服务意识; ⑩关注出版行业动态和期刊发展状况。 相似文献
5.
海岸带蓝碳广义上指盐沼湿地、红树林和海草床等海岸带高等植物以及浮游植物、藻类和贝类生物等,在自身生长和微生物的共同作用下,将大气中的CO_2吸收、转化并长期保存到海岸带底泥中的这部分碳,以及其中一部分从海岸带向近海及大洋输出的有机碳.海岸带蓝碳单位面积的固碳能力远大于陆地碳库.盐沼湿地、红树林、海草床、渔业碳汇和微型生物碳泵等5类海岸带碳汇需要进一步研究其固碳机理和调控因子.海岸带蓝碳的定量研究方法包括碳收支的监测、模拟实验和模型研究.我们可以通过恢复、保护和增加这些碳汇来获取新增碳汇,从而得到碳积分,进而通过市场机制推动生态保护和恢复.针对全球应对气候变化的迫切需求以及中国固碳减排的承诺,我们应加强海岸带蓝碳的科学和政策研究.利用蓝碳原理,保护和恢复盐沼湿地、红树林、海草床,增进微型生物碳泵的储碳功能,并建设可持续性海洋牧场等重要海岸带生态系统. 相似文献
6.
Seasonal variation in community structure and body length of dominant copepods around artificial reefs in Xiaoshi Island, China 总被引：2，自引：0，他引：2
This study aims to investigate the seasonal variations in copepod community structure and prosome length of dominant species from March 2009 to January 2010 around artificial reefs in Xiaoshi Island,Yellow Sea,Weihai,China.Samples were collected using two types of plankton net(Model I and Model II) for different-sized copepods.The number of taxon was calculated from the data of both the net types,while the copepod abundance was done using the samples from Model II only.Sixteen species of planktonic copepods,including 5 dominant species,were recorded.Results reveal that Oithona similis was the first dominant species from March to June,and was replaced by Paracalanus parvus in September;both dominated the copepod community in January.Acartia hongi was the second dominant species from March to September.Centropages abdominalis was the third dominant species from March to June,and was replaced by O.similis in September and Corycaeus affinis in January.C.affinis was the fourth dominant species in September.Population density of the dominant copepods was compared with that of other similar regions.We found that the dominant species were mostly small copepods(<1 mm) except for adult Centrapages abdominalis.Seasonal variation in prosome length of O.similis,C.abdominalis,and C.affinis,and their copepodites were studied for the first time in China.For P.parvus and A.hongi,seasonal trends in prosome length variation were similar with those in Jiaozhou Bay,Yellow Sea,Qingdao,China,in a similar temperate domain.The results are helpful for future calculation of copepod biomass and production,and for investigation of the relationship between copepods and fish resources. 相似文献
7.
在数字出版时代,网络首发能显著提升我国科技期刊质量和学术影响力。本研究以《地球学报》为例,统计其从2018年第3期至2022年第3期共318篇文章的投稿日期、改回日期、网络首发日期、刊发日期、被引频次、首次被引日期、印刷版下载量、网络首发版下载量等。对其出版周期、质量控制、出版方式、被引和下载量、主要期刊评价指标等进行分析。分析表明,网络首发能大幅缩短论文出版周期,吸引优秀稿源;避免了论文的政治性差错,学术和出版质量都得到了显著提升;增强出版助力学术期刊的知识生产与传播;网络首发出版流程和增强出版能有效避免学术不端行为;提高了论文的被引频次和下载量。网络首发对推动我国科技期刊的高质量发展,提升其质量和学术具有积极作用。 相似文献
8.
今年3月14日公布施行并生效的<宪法>修正案,将原<宪法>第十条第三款"国家为了公共利益的需要,可以依照法律规定对土地实行征用",修改为:"国家为了公共利益的需要,可以依照法律规定对土地实行征收或者征用并给予补偿".相应的<中华人民共和国土地管理法>以及配套的土地法规也应在此基础上作进一步的修改. 相似文献
9.
地下水专业档案管理的几点思考 总被引：3，自引：0，他引：3
地下水专业档案是地下水工作者在进行地下水管理和地下水监测活动中积累的宝贵财富,是进行地下水管理和水利建设重要的参考依据,随着我国地下水资源管理的深入开展,地下水档案在此领域内所起的作用日益明显,同时在国民经济建设中也发挥着不可替代的重要作用.通过多年地下水专业档案管理的实践,从地下水专业档案的管理和利用的角度,对其内容、重要性、存在问题、管理方法等多方面做了阐述与探讨. 相似文献
10.
近年来《地球学报》影响力逐步提升。继2013年成为EI来源期刊后,2012—2014连续三年被评为"中国最具国际影响力学术期刊";2015年被评为"中国权威学术期刊(RCCSE)";荣获2015年度科学出版社"期刊出版质量优秀奖"。作为中文地学类学术期刊,本文总结了《地球学报》提升影响力的一些做法和经验:1注重文章学术质量和原始创新性,树立精品意识;2辟特色栏目,推优秀专辑;3具有独特的封面设计理念及"封面故事"特色;4重视英文,重要信息中英文对照,最大限度的将文章内容展示给国际读者;5注重编辑与出版质量;6关注出版行业和期刊发展动态,与时俱进。 相似文献