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81.
"现代地球磁场监测与地磁基本数据积累"项目成果介绍 总被引:1,自引:0,他引:1
"现代地球磁场监测与地磁基本数据积累"项目组 《国际地震动态》2006,(9):73-77
本文详细介绍了“现代地球磁场监测与地磁基本数据积累”项目的立项背景、目标、所开展的主要工作、取得的成果、研究成果的社会效益和对该领域研究未来工作的展望。 相似文献
82.
主要介绍了“防震减灾重点地区遥感数据库”项目的立项背景、目标、所开展的主要工作、取得的成果及研究成果的社会效益,并展望了该领域未来的研究工作。 相似文献
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额济纳荒漠绿洲草坪引种与建植初步研究 总被引:2,自引:0,他引:2
通过额济纳荒漠绿洲草坪引种与建植试验,初步筛选出越冬保存率较高的草坪草10个品种;优选出适于本区建植的草坪混播配方:草地早熟禾80%+高羊茅10%+紫羊茅10%,其播量为12~24g/m2;草坪播种以春播为主。 相似文献
86.
本文通过在晋江市规划区开展抗震防灾基础调查工作中的地下水调查工作,总结在抗震防灾规划基础调查工作中对地下水专项调查的工作方法、重点及成果介绍。 相似文献
88.
Environment-ecosystem dynamic processes of Spartina alterniflora salt-marshes along the eastern China coastlines 总被引:2,自引:0,他引:2
Shu Gao YongFen Du WenJing Xie WenHua Gao DanDan Wang XiaoDong Wu 《中国科学:地球科学(英文版)》2014,57(11):2567-2586
Spartina alterniflora is ecologically important in its original habitat; however, it has caused controversy since it was introduction into China (now it has been spreading rapidly on the Jiangsu, Shanghai, Zhejiang and Fujian coasts). The purpose of the present contribution is, on the basis of an analysis and synthesis of existing data sets, to evaluate the environmental-ecological effects of S. alterniflora, and to identify the relevant scientific problems that require further research in the future. Investigations have shown that, by reducing the near-bed shear stress associated with tidal currents, S. alterniflora can enhance the settling flux of suspended sediment and deposition rate on the tidal flats over the region. Further, field survey and analysis indicate that the S. alterniflora salt-marsh has a high primary production and provides a new type of habitat for the native benthic fauna. Some macro-, meio- and micro-fauna that used to live in the native salt-marshes have adapted to the S. alterniflora salt-marsh, forming a new ecosystem. Under the influences of a number of background factors, such as latitude variations and the coastal type, the environmental-ecological changes induced by Spartine have regional differentiations. To the north of Hangzhou Bay, with a high position of the pre-Holocene stratum base, a large width of the tidal flats, and a gentle bed slope, only a small part of the intertidal zone is occupied by the S. alterniflora salt-marsh. Here, the S. alterniflora salt-marshes mainly play a positive role in coastal protection and ecosystem functioning. In contrary, to the South of Hangzhou Bay, The pre-Holocene deposits are situated in relatively deeo waters, and the width of the tidal flats formed within coastal embayments is relatively narrow. As such, the expansion of S. alterniflora has squeezed the living space of other intertidal organisms, thus has a negative ecological effect. Therefore, the regional differentiation of the Spartina effects should be sufficiently considered in coastal development and management. Furthermore, in order to predict the future evolution of the S. alterniflora wetlands over the region, in addition to in situ monitoring and measurements, an ecosystem dynamic model should be established, taking into account the coupling of the rerrestrial and marine environmental-ecological processes. 相似文献
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The Caulerpa racemosa invasion: a critical review 总被引:1,自引:0,他引:1
Caulerpa racemosa var. cylindracea is a marine Chlorophyta introduced into the Mediterranean Sea from south-western Australia. Since 1990, it has been invading the Mediterranean Sea and the Canary Islands, raising ecological problems. Although this invasion event can be considered as one of the most serious in the history of species introduced into the Mediterranean Sea, C. racemosa has not triggered as much attention as the famous "killer alga"Caulerpa taxifolia. The aim of the present study was: (i) to summarize the current state of knowledge with regard to the distribution, the various biological and ecological characteristics of the introduced C. racemosa and its impact on the Mediterranean coastal environment; (ii) to discuss the various hypotheses regarding the explanation for its rapid and successful spread; (iii) to investigate the disparity in the treatment of C. racemosa and Caulerpa taxifolia invasions; and (iv) to outline future research needs. 相似文献