21世纪土壤科学展望   总被引：28，自引：0，他引：28  

赵其国 《地球科学进展》2001,16(5):704-709

土壤学是解决人口－资源－环境－粮食矛盾的重要学科之一。在21世纪，从圈层角度研究土壤圈物质的组成、性质及能量循环及其对人类生存和环境的影响是土壤学发展的总趋势，其中全球土壤变化是土壤学研究的战略重点，数字化与信息化是土壤学发展的驱动力，土壤质量与环境是土壤学的重要内容，保护土壤资源、提高土壤肥力是土壤学的重要任务，研究资源节约型高效持续农业是土壤学的历史使命，加强土壤学基础理论研究是土壤学发展的基石。  相似文献   

中国湿地科学的进展与展望   总被引：121，自引：3，他引：121  

孙广友 《地球科学进展》2000,15(6):666-672

湿地学在国际上尚未形成完整的理论体系。在中国则处于初创时期,与国际水平差距较大。全面总结了中国湿地50年的主要成就:完成了全国沼泽调查;建成了若干研究基地,取得了一大批研究成果。在湿地生态系统及湿地与全球变化、湿地分类等方面的研究开始进入国际前沿。在此基础上提出8项未来研究与建设重点:湿地区域分异规律、湿地形成的多层圈作用过程与机制、湿地沉积动力学、内陆盐碱湿地与西部开发、湿地环境重建、湿地可持续发展、湿地保护理论与法规、建设数字湿地系统。  相似文献   

1998年南极中山站海洋气溶胶的化学组成及其来源判别   总被引：6，自引：0，他引：6  

黄自强  暨卫东  杨绪林  黄荣坦  汤荣坤  于涛  张功勋 《海洋学报》2005,27(3):59-66

从1998年3月7日至1999年3月2日历时12个月,在南极中山站连续采集52个海洋气溶胶样品,提供全部样品的13种化学元素铜、铅、锌、镉、铁、铝、锰、铬、钒、钾、钠、钙、镁含量的实测值.研究表明中山站气溶胶化学成分的含量具有季节性变化的特征.通过富集因子、相关分析、因子分析等方法判别中山站气溶胶化学成分的来源.  相似文献   

论提高青岛海岸工程地震安全性   总被引：1，自引：0，他引：1  

徐青  张义正 《海岸工程》2003,22(4):23-27

综合提高青岛海岸工程地震安全性，不仅是一项综合科技攻关项目，也是一项系统工程的建设，它对于持续发展青岛经济至关重要。现对青岛海岸工程地震安全性的现状及应采取措施进行了初步讨论。  相似文献   

Physical and biological characteristics of the pelagic system across Fram Strait to Kongsfjorden   总被引：1，自引：1，他引：1  

Haakon Hop  Stig Falk-Petersen  Harald Svendsen  Slawek Kwasniewski  Vladimir Pavlov  Olga Pavlova  Janne E. Sreide 《Progress in Oceanography》2006,71(2-4):182

The Fram Strait is very important with regard to heat and mass exchange in the Arctic Ocean, and the large quantities of heat carried north by the West Spitsbergen Current (WSC) influence the climate in the Arctic region as a whole. A large volume of water and ice is transported through Fram Strait, with net water transport of 1.7–3.2 Sv southward in the East Greenland Current and a volume ice flux in the range of 0.06–0.11 Sv. The mean annual ice flux is about 866,000 km² yr⁻¹. The Kongsfjorden–Krossfjorden fjord system on the coast of Spitsbergen, or at the eastern extreme of Fram Strait, is mainly affected by the northbound transport of water in the WSC. Mixing processes on the shelf result in Transformed Atlantic Water in the fjords, and the advection of Atlantic water also carries boreal fauna into the fjords. The phytoplankton production is about 80 g C m⁻² yr⁻¹ in Fram Strait, and has been estimated both below and above this for Kongsfjorden. The zooplankton fauna is diverse, but dominated in terms of biomass by calanoid copepods, particularly Calanus glacialis and C. finmarchicus. Other important copepods include C. hyperboreus, Metridia longa and the smaller, more numerous Pseudocalanus (P. minutus and P. acuspes), Microcalanus (M. pusillus and M. pygmaeus) and Oithona similis. The most important species of other taxa appear to be the amphipods Themisto libellula and T. abyssorum, the euphausiids Thysanoessa inermis and T. longicaudata and the chaetognaths Sagitta elegans and Eukrohnia hamata. A comparison between the open ocean of Fram Strait and the restricted fjord system of Kongsfjorden–Krossfjorden can be made within limitations. The same species tend to dominate, but the Fram Strait zooplankton fauna differs by the presence of meso- and bathypelagic copepods. The seasonal and inter-annual variation in zooplankton is described for Kongsfjorden based on the record during July 1996–2002. The ice macrofauna is much less diverse, consisting of a handful of amphipod species and the polar cod. The ice-associated biomass transport of ice-amphipods was calculated, based on the ice area transport, at about 3.55 × 10⁶ ton wet weight per year or about 4.2 × 10⁵ t C yr⁻¹. This represents a large energy input to the Greenland Sea, but also a drain on the core population residing in the multi-year pack ice (MYI) in the Arctic Ocean. A continuous habitat loss of MYI due to climate warming will likely reduce dramatically the sympagic food source. The pelagic and sympagic food web structures were revealed by stable isotopes. The carbon sources of particulate organic matter (POM), being Ice-POM and Pelagic-POM, revealed different isotopic signals in the organisms of the food web, and also provided information about the sympagic–pelagic and pelagic–benthic couplings. The marine food web and energy pathways were further determined by fatty acid trophic markers, which to a large extent supported the stable isotope picture of the marine food web, although some discrepancies were noted, particularly with regard to predator–prey relationships of ctenophores and pteropods.  相似文献   

Policy and knowledge in fisheries management: a policy brief   总被引：1，自引：3，他引：1  

Schwach  Vera; Bailly  Denis; Christensen  Anne-Sofie; Delaney  Alyne E.; Degnbol  Poul; van Densen  Wim L. T.; Holm  Petter; McLay  H. Anne; Nielsen  Kare Nolde; Pastoors  Martin A.; Reeves  Stuart A.; Wilson  Douglas C. 《ICES Journal of Marine Science》2007,64(4):798-803

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Climate, fishery and society interactions: Observations from the North Atlantic     

Lawrence C. Hamilton   《Deep Sea Research Part II: Topical Studies in Oceanography》2007,54(23-26):2958

Interdisciplinary studies comparing fisheries-dependent regions across the North Atlantic find a number of broad patterns. Large ecological shifts, disastrous to historical fisheries, have resulted when unfavorable climatic events occur atop overfishing. The “teleconnections” linking fisheries crises across long distances include human technology and markets, as well as climate or migratory fish species. Overfishing and climate-driven changes have led to a shift downwards in trophic levels of fisheries takes in some ecosystems, from dominance by bony fish to crustaceans. Fishing societies adapt to new ecological conditions through social reorganization that have benefited some people and places, while leaving others behind. Characteristic patterns of demographic change are among the symptoms of such reorganization. These general observations emerge from a review of recent case studies of individual fishing communities, such as those conducted for the North Atlantic Arc research project.  相似文献   

ODP与中国固体地球科学     

李乃胜 《海洋科学》1996,20(3):3-14

国际大洋钻探计划自１９８３年以来，已成功地实施了６６个航次的深海钻探作业，获取钻探岩芯逾１０００００ｍ。在关于大陆边缘的构造演化，海洋地壳的形成与发展，地壳流体循环和壳幔相互作用海洋沉积结构和古海洋学，地球大气圈、水圈、冰圈、生物圈的长期变化等众多研究领域取得了一系列重大科研成果。  相似文献   

Gaia理论与地球系统科学     

孙枢  王成善 《地质学报》2008,82(1):1-8

本文简要介绍了Gaia理论的提出背景、科学内涵,及其最初验证模型———雏菊世界。Gaia理论将地球与生物当作一个可以自我调节的整体,强调生物圈对全球环境的调节作用。在此基础上,文章着重分析Gaia理论在全球变化、地质事件、生物进化研究中的应用,指出在进行地球系统科学研究过程中,应以Gaia理论为指导,不能把生物仅仅作为环境的附属产品,而片面强调环境对生物进化的制约。同时也要认清生物在自身进化的同时,也积极地调节着全球环境,使之更有利于生物进化。生物圈是地球具有生命的直观体现,同时也是联系地球各圈层的关键环节。正确认识生物圈对于全球环境演化的调节作用,不仅帮助我们认识地球系统的全貌,更可以推动地学研究深入发展,对全面研究全球变化有积极意义。Gaia理论正处于发展期,理论需要进一步发展与完善,在实际应用中,应该对现有的学科进行更为广泛的综合。我国地学工作者应该抓住这一科学方向,为地球系统科学理论做出应有的贡献。  相似文献   

伊通火山群地质遗迹的科考与旅游价值     

孟涛  邢立新  潘军  刘祥 《吉林地质》2008,27(3)

伊通火山群是以新生代火山地质环境为主形成的自然形态、自然环境系统,在火山地质构造、成因机制、典型岩石露头、地形地貌等方面有其自己的特色。因特殊的火山成因机制被火山学者命名为"伊通型"火山,所在区域列为国家级自然保护区和省级地质公园。伊通火山群地质遗迹具有火山地质科学研究的典型性和科学性、可供游人欣赏和休憩的自然性与观赏性。  相似文献