南极普里兹湾溶解态镉的分布     

孙维萍  扈传昱  韩正兵  薛斌  潘建明 《海洋通报(英文版)》2011,13(1):50-59

利用25次南极科考获得的海水样,采用原子分光光度法(AAS)测定了海水中溶解态镉的含量,研究了东南极普里兹湾不同空间与时间尺度下海水中溶解态镉的分布特征.并利用同航次相关的营养盐、叶绿素a等数据,分析了影响海水中溶解态镉分布的主要因素.研究结果显示,普里兹湾表层海水中溶解态镉的分布与叶绿素a具有良好的相关性,生物过程是...  相似文献   

Dissolved organic matter and its role in red tide succession in the East China Sea in spring     

������  ����� 《中国海洋湖沼学报》2011,29(4):795-799

Dissolved fluorescent organic matter was measured using fluorescence excitation-emission matrix spectroscopy at three temporal points during a Synechococcus bloom after diatom bloom dispersion in spring, 2007. Carbohydrate and dissolved organic carbon were also analyzed. The relationship between organic matter and red tide succession was examined. The results show that after the diatom bloom, tyrosine-like fluorescence B intensity was very high within the water column and exhibited a negative correlation wi...  相似文献   

Application of stable isotope techniques in studies of carbon and nitrogen biogeochemical cycles of ecosystem   总被引：1，自引：1，他引：0  

Zhigao Sun  Xiaojie Mou  Xinhua Li  Lingling Wang  Hongli Song  Huanhuan Jiang 《中国地理科学(英文版)》2011,21(2):129-148

Stable isotope techniques have been proved useful as tools for studying the carbon (C) and nitrogen (N) biogeochemical cycles of ecosystem. This paper firstly introduced the basic principles and the distribution characteristics of stable isotope, then reviewed the recent advances and applications of stable isotope in the C and N biogeochemical cycles of ecosystem. By applying the 13 C natural abundance technique, ecologists are able to understand the photosynthetic path and CO 2 fixation of plants, the CO 2 exchange and C balance status of ecosystem, the composition, distribution and turnover of soil organic C and the sources of organic matter in food webs, while by using the 13 C labeled technique, the effects of elevated CO 2 on the C processes of ecosystem and the sources and fate of organic matter in ecosystem can be revealed in detail. Differently, by applying the 15 N natural abundance technique, ecologists are able to analyze the biological N 2 -fixation, the N sources of ecosystem, the N transformation processes of ecosystem and the N trophic status in food webs, while by using the 15 N labeled technique, the sources, transformation and fate of N in ecosystem and the effects of N input on the ecosystem can be investigated in depth. The applications of both C and N isotope natural abundance and labeled techniques, combined with the elemental, other isotope ( 34 S) and molecular biomarker information, will be more propitious to the investigation of C and N cycle mechanisms. Finally, this paper concluded the problems existed in current researches, and put forward the perspective of stable isotope techniques in the studies on C and N biogeochemical cycles of ecosystem in the future.  相似文献   

Alkaline phosphatase activity in ornithogenic soils in polar tundra     

MA DaWei  ZHU RenBin  DING Wei  SUN JianJun  LIU YaShu  SUN LiGuang 《极地研究(英文版)》2011,22(2):92-100

  相似文献   

气候变化情景下中国陆地生态系统碳吸收功能风险评价   总被引：1，自引：0，他引：1  

石晓丽  吴绍洪  戴尔阜  赵东升  潘韬 《地理研究》2011,30(4):601-611

气候变化会对陆地生态系统的碳吸收产生影响,从而改变其碳的源汇功能.因此,评估未来气候变化下陆地生态系统碳吸收功能面临的风险,可以为中国应对气候变化措施的制定和国际碳排放谈判提供科学依据.本文采用大气-植被相互作用模型对气候变化情景下净生态系统生产力进行模拟,运用线性倾向估计方法确定碳吸收功能风险评估标准,对中国陆地生态...  相似文献   

浙江省进出口产品隐含碳的计算及其影响因素     

黄敏  沈月琴  黄水灵 《地理研究》2011,26(9)

近年来,CO2等温室气体的过多排放日益为世界各国所重视。文章对浙江省近年外贸中的CO2含量进行分析研究。内涵碳的净出口量与其占全省碳排放的比值都呈现增加的势头;两个时期的进（出）口的规模变动效果全是正向;两个时期的进（出）口结构变动效果有明显差异,2005—2008年期间,出口的结构变动效果为7 201.89×104 t,进口的结构变动效果综合后为-3 124.27×104 t;在此阶段,中间投入变动效果有明显的改善,2002—2005年进（出）口的中间投入变动效果是40.34×104 t（32.21×104 t）,2005—2008年阶段是-3 428.33×104 t（-4 942.21×104 t）;单位GDP碳排放量变动效果也有明显改善,并且两个时期单位GDP碳排放量变动效果主要是由单位GDP能耗变动效果所决定;两个时期进（出）口单位能耗的碳排放量变动效果均非常小。  相似文献   

Spatial and temporal variations in C₃ and C₄ plant abundance over the Chinese Loess Plateau since the last glacial maximum     

Z. Yao  H. WuM. Liang  X. Shi 《Journal of Arid Environments》2011,75(10):881-889

Stable carbon isotopes of soil organic matter from 12 sites in the southern Chinese Loess Plateau are reviewed to examine spatial and temporal patterns of C₃ and C₄ plants in the arid to semiarid monsoonal region during three key periods - last glacial maximum, mid-Holocene, and modern. We have tentatively corrected the effects of atmospheric CO₂ concentrations and precipitation amounts on the δ¹³C endmembers for C₃ plants to reconstruct the relative proportion of C₄ plants because the δ¹³C values of C₃ plants are variable under different CO₂ and climate conditions. The results indicate that C₄ grasses increase from northwest to southeast spatially, which is consistent with present-day increasing precipitation and temperature patterns. This suggests that for a monsoon-dominant arid to semiarid region, such as the Loess Plateau, warm-season rainfall is a primary factor limiting C₄ plants growth, and thus C₄ grasses have been outcompeted by C₃ grasses/shrubs under cold-dry climate conditions. However, temporal fluctuations in atmospheric CO₂ concentration may also affect plant growth through altering water-use efficiency (WUE). Enhanced drought caused by decreased WUE due to low atmospheric CO₂ concentrations during glacial periods, combined with a cold-dry climate, leads to a decline in C₄ grasses, canceling out any advantages gained from lowered atmospheric CO₂ concentrations. To reconstruct accurately the abundance of C₃ and C₄ plants in an ecosystem and explore their controlling factors, process-based vegetation models integrating CO₂ and climatic parameters interactive with plant physiology are necessary.  相似文献   

土壤碳循环研究进展及干旱区土壤碳循环研究展望   总被引：5，自引：1，他引：4  

许文强  陈曦  罗格平  蔺卿 《干旱区地理》2011,(4)

土壤碳库动态及其驱动机制是陆地生态系统碳循环与全球变化研究的热点问题之一。随着各国对《京都议定书》的重视,农业土壤碳库变化及其源汇效应研究不断加强,但以往研究土壤碳循环主要是针对有机碳,较少考虑无机碳的作用和地位,干旱区土壤无机碳储量巨大,其在区域碳循环过程中的贡献日益显著,这使得干旱区土壤碳循环研究必须同时考虑土壤有机碳和无机碳的行为。国内外关于农业土壤有机碳动态的研究主要围绕农业土壤有机碳储量、固碳潜力等问题展开,研究区多为湿润、半湿润地区;国际上对农业土壤无机碳动态的研究主要集中在干旱区土地管理措施对土壤发生性碳酸盐碳的形成与转化方面,研究方法以稳定同位素技术为主,但目前关于中国干旱区农业土壤无机碳动态的研究还较为薄弱。因此,应加强干旱区绿洲土壤碳循环研究,深入分析干旱区绿洲土壤碳的源/汇效应;探讨土壤无机碳动态变化的机理。  相似文献   

海南岛土壤有机碳空间分布特征及储量   总被引：1，自引：0，他引：1  

张固成  傅杨荣  何玉生  杨奕  郭跃品  张家友  马荣林  李随云 《热带地理》2011,31(6)

利用2005年海南岛生态地球化学调查获得的8713件表层土壤和2197件深层土壤样品,计算分析海南岛土壤有机碳的空间分布特征,结果显示:0～20 cm、0～100 cm、0～180 cm 3个深度的土壤有机碳密度分别为2.86、9.48、13.72 kg/m2,与国内其他典型地区相比,几乎处于最低水平.区域土壤有机碳密度图显示,海南岛土壤有机碳的分布与地貌类型关系密切,高值区分布在山地、丘陵、火山岩台地等地区,其次是平原区,最低为滨海地区.统计显示,土地利用类型、土类不同,土壤有机碳密度差异明显,不同地类土壤有机碳密度:园地＞林地＞其他土地＞耕地,土壤有机碳主要贮存在林地和耕地中;不同土类土壤有机碳密度:黄壤＞赤红壤＞砖红壤＞水稻土＞燥红土,土壤有机碳主要贮存在砖红壤、赤红壤和水稻土中;0～180 cm土壤有机碳库储量为478.13 Mt.  相似文献   

中国产业结构变动的碳排放效应研究——基于省级面板数据   总被引：2，自引：0，他引：2  

肖慧敏 《地域研究与开发》2011,30(5):84-87,92

在二氧化碳(CO2)排放影响因素的模型框架内,利用1995—2008年中国省级的面板数据,着重分析产业结构演变对CO2排放的影响。结果表明,产业结构演进决定CO2排放的基本走向,刚性产业结构演进特征使单位CO2排放居高不下;二产主导的产业结构对我国CO2排放产生了明显的增速效应,延缓了CO2排放倒"U"型变化过程。因此,依托低碳经济助推产业结构升级,优化第一、第二产业内部结构,大力发展第三产业,转向低能耗低CO2排放的产业结构是中国低碳经济发展的必由之路。  相似文献