土地利用方式对荒漠草地生物量分配及碳密度的影响     

刘文亭  卫智军  吕世杰  孙世贤  代景忠 《中国沙漠》2016,36(3):666-673

草地生态系统群落生物量的分配模式对于研究生态系统碳储量和碳循环有着重要的意义。为了解内蒙古荒漠草地群落生物量垂直分配格局,从不同土地利用方式着手探讨群落生物量不同成层性分配规律并估算荒漠草地生物量碳密度。结果表明:(1)人工灌溉草地灌木层生物量明显高于放牧和原生草地,草本层生物量表现出灌溉草地>原生草地>放牧草地,而凋落物层表现出灌溉草地<放牧草地<原生草地,地上生物量集中在草本层(60%以上),地下0~10 cm生物量大于其他层生物量(P<0.05)。(2)灌木层生物量、草本层生物量、凋落物层间存在极显著的相关关系(P<0.0001);地下各层生物量之间存在极显著相关关系(P<0.0001);且灌溉草地与原生草地群落地上层生物量与地下层生物量之间存在显著相关关系(P<0.05),故可以建立生物量成层性分配模型。(3)生物量碳密度原生草地<放牧草地<灌溉草地。  相似文献   

西藏那茶淌北铅锌矿床矽卡岩地球化学特征及其成因     

戴成龙 《地质与勘探》2017,53(5):991-1000

那茶淌北铅锌矿床位于西藏冈底斯成矿带东段北部,主要由矽卡岩铅锌矿体组成,是一个典型的矽卡岩型矿床。笔者通过对矿床内的矽卡岩、大理岩(灰岩)、黑云母花岗岩的地球化学对比分析表明:在主量元素方面,显示Si、Al、Fe、Ti、Mg、Ca、Mn等元素在矽卡岩、大理岩、黑云母花岗岩之间发生明显的交换;在稀土元素方面,矽卡岩、大理岩和黑云母花岗岩均具有LREE富集,HREE亏损,并且发育Eu和Ce负异常和相似的REE配分模式,说明矽卡岩的成因与大理岩、黑云母花岗岩具有一定关系。结合三种不同岩性的地球化学特征,强烈的轻、重稀土分异,Eu、Ce负异常,推测矽卡岩由中高温还原热液交代碳酸盐而成,矽卡岩成岩过程中可能有少量海水加入。  相似文献   

Biodegradation of Polychlorinated Biphenyls Using a Moving‐Bed Biofilm Reactor          下载免费PDF全文

Bin Dong  Han‐Yu Chen  Yang Yang  Qun‐biao He  Xiao‐Hu Dai 《洁净——土壤、空气、水》2015,43(7):1078-1083

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虚拟水战略新论的社会经济效益分析——以石羊河流域民勤县为例     

尚海洋  张志强  王岱  刘正汉 《冰川冻土》2015,37(3):818-825

虚拟水战略已经被认为是一种提高全球水资源利用效率和缺水地区获得水安全的有效工具. 虚拟水战略新论指出, 应充分利用各种社会资源, 打通优化配置水资源(实体水和虚拟水)的渠道. 虚拟水战略能否有效实施的首要任务, 是地区产业结构内部配置的优化. 本文在估算民勤县主要农作物虚拟水量的基础上, 利用部门水效益分析了虚拟水由农业(种植业)部门向第二、三产业转移的三种情景下产生的净效益和创造的社会就业机会, 刻画了实施虚拟水战略的重要理论意义, 佐证了虚拟水战略全新定义的现实意义.  相似文献   

Orbital period investigation of some short-period sdB-type eclipsing binaries     

S.-B. Qian  L.-Y. Zhu  L. Liu  Z.-B. Dai  J.-J. He  W.-P. Liao  E.-G. Zhao  S. Zola  E. Kuligowska  M. Winiarski 《Astrophysics and Space Science》2010,328(1-2):113-117

Analysis of over 15 years of V-band and Wing three filter near-IR photometry of the bright M5Ib-II supergiant has been carried out. Wavelet analysis of these data reveals that the star pulsates with several complicated oscillation modes. Different time scales of variability are identified, and with the aid of discrete Fourier analysis, depending on the filter, up to seven significant pulsation modes are identified and their frequencies and amplitudes extracted. The Long Secondary Period (LSP) with a mean period of ～1343 d has been identified, as well as other periods of the order of ～125 d. The longer period appears to be attributed to the radial pulsational mode, while the various peaks near ～125 d appear to arise from stochastically excited p-modes. After removing the light contribution of the 5th magnitude binary companion and calibrating the intermediate-band photometry to the Wing photometric system, TiO (719 nm) and near-IR (B-C) Wing color indices were formed. These indices have been calibrated with T _eff, while the Wing-C bandpass (1025 nm) serves as a proxy for bolometric magnitude and was transformed to approximate m _bol. Finally, the derivation of the variations in the star’s temperature, luminosity and radius is straightforward.  相似文献   

从城市到乡村:节事及节事旅游在乡村地域的发展动因及其应用前景   总被引：1，自引：0，他引：1  

戴林琳 《地域研究与开发》2012,31(6):76-81,86

对20世纪60年代以来重要的中西方节事及节事旅游文献进行了回顾和总结,归纳和分析了城市领域内节事及节事旅游发展的总体趋势、最新进展及主要研究成果;在此基础上,以城市领域节事及节事研究进展为参照,通过比较研究的方式,依次阐释了乡村地区节事及节事旅游的发展进程、基本内涵、类型划分及发展动因;借鉴西方国家乡村节事发展经验,结合我国乡村节事发展中的具体问题,对其应用前景进行了分析和展望,以期对国内乡村节事发展及相关研究提供有益的理论指导与实践参照。  相似文献   

Influence of HITRAN Database Updates on Retrievals of Atmospheric CO2 from Near-Infrared Spectra          下载免费PDF全文

DAI Tie  SHI Guangyu  ZHANG Xingying  XU Na 《Acta Meteorologica Sinica》2012,26(5):629-641

The line-transition parameters of the High Resolution Transmission (HITRAN) 2008 database have been updated relative to previous editions. The transmission spectra and sensitivity to changes in CO2 concentrations using line parameters from the HITRAN 2004 and HITRAN 2008 databases are compared to evaluate the effect of the database updates on retrievals of carbon dioxide vertical columns from nearinfrared reflected sunlight. This comparison is done in three spectral regions covering the 2.06-, 1.61-, and 1.58-μm CO2bands used by the Greenhouse Gases Observatory Satellite (GOSAT) instrument and the planned successor to the Orbiting Carbon Observatory (OCO). The updates to the HITRAN database have the largest effects on the transmittance and the off-line to on-line transmittance ratio in the 2.06-μm region and the smallest effects on these parameters in the 1.58-μm region. The influence of the updates to the HITRAN database on the off-line to on-line ratio calculation in the narrow spectral region 4855-4880 cm-1 could be equivalent to a change in CO2 of more than 50 ppmv. Use of the HITRAN 2004 database will lead to an underestimate of the column CO2abundance in the 2.06- and 1.61-μm spectral regions, whereas it will lead to an overestimate of the column CO2abundance in the 1.58-μm spectral region.  相似文献   

1961—2010年桂北晚稻寒露风特征分析   总被引：5，自引：0，他引：5  

戴剑波  高静  杨爱萍  霍治国  姜会飞 《气象与减灾研究》2012,(3):57-62

利用广西融安1961—2010年逐日气温和降水量数据,按2008年中国气象局颁布的"寒露风等级气象行业标准",统计该地区近50 a寒露风发生情况。结果表明,近50 a晚稻寒露风屡年发生;从危害日数和天气过程次数来看,以轻度和湿冷型为主;从危害敏感期来看,抽穗开花期影响最严重,花粉母细胞减数分裂期次之,幼穗分化期影响相对较小;从寒露风出现早晚、危害日数和过程次数来看,寒露风年际变化较大,且自21世纪以来寒露风危害呈现减弱趋势。  相似文献   

环境伦理与区域可持续发展(英文)   总被引：2，自引：1，他引：1  

郑度  戴尔阜 《地理学报(英文版)》2012,22(1):86-92

The scientific environmental ethics plays a key role in the recognition of the human-environment interactions. Modern environmental ethics is the philosophical re-thinking of modern human race environmental behavior. The development of environmental ethics theory, as well as its application in reality, determines the viewpoints of environmental ethics. Sustainable development implies harmony on human-environment interactions and inter-generation responsibility, with emphasis on a harmonious relationship among population, resources, environment and development, so as to lay a sustainable and healthy foundation of resources and environment for future generations. The harmonious society construction in China that is raised by the Chinese central government should be covered by environmental ethics. The connotation of open environmental ethics includes a respect for nature, care for the individual human race, and respect for the development of future generations, which means giving consideration to natural values, individual and human race benefits and welfare across generations. The role of environmental ethics in regional development consists of cognition, criticism, education, inspiration, adjusting, legislation and promoting environmental regulations. The major problems in regional development are extensive resource exploration, fast population growth, irrational industrial structure, unfair welfare distribution and the twofold effects of science and technology development. The formulation of environmental ethics that aims at regional sustainable development, can not only harmonize the relationship of population, resource, environment and economic development, but also guide behavior selection, push social and political system transformation, strengthen the legal system, and raise environmental awareness of the public.  相似文献   

中国西南地区纵向岭谷地形对区域生态地理格局的作用(英文)     

潘韬  吴绍洪  何大明  戴尔阜  刘玉洁 《地理学报(英文版)》2012,22(5):825-842

China’s southwestern special terrain pattern as parallel arrangement between longitudinal towering mountains and deep valleys has significant effects on the differentiation of local natural environment and eco-geographical pattern in this region.The 1:50,000 Digital Elevation Model(DEM) data of Longitudinal Range-Gorge Region(LRGR),meteorological observation data from the station establishment to 2010,hydrological observation data,Normalized Difference Vegetation Index(NDVI) and Net Primary Productivity(NPP) products of MOD13 and MOD17 as well as 1:1,000,000 vegetation type data were used.Moisture indices including surface atmospheric vapor content,precipitation,aridity/humidity index,surface runoff,and temperature indices including average temperature,annual accumulated temperature,total solar radiation were selected.Based on ANUSPLIN spline function,GIS spatial analysis,wavelet analysis and landscape pattern analysis,regional differentiation characteristics and main-control factors of hydrothermal pattern,ecosystem structure and function in this region were analyzed to reveal the effects of terrain pattern on regional differentiation of eco-geographical elements.The results show that:influenced by terrain pattern,moisture,temperature and heat in LRGR have shown significant distribution characteristics as intermittent weft differences and continuous warp extension.Longitudinal mountains and valleys not only have a north-south corridor function and diffusion effect on the transfer of major surface materials and energy,but also have east-west barrier function and blocking effect.Special topographic pattern has important influences on vegetation landscape diversity and spatial pattern of ecosystem structure and function,which is the main-control factor on vegetation landscape diversity and spatial distribution of ecosystem.Wavelet variance analysis reflects the spatial anisotropy of environmental factors,NDVI and NPP,while wavelet consistency analysis reveals the control factors on spatial distribution of NDVI and NPP as well as the quantitative relationship with control degree.Special terrain pattern in LRGR is the major influencing factor on eco-geographical regional differentiation in this region.Under the combined effect of zonality and non-zonality laws with "corridor-barrier" function as the main characteristic,special spatial characteristics of eco-geographical regional system in LRGR is formed.  相似文献