台湾河海输运系统宿命整合研究综述     

赵强  修宗祥 《地球科学进展》2013,28(1):31-38

台湾河海输运系统宿命研究是一个“从源到汇”的整合性研究计划,包括FATES-KP,FATES-COMMARC和FATES-HYPER 3个独立计划,自2003年启动至今已历时9年,分阶段滚动发展,取得了众多研究成果.该研究计划试图查清在构造活跃的热带季风气候区,并常有台风侵袭的浪控弱潮海岸环境下,沉积物在山区小径流、窄陆架、陆坡及海底峡谷之间的物质分散机制,且随着研究的深入,研究区逐步向南海北部、台湾海峡以及冲绳海槽扩展,在南海“从源到汇”的研究中一枝独秀.通过综述台湾河海输运系统宿命整合研究计划,对其研究方法、内容、取得的成果及遇到的问题进行了简要分析,以期为大陆南海北部“从源到汇”的研究提供借鉴.  相似文献   

气候政策建模研究综述:基于文献计量分析   总被引：2，自引：0，他引：2  

魏一鸣  米志付  张皓 《地球科学进展》2013,28(8):930-938

利用SCI-E和SSCI网络版数据库,使用文献计量方法对1981—2012年间气候政策建模领域的科学产出进行分析。通过对气候政策建模领域的基本特征分析,发现气候政策建模是一个多学科交叉的领域;发达国家在此领域的实力明显强于发展中国家,欧美占据主导地位。通过对关键词的词频分析,发现气候政策建模领域的6个研究热点:减排机制、不确定性、成本效益分析、发展情景、技术进步和公平性。分析还发现,此领域最主流的分析框架是综合评估模型,最主要的模型方法有最优化模型、可计算一般均衡模型和模拟模型;行为模型和数据包络分析模型具有很强的应用潜力。通过对中国在该领域国际地位的分析,提出了该领域发展的相关建议。  相似文献   

Historical extension of operational NDVI products for livestock insurance in Kenya     

《International Journal of Applied Earth Observation and Geoinformation》2014

Droughts induce livestock losses that severely affect Kenyan pastoralists. Recent index insurance schemes have the potential of being a viable tool for insuring pastoralists against drought-related risk. Such schemes require as input a forage scarcity (or drought) index that can be reliably updated in near real-time, and that strongly relates to livestock mortality. Generally, a long record (>25 years) of the index is needed to correctly estimate mortality risk and calculate the related insurance premium. Data from current operational satellites used for large-scale vegetation monitoring span over a maximum of 15 years, a time period that is considered insufficient for accurate premium computation. This study examines how operational NDVI datasets compare to, and could be combined with the non-operational recently constructed 30-year GIMMS AVHRR record (1981–2011) to provide a near-real time drought index with a long term archive for the arid lands of Kenya. We compared six freely available, near-real time NDVI products: five from MODIS and one from SPOT-VEGETATION. Prior to comparison, all datasets were averaged in time for the two vegetative seasons in Kenya, and aggregated spatially at the administrative division level at which the insurance is offered. The feasibility of extending the resulting aggregated drought indices back in time was assessed using jackknifed R² statistics (leave-one-year-out) for the overlapping period 2002–2011. We found that division-specific models were more effective than a global model for linking the division-level temporal variability of the index between NDVI products. Based on our results, good scope exists for historically extending the aggregated drought index, thus providing a longer operational record for insurance purposes. We showed that this extension may have large effects on the calculated insurance premium. Finally, we discuss several possible improvements to the drought index.  相似文献   

The importance of expert knowledge in conservation planning – Comment to an article by C.J. Klein et al.     

《Marine Policy》2014

This paper comments and discusses the article ‘Evaluating the influence of candidate terrestrial protected areas on coral reef condition in Fiji׳ by Klein et al. in Marine Policy 44 2014. Klein et al. integrate land-sea planning by optimising the design of Fiji׳s expanded protected area network to benefit coral reefs, while maintaining a terrestrial network that is representative of Fiji׳s various terrestrial ecosystems. They discuss the benefits of various spatial conservation models compared to a candidate protected area network proposed by Fiji׳s Protected Area Committee (FPAC), which is based on expert knowledge and a scoring system. This paper argues that their analyses are best interpreted as the FPAC network outperforming the models proposed by Klein et al. in protecting terrestrial biodiversity. The FPAC network performs better because it includes data that was not available for spatial modelling, especially the percentage of endemic species per ecosystem and the practicalities of protecting an area earmarked for conservation. This suggests that expert knowledge can be an important resource for conservation planning, especially in developing countries, and that spatial conservation planning should harness this knowledge.  相似文献   

Changing maritime scenarios. The geopolitical dimension of the EU Atlantic Strategy     

《Marine Policy》2014

The European Union׳s Integrated Maritime Policy (EU IMP) is being developed in the framework of a process that is reshaping maritime geographical scenarios and world geopolitics. This process is characterised by a change in States׳ territoriality resulting from their jurisdictional expansion. Over 60% of coastal States in the world possess territory with a more extensive maritime component than the terrestrial component which helps to reaffirm the fragmentation of maritime space and stresses the national vision of the oceans. Unlike the process of ocean space fragmentation that results from its nationalisation the EU Integrated Maritime Policy has a global and cooperative vision, which is particularly evident in the Atlantic Strategy. In this context, this article aims to: (i) provide a first estimate of the size and extent of the territorial changes resulting from jurisdictional claims available to date and their mapping; (ii) consider the case of the European Union as one of special significance with its express policy of maritime spatial projection. The conclusions point to a redefinition of the large territorial pieces of the global geopolitics puzzle and the emergence of a new Atlanticism associated with the EU׳s maritime policy.  相似文献   

Assessing benthic ecological status in coastal area near Changjiang River estuary using AMBI and M-AMBI   总被引：4，自引：0，他引：4  

刘录三  李宝泉  林岿璇  蔡文倩  王全超 《中国海洋湖沼学报》2014,32(2):290-305

The Changjiang （Yangtze） River estuary has been subject to a variety of anthropogenic pressures in recent decades. To assess the ecological health of the coastal benthic ecosystem adjacent to the estuary, three surveys were conducted in 2005, 2009, and 2010. The AZTI＇s Marine Biotic Index （AMBI） and multivariate-AMBI （M-AMBI） were used to analyse the benthic ecological status of this coast. The AMBI indicate that the ecological status of the coast adjacent to the Changjiang River estuary was only slightly degraded in all 3 years. In contrast, the M-AMBI indicated that the ecological status was seriously degraded, a result that is most likely due to pollution and eutrophication induced by human activities. The assessment of the coast＇s ecological status by the AMBI was not in agreement with that of the M-AMBI at some stations because of lower biodiversity values at those sites. The analysis of the two indices integrated with abiotic parameters showed that the M-AMBI could be used as a suitable bio-indicator index to assess the benthic ecological status of the coast adjacent to the Changjiang River estuary. The reference conditions proposed for the coast of the Changjiang River estuary should be further evaluated in future studies. Designation of local species could also provide an important reference for Chinese waters. To improve the reliability of AMBI and M-AMBI, further research into the ecology of local species is required to understand their arrangement in ecological groups.  相似文献   

An Introduction to the Integrated Climate Model of the Center for Monsoon System Research and its simulated influence of El Niño on East Asian-western North Pacific climate     

Ping Huang  Pengfei Wang  Kaiming Hu  Gang Huang  Zhihua Zhang  Yong Liu  Bangliang Yan 《大气科学进展》2014,31(5):1136-1146

This study introduces a new global climate model--the Integrated Climate Model （ICM）--developed for the seasonal prediction of East Asian-western North Pacific （EA-WNP） climate by the Center for Monsoon System Research at the Institute of Atmospheric Physics （CMSR, IAP）, Chinese Academy of Sciences. ICM integrates ECHAM5 and NEMO2.3 as its atmospheric and oceanic components, respectively, using OASIS3 as the coupler. The simulation skill of ICM is evaluated here, including the simulated climatology, interannual variation, and the influence of E1 Nifio as one of the most important factors on EA-WNP climate. ICM successfully reproduces the distribution of sea surface temperature （SST） and precipitation without climate shift, the seasonal cycle of equatorial Pacific SST, and the precipitation and circulation of East Asian summer monsoon. The most prominent biases of ICM are the excessive cold tongue and unrealistic westward phase propagation of equatorial Pacific SST. The main interannual variation of the tropical Pacific SST and EA-WNP climate E1 Nifio and the East Asia-Pacific Pattern--are also well simulated in ICM, with realistic spatial pattern and period. The simulated E1 Nifio has significant impact on EA-WNP climate, as in other models. The assessment shows ICM should be a reliable model for the seasonal prediction of EA-WNP climate.  相似文献   

Towards long-multitemporal change detection using SVI differencing by integrated DWT–ISOCLUS: a model for forest temporal dynamics mapping     

《International Journal of Digital Earth》2013,6(2):108-132

Abstract

Characterisation and mapping of land cover/land use within forest areas over long-multitemporal intervals is a complex task. This complexity is mainly due to the location and extent of such areas and, as a consequence, to the lack of full continuous cloud-free coverage of those large regions by one single remote sensing instrument. In order to provide improved long-multitemporal forest change detection using Landsat MSS and ETM + in part of Mt. Kenya rainforest, and to develop a model for forest change monitoring, wavelet transforms analysis was tested against the ISOCLUS algorithm for the derivation of changes in natural forest cover, as determined using four simple ratio-based Vegetation Indices: Simple Ratio (SR), Normalised Difference Vegetation Index (NDVI), Renormalised Difference Vegetation Index (RDVI) and modified simple ratio (MSR). Based on statistical and empirical accuracy assessments, RDVI presented the optimal index for the case study. The overall accuracy statistic of the wavelet derived change/no-change was used to rank the performances of the indices as: RDVI (91.68%), MSR (82.55%), NDVI (79.73%) and SR (65.34%). The integrated discrete wavelet transform–ISOCLUS (DWT–ISOCLUS) result was 42.65% higher than the independent ISOCLUS approach in mapping the change/no-change information. The methodology suggested in this study presents a cost-effective and practical method to detect land-cover changes in support of decision-making for updating forest databases, and for long-term monitoring of vegetation changes from multisensor imagery. The current research contributes to Digital Earth with regards to geo-data acquisition, data mining and representation of one forest systems.  相似文献   

Biomagnification of persistent chlorinated and brominated contaminants in food web components of the Yellow Sea     

Gyo-Hyuk Byun  Hyo-Bang Moon  Jung-Hwa Choi  Jeomshik Hwang  Chang-Keun Kang 《Marine pollution bulletin》2013

Concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) were measured in 32 species inhabiting the Yellow Sea to assess their bioaccumulation potentials. The concentrations in these samples were lower than those reported for other countries or locations. Relatively high levels of BDE 209 in biota suggest an ongoing source of deca-BDE technical mixing within the Yellow Sea. The accumulation profiles of PCBs were uniform between species, but the concentrations of OCPs and PBDEs varied widely. Pelagic and benthic food-chain components were separated by their δ¹³C values. Significant positive correlations between δ¹⁵N and PCB 153, PCB 138, p,p′-DDE, oxy-chlordane, and trans-nonachlordane were found only for pelagic consumers, indicating that the pelagic food chain is an important bioaccumulation pathway for selected PCB and OCP compounds. The other compounds did not show any biomagnification through benthic and pelagic food chains, suggesting the lower bioaccumulation potentials of these contaminants.  相似文献   

Effects of an oil spill on benthic community production and respiration on subtropical intertidal sandflats     

Li-Hua Lee  Hsing-Juh Lin 《Marine pollution bulletin》2013

This study determined effects of an oil spill on subtropical benthic community production and respiration by monitoring CO₂ fluxes in benthic chambers on intertidal sandflats during emersion before and after an accidental spill. The oil spill decreased sediment chlorophyll a concentrations, altered benthic macrofaunal community, and affected ecological functioning by suppressing or even stopping microalgal production, increasing bacterial respiration, and causing a shift from an autotrophic system to a heterotrophic system. Effects of the oil spill on the macrofauna were more severe than on benthic microalgae, and affected sedentary infauna more than motile epifauna. Despite the oil spill’s impact on the benthic community and carbon metabolism, the affected area appeared to return to normal in about 23 days. Our results suggest that the prompt response of benthic metabolism to exposure to petroleum hydrocarbons can serve as a useful indicator of the impact of an oil spill.  相似文献