Improving benthic monitoring by combining trawl and grab surveys     

Jørgensen LL  Renaud PE  Cochrane SK 《Marine pollution bulletin》2011,62(6):1183-1190

Environmental monitoring is performed on seafloor communities since these organisms are relatively stationary and integrate the environmental conditions over many years. Standard practices involve sampling by grab. Epifaunal taxa, often missed by grab sampling, are likely to have different ecological functions. We investigate how current environmental assessments represent the benthic community as a whole by comparing taxonomic and functional components sampled by grabs and epibenthic trawls. Faunal communities sampled by trawl (filtrating or predator, epifauna) and grab (infaunal, detrivore) differs widely by sampling distinct functional components, and these may be expected to respond to different human-induced stressors. Neither component appears to be a good surrogate for the community as a whole. We suggest a benthic monitoring by combining both techniques. Sustainable ecosystem functioning is intimately tied to the health of both components of the benthic community, and is recognized as an important goal by signatories of the Convention on Biological Diversity.  相似文献   

Integration of MODIS data and Short Baseline Subset (SBAS) technique for land subsidence monitoring in Datong, China     

Chao-ying Zhao  Qin Zhang  Chengsheng Yang  Weibao Zou 《Journal of Geodynamics》2011,52(1):16-23

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Time-lapse processing of 2D seismic profiles with testing of static correction methods at the CO₂ injection site Ketzin (Germany)     

Peter Bergmann  Can YangStefan Lüth  Christopher JuhlinCalin Cosma 《Journal of Applied Geophysics》2011,75(1):124-139

The Ketzin project provides an experimental pilot test site for the geological storage of CO₂. Seismic monitoring of the Ketzin site comprises 2D and 3D time-lapse experiments with baseline experiments in 2005. The first repeat 2D survey was acquired in 2009 after 22 kt of CO₂ had been injected into the Stuttgart Formation at approximately 630 m depth. Main objectives of the 2D seismic surveys were the imaging of geological structures, detection of injected CO₂, and comparison with the 3D surveys. Time-lapse processing highlighted the importance of detailed static corrections to account for travel time delays, which are attributed to different near-surface velocities during the survey periods. Compensation for these delays has been performed using both pre-stack static corrections and post-stack static corrections. The pre-stack method decomposes the travel time delays of baseline and repeat datasets in a surface consistent manner, while the latter cross-aligns baseline and repeat stacked sections along a reference horizon.Application of the static corrections improves the S/N ratio of the time-lapse sections significantly. Based on our results, it is recommended to apply a combination of both corrections when time-lapse processing faces considerable near-surface velocity changes. Processing of the datasets demonstrates that the decomposed solution of the pre-stack static corrections can be used for interpretation of changes in near-surface velocities. In particular, the long-wavelength part of the solution indicates an increase in soil moisture or a shallower groundwater table in the repeat survey.Comparison with the processing results of 2D and 3D surveys shows that both image the subsurface, but with local variations which are mainly associated to differences in the acquisition geometry and source types used. Interpretation of baseline and repeat stacks shows that no CO₂ related time-lapse signature is observable where the 2D lines allow monitoring of the reservoir. This finding is consistent with the time-lapse results of the 3D surveys, which show an increase in reflection amplitude centered around the injection well. To further investigate any potential CO₂ signature, an amplitude versus offset (AVO) analysis was performed. The time-lapse analysis of the AVO does not indicate the presence of CO₂, as expected, but shows signs of a pressure response in the repeat data.  相似文献   

星站差分GPS系统在地震监测中的应用     

王雷  朱志春  张毅  顾春雷  徐如刚  袁洁浩 《华南地震》2011,31(2):110-116

为考察SF-2050星站差分GPS在实际使用中的定位精度、收敛时间与定化重复性等性能指标.对其进行了定位功能测试,详述了测试过程与测试结果的得出,证明该系统具有定位精度高、定位重复性好等优点,辅以一定的使用技巧,可进一步提高其工作效能,能够满足地震监测行业中测点定位的要求.  相似文献   

淮安市洪泽盐盆地质环境监测网建设的实践          下载免费PDF全文

张以高  丁厚金  喻永祥 《江苏地质》2011,35(4):413-417

随着岩盐矿床逐步得到开发利用,盐矿开采过程中引发的地质环境问题也日益受到人们的关注,而目前对盐矿开采引发的地面沉降和地下水污染等地质环境问题以理论研究居多,鲜有实际监测数据支撑,虽然有少量盐矿开展了监测工作,但其监测范围也多限于单个矿区、监测内容多为单个地质环境问题(如地面沉降的专项监测)。洪泽盐盆地质环境监测网是我国首个在整个盐盆范围内(覆盖现有开采区及规划开采区)统一规划建设的、集地面沉降和地下水污染为一体的综合监测网络,它的建设不仅极大地全面推进了洪泽盐盆矿山地质环境保护的进程,而且其建设经验、监测手段、运行管理模式也为其他地区盐类矿床的地质环境保护提供了有效的借鉴,同时,长期的监测数据也能为进一步研究盐矿开采区的地质环境问题提供可靠的基础资料。  相似文献   

质点振动速度监测在爆破掘进工程中的应用     

黄来源  周积响 《城市地质》2011,6(1):60-63

工程爆破施工过程中如何控制其对周围建筑物、正在施工项目和处于养护龄期内的混凝土结构的影响一直是爆破施工中的实际问题,直接关系爆破施工的单响药量和施工进度。隧道爆破掘进施工中为了追求施工进度,往往在爆破方案中使用较大的单响装药量,从而忽略了大药量爆破产生的冲击波效应对隧道岩壁、已有结构的破坏,本文简单介绍了施工前或施工中,进行质点振动速度监测的实际应用。  相似文献   

Irish estuaries: Water quality status and monitoring implications under the water framework directive     

Michael Hartnett  James G. Wilson  Stephen Nash 《Marine Policy》2011

The status of water quality of Irish estuaries is reviewed; this sheds light on the rationale behind the design of the national monitoring programme. Relative to other EU Member States, Ireland's coastal monitoring programme is relatively young and not as advanced. The monitoring programmes in Ireland pre Water Framework Directive (WFD) were structured on a salinity-based typology, with an emphasis on quantifying the variability of the component elements. Although monitoring is a significant obligation under the WFD, there is little guidance on developing monitoring protocols; Member States are developing ad hoc monitoring programme. The Irish Environmental Protection Agency (EPA), responsible authority, undertook research programmes to assist design and implementation of the WFD. A substantial new national monitoring programme was developed. However, the Irish programme is not optimised; the programme is being refined to include elements not yet covered, notably the biota. New research, by the authors, aims to develop a robust approach towards monitoring integrating data and model results. This paper presents changes in Irish marine water quality monitoring policy and some of the associated research necessary to change policy.  相似文献   

Ecosystem-based marine spatial management: Review of concepts, policies, tools, and critical issues   总被引：1，自引：0，他引：1  

Stelios Katsanevakis  Vanessa Stelzenmüller  Andy South  Thomas Kirk Sørensen  Peter J.S. Jones  Sandy Kerr  Fabio Badalamenti  Christos Anagnostou  Patricia Breen  Guillem Chust  Giovanni D’Anna  Mike Duijn  Tatiana Filatova  Fabio Fiorentino  Helena Hulsman  Kate Johnson  Aristomenis P. Karageorgis  Ingrid Kröncke  Simone Mirto  Carlo Pipitone  Susan Portelli  Wanfei Qiu  Henning Reiss  Dimitris Sakellariou  Maria Salomidi  Luc van Hoof  Vassiliki Vassilopoulou  Tomás Vega Fernández  Sandra Vöge  Anke Weber  Argyro Zenetos  Remment ter Hofstede 《Ocean & Coastal Management》2011,54(11):807-820

Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   

HY-1B CZI海岸带动态监测系统设计与实现     

梁建  宋平舰  崔廷伟  任广波  赵文静 《海洋通报》2011,30(1):94-99

HY-1B卫星是我国第二颗自主海洋卫星,针对其搭载的4波段海岸带成像仪(CZI)获取的数据,设计并基于IDL语言开发了一个专用的可视化数据处理与应用系统.该系统以黄河口为重点研究区域,对部分算法进行了优化和适应性改造,具备HY-1BCZI数据导入、预处理、海岸带动态监测产品制作、产品输出、数据批处理等功能,并能够进行数...  相似文献   

沉降监测数据管理与分析系统的研制     

张菊清  张勤  李斌 《地球科学与环境学报》2001,23(1):75-78

沉降监测是对变形监测体进行定期的观测，然后应用平差和数理统计理论,对观测数据进行分析、判断。在简要叙述了沉降监测的基本原理上，给出了沉降监测数据管理及分析系统的结构，并对各模块的功能作了简单的介绍。  相似文献