Rebuilding viable spawner patches of the overfished Spisula solida (Mollusca: Bivalvia): a preliminary contribution to fishery sustainability     

Joaquim  Sandra; Gaspar  Miguel B.; Matias  Domitilia; Ben-Hamadou  Radhouan; Arnold  William S. 《ICES Journal of Marine Science》2008,65(1):60-64

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植被恢复工程对黄河中游12个典型流域水热平衡的影响研究     

林依雪  李艳忠  余文君  卜添荟  黄蓉 《地理研究》2020,39(11):2593-2606

中国已成为全球植被迅速变绿贡献最大的国家,但植被变绿对水量平衡和能量收支平衡影响的相关研究有待加强。本文以植被恢复典型区域黄河中游12个流域为例,利用遥感植被指数NDVI和常规气象数据,基于布迪克假设和水热平衡指数（Water-Energy Ratio, WER）,分析了植被变绿的时空变化格局及其对水热平衡的影响。结果表明：① 傅抱璞模型中反映流域属性的参数w在12个流域的平均值为2.9,略大于模型的缺省值2.6。参数w与NDVI拟合的Pearson相关系数介于0.31~0.75,拟合性能较好。② 1982—2016年NDVI在12个流域均呈现显著增加趋势,尤其以植被恢复工程实施后更为显著（p<0.001）。相对1982—1999年,2000—2016年NDVI相对变化率在9.1%~17.5%之间,均值为12.9%,显著植被变绿已导致水热平衡向可利用水分减少、可利用能量增加方向转化。③ NDVI对WER变化的绝对贡献率达到77.5%,植被变绿已经成为黄河中游12个流域水热平衡变化的主导因素,其次为气候要素。植被的持续变绿带来了一些不利影响,植被恢复工程的生态效应研究有待进一步深入研究。  相似文献   

基于生物–环境–服务功能模型的三江源高寒草甸湿地不同恢复措施效果评价   总被引：1，自引：0，他引：1  

苏晓虾  毛旭锋  魏晓燕  令建康  张艳春  包先霞 《地理科学》2020,40(8):1377-1384

研究以青海省三江源区退化草甸湿地为研究区,对湿地环境和功能进行评估,构建了基于生物（Biology）-环境（Environment）-服务功能（Service）的BES模型（涉及3个生物指标,4个环境指标,8种生态系统服务功能指标）评估3种湿地恢复技术（I-补播草种+生长期封育;II-围栏封育和III-防鼠样地）对湿地恢复的效果。基于2017年和2018年的监测数据,计算湿地综合健康指数（Comprehensive healthy index,CHI）和净变动指数（Net variation index,NVI）,分析不同恢复措施下湿地健康的恢复过程及其恢复程度。结果表明：① 3种修复技术在湿地恢复中均取得较好的效果。湿地的综合健康指数从2016年未实施任何措施时的0.499分别上升至0.712、0.716和0.650,湿地健康水平由警戒状态恢复至良好状态;② 评价期内恢复技术I和II对湿地恢复效果均好于恢复技术III,但未发现恢复技术I和II之间存在显著差别;③ 高寒湿地生物指标与供给指标恢复速度较快、恢复程度较好,而土壤支持等指标恢复速度较慢、幅度较小。补播草种有助于短时、高效地恢复湿地植被,而实现土壤和功能的全面恢复还需要结合封育等更多的措施和更长的周期。  相似文献   

我国海洋生态修复政策现状、问题及建议          下载免费PDF全文

陈克亮  吴侃侃  黄海萍  姜玉环 《应用海洋学学报》2021,40(1):170-178

通过系统梳理并分析了近年来国家和沿海地方在制订和实施海洋生态修复政策的现状和实施概况,从管理政策、技术政策和经济政策三个方面进行研究分析认为:目前海洋生态修复的政策大多分散在岸线保护、滨海湿地保护、围填海管控修复的单项法律法规、政策文件、相关规划或标准中,国家和地方层面对于系统开展海洋生态修复工程尚缺少针对性和系统性的...  相似文献   

Tidal Asymmetry Changes in a Shallow Mud Estuary by a Restoration Project     

LIANG Huidi  KUANG Cuiping  GU Jie  MA Yue  CHEN Kuo  LIU Xu 《中国海洋大学学报(英文版)》2019,(2):339-348

The tidal asymmetry-induced siltation below tidal barriers is a worldwide problem that restricts regional socio-economic and environmental development. The hydrodynamic processes of the small mud estuary also feature a high uncertainty after estuary restoration measures. In this study, a hydrodynamic model based on the MIKE21 is used to quantify the responses of tidal asymmetry to a two-phase restoration project in Shuanglong Estuary, Bohai Bay, China. According to the numerical modeling results, the tidal flat removal in the upper estuary(first-phase restoration) induces the flood asymmetry switching to the ebb asymmetry in unrestored reach but enhances flood asymmetry in widening restored reach. Although the tidal asymmetry reverts to flood-dominated pattern after full restoration over the estuary, the imbalance between flood and ebb velocities is relieved. A possible net sediment transport pattern based on a comparison of dominant asymmetric current and actual sediment transport period shows net sediments in the upper estuary and inlet transport seaward and landward, respectively, in the first-phase restoration, whereas landward net sediment transport occurs in the whole estuary under the second-phase restoration scenario. Given these results, we assume that a switch from the flood-dominated estuary to ebb-dominated estuary can be caused by redesigning the cross-sectional profile. The quantitative comparison of Lagrangian residual currents also implies that a channel–shoal structure rather than a flat bathymetry can promote the mass transport. Therefore, reshaping the channel–tidal flat system in restoration projects can prevent the sedimentation of the estuary and improve the water environment.  相似文献   

厦门杏林湾生态修复效果评估和保护对策     

庄乾  余兴光  林志兰  温瑞  张继伟  龙邹霞 《海洋开发与管理》2021,38(4):91-98

为加强杏林湾生态环境保护,强化厦门自然保护地选划和滨海湿地保护管理,文章分析自园博园建设以来,海岸带开发对杏林湾生态功能的影响;基于生态系统服务价值理论,通过构建杏林湾生态修复效果评估指标体系,对杏林湾生态修复效果进行评估和分析。研究结果表明:杏林湾生态系统服务价值由2005年的6313.03万元提升至2018年的10415.93万元,区域开发过程中的保护措施对生态系统服务有促进作用,但尚未完全发挥杏林湾应有的价值,原生生境保护有待加强。运用"山水林田湖草"生命共同体和陆海统筹理念提出保护措施:通过划定自然保护地对荒野地进行严格保护,并开展以自然恢复为主的生态修复,从而进一步提升生态价值;针对杏林湾水污染问题,通过湖海共治提升水质,改善生态环境质量。  相似文献   

武汉东湖水生植被的恢复试验研究   总被引：28，自引：4，他引：24  

邱东茹  吴振斌  刘保元  严国安  周远捷 《湖泊科学》1997,9(2):168-174

本文报道了在武汉东湖所作的水生植被恢复的研究结果,分别在东湖水果湖、汤林湖和后湖等三个湖建立水生植被恢复示范区。  相似文献   

Upscaling site‐scale ecohydraulic models to inform salmonid population‐level life cycle modeling and restoration actions – Lessons from the Columbia River Basin          下载免费PDF全文

Joseph M. Wheaton  Nicolaas Bouwes  Peter Mchugh  Carl Saunders  Sara Bangen  Phillip Bailey  Matt Nahorniak  Eric Wall  Chris Jordan 《地球表面变化过程与地形》2018,43(1):21-44

With high‐resolution topography and imagery in fluvial environments, the potential to quantify physical fish habitat at the reach scale has never been better. Increased availability of hydraulic, temperature and food availability data and models have given rise to a host of species and life stage specific ecohydraulic fish habitat models ranging from simple, empirical habitat suitability curve driven models, to fuzzy inference systems to fully mechanistic bioenergetic models. However, few examples exist where such information has been upscaled appropriately to evaluate entire fish populations. We present a framework for applying such ecohydraulic models from over 905 sites in 12 sub‐watersheds of the Columbia River Basin (USA), to assess status and trends in anadromous salmon populations. We automated the simulation of computational engines to drive the hydraulics, and subsequent ecohydraulic models using cloud computing for over 2075 visits from 2011 to 2015 at 905 sites. We also characterize each site's geomorphic reach type, habitat condition, geomorphic unit assemblage, primary production potential and thermal regime. We then independently produce drainage network‐scale models to estimate these same parameters from coarser, remotely sensed data available across entire populations within the Columbia River Basin. These variables give us a basis for imputation of reach‐scale capacity estimates across drainage networks. Combining capacity estimates with survival estimates from mark–recapture monitoring allows a more robust quantification of capacity for freshwater life stages (i.e. adult spawning, juvenile rearing) of the anadromous life cycle. We use these data to drive life cycle models of populations, which not only include the freshwater life stages but also the marine and migration life stages through the hydropower system. More fundamentally, we can begin to look at more realistic, spatially explicit, tributary habitat restoration scenarios to examine whether the enormous financial investment on such restoration actions can help recover these populations or prevent their extinction. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

Functionality‐fragility surfaces          下载免费PDF全文

Aman Karamlou  Paolo Bocchini 《地震工程与结构动力学》2017,46(10):1687-1709

The evaluation of functionality and its evolution in the aftermath of extreme events and during the restoration phase is a critical step in disaster resilience assessment. To this respect, this paper presents the ‘Functionality‐Fragility Surface’ (FFS), which is a tool for probabilistic functionality and resilience evaluation of damaged structures, infrastructure systems, and communities. FFS integrates two well‐known tools, namely Fragility Curves and Restoration Functions, to present the probability of loss of functionality of a system as a function of the extreme‐event intensity, as well as the elapsed time from the initiation of the restoration process. Because of their versatility, FFSs can be applied to components and systems belonging to different infrastructure sectors (e.g., transportation, power distribution, and telecommunication), so they provide a common rigorous paradigm for integrated resilience analyses of multiple sectors, as well as for studies on interdependencies within and across sectors. While it is shown that FFSs can be developed using available data and simple computations for different types of structures and infrastructure systems, this paper proposes also a sophisticated simulation‐based methodology to develop FFSs for individual bridges, taking into account the uncertainties involved in the response, damage, and restoration scheduling of bridges. A Multi‐Span Simply Supported Steel Girder bridge is used to showcase the application of the proposed methodology. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

三峡水库不同间距高程消落带草本植物群落物种多样性与结构特征   总被引：4，自引：1，他引：3  

雷波  王业春  由永飞  张晟  杨春华 《湖泊科学》2014,26(4):600-606

植物群落结构特征与其生境具有重要关系.三峡水库消落带独特的水文状况和不同地区地理条件的差异导致其不同区域不同水位高程的植被群落结构差异.为研究三峡水库消落带典型区域植被群落结构特征,调查分析了位于三峡水库腹地的消落带上、中、下部3个不同间距高程(145~155、155~170、170~175 m)的草本植物群落物种组成、生物多样性和结构特征.结果表明:共发现49种草本植物,上、中、下部分3个高程物种数分别为4、18、45种,随高程的增加物种数呈较为显著的增加;3个高程草本植物平均盖度、平均密度和平均高度范围分别为(2.58%±1.29%)74.83%±2.57%、(43.58±85.93)466.08±48.04株/m²和(4.89±0.56)77.02±9.31cm.综合分析表明,三峡水库腹地小范围流域消落带草本植物物种组成和结构趋于简单化,由于受水淹胁迫影响及不同高程微生境的差异,不同高程消落带植物多样性有所差异,呈现出的群落特征也有所不同,因此应充分考虑不同水位高程物种组成和结构的差异性特征,分类(区)配置物种搭配、优化种间关系可促进消落带草本植物多样性以及群落结构的改善.  相似文献