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《Journal of Great Lakes research》2021,47(6):1613-1625
Climate change has the potential to alter the physical and chemical properties of water in the Great Lakes Basin, in turn impacting ecological function. This study synthesizes existing research associated with the potential effects of a changing climate on the quality and quantity of groundwater in the Great Lakes Basin. It includes analyses of impacts on (1) recharge, (2) groundwater storage, (3) discharge and groundwater-surface water (GW-SW) interactions, (4) exacerbating future urban development impacts on groundwater, (5) groundwater quality, and (6) ecohydrology.Large spatial and temporal (i.e., seasonal) variability in groundwater response to climate change between regions is anticipated. Most studies combine field observations with modelling, but many have focused only on small/medium basins. At these small scales, groundwater systems are generally projected to be fairly resilient to climate change impacts. However, modelling studies of larger basins (e.g., Grand River, Saginaw Bay, Maumee River) predict an increase in groundwater storage. Uncertainty in model simulations, particularly from climate models that are used to force hydrological models, is a major challenge. There have been too few studies to date that investigate the interplay of climate change and groundwater quality in the Great Lakes Basin to draw conclusions about future groundwater quality and ecohydrology.A summary of methods, models, and technology is provided. Model uncertainty has become an increasingly important topic and is also discussed. The study concludes with a synthesis of the main science needs to understand groundwater impacts in order to adapt to a changing climate in the Great Lakes Basin. 相似文献
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《Journal of Great Lakes research》2020,46(6):1661-1673
Tributaries provide spawning habitat for three of four major sub-stocks of Lake Erie walleye (Sander vitreus). Despite anthropogenic degradation and the extirpation of other potamodromous species, the Maumee River, Ohio, USA continues to support one of the largest fish migrations in the Laurentian Great Lakes. To determine if spawning habitat availability and quality could limit production of Maumee River walleye, two habitat suitability models were created for the lower 51 km of the Maumee River and the distribution and numbers of walleye eggs deposited in a 25 km stretch of river were assessed. Walleye eggs were collected using a diaphragm pump at 7 and 10 sites from March/April to May 2014 and 2015. The habitat suitability models showed that <3% of the river yielded ‘good’ walleye spawning habitat and 11–38% yielded ‘moderate’ walleye spawning habitat, depending on the model. However, a large set of rapids at river kilometer 28 and more than five river kilometers of less suitable habitat separated areas of ‘good’ habitat. The rapids may present a migratory barrier for many spawning walleye, as modeled water velocities exceed maximum estimated walleye swim speeds 71–100% of days during pre-spawn migration and spawning during the study period. In both study years, there was a sharp decline in mean egg numbers from spawning sites downstream of the rapids (439.7 eggs/2 min tow ± 990.6 SD) to upstream sites (5.9 eggs/2 min tow ± 19.4 SD). Physical barriers like rapids may reduce spawning habitat connectivity and could limit walleye production in the Maumee River. 相似文献
87.
Policy implications of a pan-tropic assessment of the simultaneous hydrological and biodiversity impacts of deforestation 总被引:2,自引:0,他引:2
Ellen M. Douglas Stanley Wood Kate Sebastian Charles J. Vörösmarty Kenneth M. Chomitz Thomas P. Tomich 《Water Resources Management》2007,21(1):211-232
Tropical deforestation has many consequences, amongst which alteration of the hydrological cycle and loss of habitat and biodiversity
are the focus of much public interest and scientific research. Here we examine the potential biodiversity and hydrological
impacts of an extreme deforestation scenario – the loss of all tropical forest areas currently identified by the World Wildlife
Fund as being threatened. Existing tropical forest areas are first classified according to two categories of biological distinctiveness
– high and low – using indicators developed by the WWF. We apply the tropical deforestation scenario to a macro-scale hydrologic
model, keeping track of the share of change in basin runoff that originates from the deforestation of areas of high versus
low biological distinctiveness and where that change could impact human populations. Of particular interest are those basins
where loss of the most threatened tropical forest areas would give rise to significant biodiversity loss and to potentially large hydrological impacts. In such cases it is conceivable that biodiversity conservation could “free-ride”
on the concerns of resident populations to maintain the forests for the purpose of minimizing hydrological change. Where such
an outcome seems likely, biodiversity conservation efforts might be better targeted elsewhere, perhaps to basins where the
loss of forest areas with high biological distinctiveness would have less population impacts, hence requiring an alliance
between biological and hydrological interests to gain sufficient social and financial support for conservation. 相似文献
88.
根据长江治理、开发和保护所面临的新形势、新任务、新要求,提出在《中华人民共和国水文条例》颁布实施条件下,长江水文适应“维护健康长江,促进人水和谐”宗旨的基本要求,探讨了流域水文科技进步、站网优化和与地方水文协作发展的思路。 相似文献
89.
设计洪水是确定河流治理方案和开发水利水电工程规模的重要基础数据,其成果的可靠与否直接关系到工程的规模和工程的安全性。阳河干流大菜园水文站的实测资料系列在进行一致性处理后刚好满足《水利水电工程设计洪水计算规范》(SL 44-2006)关于资料系列不少于30年的要求,但因其上游上已建成3座水库(总调洪库容5 900万m3)削峰作用较大,故对该站洪水系列进行了插补延长,对历史洪水重现期作了考证,对不同系列的设计洪水成果作了分析比较,并提出了较合理的设计洪水成果。通过这些工作,说明了资料“三性(可靠性、一致性、代表性)”分析的重要性,尤其说明了即使测站具有30年资料系列,其代表性仍可能有不足这一现象,建议在工程设计中应尽可能地延长资料系列以提高系列的代表性,不能仅局限于满足30年资料系列即可。 相似文献
90.
James H. Larson Anett S. Trebitz Alan D. Steinman Michael J. Wiley Martha Carlson Mazur Victoria Pebbles Heather A. Braun Paul W. Seelbach 《Journal of Great Lakes research》2013
At the interface of the Great Lakes and their tributary rivers lies the rivermouths, a class of aquatic ecosystem where lake and lotic processes mix and distinct features emerge. Many rivermouths are the focal point of both human interaction with the Great Lakes and human impacts to the lakes; many cities, ports, and beaches are located in rivermouth ecosystems, and these human pressures often degrade key ecological functions that rivermouths provide. Despite their ecological uniqueness and apparent economic importance, there has been relatively little research on these ecosystems as a class relative to studies on upstream rivers or the open-lake waters. Here we present a synthesis of current knowledge about ecosystem structure and function in Great Lakes rivermouths based on studies in both Laurentian rivermouths, coastal wetlands, and marine estuarine systems. A conceptual model is presented that establishes a common semantic framework for discussing the characteristic spatial features of rivermouths. This model then is used to conceptually link ecosystem structure and function to ecological services provided by rivermouths. This synthesis helps identify the critical gaps in understanding rivermouth ecology. Specifically, additional information is needed on how rivermouths collectively influence the Great Lakes ecosystem, how human alterations influence rivermouth functions, and how ecosystem services provided by rivermouths can be managed to benefit the surrounding socioeconomic networks. 相似文献