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Xie Xiaoliang Zuo Jinxia Xie Bingqi Dooling Thomas A. Mohanarajah Selvarajah 《Natural Hazards》2021,107(3):2555-2572
Natural Hazards - From a macro-perspective, based on machine learning and data-driven approach, this paper utilizes multi-featured data from 31 provinces and regions in China to build a Bayesian... 相似文献
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Natural Hazards - Cyclones endanger life and cause great financial impact on interior and coastal regions through the destruction of buildings and land. Governments need to have a way of estimating... 相似文献
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The impact of ditch blocking on the hydrological functioning of blanket peatlands 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Joseph Holden Sophie M. Green Andy J. Baird Richard P. Grayson Gemma P. Dooling Pippa J. Chapman Christopher D. Evans Mike Peacock Graeme Swindles 《水文研究》2017,31(3):525-539
Ditch blocking in blanket peatlands is common as part of peatland restoration. The effects of ditch blocking on flow regimes and nearby water tables were examined in a field trial. After an initial 6‐month monitoring period, eight ditches had peat dams installed 10 m apart along their entire length (dammed), four of these ditches were also partially infilled through bank reprofiling (reprofiled). Four ditches were left open with no dams or reprofiling (open). These 12 ditches and the surrounding peat were monitored for 4 more years. An initial five‐fold reduction in discharge occurred in the dammed and the reprofiled ditches with the displaced water being diverted to overland flow and pathways away from the ditches. However, there was a gradual change over time in ditch flow regime in subsequent years, with the overall volume of water leaving the dammed and the reprofiled ditches increasing per unit of rainfall to around twice that which occurred in the first year after blocking. Hence, monitoring for greater than one year is important for understanding hydrological impacts of peatland restoration. Overland flow and flow in the upper ~4 cm of peat was common and occurred in the inter‐ditch areas for over half of the time after ditch blocking. There was strong evidence that topographic boundaries of small ditch catchments, despite being defined using a high‐resolution Light Detection And Ranging‐based terrain model, were not always equivalent to actual catchment areas. Hence, caution is needed when upscaling area‐based fluxes, such as aquatic carbon fluxes, from smaller scale studies including those using ditches and small streams. The effect of ditch blocking on local water tables was spatially highly variable but small overall (time‐weighted mean effect <2 cm). Practitioners seeking to raise water tables through peatland restoration should first be informed either by prior measurement of water tables or by spatial modelling to show whether the peatland already has shallow water tables or whether there are locations that could potentially undergo large water‐table recoveries. 相似文献
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Joseph Holden Catherine S. Moody T. Edward Turner Rebecca McKenzie Andy J. Baird Mike F. Billett Pippa J. Chapman Kerry J. Dinsmore Richard P. Grayson Roxane Andersen Clare Gee Gemma Dooling 《水文研究》2018,32(4):550-561
Perennial pools are common natural features of peatlands, and their hydrological functioning and turnover may be important for carbon fluxes, aquatic ecology, and downstream water quality. Peatland restoration methods such as ditch blocking result in many new pools. However, little is known about the hydrological function of either pool type. We monitored six natural and six artificial pools on a Scottish blanket peatland. Pool water levels were more variable in all seasons in artificial pools having greater water level increases and faster recession responses to storms than natural pools. Pools overflowed by a median of 9 and 54 times pool volume per year for natural and artificial pools, respectively, but this varied widely because some large pools had small upslope catchments and vice versa. Mean peat water‐table depths were similar between natural and artificial pool sites but much more variable over time at the artificial pool site, possibly due to a lower bulk specific yield across this site. Pool levels and pool‐level fluctuations were not the same as those of local water tables in the adjacent peat. Pool‐level time series were much smoother, with more damped rainfall or recession responses than those for peat water tables. There were strong hydraulic gradients between the peat and pools, with absolute water tables often being 20–30 cm higher or lower than water levels in pools only 1–4 m away. However, as peat hydraulic conductivity was very low (median of 1.5 × 10?5 and 1.4 × 10?6 cm s?1 at 30 and 50 cm depths at the natural pool site), there was little deep subsurface flow interaction. We conclude that (a) for peat restoration projects, a larger total pool surface area is likely to result in smaller flood peaks downstream, at least during summer months, because peatland bulk specific yield will be greater; and (b) surface and near‐surface connectivity during storm events and topographic context, rather than pool size alone, must be taken into account in future peatland pool and stream chemistry studies. 相似文献
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This paper seeks to clarify and refine the assertion that vulnerability exists as both a material, condition and discursive construct. Building off of previous scholarship analyzing the production of, vulnerabilities, we present a conceptual framework that illuminates how material vulnerabilities are translated into political vulnerabilities and ossified in the policy realm. We argue that specifying components of, and relationships between, the material and political aspects of vulnerability will result in a more sophisticated articulation of vulnerability as a recursive process. In order to achieve this level of analysis we propose a spatial–historical analytic approach that blends point-in-time and, empirically driven analysis with robust historical and political economic analysis. We use the largest urban wildfire – in terms of dwellings lost – in California's history to show how the persistent disconnection between material and political forms of vulnerability has, over time, resulted in contradictory landscapes where homes are intentionally placed in landscapes vulnerable to wildfires with reduced fire protection. Spatial historical analysis of the Tunnel Fire reveals how representations of vulnerability oftentimes deviate from lived experiences, engendering responses of exploitation, ignorance, mobilization and resistance. This framework also recognizes how these responses can create new vulnerabilities while also maintaining, deepening and diminishing existing material conditions. Finally, relational analysis illuminates how factors generating vulnerability in fire areas also contribute to and reinforce vulnerabilities within other parts of cities like Oakland, California. 相似文献
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