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81.
82.
The Role of Disaggregation of Asset Values in Flood Loss Estimation: A Comparison of Different Modeling Approaches at the Mulde River,Germany 总被引:3,自引:0,他引:3
Anja Wünsch Ulrich Herrmann Heidi Kreibich Annegret H. Thieken 《Environmental management》2009,44(3):524-541
In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure
data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary
information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual
influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this
paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC)
data. The resulting disaggregated assets are validated and compared using census data of the residential building number on
the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses
due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the
help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must,
however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements
compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution
LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling
aspects. 相似文献
83.
84.
Adaptive maritime spatial planning (MSP) uses monitoring and evaluation of the effectiveness of spatial and temporal management
measures to promote understanding and improve planning and decision-making. An adaptive approach to MSP involves exploring
alternative ways to meet management objectives, predicting the outcomes of alternative management measures, implementing one
or more of these alternative management measures, monitoring to learn about the effects of management measures, and then using
the results to update knowledge and adjust management actions. A monitoring and evaluation plan should be designed to be both
cost effective and comprehensive. The process of setting and assessing performance metrics requires that the ecological and
socio-economic objectives of the spatial management plan must be clearly stated up front for management actions to reflect
those objectives accurately. To evaluate the effectiveness of a MSP plan, a range of ecological, socio-economic and institutional
indicators need to be developed and monitored. 相似文献
85.
In this paper, we explore a range of concerns that arise in measuring short-term effects of ozone on health. In particular,
we tackle the problem of measuring exposure using alternative daily measures of ozone derived from hourly concentrations.
We adopt the exposure paradigm of Chiogna and Bellini (Environmetrics 13:55–69, 2002) extending it to ozone concentrations,
and we compare its performances with respect to traditional exposure measures by exploiting model selection. To investigate
the stability of model selection, we then apply the idea of bootstrapping the modelling process. 相似文献
86.
Salinity levels vary spatially in coastal areas, depending on proximity to freshwater sources, and may also be slowly decreasing
as a result of anthropogenic climatic changes. The impact of salinity on host–parasite interactions is potentially a key regulator
of transmission processes in intertidal areas, where trematodes are extremely common parasites of invertebrates and vertebrates.
We investigated experimentally the effects of long-term exposure to decreased salinity levels on output of infective stages
(cercariae) and their transmission success in the trematode Philophthalmus sp. This parasite uses the snail Zeacumantus subcarinatus as intermediate host, in which it asexually produces cercariae. After leaving the snail, cercariae encyst externally on hard
substrates to await accidental ingestion by shorebirds, which serve as definitive hosts. We found that at reduced salinities
(25 or 30 psu), the cercarial output of the parasite was lower, the time taken by cercariae to encyst was longer, fewer cercariae
successfully encysted and encysted parasites had lower long-term survival than at normal seawater salinity (35 psu). The strong
effect of salinity on the replication and transmission of this parasite suggests that there may be sources and sinks of transmission
to birds along coastal areas, depending on local salinity conditions. Also, unless it evolves to adapt to changing conditions,
the predicted reduction in salinity as a consequence of climate change may have negative impact on the parasite’s abundance. 相似文献
87.
Loss of zooxanthellae (dinoflagellate Symbiodinium) from corals will sometimes lead to mass mortality of corals. To detect and quantify Symbiodinium released from corals, we developed a zooxanthellae “trap” and a quantitative PCR (qPCR) system with Symbiodinium clades A–F-specific primer sets. The trap was attached to a branch or the surface of several wild stony corals, and the water
samples within the traps, including released Symbiodinium, were subjected to qPCR. All tested corals released clade C Symbiodinium at estimates of ~5,900 cells h−1 cm−2 of coral surface. Although all tested Pocillopora eydouxi harboured both clades C and D, some of these colonies released only clade C or released a lesser amount of clade D than that
in the tissues. Our Symbiodinium quantification system revealed that wild hermatypic corals constantly release Symbiodinium to the environment. Our result suggests that some corals may discharge certain clades of Symbiodinium alternatively. 相似文献
88.
89.
Urban greening increases vegetation and can restore ecological functions to urban systems. It has ties to restoration ecology, which aims to return degraded land to diverse, functional ecosystems. Both practices can be applied to maximizing ecosystem services and habitat in vacant lots, which are abundant in post-industrial cities, including Chicago, Illinois (USA), where our study took place. We tested four methods for increasing native plant diversity in vacant lots, ranging from low input to resource-intensive: seed bombing, broadcast seeding, planting plugs, and gardening. After three growing seasons, we assessed the growth of eight target native species and all non-target species. We expected that intensive treatments would have more target species stems and flowers and fewer non-target species, but we found that less-intensive options often produce equal or better results. From this, we recommend broadcast seeding as a viable, low-cost method for improving habitat and biodiversity in vacant lots.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01383-z) contains supplementary material, which is available to authorized users. 相似文献
90.
Chenxing Yang Xiaobo Lou Takahiro Matsui Junbo Zhang 《Mitigation and Adaptation Strategies for Global Change》2017,22(8):1149-1162
Global marine capture fisheries are undergoing serious stress, with overfishing as one of the major problems. In order to mitigate the overexploitation of capture fisheries, government regulation or fisheries management is necessary. Among various management approaches, vessel quantity control is being widely employed. To achieve effective governance of fisheries, the technical efficiency (TE) issue needs to be considered in the implementation of vessel quantity control. Using the Pacific saury (Cololabis saira) stick-held dip net fishery in Japan as a case study, this paper estimated the TE of sampled fishing vessels and explored the possible factors affecting the gap in efficiency. This paper aims to provide suggestions for a better implementation of vessel quantity control in global Pacific saury fishery, and also to serve as an empirical example of integrating TE analysis into management of overexploited fisheries for achieving satisfactory effects. Results show the TE score of the sampled fishery averaged around 0.7 from 2009 to 2014, and factors concerning owners/skippers’ motivation such as vessel ownership and specialization, vessel tonnage as well as skippers’ age show positive effects on the TE. Our findings in the present work provide important strategies for mitigating overexploitation in fisheries. Conducting technical efficiency analysis of targeted fisheries is a vital issue to be considered for designing and realizing an effective implementation of fisheries management approaches. The large vessels and the enthusiasm of vessel owners/skippers need to be particularly addressed when vessel quantity limit is considered to mitigate the problem of overfishing. 相似文献