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1.
Intertemporal trade-offs are ubiquitous in environmental decision-making and policy, yet comprehensive, practical guides are lacking. This paper introduces an adaptive, iterative approach to environmental policy, combining the insights of economics, psychology, and anthropology. We first summarize the major paradigms of each discipline, including models, concepts of time preference, strengths, and blind spots. Subsequently, we illustrate the integrative approach through four real-world environmental examples: a shopper purchasing a light bulb, an organization doing building renovations, a community considering a new source of renewable energy, and international organizations developing index insurance for farmers in the Horn of Africa. One-dimensional approaches are ill-suited to real-world challenges such as these, because each discipline only tackles one facet of the issue. In contrast, with each discipline informing the others, the integrative approach is more than the sum of its parts. This paper provides a concise guide for applied researchers and policy makers alike.  相似文献   
2.
The article explains Iraq's precipitous decline into food insecurity following its military invasion of Kuwait. Food security and insecurity are defined and then examined in the Iraqi context. Five vulnerabilities are identified that were activated by international retaliation against Iraq, including the UN Security Council's embargo on trade between Iraq and the rest of the world and the Gulf War itself. The emergence and intensification of food insecurity are analyzed step by step, followed by consideration of how food security might be restored in Iraq. An Appendix assesses whether Iraq experienced famine in 1991.  相似文献   
3.
Proxy-based climate reconstructions can extend instrumental records by hundreds of years, providing a wealth of climate information at high temporal resolution. To date, however, their usefulness for informing climate risk and variability in policy and social applications has been understudied. Here, we apply tree-ring based reconstructions of drought for the last 700 years in a climate index insurance framework to show that additional information from long climate reconstructions significantly improves our understanding of the underlying climate distributions and variability. We further show that this added information can be used to better characterize risk to insurance providers, in many cases providing meaningful reductions in long-term contract costs to farmers in stand-alone policies. The impact of uncertainty on insurance premiums can also be reduced when insurers diversify portfolios, and the availability of long-term climate information from tree rings across a broad geographic range provides an opportunity to characterize spatial correlation in climate risk across geographic regions. Our results are robust to the range of climate variability experienced over the last 400 years and in model simulations of the twenty-first century, even within the context of changing baselines due to low frequency variability and secular climate trends. These results demonstrate the utility of longer-term climate histories in index insurance applications. Furthermore, they make the case from a climate-variability perspective for the continued importance of such approaches to improving the instrumental climate record, even into a non-stationary climate future.  相似文献   
4.
Benthic macroinvertebrate abundance, taxonomic composition, and surface flooding dynamics were compared among high and low elevation stands of narrow-leaved cattail (Typha angustifolia) and invasive common reed (Phragmites australis) at Iona Island Marsh, an oligohaline wetland, and Piermont Marsh, a mesohaline wetland, within the Hudson River National Estuarine Research Reserve during 1999 and 2000. Overall, the benthic macroinvertebrate community at both sites was similar in composition and abundance to those documented from other low-salinity systems. Macroinvertebrate taxa richness was lowest in mesohaline common reed, but similar among common reed and cattail habitats in oligohaline wetlands. Total macroinvertebrate densities were greater at high-elevation compared to low-elevation reed stands at the mesohaline site during summer 1999 and spring 2000. Total macroinvertebrate densities were similar among both oligohaline vegetation types during all seasons, except for spring 2000, when lower densities were observed in low-elevation common reed. A weak positive relationship between macroinvertebrate density and depth of flooding suggests that surface hydrology may be influencing the observed patterns of macroinvertebrate density among the vegetation stands. These results suggest that benthic macroinvertebrate abundance and diversity may not necessarily be impaired in low-salinity wetlands experiencing invasion by common reed unless the change in vegetation is accompanied by a measurable alteration to physical conditions on the marsh surface (i.e., elevation and flooding dynamics).  相似文献   
5.
6.
Through their physiological effects on ion, oxygen, and carbon balance, respectively, salinity, sulfide, and prolonged flooding combine to constrain the invasion and spread ofPhragmites in tidal wetlands. Initial sites of vigorous invasion by seed germination and growth from rhizome fragments appear limited to sections of marsh where salinity is <10‰, sulfide concentrations are less than 0.1 mM, and flooding frequency is less than 10%. In polyhaline tidal wetlands the invasion sites include the upland fringe and some high marsh creek banks. The zones of potential invasion tend to be larger in marshes occupying lower-salinity portions of estuaries and in marshes that have been altered hydrologically. Owing to clonal integration and a positive feedback loop of growth-induced modification of edaphic soil conditions, however, a greater total area of wetland is susceptible toPhragmites expansion away from sites of establishment. Mature clones have been reported growing in different marshes with salinity up to 45‰, sulfide concentration up to 1.75 mM, and flooding frequency up to 100%. ForPhragmites establishment and expansion in tidal marshes, windows of opportunity open with microtopographic enhancement of subsurface drainage patterns, marsh-wide depression of flooding and salinity regimes, and variation in sea level driven by global warming and lunar nodal cycles. To avoidPhragmites monocultures, tidal wetland creation, restoration, and management must be considered within the context of these different scales of plant-environment interaction.  相似文献   
7.
Field Data and Ground Water Modeling in a Layered Fractured Aquifer   总被引:5,自引:0,他引:5  
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8.
ABSTRACT

The grounding of the MV Rena in 2011 necessitated urgent entry of salvage vessels into New Zealand. Two, a cargo barge and tug, had been idle in Australia before mobilisation and had well-developed biofouling assemblages that included non-indigenous species new to New Zealand. Surveillance for the species was initiated in Tauranga harbour, Astrolabe Reef and Mōtītī Island, where the vessels had operated. Response personnel were trained to recognise and report the organisms and active surveys were implemented, including reinspection of the vessels after treatment of the biofouling, dive and shoreline searches, and trapping. Although none of the risk species was detected, the biosecurity risk from the vessels changed during the response, from initially acting as a vector for species new to New Zealand to later transporting non-indigenous species from coastal ports to the arena of operations. The study highlights a need for better integration of biosecurity risk management into forward planning for maritime incidents.  相似文献   
9.
This paper presents three baseline scenarios of no policy action computed by the IMAGE 2 model. These scenarios cover a wide range of coupled global change Indicators, including: energy demand and consumption; food demand, consumption, and production; changes in land cover including changes in extent of agricultural land and forest; emissions of greenhouse gases and ozone precursors; and climate change and its impacts on sea level rise, crop productivity and natural vegetation. Scenario information is available for the entire world with regional and grid scale detail, and covers from 1970 to 2100. The scenarios indicate that the coming decades could be a period of relatively rapid global environmental change as compared to the period before and after. The natural vegetation in industrialized regions could be threatened by climate change, but abandonment of agricultural lands could also make new lands available for reforestation and revegetation. The opposite is true for most of Asia and Africa. Here the impacts of climate change on vegetation may not be as significant as in temperate climates, but the demand for food will lead to a significant expansion of agricultural lands at the expense of remaining forests and other natural areas.  相似文献   
10.
Conservation surrogates, such as umbrella and flagship species, could help focus South Africa’s limited resources for research and management and enhance the conservation gains from marine protected areas (MPAs). Sharks, rays and chimaeras (Chondrichthyes), which are charismatic and ecologically diverse, are potential umbrella candidates, but tests of the ecological suitability of putative marine umbrella species are lacking. Using baited remote underwater video in and around two MPAs in the Western Cape Province, we assessed the potential of chondrichthyans as an umbrella species-complex by quantifying the relationships and co-occurrence patterns between chondrichthyan abundance and diversity and those of other taxa (primarily teleosts and crustaceans). Sites with abundant chondrichthyans, with catsharks or large sharks (>1 m total length), all had significantly greater abundance and diversity of these other taxa, and associations with species of commercial and conservation interest (e.g. roman Chrysoblephus laticeps). Endemic scyliorhinids (notably dark catshark Haploblepharus pictus) and the broadnose sevengill shark Notorynchus cepedianus also had many strong positive co-occurrences (28% and 21% of interactions, respectively). The puffadder catshark H. edwardsii had the highest centrality of any species, denoting its high connectedness to other taxa. Overall, chondrichthyans, especially the dark and puffadder catsharks and the broadnose sevengill shark, show strong potential as an umbrella species-complex in South Africa.  相似文献   
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