Estimating the value of foresight: aggregate analysis of natural hazard mitigation benefits and costs

Hazard mitigation planners claim that foresighted present actions and investments produce significant future benefits. However, they have difficulty in supporting their claims, since previously their evidence typically was derived from individual case studies. Constituents and decision makers are often sceptical, believing that individual cases are either inapplicable to their situation or non-randomly selected to support a particular view. Planners need objective evidence based on a large body of experience to support the case for mitigation. Such is the unique contribution of a recent U.S. study that found that each dollar spent in three federal natural hazard mitigation grant programs (the Hazard Mitigation Grant Program, Project Impact, and the Flood Mitigation Assistance Program) saves society an average of $4 in future avoided losses. Complementing the aggregate benefit-cost analysis with community-based evaluations, the study yielded insights on how planners can improve long-term community resilience in the face of extreme events. Valuable lessons for mitigation planners and policy makers emerged: the need to consider a wide variety of losses, the importance of mixing qualitative with quantitative analysis, the value of averaging results over a large number of projects, and the need to more explicitly address social issues and data collection in order to reduce vulnerability and enhance resilience to cope with twenty-first century hazards.     

STORM DISCHARGE,LOADS, AND AVERAGE CONCENTRATIONS IN NORTHWEST OHIO RIVERS, 1975–19951

ABSTRACT: A computerized technique was developed to identify storm runoff episodes and calculate storm discharges, storm loads, and storm average concentrations for each event in datasets with up to 10,000 records. This technique was applied to four watersheds within the Lake Erie drainage basin and identified between 160 and 250 runoff events in each. Storm event loads and storm event mean concentrations were calculated for each runoff event for suspended solids, total phosphorus, soluble reactive phosphorus, nitrate, and total Kjeldahl nitrogen. The basic characteristics of the resulting data are described, as are systematic differences as a function of watershed size, seasonal differences, and trends over time. Many of the results of this study reflect the importance of nonpoint processes and improvements in agricultural best management practices in these watersheds.     

Assessment of Bioenergy Cropping Scenarios for the Boone River Watershed in North Central Iowa,United States

Several biofuel cropping scenarios were evaluated with an improved version of Soil and Water Assessment Tool (SWAT) as part of the CenUSA Bioenergy consortium for the Boone River Watershed (BRW), which drains about 2,370 km² in north central Iowa. The adoption of corn stover removal, switchgrass, and/or Miscanthus biofuel cropping systems was simulated to assess the impact of cellulosic biofuel production on pollutant losses. The stover removal results indicate removal of 20 or 50% of corn stover in the BRW would have negligible effects on streamflow and relatively minor or negligible effects on sediment and nutrient losses, even on higher sloped cropland. Complete cropland conversion into switchgrass or Miscanthus, resulted in reductions of streamflow, sediment, nitrate, and other pollutants ranging between 23‐99%. The predicted nitrate reductions due to Miscanthus adoption were over two times greater compared to switchgrass, with the largest impacts occurring for tile‐drained cropland. Targeting of switchgrass or Miscanthus on cropland ≥2% slope or ≥7% slope revealed a disproportionate amount of sediment and sediment‐bound nutrient reductions could be obtained by protecting these relatively small areas of higher sloped cropland. Overall, the results indicate that all biofuel cropping systems could be effectively implemented in the BRW, with the most robust approach being corn stover removal adopted on tile‐drained cropland in combination with a perennial biofuel crop on higher sloped landscapes. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.     

Examination of the bioaccumulation of halogenated dimethyl bipyrroles in an Arctic marine food web using stable nitrogen isotope analysis.

Concentrations of four possibly naturally produced organohalogens--1,1'-dimethyl-3,3',4-tribromo-4,5,5'-trichloro-2,2'-bipyrrole (DBP-Br3Cl3), 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole (DBP-Br4Cl2), 1,1'-dimethyl-3,3',4,4',5-pentabromo-5'-chloro-2,2'-bipyrrole (DBP-Br5Cl) and 1,1'-dimethyl-3,3',4,4',5,5'-hexabromo-2,2'-bipyrrole (DBP-Br6)--were quantitated and the extent of their magnification through an entire Arctic marine food web [measured as integrated trophic magnification factors (TMFs)] were calculated. The food web consisted of three zooplankton species (Calanus hyperboreus, Mysis oculata, and Sagitta sp.), one fish species [Arctic cod (Boreogadus saida)], four seabird species [dovekie (Alle alle), black guillemot (Cepphus grylle), black-legged kittiwake (Rissa tridactyla), and glaucous gull (Larus hyperboreus)], and one marine mammal species [ringed seal (Phoca hispida)]. Trophic levels in the food web were calculated from ratios of stable isotopes of nitrogen (15N/14N). All halogenated dimethyl bipyrrole (HDBP) congeners were found to significantly (P<0.02) biomagnify, or increase in concentration with trophic level in the invertebrate--fish--seabird food web. DBP-Br4Cl2 (TMF= 14.6) was found to biomagnify to a greater extent than DBP-Br3Cl3 (TMF = 5.2), DBP-Br5Cl (TMF = 6.9), or DBP-Br6 (TMF = 7.0), even though the Kow of DBP-Br4CI2 was predicted to be lower than those of DBP-Br5Cl and DBP-Br6. None of the four HDBP congeners in ringed seals followed the general trend of increasing concentration with trophic level, which was possibly due to an ability of the seals to metabolize HDBPs.     

FARM-LEVEL MANAGEMENT OF DEEP PERCOLATION EMISSIONS IN IRRIGATED AGRICULTURE1

ABSTRACT: Source control costs for deep percolation emissions from irrigated agriculture are analyzed using a farm-level model. Crop area, irrigation system and applied water are chosen to maximize the net benefits of agricultural production while accounting for the environmental damages and disposal costs of those emissions. Deep percolation is progressively reduced as environmental and disposal costs are increased. This occurs primarily through the adoption of more efficient irrigation technology and reductions in applied water for a given technology Higher surface water prices, such as through irrigation reform and constrained surface supplies, are additionally considered in light of the drainage problem, as are the effects, both short- and long-term, on ground water use.     

Regulation of pesticide discharge into surface and groundwater under uncertainty: A model for environmental risk‐profitability tradeoffs and policy selection

The presence of contaminants in environmental media as well as the desire to maintain a high level of economic activity has led to an important and difficult decision‐making problem for both public policy decision makers and the general public. In one sense, all of the interested parties are likely to be concerned about the potential health risks posed by the presence of contaminants in environmental media and the need to design/implement policies for their mitigation and/or removal. At the same time, however, there also appear to be concerns about the cost of these policies. These costs could be measured in terms of the potential losses in economic activity that are likely to occur when a policy is adopted. The policy can be selected from a range of alternatives, with the choice being driven in part by the stakeholders represented in the policy decision problem. In this case, two general goals might be considered: minimizing environmental risk and minimizing the economic impact of the policy considered. These two objectives are likely to be viewed as conflicting goals, and the nature of the tradeoffs between them must be taken into account in the policy selection process. This paper presents the development of a zero–one weighted goal programming model that can be used to select a preferred policy that minimizes surface and groundwater contamination as well as the economic costs of environmental policy selection. A safety rule model is developed first and then extended to the zero–one weighted goal programming formulation. The stochastic aspects of these structures are emphasized throughout. The paper also addresses a number of issues related to implementation of the model.     

Resolving future fire management conflicts using multicriteria decision making

Management strategies to reduce the risks to human life and property from wildfire commonly involve burning native vegetation. However, planned burning can conflict with other societal objectives such as human health and biodiversity conservation. These conflicts are likely to intensify as fire regimes change under future climates and as growing human populations encroach farther into fire‐prone ecosystems. Decisions about managing fire risks are therefore complex and warrant more sophisticated approaches than are typically used. We applied a multicriteria decision making approach (MCDA) with the potential to improve fire management outcomes to the case of a highly populated, biodiverse, and flammable wildland–urban interface. We considered the effects of 22 planned burning options on 8 objectives: house protection, maximizing water quality, minimizing carbon emissions and impacts on human health, and minimizing declines of 5 distinct species types. The MCDA identified a small number of management options (burning forest adjacent to houses) that performed well for most objectives, but not for one species type (arboreal mammal) or for water quality. Although MCDA made the conflict between objectives explicit, resolution of the problem depended on the weighting assigned to each objective. Additive weighting of criteria traded off the arboreal mammal and water quality objectives for other objectives. Multiplicative weighting identified scenarios that avoided poor outcomes for any objective, which is important for avoiding potentially irreversible biodiversity losses. To distinguish reliably among management options, future work should focus on reducing uncertainty in outcomes across a range of objectives. Considering management actions that have more predictable outcomes than landscape fuel management will be important. We found that, where data were adequate, an MCDA can support decision making in the complex and often conflicted area of fire management.     

Considering extinction of dependent species during translocation, ex situ conservation, and assisted migration of threatened hosts

Translocation, introduction, reintroduction, and assisted migrations are species conservation strategies that are attracting increasing attention, especially in the face of climate change. However, preventing the extinction of the suite of dependent species whose host species are threatened is seldom considered, and the effects on dependent species of moving threatened hosts are unclear. There is no published guidance on how to decide whether to move species, given this uncertainty. We examined the dependent-host system of 4 disparate taxonomic groups: insects on the feather-leaf banksia (Banksia brownii), montane banksia (B. montana), and Stirling Range beard heath (Leucopogon gnaphalioides); parasites of wild cats; mites and ticks on Duvaucel's gecko (Hoplodactylus duvaucelii) and tuatara (Sphenodon punctatus); and internal coccidian parasites of Cirl Bunting (Emberiza cirlus) and Hihi (Notiomystis cincta). We used these case studies to demonstrate a simple process for use in species- and community-level assessments of efforts to conserve dependents with their hosts. The insects dependent on Stirling Range beard heath and parasites on tigers (Panthera tigris) appeared to represent assemblages that would not be conserved by ex situ host conservation. In contrast, for the cases of dependent species we examined involving a single dependent species (internal parasites of birds and the mite Geckobia naultina on Duvaucel's gecko), ex situ conservation of the host species would also conserve the dependent species. However, moving dependent species with their hosts may be insufficient to maintain viable populations of the dependent species, and additional conservation strategies such as supplementing populations may be needed.