Is Eating Locally a Moral Obligation?

Advocates of eating locally offer a wide range of arguments in favor of the practice, but their ethical import is not always clear. Some locavore statements and arguments seem to imply a strong form of moral obligation; that eating locally is not merely instrumental to some other good, but has intrinsic value in its own right. This article examines standard arguments on behalf of eating locally, including arguments linked to the value of small farms and agrarianism, the environment, taste and health, trust, and relational markets. Most arguments put forward on behalf of eating locally value it instrumentally, the main exception being arguments based on relational markets. Although these arguments provide important motives for eating locally, the strength of obligation varies widely, and even the strongest arguments possess significant qualifications. While eating locally can play a role in reducing environmental impacts, this is not necessarily so, and once removed from instrumental considerations, eating locally is more likely at best an imperfect duty.     

Predicting breeding habitat for amphibians: a spatiotemporal analysis across Yellowstone National Park

The ability to predict amphibian breeding across landscapes is important for informing land management decisions and helping biologists better understand and remediate factors contributing to declines in amphibian populations. We built geospatial models of likely breeding habitats for each of four amphibian species that breed in Yellowstone National Park (YNP). We used field data collected in 2000-2002 from 497 sites among 16 basins and predictor variables from geospatial models produced from remotely sensed data (e.g., digital elevation model, complex topographic index, landform data, wetland probability, and vegetative cover). Except for 31 sites in one basin that were surveyed in both 2000 and 2002, all sites were surveyed once. We used polytomous regression to build statistical models for each species of amphibian from (1) field survey site data only, (2) field data combined with data from geospatial models, and (3) data from geospatial models only. Based on measures of receiver operating characteristic (ROC) scores, models of the second type best explained likely breeding habitat because they contained the most information (ROC values ranged from 0.70 to 0.88). However, models of the third type could be applied to the entire YNP landscape and produced maps that could be verified with reserve field data. Accuracy rates for models built for single years were highly variable, ranging from 0.30 to 0.78. Accuracy rates for models built with data combined from multiple years were higher and less variable, ranging from 0.60 to 0.80. Combining results from the geospatial multiyear models yielded maps of "core" breeding areas (areas with high probability values for all three years) surrounded by areas that scored high for only one or two years, providing an estimate of variability among years. Such information can highlight landscape options for amphibian conservation. For example, our models identify alternative areas that could be protected for each species, including 6828-10 764 ha for tiger salamanders, 971-3017 ha for western toads, 4732-16 696 ha for boreal chorus frogs, and 4940-19 690 ha for Columbia spotted frogs.     

Calculating the aquatic toxicity of hydrocarbon mixtures

For acute toxicity to aquatic organisms, individual hydrocarbons are equally toxic on the basis of their internal molar concentration within the organism. The differences in measured toxicities among hydrocarbons lies with differences in their equilibrium partitioning behavior between water and the organism. For complex hydrocarbon mixtures, an additional complication of partitioning between the bulk hydrocarbon and the water is encountered. Equations are developed for calculating the water concentration of components of complex hydrocarbon mixtures. Using gasoline as an example, a method is presented for first calculating the concentration of gasoline components in water after equilibration with different gasoline volumes and then, the component toxicities are used to estimate the gasoline volume causing 50% mortality to aquatic organisms.     

Land cover changes reduce net primary production in tropical coastal peatlands of West Kalimantan,Indonesia

Mitigation and Adaptation Strategies for Global Change - Tropical peat swamp forests are carbon-rich ecosystems that have been threatened by high rates of land use change (LUC). Despite the...     

Comparisons in demographic rates of bay scallops in eelgrass and the introduced alga, Codium fragile, in New York

Bay scallops, Argopecten irradians, supported vibrant fisheries which subsequently collapsed, as such, they are a focus species for many restoration efforts along the Atlantic and Gulf coasts of the United States. The scallops’ preferred habitat, seagrass, has also dramatically declined, and some scallop populations have increased post-restoration despite reduced seagrass cover. This has led to the hypothesis that macroalgae may serve as suitable alternative habitats for bay scallops. This study is the first to compare demographic rates, such as long-term survival, growth, condition and reproductive potential of scallops between the native eelgrass, Zostera marina, and the introduced alga, Codium fragile. Although long-term survival was not different between habitats, results suggest site-specific and inter-annual variation in the impacts of Codium on scallop growth. While demographic rates did not differ in Shinnecock Bay, in Sag Harbor, growth and/or condition were significantly different between both vegetated habitats depending on the year. However, recruit density, size and condition did not vary significantly, adding to the complexity of this relationship. Despite potential site-specific and inter-annual differences, this study supports the hypothesis that habitats other than eelgrass can benefit bay scallops.     

Effects of seawater temperature and pH on the boring rates of the sponge Cliona celata in scallop shells

Warmer, more acidic water resulting from greenhouse gas emissions could influence ecosystem processes like bioerosion of calcifying organisms. Based on summer-maxima values (temperature = 26 °C; pH = 8.1) at a collection site in New York (40°56″ N, 72°30″ W), explants of the boring sponge Cliona celata Grant, 1826 were grown for 133 days on scallop shells in seawater ranging from current values to one scenario predicted for the year 2100 (T = 31 °C; pH = 7.8). High water temperature had little effect on sponge growth, survival, or boring rates. Lower pH slightly reduced sponge survival, while greatly influencing shell boring. At pH = 7.8, sponges bored twice the number of papillar holes and removed two times more shell weight than at pH = 8.1. Greater erosion resulted in weaker scallop shells. This study suggests that lower seawater pH may increase boring rates of C. celata in shellfish, with potentially severe implications for wild and farmed shellfish populations.     

Uses and misuses of bioclimatic envelope modeling

Bioclimatic envelope models use associations between aspects of climate and species' occurrences to estimate the conditions that are suitable to maintain viable populations. Once bioclimatic envelopes are characterized, they can be applied to a variety of questions in ecology, evolution, and conservation. However, some have questioned the usefulness of these models, because they may be based on implausible assumptions or may be contradicted by empirical evidence. We review these areas of contention, and suggest that criticism has often been misplaced, resulting from confusion between what the models actually deliver and what users wish that they would express. Although improvements in data and methods will have some effect, the usefulness of these models is contingent on their appropriate use, and they will improve mainly via better awareness of their conceptual basis, strengths, and limitations.