Constructing Interpretable Environments from Multidimensional Data: GIS Suitability Overlays and Principal Component Analysis

In landscape planning applications, practitioners and governmental agencies are often faced with a broad array of clientele and constituents having particular land use requirements and needs, ranging from biological conservation to urban development, generating complex multidimensional regional planning goals and objectives. Under this often complex situation, investigators are searching for methods to intelligently simplify complicated spatial environments and render them into interpretable and practical settings. While numerous investigators have studied the generation of a single suitability map, we were interested in addressing the problem of coping with a set of many suitability maps. We applied a data reduction method, principal component analysis, across 15 suitability overlays representing diverse landscape requirements to search for simplified explanations indicating the latent structure of the landscape. The study area was located in a moraine landscape of southern Michigan. We discovered that the 15 suitability overlays could be reduced to seven dimensions, containing 65% of the original data structure and that the seven dimensions reflect a structure where a variety of land uses each have their own optimal spatial locations, indicating low to moderate competition between potentially conflicting land uses and rendering a more easily understood environment. This approach did not render a simple elegant solution but it did reduce the complexity associated with combining many suitability maps.     

Polychlorinated dibenzofuran (PCDF) and dibenzo-p-dioxin (PCDD) levels in organisms and sediments from the frierfjord, southern Norway

The contamination of a fjord region by PCDD and PCDF produced from a Mg-production plant has been studied. Levels in organisms (fish, crustacea, mussels) and sediments were determined. The results allowed an estimate of the spreading of PCDD/PCDF by coastal currents. The present situation is compared with available information from other contaminated areas and with data for other contaminants in the recipient area such as hexachlorobenzene and octachlorostyrene.     

PCDDs and PCDFs in human adipose tissue from the EPA FY82 NHATS repository

Analysis for tetra- through octachloro-PCDDs and PCDFs was completed for 46 tissue samples prepared from the U.S. Environmental Protection Agency (EPA) National Human Adipose Tissue Survey (NHATS). The samples were prepared as composites from over 900 specimens to represent the nine U.S. census divisions and three age groups (0–14, 15–44, and 45 plus years). The data demonstrate that PCDDs and PCDFs are prevalent in the general U.S. population and that differences exist with age.     

Common access tradition and wilderness management in Norway: A paradox for managers

Many European countries, including Norway, have a right of common access tradition toward wildland areas for recreational activity. The “right of any one to move freely over all wildlands except farm fields and gardens” can serve as a paradoxical barrier to managing wildland areas and users for outdoor recreation. This article discusses the apparent paradox between free access and management of wildland recreation, the underlying principles of both concepts, and proposes an integrative basis for how the two concepts can serve the same major goal—freedom of access and use of wildland recreation areas without disturbance to other users or the resource base. A Norwegian field study is presented with campfire data and management strategies to illustrate the integrative nature of common access and wilderness management principles for the managing of wildland recreation opportunities.     

Kin-related spatial structure in brown bears Ursus arctos

Kin-related social structure may influence reproductive success and survival and, hence, the dynamics of populations. It has been documented in many gregarious animal populations, but few solitary species. Using molecular methods and field data we tested: (1) whether kin-related spatial structure exists in the brown bear (Ursus arctos), which is a solitary carnivore, (2) whether home ranges of adult female kin overlap more than those of nonkin, and (3) whether multigenerational matrilinear assemblages, i.e., aggregated related females, are formed. Pairwise genetic relatedness between adult (5 years and older) female dyads declined significantly with geographic distance, whereas this was not the case for male–male dyads or opposite sex dyads. The amount of overlap of multiannual home ranges was positively associated with relatedness among adult females. This structure within matrilines is probably due to kin recognition. Plotting of multiannual home-range centers of adult females revealed formation of two types of matrilines, matrilinear assemblages exclusively using an area and dispersed matrilines spread over larger geographic areas. The variation in matrilinear structure might be due to differences in competitive abilities among females and habitat limitations. The influence of kin-related spatial structure on inclusive fitness needs to be clarified in solitary mammals.     

Comparative costs of promiscuity and monogramy: A test of reproductive effort theory

Summary Sharp-tailed sparrows Ammospiza caudacuta and seaside sparrows A. maritima co-occupy salt marshes in northeastern North America and are ecologically similar. Female caudacuta care for their young unaided, in comparison to martima's dual parental behavior. The annual reproductive effort of female caudacuta is higher than that of female maritima. Under reproductive effort theory, as both species' reproductive output is the same, female caudacuta should have a lower probability of survival than female maritima. However, the annual survival of both groups was the same. We believe that these results are possible only in highly productive habitats, where the relative cost differences of derived and ancestral mating systems may not be as great as in less productive environments. Lack of penalty in terms of lifetime fitness may have set the stage for the evolution of promiscuity in the sharp-tailed sparrow.In spite of their emancipation from parental duties, male caudacuta survive no better than females. We conclude that activities not directly related to care of young, such as patrolling large home ranges, may entail as much risk or energy expenditure as parental duties do.     

Using spatial patterns in illegal wildlife uses to reveal connections between subsistence hunting and trade

Although most often considered independently, subsistence hunting, domestic trade, and international trade as components of illegal wildlife use (IWU) may be spatially correlated. Understanding how and where subsistence and commercial uses may co‐occur has important implications for the design and implementation of effective conservation actions. We analyzed patterns in the joint geographical distribution of illegal commercial and subsistence use of multiple wildlife species in Venezuela and evaluated whether available data were sufficient to provide accurate estimates of the magnitude, scope, and detectability of IWU. We compiled records of illegal subsistence hunting and trade from several sources and fitted a random‐forest classification model to predict the spatial distribution of IWUs. From 1969 to 2014, 404 species and 8,340,921 specimens were involved in IWU, for a mean extraction rate of 185,354 individuals/year. Birds were the most speciose group involved (248 spp.), but reptiles had the highest extraction rates (126,414 individuals/year vs. 3,133 individuals/year for birds). Eighty‐eight percent of international trade records spatially overlapped with domestic trade, especially in the north and along the coast but also in western inland areas. The distribution of domestic trade was broadly distributed along roads, suggesting that domestic trade does not depend on large markets in cities. Seventeen percent of domestic trade records overlapped with subsistence hunting, but the spatial distribution of this overlap covered a much larger area than between commercial uses. Domestic trade seems to respond to demand from rural more than urban communities. Our approach will be useful for understanding how IWU works at national scales in other parts of the world.     

STORMFLOW SIMULATION USING A GEOGRAPHICAL INFORMATION SYSTEM WITH A DISTRIBUTED APPROACH1

ABSTRACT: With the increasing availability of digital and remotely sensed data such as land use, soil texture, and digital elevation models (DEMs), geographic information systems (GIS) have become an indispensable tool in preprocessing data sets for watershed hydrologic modeling and post processing simulation results. However, model inputs and outputs must be transferred between the model and the GIS. These transfers can be greatly simplified by incorporating the model itself into the GIS environment. To this end, a simple hydrologic model, which incorporates the curve number method of rainfall‐runoff partitioning, the ground‐water base‐flow routine, and the Muskingum flow routing procedure, was implemented on the GIS. The model interfaces directly with stream network, flow direction, and watershed boundary data generated using standard GIS terrain analysis tools; and while the model is running, various data layers may be viewed at each time step using the full display capabilities. The terrain analysis tools were first used to delineate the drainage basins and stream networks for the Susquehanna River. Then the model was used to simulate the hydrologic response of the Upper West Branch of the Susquehanna to two different storms. The simulated streamflow hydrographs compare well with the observed hydrographs at the basin outlet.