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Land Cover Analysis for Urban Foresters and Municipal Planners: Examples from Iowa

Journal Articles & Books
Dezembro, 2012

Contemporary land-use change and impacts on natural systems are of concern throughout the Cornbelt region, where agricultural activities have extensively altered the landscape. Land-use changes driven by urbanization throughout this region could have a disproportionate impact on remaining natural areas, particularly forests. We used readily available data sets and software to assess land cover change for four municipalities in Iowa and to examine the usefulness of this approach for urban foresters and planners interested in understanding/predicting impacts of land cover change.

Comparing the relative contributions of biotic and abiotic factors as mediators of species’ distributions

Journal Articles & Books
Dezembro, 2013

Models to predict species’ ranges have chiefly been limited to abiotic variables. However, the full ecological niche depends on a myriad of factors, both biotic and abiotic, that often correspond to completely different data types. We applied a methodology based on data mining techniques to construct ecological niche models composed of biotic as well as abiotic variables using three quite different sets of variables: climatic layers, maps of land cover and point collections of Mexican mammals.

web-based planning support tool for sediment management in a meso-scale river basin in Western Central Brazil

Journal Articles & Books
Dezembro, 2013

In scope of an IWRM concept for the Federal District, Western Central Brazil we developed a planning support tool, which enables non-experts to test the effects of land-use and land-cover change (LULCC) on landscape processes and landscape functions (LPF) related to sediment generation and retention. For this purpose we developed the web-based tool Letsmap do Brasil. The tool has two principal layers. The upper layer contains information on land use and its effect on LPF, i.e. sediment retention, runoff control, nitrogen loss control and agronomic value.

Assessment of nitrogen and phosphorus loads and causal factors from different land use and soil types in the Three Gorges Reservoir Area

Journal Articles & Books
Dezembro, 2013
China

It is important to identify nitrogen (N) and phosphorus (P) from non-point sources (NPS) to protect watershed water quality. However, few studies have been conducted in a large basin to determine the sources and causal factors of N and P from multiple land use and soil types. In this study, the Soil and Water Assessment Tool (SWAT) was applied in support of the Small-scale Watershed Extended Method (SWEM) in the Three Gorges Reservoir Region (TGRR), China. The first-order error analysis (FOEA) was used to identify the key sub-processes that affected the occurrence of NPS pollution.

Managing carbon in a multiple use world: The implications of land-use decision context for carbon management

Journal Articles & Books
Dezembro, 2013

Human land use contributes significantly to the growth of greenhouse gases in the atmosphere. Changes in land management practices have been proposed as a critical and cost-effective mechanism for reducing greenhouse gas emissions and promoting the storage of additional carbon in vegetation and soils. However many discussions of the potential for land use to mitigate climate change only take into account biophysical factors such as vegetation and land cover and neglect how the agency of land owners themselves affects whether additional carbon storage can be achieved.

Landscape factors influencing lake phosphorus concentrations across Minnesota

Journal Articles & Books
Dezembro, 2013

Total phosphorus (TP) concentrations are known to be a significant factor influencing fish populations in Minnesota lakes. Consequently, a primary focus of the Minnesota Department of Natural Resources to address fish habitat in lakes across the state has been to determine relationships between TP concentrations and watershed conditions in Minnesota lakes. Because phosphorus concentrations in Minnesota lakes vary widely corresponding to differences in geomorphology, nutrient criteria were established by the Minnesota Pollution Control Agency for specific ecoregions.

Mapping syndromes of land change in Spain with remote sensing time series, demographic and climatic data

Journal Articles & Books
Dezembro, 2013
Espanha

The country of Spain is representative of land change processes in Mediterranean member states of the European Union (EU). These land change processes are often triggered by European, national and sub-national policies and include widespread land abandonment and urbanisation trends, as well as an increase in land use intensities accompanied by strong exploitation of water resources. The Mediterranean is part of the dryland ecoregion, which is particularly vulnerable to ecosystem degradation.

Sample-based estimation of “contagion metric” using line intersect sampling method (LIS)

Journal Articles & Books
Dezembro, 2015
Suécia

Quantification of landscape pattern is of primary interest in landscape ecological studies. For quantification purposes, a large number of landscape metrics have been developed, with definitions based on measurable patch attributes. Calculation of these metrics is commonly conducted on wall-to-wall maps, whereas a new interest is to use sample data. It is argued that a sample survey takes less time and results are more reliable. The overall objective in this paper was to present the potential of the line interest sampling method for estimating a special contagion metric.

Case Study in Large-scale Wetland Restoration at Seney National Wildlife Refuge, Upper Michigan, U.S.A

Journal Articles & Books
Dezembro, 2013

A large wetland drainage project was initiated in 1912 near the town of Seney, Michigan, U.S.A. This project included the construction of a series of ditches through a large peatland to drain the land for agricultural use. The largest of these ditches was the 35 km long Walsh Ditch. Much of the drained wetland affected by the Walsh Ditch is now managed by the U.S. Fish and Wildlife Service as part of Seney National Wildlife Refuge.

Persistence and habitat associations of Purple Martin roosts quantified via weather surveillance radar

Journal Articles & Books
Dezembro, 2016
América do Norte

CONTEXT: Weather surveillance radars (WSR) have been used to locate roost sites used by Purple Martins (Progne subis) for decades. Improvements in radar data processing and accessibility now make it possible to monitor roosts over a broad spatial scale. OBJECTIVES: We sought to locate all of the Purple Martin roosts in North America and to use the data to evaluate (1) the land cover types associated with roosts (2) relationships among roost persistence, land cover type, and regional population trends.

Importance of Agricultural Landscapes as Key Nesting Habitats for the American Black Duck in Maritime Canada

Journal Articles & Books
Dezembro, 2012

Given historical patterns of decline, the American Black Duck (Anas rubripes) has long been a species of concern. To support the identification of core Maritime habitat, the distribution of breeding ducks was mapped at the landscape scale through the combination of GIS-based land cover information and five years of intensive aerial surveys (2006–2010). A predictive, mixed effects model was used to generate the maps, based on the weighted average of coefficients for the top 95% of all-possible models (as measured by AIC weights).