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Much research has focused on deforestation in the Amazon, particularly with proximity to roads and population centers as proximate causes. This research presents the analysis of rates and patterns of land cover change in Pando, northern Bolivia, an area with most of its tropical humid forest still intact. Using a decision tree classifier, five forest/non-forest (FNF) classifications were created for 1986, 1991, 1996, 2000, and 2005 from 40 Landsat images that were preprocessed and mosaicked. FNF trajectory images were created for each date pair to indicate areas of stable forest and non-forest, and areas and rates of de/reforestation. Mean patch size, perimeter-area ratio, fractal dimension, and aggregation index metrics were calculated for the FNF trajectory images based on increasing buffer distances from road and along the main access road. In 2005, forest covered 95% of the area in Pando. Large areas of aggregated deforestation occur nearest the department capital of Cobija, along the border with Brazil, and about 50 km west and east of Cobija along the principal access road. Deforestation becomes patchier with increased distance from the population center and laterally from the road. Multiple non-linear relationships exist between the fragmentation metrics and distance from road. The results have implications for understanding and managing the spatial contiguity of these forests, which provide valuable ecological services as well as the livelihood base for many inhabitants.

openAccessArticle: FalsePage Range: 67-67doi: 10.1016/j.ecocom.2012.03.002Harvest Date: 2016-01-12 15:11:21issueName:cover date: 2012-09-01pubType: Original Research Articl

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Droughts constitute natural hazards that affect water supply for ecosystems and human livelihoods. In 2013–2016, the Caribbean experienced the worst drought since the 1950s, and climate projections for the southern Caribbean predict less rainfall by the end of the 21st century. We assessed streamflow response to drought for a watershed in the Colombian Caribbean by analyzing the effects of drought length and land cover on streamflow recovery. We generated a calibrated SWAT model and created annual and monthly drought scenarios from rainfall records. We used our model to predict water yield for selected land covers (wet forest, shade coffee, shrub, and dry forest) under drought conditions. Annual scenarios resulted in water yield reductions of ~15 mm month−1 (wet forest, coffee, and shrub) and 5 mm month−1 (dry forest) for the first month after a two-year drought. Maximum water yield reductions for monthly scenarios occurred after a 10-month drought and were ~100 mm month−1 (wet forest, coffee, and shrub) and 20 mm month−1 (dry forest). Streamflow recovered within nine months (annual scenarios), and two to eight months (monthly scenarios) after drought termination. Drought response seems to be conditioned by climatic factors (rainfall seasonality and spatial variability) and catchment properties.

Forests in the United States are managed by multiple public and private entities making harmonization of available data and subsequent mapping of management challenging. We mapped four important types of forest management, production, ecological, passive, and preservation, at 250-meter spatial resolution in the Southeastern (SEUS) and Pacific Northwest (PNW) USA. Both ecologically and socio-economically dynamic regions, the SEUS and PNW forests represent, respectively, 22.0% and 10.4% of forests in the coterminous US. We built a random forest classifier using seasonal time-series analysis of 16 years of MODIS 16-day composite Enhanced Vegetation Index, and ancillary data containing forest ownership, roads, US Forest Service wilderness and forestry areas, proportion conifer and proportion riparian. The map accuracies for SEUS are 89% (10-fold cross-validation) and 67% (external validation) and PNW are 91% and 70% respectively with the same validation. The now publicly available forest management maps, probability surfaces for each management class and uncertainty layer for each region can be viewed and analysed in commercial and open-source GIS and remote sensing software.

While our sample did not demonstrate species differences in the degree of spatial autocorrelation of elastic moduli, there may be mechanical effects of heterogeneity (relative strength and rigidity) that do distinguish at the species or subfamilial level (i.e., colobines vs. cercopithecines). The potential connections of heterogeneity to diet and/or taxonomy remain to be discovered.