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Abstract: Wildfires play a formative role in the processes that have created the ecosystems of the Southern Rockies Ecoregion (SRE). The extent of wildfires is influenced mainly by precipitation and temperature, which control biomass growth and fuel moisture. Forecasts of climate change in the SRE show an increase in temperatures, bringing warmer springs with earlier runoff and longer fire seasons. Increasing wildfire extent and intensity would affect human safety, livelihoods, and landscapes. Our summary of historical wildfire records from the national forests of the SRE from 1930 to 2006 revealed an order of magnitude increase in the annual number of fires recorded over the full time period and in the number of large fires since 1970. We developed a model of percent burned area in the SRE for the period 1970–2006 using temperature and precipitation variables (R 2 =0.51, p =1.7E-05). We applied this model to predict percent burned area using data from two downscaled global circulation models (GCMs), for the Intergovernmental Panel on Climate Change Special Report Emissions Scenarios A2 (projects high increases in temperature) and B1 (projects lower temperature increases), for the time period 2010–2070. The results showed increasing trends in median burned areas for all scenarios and GCM combinations with higher increases for the B1 scenario. The results suggest that precipitation increases could at least partially compensate for the effect of temperature increases on burned area but the strength of this ameliorating effect of precipitation will remain uncertain until the GCMs are further developed. [Copyright &y& Elsevier]

Abstract: In Rondônia State, Brazil, settlement processes have cleared 68,000km2 of tropical forests since the 1970s. The intensity of deforestation has differed by region depending on driving factors like roads and economic activities. Different histories of land-use activities and rates of change have resulted in mosaics of forest patches embedded in an agricultural matrix. Yet, most assessments of deforestation and its effects on vegetation, soil and water typically focus on landscape patterns of current conditions, yet historical deforestation dynamics can influence current conditions strongly. Here, we develop and describe the use of four land-use dynamic indicators to capture historical land-use changes of catchments and to measure the rate of deforestation (annual deforestation rate), forest regeneration level (secondary forest mean proportion), time since disturbance (mean time since deforestation) and deforestation profile (deforestation profile curvature). We used the proposed indices to analyze a watershed located in central Rondônia. Landsat TM and ETM+ images were used to produce historical land-use maps of the last 18 years, each even year from 1984 to 2002 for 20 catchments. We found that the land-use dynamics indicators are able to distinguish catchments with different land-use change profiles. Four categories of historical land-use were identified: old and dominant pasture cover on small properties, recent deforestation and dominance of secondary growth, old extensive pastures and large forest remnants and, recent deforestation, pasture and large forest remnants. Knowing historical deforestation processes is important to develop appropriate conservation strategies and define priorities and actions for conserving forests currently under deforestation. [Copyright &y& Elsevier]

Abstract: Central Rondônia is one of the most deforested regions in the Brazilian Amazon and contains areas at different stages of degradation forming a gradient from mature forest to highly urbanized and built-up areas. Regional data from satellite imagery are available from the 1980s, but apart from studies that quantify deforestation, the broad-scale landscape dynamics of Rondônia have not been examined well. This paper assesses the landscape changes between 1984 and 2002 in a watershed located in the central region of the state of Rondônia, Brazil, which has undergone systematic and rapid deforestation due to introduction of pasture that began in the 1970s. Bi-annual Landsat TM/ETM+ images from 1984 to 2002 were classified into three broad land cover types: mature forest, secondary forest, and pasture, resulting in a time series of land-use/land-cover maps. Landscape changes were evaluated by computing a cross tabulation between years, transition rates, and landscape metrics related to size, density, connectivity, configuration, and deforested patches distribution related to patch size and spatial proximity to roads and old pastures. Transition probability functions were fitted to the temporal series to predict land-use changes for the next 10 years, for three different scenarios: (1) continued land-use change; (2) eliminating clear-cutting and selective logging; and (3) eliminating clear-cutting, selective logging, and secondary vegetation clearing. Current land-use transitions cannot be sustained beyond the next 10–15 years. A more sustainable scenario for the region requires a major reduction of deforestation activities, implementing the “permanent preservation area” policy along riversides, and controlling land-use transitions at balanced levels. We recommend that forest managers in regions facing similar deforestation pressures should strive to maintain at least 35% mature or primary forest, because landscape fragmentation proceeds rapidly below this critical threshold. [Copyright &y& Elsevier]

Discusses a general approach to estimate the cumulative effects of land use change on wildlife habitat using Summit County, Colorado, as a case study. Effects of development on wildlife and wildlife habitat; Development density and pattern; Density-disturbance functional relationship; Fragmentation of habitat caused by development.

A variety of land-use and land-cover (LULC) models operating at scales from local to global have been developed in recent years, including a number of models that provide spatially explicit, multi-class LULC projections for the conterminous United States. This diversity of modeling approaches raises the question: how consistent are their projections of future land use? We compared projections from six LULC modeling applications for the United States and assessed quantitative, spatial, and conceptual inconsistencies. Each set of projections provided multiple scenarios covering a period from roughly 2000 to 2050. Given the unique spatial, thematic, and temporal characteristics of each set of projections, individual projections were aggregated to a common set of basic, generalized LULC classes (i.e., cropland, pasture, forest, range, and urban) and summarized at the county level across the conterminous United States. We found very little agreement in projected future LULC trends and patterns among the different models. Variability among scenarios for a given model was generally lower than variability among different models, in terms of both trends in the amounts of basic LULC classes and their projected spatial patterns. Even when different models assessed the same purported scenario, model projections varied substantially. Projections of agricultural trends were often far above the maximum historical amounts, raising concerns about the realism of the projections. Comparisons among models were hindered by major discrepancies in categorical definitions, and suggest a need for standardization of historical LULC data sources. To capture a broader range of uncertainties, ensemble modeling approaches are also recommended. However, the vast inconsistencies among LULC models raise questions about the theoretical and conceptual underpinnings of current modeling approaches. Given the substantial effects that land-use change can have on ecological and societal processes, there is a need for improvement in LULC theory and modeling capabilities to improve acceptance and use of regional- to national-scale LULC projections for the United States and elsewhere. [ABSTRACT FROM AUTHOR]

Highlights: [•] We model human housing density projections through the year 2050. [•] We predict changes in bird distribution models resulting from future development. [•] The overall occupancy of each species decreased by as much as 38% in the year 2050. [•] Ninety-seven percent of towns experienced some decline in species occupancy. [•] Spatial planning evaluates trade-offs between development and species viability. [Copyright &y& Elsevier]