2,209 research outputs found

    Interpreting multiscale domains of tree cover disturbance patterns in North America

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    Spatial patterns at multiple observation scales provide a framework to improve understanding of pattern-related phenomena. However, the metrics that are most sensitive to local patterns are least likely to exhibit consistent scaling relations with increasing extent (observation scale). A conceptual framework based on multiscale domains (i.e., geographic locations exhibiting similar scaling relations) allows the use of sensitive pattern metrics, but more work is needed to understand the actual patterns represented by multiscale domains. The objective of this study was to improve the interpretation of scale-dependent patterns represented by multiscale domains. Using maps of tree cover disturbance covering North American forest biomes from 2000 to 2012, each 0.09-ha location was described by the proportion and contagion of disturbance in its neighborhood, for 10 neighborhood extents from 0.81 ha to 180 km2. A k-means analysis identified 13 disturbance profiles based on the similarity of disturbance proportion and contagion across neighborhood extent. A wall to wall map of multiscale domains was produced by assigning each location (disturbed and undisturbed) to its nearest disturbance profile in multiscale pattern space. The multiscale domains were interpreted as representing two aspects of local patterns – the proximity of a location to disturbance, and the interior-exterior relationship of a location relative to nearby disturbed areas.Ye

    Conservation of the Longleaf Pine Ecosystem: Ecology and Social Context

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    Worldwide, ecosystems are increasingly influenced by human actions and land use. As a result, landscapes include a mosaic of human land uses along with fragments of relatively natural habitat. Effective conservation requires a consideration of both local sites and the broader social and ecological landscape in which they occur. Partnerships among multiple landowners have become a popular way to implement conservation across broad extents because they can be effective at integrating ecological goals with their social context. My research examines how collaborative partnerships conduct conservation in the longleaf pine ecosystem of the US southeast. Longleaf pine communities provide important habitat for many plants and animals, and when frequently burned, can have among the highest levels of plant diversity of any ecosystem in the world. However, the ecosystem has become severely degraded, and several collaborative partnerships have been established with the goal of restoring the ecosystem. My research investigates the relationship between local sites and their ecological and social contexts, and the collaborative partnerships that implement longleaf pine ecosystem conservation. First, I examine the relationship between metrics of landscape heterogeneity and local plant species diversity. I then synthesize the strategies used by three collaborative partnerships in the conservation of longleaf pine ecosystems. Finally, I investigate how decisions are made about prescribed burning, a major management tool for restoring the longleaf pine ecosystem. My results illustrate that heterogeneity in environmental variables measured across a range of scales is related to local plant diversity, suggesting that incorporating broad-scale context into conservation efforts in the longleaf pine ecosystem is important. In addition, a focus on long-term ecosystem sustainability drives the strategies used by successful collaborative partnerships in the longleaf pine ecosystem. However, decisions made by prescribed burn practitioners are risk-averse, and tend to burn sites in good condition, located away from developed areas. Thus, prescribed burning is less likely to accomplish restoration of degraded sites. Finding ways to alleviate the risks associated with burning degraded sites will be crucial for ecosystem restoration. Taken together, my results provide guidelines that will be useful for informing collaborative partnerships and restoring the critically endangered longleaf pine ecosystem

    A global evaluation of forest interior area dynamics using tree cover data from 2000 to 2012

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    Context Published maps of global tree cover derived from Landsat data have indicated substantial changes in forest area from 2000 to 2012. The changes can be arranged in different patterns, with different conse- quences for forest fragmentation. Thus, the changes in forest area do not necessarily equate to changes in forest sustainability. Objective The objective is to assess global and regional changes in forest fragmentation in relation to the change of forest area from 2000 to 2012. Methods Using published global tree cover data, forest and forest interior areas were mapped in 2000 and 2012. The locations of forest interior change were compared to the locations of overall forest change to identify the direct (pixel level) and indirect (landscape level) components of forest interior change. The changes of forest interior area were compared to the changes of total forest area in each of 768 ecological regions. Results A 1.71 million km2 (3.2 %) net loss of global forest area translated to a net loss of 3.76 million km2 (9.9 %) of forest interior area. The difference in loss rates was consistent in most of the 768 ecological regions. The indirect component accounted for 2.44 million km2 of the net forest interior change, com- pared to 1.32 million km2 that was attributable to the direct component. Conclusion Forest area loss alone from 2000 to 2012 underestimates ecological risks from forest fragmen- tation. In addition to the direct loss of forest, there was a widespread shift of the remaining global forest to a more fragmented condition.JRC.H.3-Forest Resources and Climat

    The National Singing Programme for primary schools in England: an initial baseline study

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    The ‘Sing Up’ National Singing Programme for Primary schools in England was launched in November 2007 under the UK Government’s ‘Music Manifesto’. ‘Sing Up’ is a four-year programme whose overall aim is to raise the status of singing and increase opportunities for children throughout the country to enjoy singing as part of their everyday lives, in and out of school. As part of the Programme’s research evaluation, a key focus has been to build an initial picture of singing in Primary schools across England. This information could then be used as a ‘baseline’ by which the programme’s subsequent impact could be judged, including ‘before’ and ‘after’ measures of schools that receive particular ‘Sing Up’ input. This paper reports an overview of key outcomes of first five months of baseline profiling (October, 2007 to February 2008), embracing analyses of the singing behaviours of 3,472 children in 76 Primary schools. These findings are complimented by additional analyses of children’s views on singing in and out of school; and the self-efficacy of their class teachers’ (n=90), both as singers and as teachers of singing

    Education and training in I-O Psychology: Leaving the Psychology tower: Nontraditional programs in I/O Psychology

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    The need for programs that accommodate diverse types of students and adopt an interdisciplinary approach to the study of organizations has led universities with traditional I-O programs to also offer nontraditional programs. Nontraditional programs tend to attract highly heterogeneous sets of students in terms of age and academic and professional backgrounds or may be tailored for special types of students. Due to the mixed student population and high percentage of working adults, nontraditional programs tend to be more application and applied-research oriented than their traditional program counterparts. Faculty, students, and administrators of nontraditional programs face a variety of challenges. In this column, we explore and address these challenges based on our experiences in running and teaching in such programs. We hope this column will provide the impetus for open dialogue among I-O psychologist educators regarding how to diversify educational opportunities in I-O psychology

    fMRI of Monkey Visual Cortex

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    While functional magnetic resonance imaging (fMRI) is now used widely for demonstrating neural activity-related signals associated with perceptual, motor, and cognitive processes in humans, to date this technique has not been developed for use with nonhuman primates. fMRI in monkeys offers a potentially valuable experimental approach for investigating brain function, which will complement and aid existing techniques such as electrophysiology and the behavioral analysis of the effects of brain lesions. There are, however, a number of significant technical challenges involved in using fMRI with monkeys. Here, we describe the procedures by which we have overcome these challenges to carry out successful fMRI experiments in an alert monkey, and we present the first evidence of activity-related fMRI signals from monkey cerebral cortex

    Modeling the impacts of hot drought on forests in Texas

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    IntroductionUnder climate change, drought is increasingly affecting forest ecosystems, with subsequent consequences for ecosystem services. An historically exceptional drought in Texas during 2011 caused substantial tree mortality. We used 2004–2019 Forest Inventory and Analysis (FIA) data and state-wide weather data to examine the climatic conditions associated with this elevated tree mortality.MethodsWe measured moisture extremes (wet to dry) using the Standardized Precipitation Evapotranspiration Index (SPEI) at two timescales (12- and 36-month). We quantified heat wave severity using the Heat Wave Magnitude Index daily (HWMId) over the same period. We performed statistical modeling of the relationship between tree mortality and these indices across four Texas regions (Southeast, Northeast, North Central, and South) and for prominent tree genera (Pinus, Juniperus, Quercus, Liquidambar, Prosopis, and Ulmus) as well as selected species: Quercus stellata, Q. virginiana, and Q. nigra.ResultsThe highest tree mortality was observed between 2011 and 2013. We found similarity in the trends of the 12- and 36-month SPEI, both of which exhibited more extreme negative intensities (i.e., drought) in 2011 than other years. Likewise, we found that the extreme heat experienced in 2011 was much greater than what was experienced in other years. The heat waves and drought were more intense in East (i.e., Southeast and Northeast) Texas than Central (i.e., North Central and South) Texas. In gradient boosted regression models, the 36-month SPEI had a stronger empirical relationship with tree mortality than the 12-month SPEI in all regions except South Texas, where HWMId had more influence than SPEI at either timescale. The correlations between moisture extremes, extreme heat, and tree mortality were high; typically, mortality peaked after periods of extreme moisture deficit rather than surplus, suggesting that the mortality was associated with hot drought conditions. The effects of extreme heat outweighed those of SPEI for all tree genera except oaks (Quercus). This was also true for oak species other than water oak (Q. nigra). In generalized additive models, the median trend showed tree mortality of Prosopis was higher during conditions of moderate drought (SPEI36 ∼ –1) or worse, but for Pinus and Quercus, mortality started to become apparent under mild drought conditions (SPEI36 ∼ –0.5). The impacts of extreme heat on the mortality of Juniperus occurred when heat wave magnitude reached the ultra extreme category (HWMId > 80) but occurred at lower magnitude for Liquidambar.DiscussionIn summary, we identified risks to Texas forest ecosystems from exposure to climate extremes. Similar exposure can be expected to occur more frequently under a changing climate

    How global biodiversity hotspots may go unrecognized: Lessons from the North American Coastal Plain

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    © 2014 John Wiley & Sons Ltd. Biodiversity hotspots are conservation priorities. We identify the North American Coastal Plain (NACP) as a global hotspot based on the classic definition, a region with \u3e 1500 endemic plant species and \u3e 70% habitat loss. This region has been bypassed in prior designations due to misconceptions and myths about its ecology and history. These fallacies include: (1) young age of the NACP, climatic instability over time and submergence during high sea-level stands; (2) climatic and environmental homogeneity; (3) closed forest as the climax vegetation; and (4) fire regimes that are mostly anthropogenic. We show that the NACP is older and more climatically stable than usually assumed, spatially heterogeneous and extremely rich in species and endemics for its range of latitude, especially within pine savannas and other mostly herbaceous and fire-dependent communities. We suspect systematic biases and misconceptions, in addition to missing information, obscure the existence of similarly biologically significant regions world-wide. Potential solutions to this problem include (1) increased field biological surveys and taxonomic determinations, especially within grassy biomes and regions with low soil fertility, which tend to have much overlooked biodiversity; (2) more research on the climatic refugium role of hotspots, given that regions of high endemism often coincide with regions with low velocity of climate change; (3) in low-lying coastal regions, consideration of the heterogeneity in land area generated by historically fluctuating sea levels, which likely enhanced opportunities for evolution of endemic species; and (4) immediate actions to establish new protected areas and implement science-based management to restore evolutionary environmental conditions in newly recognized hotspots
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