tailieunhanh - báo cáo hóa học:" Refining spatial neighbourhoods to capture terrain effects"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Refining spatial neighbourhoods to capture terrain effects | Nelson and Robertson Ecological Processes 2012 1 1 http content 1 1 3 D Ecological Processes a SpringerOpen Journal RESEARCH Open Access Refining spatial neighbourhoods to capture terrain effects Trisalyn A Nelson1 and Colin Robertson2 Abstract Introduction Spatially explicit ecological research has increased substantially in the past 20 years. Most spatial approaches require the definition of a spatial neighbourhood or the region over which spatial relationships are modelled or assessed. Spatial neighbourhood definitions impact analysis results and there are benefits in considering neighbourhood definitions that better capture ecological processes. The goal of this research is to present a simple and flexible approach in constraining ecological spatial neighbourhoods using terrain data. Methods Using watershed boundaries we can restrict spatial neighbourhoods from combining populations or processes that should be separated by terrain effects. We demonstrate the need for ecological constraints by way of a simulation study and highlight our approach with a case study examining mountain pine beetle Dendroctonus ponderosae Coleoptera Hopkins infestation hot spots. Results Our results demonstrate how failure to constrain neighbourhoods can lead to errors when the spatial signals from unrelated populations are mixed. Also unconstrained spatial neighbourhoods can unintentionally detect spatial relationships across many scales. Conclusions There will be benefits to studies that develop new ecology-based approaches in defining spatial neighbourhoods that better illuminate ecological function of phenomena under study. Keywords spatial weights spatial analysis spatial ecology hot spots topography Introduction Spatial ecology has developed over the past two decades as spatial research questions have intersected with advancing geographically explicit technology such as global positioning systems GPS geographic information systems GIS and remote .