Treesearch

Fire scars are initiated by cambial necrosis caused by localized lethal heating of the tree stem. Scars develop as part of the linked survival processes of compartmentalization and wound closure. The position of scars within dated tree ring series is the basis for dendrochronological reconstruction of fire history. Macroanatomical features were described for western larch (Larix occidentalis Nutt.), ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson), and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) injured by fire in 2003 and harvested in 2011 at the Lolo National...

The conservation value of residential landscapes is becoming increasingly apparent in our urbanizing world. The ecological characteristics of residential areas are largely determined by the decisions of many individual "managers." In these complex socio-ecological systems, it is important to understand the factors that motivate human decision-making. Our first objective was to quantify wildlife resources and management activities in residential landscapes and compare vegetation in front and back yards. Our second objective was to test three hypotheses linked with variation in yards:...

Streams and their accompanying riparian environments are intrinsic components of terrestrial carbon cycling. However, they have been understudied in terms of the magnitude of their storage components and the role of disturbance in determining carbon storage capacity. This study presents partial carbon budgets for stream-riparian corridors along six study reaches in mountain headwater streams of southeast Wyoming to evaluate the impact of tie-driving, a historic disturbance legacy, on contemporary carbon storage. Detailed measurements of biomass were collected for in-stream components of...

Rivers are dynamic components of the terrestrial carbon cycle and provide important functions in ecosystem processes. Although rivers act as conveyers of carbon to the oceans, rivers also retain carbon within riparian ecosystems along floodplains, with potential for long-term (> 102 years) storage. Research in ecosystem processing emphasizes the importance of organic carbon (OC) in river systems, and estimates of OC fluxes in terrestrial freshwater systems indicate that a significant portion of terrestrial carbon is stored within river networks. Studies have examined soil OC on floodplains,...

Increasing costs of wildfire management have highlighted the need to better understand suppression expenditures and potential tradeoffs of land management activities that may affect fire risks. Spatially and temporally descriptive data is used to develop a model of wildfire suppression expenditures, providing new insights into the role of spatial and temporal heterogeneity in determining expenditures. Incorporating heterogeneity improves model fit and predictive ability over a model with data based on the point and time of fire ignition. The model is potentially useful for providing...

Current projections of future climate change foretell potentially transformative ecological changes that threaten communities globally. Using two case studies from the United States Intermountain West, this article highlights the ways in which a better articulation between theory and methods in research design can generate proactive applied tools that enable locally grounded dialogue about the future, including key vulnerabilities and potential adaptive pathways. Moreover, anthropological knowledge and methods, we find, are well-suited to the complexities and uncertainties that surround...

Machine learning approaches such as random forest have increased for the spatial modeling and mapping of continuous variables. Random forest is a non-parametric ensemble approach, and unlike traditional regression approaches there is no direct quantification of prediction error. Understanding prediction uncertainty is important when using model-based continuous maps as inputs to other modeling applications such as fire modeling. Here we use a Monte Carlo approach to quantify prediction uncertainty for random forest regression models. We test the approach by simulating maps of dependent and...

Forests are a crucial element not only of landscapes but also of human living conditions. Covering nearly a third of the earth's land surtace, they stabilize surface soil, prevent erosion and play an essential role in water resource management at the watershed and local levels. They regulate climate and improve air quality. At the same time they are an important resource for the regional economy (wood production, recreation and tourism) and are an important cultural and social heritage of the local and regional human activities. They provide habitats for a multitude of animal and plant...

Characterizing forest soil properties with high variability is challenging, sometimes requiring large numbers of soil samples. Soil bulk density is a standard variable needed along with element concentrations to calculate nutrient pools. This study aimed to determine the optimal sample size, the number of observation (n), for predicting the soil bulk density with a precision of ±10% at a 95% confidence level among different soil types. We determined soil bulk density samples at three depths at 186 points distributed over three different 1-ha forest sites. We calculated n needed for...

Future forests are being shaped by changing climate and disturbances. Climate change is causing large-scale forest declines globally, in addition to distributional shifts of many tree species. Because environmental cues dictate insect seasonality and population success, climate change is also influencing tree-killing bark beetles. The mountain pine beetle, Dendroctonus ponderosae, is a major disturbance in Pinus forests of the western US. Using a mechanistic, phenology-based demographic model driven by downscaled daily temperature data, we describe recent and future spatial and temporal...