Filters: partyWithName: Phillip J van Mantgem (X)
21 results (27ms)|
Filters
Date Range
Extensions Types Contacts
Categories Tag Types
|
This dataset records mortality-- including involvement of bark beetles-- and burn severity information for trees in long term forest dynamics plots in Sequoia National Park and Yosemite National Park that experienced fire. These data support the following publication: Furniss, T.J., Das, A.J., van Mantgem, P.J., Stephenson, N.L. and Lutz, J.A., 2021. Crowding, climate, and the case for social distancing among trees. Ecological Applications, p.e2507, https://doi.org/10.1002/eap.2507
Categories: Data;
Tags: California,
Forestry,
Sequoia National Park,
Sierra Nevada,
USGS Science Data Catalog (SDC),
Over the past four decades, annual area burned has increased significantly in California and across the western USA. This trend reflects a confluence of intersecting factors that affect wildfire regimes. It is correlated with increasing temperatures and atmospheric vapour pressure deficit. Anthropogenic climate change is the driver behind much of this change, in addition to influencing other climate-related factors, such as compression of the winter wet season. These climatic trends and associated increases in fire activity are projected to continue into the future. Additionally, factors related to the suppression of the Indigenous use of fire, aggressive fire suppression and, in some cases, changes in logging practices...
Categories: Publication;
Types: Citation
Abstract (from Ecological Society of America): Large, severe fires are becoming more frequent in many forest types across the western United States and have resulted in tree mortality across tens of thousands of hectares. Conifer regeneration in these areas is limited because seeds must travel long distances to reach the interior of large burned patches and establishment is jeopardized by increasingly hot and dry conditions. To better inform postfire management in low elevation forests of California, USA, we collected 5‐year postfire recovery data from 1,234 study plots in 19 wildfires that burned from 2004–2012 and 18 years of seed production data from 216 seed fall traps (1999–2017). We used this data in conjunction...
Categories: Publication;
Types: Citation
This release consists of data collected from 26 plots in two national parks over a 19-year period. The data consists of plot-level seed counts for three genera, number of seed traps, live tree basal area, plot area, and climate metrics from the gridmet gridded data set, the daymet gridded data set, the PRISM gridded data set, and two nearby COOP stations.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: California,
Holocene,
Sequoia-Kings National Park,
Terrestrial surface,
USGS Science Data Catalog (SDC),
Ecosystems are dynamic systems with complex responses to environmental variation. In response to pervasive stressors of changing climate and disturbance regimes, many ecosystems are realigning rapidly across spatial scales, in many cases moving outside of their observed historical range of variation into alternative ecological states. In some cases, these new states are transitory and represent successional stages that may ultimately revert to the pre-disturbance condition; in other cases, alternative states are persistent and potentially self-reinforcing, especially under conditions of altered climate, disturbance regimes, and influences of non-native species. These reorganized states may appear novel, but reorganization...
Categories: Publication;
Types: Citation
These data represent stem growth from whitebark pine at 27 sites in the Sierra Nevada of California. Values for stem growth were derived from increment cores, processed following standard methods. Samples were also compared against a genomic data collected at the same trees. These data support the following publication: van Mantgem, P.J., Milano, E.R., Dudney, J., Nesmith, J.C.B, Vandergast, A.G., and Zald, H.S.J., 2023. Growth, drought response, and climate-associated genomic structure in whitebark pine in the Sierra Nevada of California. Ecology and Evolution. https://doi.org/10.1002/ece3.10072.
Categories: Data;
Tags: California,
Sierra Nevada,
USGS Science Data Catalog (SDC),
biota,
carbon isotope analysis,
This dataset provides seedling density and site characteristics for 131 plots in Whiskeytown National Recreation Area in California, USA. Site characteristics include modeled seed availability and terrain indices calculated using a 1 meter resolution digital elevation model (DEM).
Categories: Data;
Tags: California,
Ecology,
Forestry,
Remote Sensing,
USGS Science Data Catalog (SDC),
Categories: Publication;
Types: Citation
Categories: Publication;
Types: Citation
This table provides, for each of the 403 species used in our analysis, various documentary information as well as the fitted parameters for the relationship between mass growth rate and the natural log of tree size. The independent variable ln(mass) was divided into bins and a separate line segment was fitted to mass growth rate versus ln(mass) in each bin so that the line segments met at the bin divisions. Mass and growth rate were in megagrams (Mg) and Mg yr-1 respectively. Bin divisions were not assigned a priori but were fitted by the model separately for each species. We fitted models with 1, 2, 3, and 4 bins, and selected the model receiving the most support by Akaike’s Information Criterion for each species....
Postfire Spatial Conifer Restoration Planning Tool (POSCRPT) R package (and web version) predicts the probability of post-fire conifer regeneration for fire data supplied by the user. The predictive model was fit using presence/absence data collected five years after wildfire, from 1,234 4.4m radius plots (60m2), spanning 19 wildfires in California. Please refer to Stewart et al. (2020) for more details. The poscrptR tool is designed to simplify the process of predicting post-fire conifer regeneration under different precipitation and seed production scenarios. The app was designed to use Rapid Assessment of Vegetative Condition (RAVG) data inputs. The RAVG website has both RdNBR and fire perimeter data sets...
This data consists of observations of individual trees that were subjected to prescribed fire in western US national parks. Information on individual trees include measurements of tree live/dead status, growth, size, competition, and fire-caused damage. The data also includes estimates of plot-level vapor pressure deficit anomaly before fire. These data support the following publication: van Mantgem, P.J., Falk, D.A., Williams, E.C., Das, A.J., and Stephenson, N.L., 2020, The influence of pre-fire growth on post-fire tree mortality for common conifers in western US parks. International Journal of Wildland Fire. First posted - August 28, 2018 (available from author) Revised - Febuary 10, 2020
Large, severe fires are becoming more frequent in many forest types across the western United States and have resulted in tree mortality across tens of thousands of hectares. Conifer regeneration in these areas is limited because seeds must travel long distances to reach the interior of large burned patches and establishment is jeopardized by increasingly hot and dry conditions. To better inform postfire management in low elevation forests of California, USA, we collected 5‐yr postfire recovery data from 1,234 study plots in 19 wildfires that burned from 2004–2012 and 18 yrs of seed production data from 216 seed fall traps (1999–2017). We used these data in conjunction with spatially extensive climate, topography,...
Categories: Publication;
Types: Citation
Abstract Background Forest and nonforest ecosystems of the western United States are experiencing major transformations in response to land-use change, climate warming, and their interactive effects with wildland fire. Some ecosystems are transitioning to persistent alternative types, hereafter called “vegetation type conversion” (VTC). VTC is one of the most pressing management issues in the southwestern US, yet current strategies to intervene and address change often use trial-and-error approaches devised after the fact. To better understand how to manage VTC, we gathered managers, scientists, and practitioners from across the southwestern US to collect their experiences with VTC challenges, management responses,...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service
Forests sequester the majority of the terrestrial biosphere’s carbon and are key components of the global carbon cycle, potentially contributing substantial feedbacks to ongoing climatic changes. It is therefore remarkable that no consensus yet exists about the fundamental nature of tree mass growth (and thus carbon sequestration rate). Specifically, does tree mass growth rate increase, decrease, or stay the same with increasing tree size? The answer could have profound implications for our ability to forecast the role of forests in the global carbon cycle and to devise appropriate adaptation and mitigation strategies for forests in the face of rapid climatic changes. We will conduct the first global-scale characterization...
These data support poscrptR (Wright et al. 2021). poscrptR is a shiny app that predicts the probability of post-fire conifer regeneration for fire data supplied by the user. The predictive model was fit using presence/absence data collected in 4.4m radius plots (60 square meters). Please refer to Stewart et al. (2020) for more details concerning field data collection, the model fitting process, and limitations. Learn more about shiny apps at https://shiny.rstudio.com. The app is designed to simplify the process of predicting post-fire conifer regeneration under different precipitation and seed production scenarios. The app requires the user to upload two input data sets: 1. a raster of Relativized differenced Normalized...
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Botany,
California,
Forestry,
Oregon,
USGS Science Data Catalog (SDC),
These data represent stem growth, needle length growth, and carbon stable isotope ratios from whitebark pine at 27 sites in the Sierra Nevada of California. Values for stem growth were derived from increment cores, processed following standard methods. Needle characteristics were captured for individual trees across all years needles were present on the internodes. Needle length was measured in the lab for three healthy needles per tree and initiation year. For stable carbon isotopes, samples were pulverized in the lab and then were sent to the Analytical Laboratory at the University of California, Davis (UC Davis) for weighing and encapsulation. Carbon and nitrogen isotopic values were estimated by the Stable Isotope...
Categories: Data;
Tags: California,
Forestry,
Sierra Nevada,
USGS Science Data Catalog (SDC),
biota,
Prescribed fire reduces fire hazards by removing dead and live fuels (small trees and shrubs). Reductions in forest density following prescribed fire treatments (often in concert with mechanical treatments) may also lessen competition so that residual trees might be more likely to survive when confronted with additional stressors, such as drought. The current evidence for these effects is mixed and additional study is needed. Previous work found increased tree survivorship in low elevation forests with a recent history of fire during the early years of an intense drought (2012 to 2014) in national parks in the southern Sierra Nevada. We extend these observations through additional years of intense drought and continuing...
Categories: Publication;
Types: Citation
Reproduction is a key component of ecological resilience in forest ecosystems, so understanding how seed production is influenced by extreme drought is key to understanding forest recovery trajectories. If trees respond to mortality-inducing drought by preferentially allocating resources for reproduction, the recovery of the stand to pre-drought conditions may be enhanced accordingly. We used a 20-year annual seed capture data set to investigate whether seed production by three tree genera commonly found in the Sierra Nevada (Abies, Pinus, and Calocedrus) was correlated with variation in local weather, which included an extreme drought spanning multiple years. We tested whether average seed production differed during...
Categories: Publication;
Types: Citation
Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations . Our ability to understand and predict changes in the forest carbon cycle--particularly net primary productivity and carbon storage--increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree , in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation)...
|
|
