Treesearch

We evaluated impacts of prescribed burns on water quality by performing field sampling on adjacent first-order watersheds (Santee Experimental Forest, South Carolina), where one of the watersheds underwent a prescribed burn in 2016. We measured water quality parameters [dissolved organic carbon (DOC), nitrogen species, UV254 absorbance, and disinfection byproduct formation potential during chlorination and chloramination] before and after the burn. Using ultra-high-resolution mass spectrometry, we characterized dissolved organic matter features in raw water collected during the first...

Live woody vegetation is the largest reservoir of biomass carbon, with its restoration considered one of the most effective natural climate solutions. However, terrestrial carbon fluxes remain the largest uncertainty in the global carbon cycle. Here, we develop spatially explicit estimates of carbon stock changes of live woody biomass from 2000 to 2019 using measurements from ground, air, and space. We show that live biomass has removed 4.9 to 5.5 PgC year−1 from the atmosphere, offsetting 4.6 ± 0.1 PgC year−1 of gross emissions from disturbances and adding substantially (0.23 to 0.88 PgC...

Coarse woody debris (CWD) is an important component in forests, hosting a variety of organisms that have critical roles in nutrient cycling and carbon (C) storage. We developed a process-based model using literature, field observations, and expert knowledge to assess woody debris decomposition in forests and the movement of wood C into the soil and atmosphere. The sensitivity analysis was conducted against the primary ecological drivers (wood properties and ambient conditions) used as model inputs. The analysis used eighty-nine climate datasets from North America, from tropical (14.2˚ N)...

Mangroves are recognized for their valued ecosystem services to coastal areas, and the functional linkages between those services and ecosystem carbon stocks have been established. However, spatially explicit inventories are necessary to facilitate management and protection of mangroves, as well as providing a foundation for payment for ecosystem service programs such as REDD+. We conducted an inventory of carbon stocks in mangroves within Pongara National Park (PNP), Gabon using a stratified random sampling design based on forest canopy height derived from TanDEM-X remote sensing data....

The Rothermel fire spread model provides the scientific basis for the US National Fire Danger Rating System (NFDRS) and several other important fire management applications. This study proposes a new perspective of the model that partitions the reaction intensity function and Energy Release Component (ERC) equations as an alternative that simplifies calculations while providing more insight into the temporal variability of the energy release component of fire danger. We compare the theoretical maximum reaction intensities and corresponding ERCs across 1978, 1988 and 2016 NFDRS fuel models...

Natural climate solutions (NCS), a set of land management, conservation and restoration practices aimed at mitigating climate change, have been introduced as cost-effective strategies to increase carbon (C) sequestration in terrestrial ecosystems. Improved forest management (IFM) has been identified as one NCS for working forests with substantial climate change mitigation potential. However, there is a disconnect between the policy and carbon markets context and the scientific evidence for verifiable C benefits. Further, forest soil C—the largest forest C pool—has largely been excluded...

Rangeland managers promoting sustainable use of semiarid ecosystems in the Southwestern U.S. face numerous complex challenges, including invasions by non-native species, the expansion of woody vegetation, altered fire regimes, and drought. These challenges are compounded by uncertainty in how these problems will respond to any changes in climate. Decisions that land managers make today will influence landscapes for decades.

Managing forests has been demonstrated to be an efficient strategy for fragmenting fuels and for reducing fire spread rates and severity. However, large-scale analyses to examine operational aspects of implementing different forest management scenarios to meet fire governance objectives are nonexistent for many Mediterranean countries. In this study we described an optimization framework to build forest management scenarios that leverages fire simulation, forest management, and tradeoff analyses for forest areas in Macedonia, Greece. We demonstrated the framework to evaluate five forest...

Recent, widespread tree mortality in the western U.S. resulting from changes in climate, pathogens, insect activity, and forest management practices has led to concerns for many ecologically and culturally important species. Within conifers, resin-based defenses have long been recognized as a primary defense mechanism against a variety of insects and pathogens. Oleoresin produced by trees contain complex mixtures of terpenoids that have numerous insecticidal and fungicidal properties. Research has also identified links between resin duct characteristics and increased probability of...

After fire, bark beetles pose a significant threat to trees. Resin duct characteristics in trees can increase resistance to bark beetles. However, little is known about how intra- and interspecific variations in resin ducts due to tree characteristics, fire-caused tree injury and life history traits contribute to resistance. In fall 2013, a mixed-stand of Pinus sylvestris and P. nigra was underburned, with some trees subsequently attacked and killed by bark beetles (Ips sexdentatus) during the following two years. We investigated whether inter- or intraspecific differences in constitutive...