USGS Submissions

Boreal and Arctic regions of Alaska are warming more rapidly than other parts of the world, resulting in the thawing of permafrost, higher rates and severity of disturbance events, and the expansion of tree and shrub areas. Together, these changes are having a profound impact on ecosystem structure and function.

Large-scale plant productivity in coastal marshes needs to be quantified to understand marsh resilience to sea-level rise, to help define eligibility for carbon offset credits, and to monitor impacts from land use, eutrophication, and contamination. Remote monitoring of aboveground biomass of emergent wetland vegetation will help address this need. Differences in sensor spatial resolution, bandwidth, temporal frequency, and cost constrain the accuracy of biomass maps produced for management applications.

Detailed information on the extent and distribution of marsh vegetation zones throughout the Texas coast has been historically unavailable.  To address this data gap, the USGS NWRC in collaboration with others, produced a seamless and standardized classification of marsh vegetation types indicative of salinity zones (i.e., fresh, intermediate, brackish, and saline) along the Texas coast from Corpus Christi Bay to the Sabine River.  Decision tree analyses were used to classify marsh types from

Coastal marshes depend on belowground biomass of roots and rhizomes to contribute to peat and soil organic carbon, accrete soil, and alleviate flooding as sea level rises. Within a freshwater wetland impoundment receiving minimal sediments, we used experimental plots to explore growth models for a common freshwater macrophyte, Schoenoplectus acutus (S. acutus). We used nitrogen (N)-addition and control plots (4 each) to test whether remotely sensed vegetation indices could predict leaf N concentration, root:shoot ratios, and belowground biomass of S. acutus.

Monitoring productivity in coastal wetlands is important due to their high carbon sequestration rates and potential role in climate change mitigation. We tested agricultural- and forest-based methods for estimating the fraction of absorbed photosynthetically active radiation (f APAR) in a restored, managed wetland with a dense litter layer of non-photosynthetic vegetation. FAPAR is a key parameter for modelling gross primary productivity (GPP).

The USGS UMESC is using state-of-the-art three-dimensional mapping technologies and high-resolution digital aerial photograph to map Crane Creek of the Ottawa National Wildlife Refuge (ONWR), near Oak Harbor, Ohio.  Through extensive partnerships with the USFWS and Ducks Unlimited, a water control structure was constructed at ONWR to restore the hydrologic connection between a 99-acre coastal wetland and Lake Erie waters for the first time in nearly 40 years.

Using high-resolution aerial photography (provided by Fort A.P. Hill), NWRC will conduct comprehensive mapping of wetland areas for the U.S. Army Fort A.P. Hill regional training center in Virginia.  The NWRC will use 2013 imagery to update existing wetland habitats throughout the entire base. Fort A.P.

The increasing societal need for renewable energy from the agricultural sector offers new opportunities and challenges as we redefine ecosystem goods and services in view of sustainable land use and management under changing climates.  Corn stover is the combination of all aboveground components of the corn plant, except for the corn seeds. In other words, stover is the residue that consists of stalk, leaves, husks, and cobs of corn remaining in the field following the harvest of corn seeds. Corn stover is a common agricultural product

This project investigates the geologic framework of basins and adjoining mountain flanks along the Rio Grande Rift in different areas of the Southwestern U.S. to provide information on critical groundwater aquifers, hazards (seismic, subsidence, landslide), climate change rates, and resources (minerals, energy).  We are using lidar, aeromagnetic and gravity data, and Landsat imagery to identify and map bedrock and surficial features and landforms to address these issues.

The USGS Astrogeology Science Center (Astrogeology) is currently supporting five missions that have visited or will visit either an asteroid or a dwarf planet: Dawn, New Horizons, Rosetta, Hayabusa, and OSIRIS-REx.  The Dawn mission is the current NASA spacecraft in the main asteroid belt and is en route to the largest asteroid, the dwarf planet Ceres. The Dawn spacecraft had previously been in orbit around the second largest asteroid, 4 Vesta.