Geology topics

Robert K. Peet

Publications and source records attributed to Robert K. Peet.

4 recordsLinked to original sources

USGS2023

SPCIS: Standardized Plant Community with Introduced Status database

The movement of plant species across the globe exposes native communities to new species introductions. While introductions are pervasive, two aspects of variability underlie patterns and processes of biological invasions at macroecological scales. First, only a portion of introduced species become invaders capable of substantially impacting ecosystems. Second, species that do become invasive at one location may not be invasive in others; impacts depend on invader abundance and recipient species and conditions. Accounting for these phenomena is essential to accurately understand the patterns of plant invasion and explain the idiosyncratic results reflected in the literature on biological invasions. The lack of community-level richness and the abundance of data spanning broad scales and environmental conditions have until now hindered our understanding of invasions at a macroecological scale. To address this limitation, we leveraged quantitative surveys of plant communities in the USA and integrated and harmonized nine datasets into the Standardized Plant Community with Introduced Status (SPCIS) database. The database contains 14,056 unique taxa identified within 83,391 sampling units, of which 52.6% have at least one introduced species. The SPCIS database includes comparable information on plant species occurrence, abundance, and native status across the 50 U.S. States and Puerto Rico. SPCIS can be used to answer macro-scale questions about native plant communities and interactions with invasive plants. There are no copyright restrictions on the data, and we ask the users of this dataset to cite this paper, the respective paper(s) corresponding to the dataset sampling design (all references are provided in Data S1: Metadata S1: Class II-B-2), and the references described in Data S1: Metadata S1: Class III-B-4 as applicable to the dataset being utilized.

Ecology↗

USGS2019

The plant diversity sampling design for The National Ecological Observatory Network

The National Ecological Observatory Network (NEON) is designed to facilitate an understanding of the impact of environmental change on ecological systems. Observations of plant diversity—responsive to changes in climate, disturbance, and land use, and ecologically linked to soil, biogeochemistry, and organisms—result in NEON data products that cross a range of organizational levels. Collections include samples of plant tissue to enable investigations of genetics, plot‐based observations of incidence and cover of native and non‐native species, observations of plant functional traits, archived vouchers of plants, and remote sensing airborne observations. Spatially integrating many ecological observations allows a description of the relationship of plant diversity to climate, land use, organisms, and substrates. Repeating the observations over decades and across the United States will iteratively improve our understanding of those relationships and allow for the testing of system‐level hypotheses as well as the development of predictions of future conditions.

Ecosphere↗

USGS2015

Patterns of floodplain sediment deposition along the regulated lower Roanoke River, North Carolina: annual, decadal, centennial scales

The lower Roanoke River on the Coastal Plain of North Carolina is not embayed and maintains a floodplain that is among the largest on the mid-Atlantic Coast. This floodplain has been impacted by substantial aggradation in response to upstream colonial and post-colonial agriculture between the mid-eighteenth and mid-nineteenth centuries. Additionally, since the mid-twentieth century stream flow has been regulated by a series of high dams. We used artificial markers (clay pads), tree-ring (dendrogeomorphic) techniques, and pollen analyses to document sedimentation rates/amounts over short-, intermediate-, and long-term temporal scales, respectively. These analyses occurred along 58 transects at 378 stations throughout the lower river floodplain from near the Fall Line to the Albemarle Sound. Present sediment deposition rates ranged from 0.5 to 3.4 mm/y and 0.3 to 5.9 mm/y from clay pad and dendrogeomorphic analyses, respectively. Deposition rates systematically increased from upstream (high banks and floodplain) to downstream (low banks) reaches, except the lowest reaches. Conversely, legacy sediment deposition (A.D. 1725 to 1850) ranged from 5 to about 40 mm/y, downstream to upstream, respectively, and is apparently responsible for high banks upstream and large/wide levees along some of the middle stream reaches. Dam operations have selectively reduced levee deposition while facilitating continued backswamp deposition. A GIS-based model predicts 453,000 Mg of sediment is trapped annually on the floodplain and that little watershed-derived sediment reaches the Albemarle Sound. Nearly all sediment in transport and deposited is derived from the channel bed and banks. Legacy deposits (sources) and regulated discharges affect most aspects of present fluvial sedimentation dynamics. The lower river reflects complex relaxation conditions following both major human alterations, yet continues to provide the ecosystem service of sediment trapping.

North Carolina↗

USGS2015

How a national vegetation classification can help ecological research and management

The elegance of classification lies in its ability to compile and systematize various terminological conventions and masses of information that are unattainable during typical research projects. Imagine a discipline without standards for collection, analysis, and interpretation; unfortunately, that describes much of 20th-century vegetation ecology. With differing methods, how do we assess community dynamics over decades, much less centuries? How do we compare plant communities from different areas? The need for a widely applied vegetation classification has long been clear. Now imagine a multi-decade effort to assimilate hundreds of disparate vegetation classifications into one common classification for the US. In this letter, we introduce the US National Vegetation Classification (USNVC; www.usnvc.org) as a powerful tool for research and conservation, analogous to the argument made by Schimel and Chadwick (2013) for soils. The USNVC provides a national framework to classify and describe vegetation; here we describe the USNVC and offer brief examples of its efficacy.

Frontiers in Ecology and the Environment↗