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  • How do plants and animals respond to environmental disturbances and changes in climate?

  • Rising average annual temperatures or changes in rainfall patterns

  • may influence the timing of flowering for plant species in a region.

  • These changes can have a ripple effect on interacting species in the ecosystem,

  • like pollinators that depend on the flowers and fruit.

  • A change in a species trait can be a bellwether for changes in the biodiversity of the ecosystem as a whole.

  • Scientists from the National Ecological Observatory Network, or NEON,

  • are collecting regular observations of rainfall, plants, insects, birds, and much more

  • at field sites across the United States as part of an ambitious program

  • designed to provide researchers with unprecedented amounts of ecological data

  • to better study our ecosystems and forecasts how they will change over time.

  • From monitoring population and community dynamics of organisms,

  • to measuring fluxes of carbon, water, and energy between terrestrial ecosystems and the atmosphere,

  • to mapping changes in land surface characteristics,

  • the National Science Foundation's NEON collects data at 47 terrestrial field sites across the

  • United States to gain a comprehensive picture of ecosystem function.

  • Terrestrial sites are also co-located with NEON's freshwater aquatic sites, whenever possible

  • to enable the complimentary study of aquatic and terrestrial ecosystems.

  • Terrestrial field site characteristics and size vary considerably,

  • from one of the smallest field sites at

  • Lajas Experimental Research Station at only 3.95 square kilometers,

  • to the much larger Santa Rita Experimental Range field site,

  • that spans an impressive 215 square kilometers.

  • NEON uses three standardized and complementary data collection systems.

  • Observational field sampling, automated instruments, and airborne remote sensing.

  • All three systems are standardized across field sites,

  • while automated instruments and remote sensing are routinely calibrated and tested.

  • This all contributes to a more accurate and detailed picture of ecosystem function

  • and change on a local, regional, and continental scale.

  • To get a better idea of this let's walk through the integrated spatial sampling design of a terrestrial field site.

  • In the dominant vegetation, a meteorological tower rises above the plant canopy.

  • This tower collects measurements of weather and climate including fluxes of carbon, water, and

  • energy between terrestrial ecosystems and the atmosphere.

  • At each tower an upland area captured by the atmospheric measurements is defined as the tower air shed.

  • Where there is more than one prevailing wind direction there can be a secondary air shed too.

  • Phenocams mounted on the top and bottom of the tower and

  • typically facing north, collect time-lapse photos of

  • the nearby environment throughout the year.

  • Over time this imagery data will reveal

  • trends related to the greening of vegetation at each site.

  • An array of five soil plots is installed within the tower air shed.

  • Sensors in the soil array collect above-ground meteorological data and

  • below ground soil measurements to

  • allow for research on biogeochemical processes.

  • Soil data are collected at multiple depths and

  • include temperature, soil moisture, and CO2 concentration.

  • NEON establishes observational sampling plots throughout the tower air shed and

  • distributed observational sampling plots stratified across the vegetation types of the site.

  • Using standardized protocols NEON scientists collect observations of

  • soil microbes, ground beetles, mosquitoes, ticks, plants, birds, and small mammals at these plots.

  • These data include individual traits, population dynamics,

  • and the composition of organismal communities.

  • A subset of organisms are sampled for pathogens and DNA sequences.

  • NEON field scientists also collect biogeochemical data of plants and soils.

  • In addition to observational sampling, NEON archives

  • thousands of specimens and samples from each site every year.

  • This includes biological, genomic, and geological samples that are stored in the NEON Biorepository,

  • and are available for scientists upon request.

  • NEON also takes to the skies conducting airborne remote sensing surveys.

  • Using discrete and waveform lidar, spectrometry data, and high-resolution

  • digital camera images, NEON scientists map the land surface of each field site

  • providing information about vegetation composition, chemistry, and structure.

  • NEON's standardized methods and collection systems allow for users to

  • compare data within a single field site and across multiple field sites to

  • answer more complex ecosystem questions.

  • For example, using NEON data we can study

  • the changing characteristics and composition of mosquito populations at a

  • field site in relation to meteorological data and remote sensing derived

  • vegetation biomass maps.

  • We can then apply these data to how mosquito

  • populations are moving between sites.

  • This will result in improving our

  • ability to detect and predict the movement of mosquito species into new ecosystems.

  • So from the sky down into the soil, NEON is collecting a wide variety

  • of ecological data at different spatial and temporal scales.

  • Automated measurements happen every second of the day in the tower air shed.

  • Weekly field sampling covers a much broader area and

  • NEON's annual remote sensing surveys collect landscape scale data.

  • Visit NEONScience dot org to learn more.

How do plants and animals respond to environmental disturbances and changes in climate?

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NEON陆地野外站点的空间采样设计(The Spatial Sampling Design of NEON Terrestrial Field Sites)

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    joey joey 發佈於 2021 年 05 月 24 日
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