Description
Enregistrements de données
Les données de cette ressource données d'échantillonnage ont été publiées sous forme d'une Archive Darwin Core (Darwin Core Archive ou DwC-A), le format standard pour partager des données de biodiversité en tant qu'ensemble d'un ou plusieurs tableurs de données. Le tableur de données du cœur de standard (core) contient 822 enregistrements.
2 tableurs de données d'extension existent également. Un enregistrement d'extension fournit des informations supplémentaires sur un enregistrement du cœur de standard (core). Le nombre d'enregistrements dans chaque tableur de données d'extension est illustré ci-dessous.
Cet IPT archive les données et sert donc de dépôt de données. Les données et métadonnées de la ressource sont disponibles pour téléchargement dans la section téléchargements. Le tableau des versions liste les autres versions de chaque ressource rendues disponibles de façon publique et permet de tracer les modifications apportées à la ressource au fil du temps.
Versions
Le tableau ci-dessous n'affiche que les versions publiées de la ressource accessibles publiquement.
Comment citer
Les chercheurs doivent citer cette ressource comme suit:
Levy R, DePrenger-Levin M (2024). Life History and Demography of Astragalus microcymbus. Version 1.0. Kathryn Kalmbach Herbarium (Denver Botanic Gardens). Samplingevent dataset. https://ipt.vertnet.org/resource?r=dbg_astragalus-microcymbus_demography&v=1.0
Droits
Les chercheurs doivent respecter la déclaration de droits suivante:
L’éditeur et détenteur des droits de cette ressource est Kathryn Kalmbach Herbarium (Denver Botanic Gardens). En vertu de la loi, l'éditeur a abandonné ses droits par rapport à ces données et les a dédié au Domaine Public (CC0 1.0). Les utilisateurs peuvent copier, modifier, distribuer et utiliser ces travaux, incluant des utilisations commerciales, sans aucune restriction.
Enregistrement GBIF
Cette ressource a été enregistrée sur le portail GBIF, et possède l'UUID GBIF suivante : bf6e2cd9-ff4d-465a-a5f0-3018c5495b3f. Kathryn Kalmbach Herbarium (Denver Botanic Gardens) publie cette ressource, et est enregistré dans le GBIF comme éditeur de données avec l'approbation du GBIF-US.
Mots-clé
Samplingevent; Astragalus microcymbus; sagebrush steppe; demography; narrow endemic; long term monitoring; Observation
Contacts
- Créateur
- Scientific Data Manager
https://orcid.org/https://orcid.org/0000-0002-4401-1380
- Chercheur Principal
- Population Biology Research Associate
- Personne De Contact
- Associate Director of Climate Resilience
- Créateur
- Chercheur Principal
Couverture géographique
Data were recorded at 6 six sites in Gunnison County in western Colorado, United States. Sites 05, 15, 19, and 26 are located in the South Beaver Creek watershed, while sites 01 and 02 are located in the Cebolla Creek watershed. All sites are in the Gunnison River Basin within the Colorado River Basin and are on land owned and maintained by the United States Bureau of Land Management, at the time of the study.
| Enveloppe géographique | Sud Ouest [38,245, -107,358], Nord Est [38,548, -106,809] |
|---|
Couverture taxonomique
This resource provides observations and measurements of Astragalus microcymbus, a member of the family Fabaceae.
| Species | Astragalus microcymbus (skiff milkvetch) |
|---|
Couverture temporelle
| Date de début / Date de fin | 1995-07-20 / 2024-07-25 |
|---|
Données sur le projet
Astragalus microcymbus, the skiff milkvetch, is a perennial forb endemic to Gunnison and Saguache counties in Colorado, United States. In 1995 Denver Botanic Gardens scientists began monitoring individual A. microcymbus plants to track longevity and reproductive rates, ultimately recording plant length, reproductive condition, life stage, and herbivory damage on an annual basis. This resource provides occurrence and measurement data in the form of a sampling event dataset.
| Titre | Life History and Demography of Astragalus microcymbus |
|---|---|
| Financement | Funding for this project was provided by the Colorado State Office of the Bureau of Land Management and Denver Botanic Gardens. |
| Description du domaine d'étude / de recherche | The study area occurs within the rolling hills of sagebrush steppe or open juniper-sagebrush habitat in western Colorado, United States of America. Sites sit within the Gunnison River Valley at approximately 2500 meters above sea level where the climate is arid with hot summers and cold winters. Disturbances include cattle grazing and recreational trails. Associated plant taxa include Purshia tridentata,Yucca harrimaniae, Artemisia frigida, Chaenactis, Penstemon caespitosa, Symphoricarpos, Sedum lanceolatum, Phlox, Hesperia comata, Castilleja, and Poa. |
| Description du design | The overall goal of this project is to better understand population trends and provide conservation recommendations for A. microcymbus. Specifically, the study aims to learn about the life history of this rare species with a special emphasis on prolonged dormancy and reproductive potential, elucidate the population trends and potential connections to climate, and understand what management actions will best support the long-term survival of this species. In 1995 five sites were randomly selected from 42 known colonies located on Bureau of Land Management lands in the South Beaver Creek drainage. Only one plot was established within one of these initial sites (40) and the site was subsequently dropped in 1996. Within each site, up to 500 individual plants with stem length greater than 30 centimeters were marked. Marked plants were then randomly selected to serve as center points of 3-meter radius circular plots. To increase sample size, additional plots were added in 1996 and 2004. Additional populations were confirmed on public lands in the Cebolla Creek drainage in 2011. Additional sites and plots in the Cebolla Creek drainage were added in 2014 for a total of 30 plots across the study. All detectable A. microcymbus plants were marked with a permanent tag 10 centimeters north of each plant. New plants found each year are given a new tag or associated with an existing tag if an existing tag is within ca. 1-meter of the plant. Plots were visited annually with the exception of 2013 - 2015 when plots were additionally visited approximately every two weeks to every month within a growing season. These additional visits served to observe the timing of germination and understand rates of prolonged dormancy. Length of the longest stem, flowering status, number of fruits, and if any animal herbivory was present were measured and recorded for all detectable plants at the time of the survey. If a plant is not present it is marked as dead. Due to concerns about the amount of herbivory and its potential to reduce reproductive fitness, fencing was installed in 2006 around plots 608 and 609 from site 05, 238 and 480 from site 26 and in 2007 around plots 300 and 512 from site 19. Fencing consisted of approximately 20 meters of chicken wire, standing over 3 feet tall, wrapped around t-stakes surrounding the plot. The chicken wire was folded outward from the plot, flush against the ground to discourage burrowing animals. |
Les personnes impliquées dans le projet:
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
- Fournisseur De Contenu
Méthodes d'échantillonnage
Plots were surveyed once per year, except for 2013, 2014, and 2015 when plots were sampled multiple times from April to October. Astragalus microcymbus is a perennial forb with stems that die back to the ground each year. Surveys were conducted in late July and early August when above ground growth has assuredly occurred or begun, if the individual plant was not undergoing dormancy. Plots were circular with a 3-meter radius. Each plot was marked with a steel bar protruding from the ground at the center. All A. microcymbus plants that fell within the 3-meter radius were measured. Each A. microcymbus plant was assigned a numbered metal tag that was attached to a nail which was placed in the soil 10 centimeters north of the associated plant. The distance and cardinal direction from the center steel rod to the tag was recorded to aid in locating plants and confirming their identity. Previously undocumented plants found within plots were assigned a new tag. If new plants were within 1-meter of an existing tag, they were assigned that same tag number but with a sequential sub-number. For example, 2 previously undocumented plants within 1-meter of tag 815, would be recorded as 815.01 and 815.02. The distance in centimeters and the cardinal direction of the tag from the plant were then recorded. For each plant observed in the plot, the length of the longest stem, presence or absence of reproductive structures (flowers or fruits), the number of fruits on the plant, if evidence of animal herbivory was observed, and if possible whether the herbivory was from a mammal or insect. If an expected plant was not observed, it was marked as dead. However, a plant could lack a detectable signal (i.e. lack above ground growth), it could be hidden in surrounding vegetation, or missed due to herbivory. From these data, three and four stage life cycles were built for population viability analyses. In the four stage life cycle, individual plants were classified into: (1) seedling: the first year an individual is detected; (2) vegetative: an individual observed for two or more years that contains no reproductive structures; (3) reproductive: an individual observed for two or more years that has reproductive structures; and (4) dormant: an individual that was observed in a preceding and later year, but not in the current year in question. The three-stage life cycle does not include a seedling stage.
| Etendue de l'étude | Data were collected in 1995 through 2024. Circular plots were surveyed annually in late July and early August. Sixteen plots were established in 1995 within the 4 original sites (05, 15, 19, and 26). In 1996 one plot each was added to sites 19 and 26 and in 2004 1 plot was added to site 26. Two new sites, 01 and 02, were added to the study in 2014 with 5 and 6 plots, respectively. However, one plot at site 02 was dropped in 2020 after an unknown party removed most of the tags from the plot. Within site 01, plots all fell within a 115m x 25 m area, site 02 plots all fell within a 190 m x 150 m area , site 05 plots all fell within a 37 m x 7 m area, site 15 plots all fell within a 17 m x 13 m area, site 19 plots all fell within a 78 m x 24 m area, and site 26 plots all fell within an 85 m x 16 m area. Each plot has a permanent steel bar installed in the center and extend outward to a 3-meter radius. |
|---|---|
| Contrôle qualité | Data are assessed for quality as part of the digitization process. Data are transcribed from printed field sheets into a .csv template file. The data file is then imported into a web-based application developed specifically for this project. After import, a quality assurance workflow is initiated, checking the data for outliers in plant length (greater than 1 meter), correcting mismatches between a count of fruit but a status of non-reproductive, and confirming that new plants are correctly associated with the appropriate tag. |
Description des étapes de la méthode:
- 1. Upon arriving at a site, plots were located with detailed driving and hiking directions with hand drawn maps. Once GPS units became available, sites were located with the aid of a GPS unit (most recently a field tablet equipped with the ArcGIS Field Maps application) and a metal detector. Each plot was marked with a steel bar protruding from the ground at the center.
- 2. Plants are located using pre-printed data sheets. Data sheets list all previously surveyed plants and their assigned tag number, as well as the tag’s location relative to the center steel bar, the plant’s location relative to the tag, and each plant’s measurements from the previous three years.
- 3. Meter tapes are used to reference 3-meters from the center of each circular plot. The plot is scanned for plants with above ground growth. When a plant is found, the nearest tag is checked on the data sheet to confirm if the plant was previously marked. The tag’s location relative to the associated plant is used to identify the plant that is to be measured. If no mark (i.e. tag with appropriate distance and direction) exists, a new tag or new mark off an existing tag is added for the new plant. The distance and direction from the center steel bar is recorded for new tags and the distance from the plant to the tag is recorded for each new plant. After a visual scan of the plot is complete, if a plant was measured with above ground growth in a previous year but was not found in the current year, the distance and direction from the center steel bar to the tag is used to locate the tag and search for the missing plant. A metal detector is used to search for tags that have become buried to limit soil disturbance. Tags that have been displaced are relocated according to the distance and direction from the center metal stake.
- 4. Once the plant and corresponding tag are confirmed or added, the following measurements are taken: a. Length of the longest stem. Measure in centimeters from the ground at the base of the stem to the tip of the stem, by extending the stem as long as it will go. b. Flowering status. Does the plant currently have flowers or has the plant produced flowers this season that are now fruit? Record “1” for yes or “0” for no. c. Number of fruit present on all stems. Using the tally counter tool, count every fruit present on every stem of the plant. We note in the comments field if fruit have fallen before they can be counted. d. Evidence of herbivory. Record if the plant was browsed upon in some form. Record “1” for yes or “0” for no. e. Comments. If the plant exhibits evidence of herbivory, indicate if it is due to mammal or insect. Evidence of insect herbivory include aphids on the leaves or stems or a girdled stem with the broken stem nearby. Mammal herbivory may appear as a slanted cut to the stem with no stem remaining. Add any other comments about the plant. Note “tag lost” if the tag cannot be found or ‘replaced’ if the tag was found out of the ground.
- 5. Repeat for each plant in the plot. a. If there is a plant that does not have a corresponding tag, such as a new seedling, add a new tag and record the tag and plant locations as well as the measurements or add a new record to an existing tag and the distance and direction of the new plant to the existing tag. b. If a plant is not found, mark it as dead.
Citations bibliographiques
- Barneby,RC (1964): Atlas of North American Astragalus. Memoirs of the New York Botanical Garden 13, 192-193.
- DePrenger-Levin, Michelle & Neale, Jennifer & Grant III, Thomas & Dawson, Carol & Baytok, Yasemin. (2013). Life History and Demography of Astragalus microcymbus Barneby (Fabaceae). Natural Areas Journal. 33. 264-275. 10.3375/043.033.0305. 10.3375/043.033.0305
- U.S. Fish and Wildlife Service. (2010). Endangered and threatened wildlife and plants; 12-month finding on a petition to list Astragalus microcymbus and Astragalus schmolliae as Endangered or Threatened; proposed rule. In Federal Register (Vol. 75, Issue 240). Fish and Wildlife Service.
- U.S. Fish and Wildlife Service. (2014). Endangered and Threatened Wildlife and Plants; Threatened Status for Gunnison Sage-Grouse. In D. of the Interior (Ed.), Federal Register (Vol. 79, Issue 224, pp. 69192–69310). Federal Register.
- U.S. Fish and Wildlife Service. (2019). Endangered and threatened wildlife and plants; Five species not warranted for listing as endangered or threatened species. Federal Register, 69707–69712.
Métadonnées additionnelles
| Remerciements | We thank long-term volunteers Dave Tolen, Lee Cassin, Larry Allison, Mel Preusser, Karen Cleaver, and Harlan Cleaver for their dedication and determined work recording data in the field. |
|---|---|
| Introduction | Astraglaus microcymbus (Fabaceae) is a rare forb endemic to Gunnison and Saguache Counties, Colorado, USA. A study was initiated in 1995 to understand the life history, population dynamics, and management actions needed to conserve this rare and potentially at-risk species. This Bureau of Land Management sensitive species became a candidate on the Endangered Species Act in 2010 due to downward population trends and growing threats from surrounding residential and urban development, invasive species, and habitat degradation. This species was thought to exhibit whole plant prolonged dormancy with no above ground growth for an entire growing season. Dormancy has been shown to buffer plants from fitness loss due to harsh environmental conditions. However, after three seasons of multiple visits throughout the growing season, it appears that Astragalus microcymbus do not remain dormant as perennating roots for the entire season and instead periodically lack above ground growth throughout the season. Therefore, there are multiple ways to use the data to inform population dynamics. Traditional matrix population models can be used for population viability analyses with two aboveground stages (vegetative, reproductive) and one stage that lacks an aboveground signal (dormant). However, dormancy can also be treated as a cause of missed detection. In this case, mark-recapture models can be used to estimate population dynamics while accounting for imperfect detection. After an initial decline in population density over the first 10 years of this study, populations appear to be stable. However, warmer conditions are predicted as is a shift in the timing of precipitation. Winter precipitation and summer temperatures drive survival and reproduction. Survival and fruit production increase with higher winter precipitation but are reduced by warmer summer temperatures. As temperatures warm and if snowpack either declines or melts earlier in the year, individual fitness and population sizes may decline. |
| Premiers pas | This dataset contains three files; event, occurrence, and extendedMeasurementOrFact. Each event represents either a visit to a site or the survey of a plot within a site. Parent events refer to the visit to a site for the related plot survey. Locations have been obscured to protect sensitive species and habitats. Occurrences represent each observation of the focal species, Astragalus microcymbus within the study plots. Measurements or facts consist of the number of fruits counted on each plant observed, the length of of the longest stem of each plant observed, and if herbivorous browsing was detected on each observed plant. |
| Description de la fréquence de mise à jour | New data are recorded annually. Denver Botanic Gardens aims to publish new data as they become available. |
| Identifiants alternatifs | https://ipt.vertnet.org/resource?r=dbg_astragalus-microcymbus_demography |