SGS-LTER Effects of grazing on ecosystem structure and function (GZTX): Vegetation density on the Central Plains Experimental Range, Nunn, Colorado, USA 1992-2008, ARS Study Number 32

This data package was produced by researchers working on the Shortgrass Steppe Long Term Ecological Research (SGS-LTER) Project, administered at Colorado State University. Long-term datasets and background information (proposals, reports, photographs, etc.) on the SGS-LTER project are contained in a comprehensive project collection within the Digital Collections of Colorado (http://digitool.library.colostate.edu/R/?func=collections&collection_id=3429). The data table and associated metadata document, which is generated in Ecological Metadata Language, may be available through other repositories serving the ecological research community and represent components of the larger SGS-LTER project collection.
When the CPER was established in 1939, researchers constructed a .5-1 ha grazing exclosure in each of the pastures. These areas have remained protected from grazing for the past 70 years. The remaining areas have been grazed for the past 20+ years. This collection of pastures and exclosures provided an extraordinary opportunity to reinitiate grazing and protection, and evaluate the balance between degradation and aggradation. We proposed to rearrange fences and expose areas to grazing that have been protected for 50 years, and protect areas from grazing that had been grazed for 50 years. The combinations of grazing conditions were: 1. Long-term protection 2. Long-term grazing (moderate) 3. 50 years of protection followed by grazing 4. 50 years of grazing followed by protection Net primary production, nitrogen dynamics, cattle utilization, and community dynamics of vegetation were measured. Additional information and referenced materials can be found: http://hdl.handle.net/10217/85596. Resources in this dataset:Resource Title: Website Pointer to html file. File Name: Web Page, url: https://portal.edirepository.org/nis/mapbrowse?scope=knb-lter-sgs&identifier=529 Webpage with information and links to data files for download

此数据集由致力于短草草原长期生态研究项目（SGS-LTER）的研究者们编制，该项目由科罗拉多州立大学管理。关于SGS-LTER项目的长期数据集及相关背景资料（如提案、报告、照片等）均收录在科罗拉多州数字收藏馆的全面项目集合中（http://digitool.library.colostate.edu/R/?func=collections&collection_id=3429）。数据表格及其关联的元数据文档，采用生态元数据语言编制，可能通过服务于生态研究社区的其它存储库获取，并构成SGS-LTER项目集合的组成部分。

自1939年成立CPER以来，研究人员在每个牧场上构建了0.5-1公顷的放牧隔离区。这些区域在过去70年间一直免受放牧的影响。剩余区域在过去20多年中一直处于放牧状态。这些牧场的放牧隔离区组合为重新启动放牧和保护措施提供了非凡的机会，并评估了退化和堆积之间的平衡。我们提议重新安排围栏，将受保护50年的区域暴露于放牧，并将放牧50年的区域进行保护。放牧条件组合包括：1. 长期保护 2. 长期放牧（适度）3. 50年保护后放牧 4. 50年放牧后保护。对净初级生产、氮循环、牲畜利用和植被群落动态进行了测量。更多信息和参考材料可查阅：http://hdl.handle.net/10217/85596。本数据集包含的资源：
资源标题：指向HTML文件的网站指针。文件名：网页，网址：https://portal.edirepository.org/nis/mapbrowse?scope=knb-lter-sgs&identifier=529，包含信息和数据文件的下载链接。