Cryptogam crust data from the long-term Small Mammal Exclosure Study (SMES) at Jornada Basin LTER, 1995-2005

This data package contains cryptogam cover data from plots with various levels of herbivore exclusion on Jornada Experimental Range (JER) and Chihuahuan Desert Rangeland Research Center (CDRRC) lands. Study sites were established in 1995; one in black grama grassland and the other in creosotebush shrubland to compare the impact of herbivores on ecosystem processes between these vegetation types. Parallel studies were established at the Sevilleta LTER site (New Mexico, USA) and Mapimi Biosphere Reserve (Durango, Mexico). Each study site is 1 km by 0.5 km in area. Four replicate experimental blocks were randomly located at each study site to measure vegetation responses using exclusion treatments including a) all mammalian herbivores, including cattle, lagomorphs, and rodents, b) lagomorphs and cattle only, c) cattle only, and d) control accessible to all herbivores. Thirty-six sampling points were positioned at 5.8-meter intervals on a systematically located 6 by 6 point grid within each plot. A permanent one-meter by one-meter vegetation measurement quadrat is located at each of the 36 points. Each year in spring and fall from 1995-2005, the percent of a quadrat covered in cryptogams was estimated by summing the percent of each 10 cm square within a quadrat (including 100 10-cm squares) containing cryptogams (See methods for a detailed explanation). Cryptogams (biological soil crusts) include lichens, algae, cyanobacteria, and moss. This study is complete. 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-jrn&identifier=210086003 Webpage with information and links to data files for download

本数据包包含了来自 Jornada Experimental Range (JER) 和 Chihuahuan Desert Rangeland Research Center (CDRRC) 土地上的不同食草动物排斥级别地块的隐花植物覆盖数据。研究站点自1995年起设立；一处位于黑格兰姆草原，另一处位于松脂灌木丛草地，以比较不同植被类型之间食草动物对生态系统过程的影响。在 Sevilleta LTER 站点（美国新墨西哥州）和 Mapimi 生物圈保护区（墨西哥杜兰戈州）也设立了并行研究。每个研究站点的面积均为1公里乘以0.5公里。在每个研究站点随机布置了四个重复的实验地块，用以测量植被对排斥处理的响应，包括：a) 所有哺乳动物食草动物，包括牛、兔形目动物和啮齿类动物，b) 仅兔形目动物和牛，c) 仅牛，以及d) 可供所有食草动物进入的控制组。在每个地块内，按照6乘以6的点阵网格，以5.8米的间隔设置了三十六个采样点。在每个采样点处，放置了一个永久性的1米乘以1米的植被测量样方。从1995年到2005年的春季和秋季每年，通过计算样方内含有隐花植物（包括生物土壤结皮，如地衣、藻类、蓝细菌和苔藓）的百分比（详见方法部分）来估算每个样方被覆盖的百分比。隐花植物包括地衣、藻类、蓝细菌和苔藓。本研究已完成。本数据集中的资源包括：资源标题：网站指针至html文件，文件名：网页，url：https://portal.edirepository.org/nis/mapbrowse?scope=knb-lter-jrn&identifier=210086003，网页包含信息和数据文件下载链接。