Leaf litter cover data on 1m x 1m plots from the long-term Small Mammal Exclusion Study (SMES) at Jornada Basin LTER, 1995-2015

This data package contains leaf litter cover data from plots with various levels of herbivore exclusion on the Jornada Experimental Range. 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 the grassland 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. Because grazing cattle are excluded from the entire creosote site, only three replicate experimental blocks were randomly located there including a) all mammalian herbivores, including lagomorphs, and rodents, b) lagomorphs only, and c) 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 total percent cover of leaf litter in each quadrat was estimated by summing the percent of each 10 cm square within a quadrat (including 100 10-cm squares) containing leaf litter (See methods for a detailed explanation). After 2005, sampling frequency changed to every 5 years. This study is ongoing. 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=210086004 Webpage with information and links to data files for download

本数据包包含来自 Jornada 实验站不同放牧排斥程度样地的凋落物覆盖数据。研究站点于 1995 年设立，其中一处位于黑格兰玛草地，另一处位于漆树灌木丛，旨在对比不同植被类型之间放牧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）设立了平行研究。每个研究站点的面积为 1 公里乘以 0.5 公里。在草地研究站点随机布置了四个重复的实验小区，以测量植被对包括以下排斥处理的响应：a) 所有哺乳动物放牧动物，包括牛、兔形目动物和啮齿动物，b) 仅兔形目动物和牛，c) 仅牛，以及 d) 所有放牧动物均可进入的控制区。由于放牧牛被排除在整个漆树站点之外，因此在此处随机布置了三个重复的实验小区，包括 a) 所有哺乳动物放牧动物，包括兔形目动物和啮齿动物，b) 仅兔形目动物，以及 c) 所有放牧动物均可进入的控制区。在每个样地内，按照系统布局的 6x6 点网格，以 5.8 米的间隔定位了 36 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 年至 2005 年的每年春季和秋季，通过将样方内每个 10 厘米平方（包括 100 个 10 厘米平方）含有凋落物的百分比相加来估算每个样方中凋落物的总覆盖率（详见方法部分详细说明）。2005 年之后，采样频率改为每 5 年一次。该研究仍在进行中。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-jrn&identifier=210086004，网页包含信息以及数据文件的下载链接。