Data Paper. Data Paper

File List Each data set has its own file and its own metadata documenting the data collection details and data set structure. <b>Rodents:</b> <i>Data file</i> (see log of corrections)<i>-- </i> Portal_rodents_19772002.csv <i>Metadata -- </i> Portal_rodent_metadata.htm <b>Plants:</b> <i>Data files -- </i> Portal_plant_summer_annual_19831988.csv Portal_plant_summer_perennial_19831988.csv Portal_plant_summer_annual_19892002.csv Portal_plant_summer_perennial_19892002.csv Portal_plant_winter_annual_19831988.csv Portal_plant_winter_perennial_19831988.csv Portal_plant_winter_annual_19892002.csv Portal_plant_winter_perennial_19892002.csv <i>Metadata -- </i> Portal_plant_metadata.htm <b>Ants:</b> <i>Data files -- </i> Portal_ant_colony_19771987.csv Portal_ant_colony_19882002.csv Portal_ant_bait_19882002.csv <i>Metadata -- </i> Portal_ant_metadata.htm <b>Precipitation:</b> <i>Data files -- </i> Portal_precipitation_19801989.csv Portal_precipitation_19892002.csv <i>Metadata --</i> Portal_precipitation_metadata.htm Description Desert ecosystems have long served as model systems in the study of ecological concepts (e.g., competition, resource pulses, top-down/bottom-up dynamics). However, the inherent variability of resource availability in deserts, and hence consumer dynamics, can also make them challenging ecosystems to understand. Study of a Chihuahuan desert ecosystem near Portal, Arizona, began in 1977. At this site, 24 experimental plots were established in 1977 and divided among controls and experimental manipulations. Experimental manipulations over the years include removal of all or some rodent species, all or some ants, seed additions, and various alterations of the annual plant community. While some of these manipulations were discontinued early on, others (i.e., ant and rodent manipulations) have been maintained throughout the study. Monitoring of the composition and abundances of ants, plants, and rodents has occurred continuously on all 24 plots. From 1977–2002, individual-level data on rodents (i.e., species, sex, size, reproductive condition) was collected monthly for each plot. From 1983–2002, the species-level abundances of plants were sampled on permanent quadrats. From 1977–2002, the species-level abundance of ant colonies was recorded for each plot and from 1988–2002 additional information on ant abundances were recorded. Finally, from 1980–2002 we recorded precipitation at the study site. These data have been used in a variety of publications documenting the effects of the experimental manipulations as well as the response of populations and communities to long-term changes in climate and habitat. Sampling is ongoing and this database will be periodically updated. <i>Key words: ants; Chihuahuan Desert; LTREB data; plants; rodents</i>.

<b>文件列表</b> 每个数据集均配有专属数据文件与元数据，用于记录数据采集细节及数据集结构。<br><b>啮齿动物类：</b> <i>数据文件（详见修正日志）：</i>Portal_rodents_19772002.csv <i>元数据：</i>Portal_rodent_metadata.htm<br><b>植物类：</b> <i>数据文件包括：</i>Portal_plant_summer_annual_19831988.csv、Portal_plant_summer_perennial_19831988.csv、Portal_plant_summer_annual_19892002.csv、Portal_plant_summer_perennial_19892002.csv、Portal_plant_winter_annual_19831988.csv、Portal_plant_winter_perennial_19831988.csv、Portal_plant_winter_annual_19892002.csv、Portal_plant_winter_perennial_19892002.csv <i>元数据：</i>Portal_plant_metadata.htm<br><b>蚁类：</b> <i>数据文件包括：</i>Portal_ant_colony_19771987.csv、Portal_ant_colony_19882002.csv、Portal_ant_bait_19882002.csv <i>元数据：</i>Portal_ant_metadata.htm<br><b>降水类：</b> <i>数据文件包括：</i>Portal_precipitation_19801989.csv、Portal_precipitation_19892002.csv <i>元数据：</i>Portal_precipitation_metadata.htm<br><br>荒漠生态系统长期以来均为生态学理论研究的模式系统，相关研究涵盖种间竞争、资源脉冲、自上而下/自下而上动态等经典生态学概念。但荒漠生态系统中资源可获得性的固有变异，进而引发消费者动态的波动，也使得这类生态系统的研究颇具挑战性。<br><br>1977年，研究团队启动了对亚利桑那州波特尔（Portal）附近奇瓦瓦荒漠（Chihuahuan Desert）生态系统的长期研究。该站点于1977年设立24个实验样地，分为对照组与不同实验处理组。多年来开展的实验处理包括：移除全部或部分啮齿动物物种、移除全部或部分蚁类、添加种子，以及对一年生植物群落进行多种形式的改造。部分实验处理在早期便已终止，但蚁类与啮齿动物的移除处理贯穿整个研究周期。<br><br>研究团队持续对全部24个样地中的蚁类、植物与啮齿动物的组成及丰度进行监测。1977年至2002年，研究团队每月对每个样地的啮齿动物采集个体水平数据，涵盖物种、性别、体型及繁殖状态等信息。1983年至2002年，通过永久样方对植物的物种水平丰度进行采样调查。1977年至2002年，研究团队记录了每个样地中蚁群的物种水平丰度；1988年至2002年，额外补充采集蚁类丰度的相关信息。最后，1980年至2002年，研究团队记录了研究站点的降水数据。<br><br>本数据集已被多篇学术出版物使用，用于阐释实验处理的效应，以及种群与群落对气候与栖息地长期变化的响应。当前采样工作仍在持续进行，本数据库将定期更新。<br><br><i>关键词：蚁类；奇瓦瓦荒漠；长期生态研究数据（LTREB，Long-Term Research in Environmental Biology）；植物；啮齿动物</i>.