Plant Density at Permanent Quad Locations on the Jornada Experimental Range, 1915-ongoing

This ongoing data set contains counts of perennial forbs and subshrubs in 122 1m x 1m quadrats on the Jornada Experimental Range in the northern extent of the Chihuahuan Desert of New Mexico, USA. These quadrats were established to investigate livestock grazing effects on plant community dynamics as well as responses to variable climatic conditions over time. Vegetation monitoring is carried out by charting the locations of forbs and subshrubs within each quadrat. Quadrats were established at different times, with start dates from 1915 to 1935. Specific quadrat locations were selected for a variety of reasons, but the overall intent was to represent varying plant community conditions across the Jornada Experimental Range. From 1915 to 1924 charting was done by dividing the quadrat frame into a decimeter grid using straps and reproducing locations of plants on grid paper. From 1925 to 2016 charting was done using a pantograph. With few exceptions, quadrats were charted until 1947, and a portion of the quadrats were charted intermittently between 1947 and 1979. Sampling resumed again in 1995 and continues every 5-6 years. Charts are digitally scanned, georeferenced, and chart features are digitally reproduced by hand. This data set is not yet complete; charts are actively being processed by Jornada Experimental Range staff and will be updated to this data package as they become available. A companion data package of basal cover of perennial grasses and canopy cover of shrubs is also available for this project (data package knb-lter-jrn.210351001).   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=210351002 Webpage with information and links to data files for download

本持续更新的数据集收录了美国新墨西哥州奇瓦瓦沙漠北部地区，乔尔纳达实验站内122个1米×1米的样方中多年生草本植物和亚灌木的数量。这些样方旨在研究放牧对植物群落动态的影响以及植物对气候变化响应的变化。植被监测通过绘制每个样方内草本植物和亚灌木的位置来完成。样方建立于不同的时期，起始时间从1915年至1935年。具体样方位置的选择基于多种原因，但其总体目标是代表乔尔纳达实验站内不同的植物群落状况。从1915年至1924年，通过将样方框架划分为分米网格，并使用皮带在网格纸上复现植物位置来进行绘图。从1925年至2016年，则采用绘图仪进行绘图。除少数例外，样方绘图一直持续至1947年，部分样方在1947年至1979年间间歇性绘图。1995年重新开始采样，并每隔5至6年进行一次。图表已进行数字化扫描、地理编码，并由人工手动复现图表特征。该数据集尚未完整；乔尔纳达实验站的工作人员正在积极处理图表，并将随着可用性更新至该数据包。此外，本项目还提供了多年生草本植物基盖度和灌木冠层盖度的伴随数据包（数据包编号 knb-lter-jrn.210351001）。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=210351002，包含信息及数据文件下载链接。