Field collection
Precipitation is collected monthly at each location in a National
Weather Service type standard rain gauge with an 8-inch diameter
catchment orifice. A small amount of mineral oil is used to
prevent evaporation during the month. As close to the end of the
month as possible, USDA-ARS personnel travel to each standard
gauge and measure the collected rainfall with a graduated
cylinder. To measure the effects of nitrogen fertilizer on plant
communities, the average percent coverage of each plant species
was calculated along plant intercept lines perpendicular to the
permanent, 2.7 km transects. There are 91 station markers arranged
at 30 meter intervals along each permanent transect, and each has
a plant intercept line that extends 15 meters on either side of
the transect. These data are available in dataset
knb-lter-jrn.210119001.
Data processing
These measurements are entered directly into a spreadsheet and
emailed to the Jornada Experimental Range network. Actual
collection dates before 2010 are not available.