Nutrient losses in runoff from grassland and shrubland habitats in Southern New Mexico: I. rainfall simulation experiments

TitleNutrient losses in runoff from grassland and shrubland habitats in Southern New Mexico: I. rainfall simulation experiments
Publication TypeJournal Article
Year of Publication1999
AuthorsSchlesinger WH, Abrahams AD, Parsons AJ, Wainwright J
JournalBiogeochemistry
Volume45
Pagination21-34
Date Published1999
Accession NumberJRN00282
Call Number00715
Keywordsarticle, articles, desertification, grassland, hydrology, grassland, hydrology, nutrient export, hydrology, rainfall simulation, hydrology, shrubland, hydrology, surface runoff, journal, journals, nitrogen, nutrient budgets, phosphorus, runoff
Abstract

Rainfall simulation experiments were performed in areas of semiarid grassland (Bouteloua eriopoda) and arid shrubland (Larrea tridentata) in the Chihuahuan desert of New Mexico. The objective was to compare the runoff of nitrogen (N) and phosphorus (P) from these habitats to assess whether losses of soil nutrients are associated with the invasion of grasslands by shrubs. Runoff losses from grass- and shrub-dominated plots were similar, and much less than from bare plots located in the shrubland. Weighted average concentrations of total dissolved N compounds in runoff were greatest in the grassland (1.72 mg/l) and lowest in bare plots in the shrubland (0.55 mg/l). More than half of the N transported in runoff was carried in dissolved organic compounds. In grassland and shrub plots, the total N loss was carried in dissolved organic compounds. In grassland and shrub plots, the total N loss was highly correlated to the total volume of discharge. We estimate that the total annual loss of N in runoff is 0.25 kg/ha/yr in grasslands and 0.43 kg/ha/yr in shrublands -- consistent with the depletion of soil N during desertification of these habitats. Losses of P from both habitats were very small.

URLfiles/bibliography/JRN00282.pdf
DOI10.1023/A:1006020831706
Reprint EditionIn File