Spatial and temporal variation of primary production of Patagonian wet meadows

BUONO, G.; OESTERHELD, M.; NAKAMATSU, V.; PARUELO, J.M.

JOURNAL OF ARID ENVIRONMENTS

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Año: 2010 vol. 74 p. 1257 - 1261

0140-1963

In extra-Andean Patagonia, wet meadows contrast with the prevailing arid steppes, and presenta gradient of water availability from the periphery to the center. The objectives of this paper are todescribe the spatial and temporal variation of aerial net primary production (ANPP) of Patagonianmeadows, and to obtain a model for the relationship between the normalized difference vegetationindex (NDVI) and ANPP. We determined ANPP in four regionally scattered meadows during 3e5 yearsand in three positions of the gradient of water availability. In one meadow, we correlated ANPP withNDVI during 2 years. Annual ANPP was 2e3 times larger in the center than in the periphery, and alsovaried 2e3 fold among the four meadows. The interannual variation of ANPP was high and similar acrossmeadows and zones. ANPP was closely correlated with NDVI through a linear model.Within the growingseason, the central zone had a more extended period of high NDVI into the summer than the peripheraland the intermediate zones.We conclude that (1) the local variation of ANPP across the gradient of wateravailability is strong and must be taken into account for management, and (2) the highly variable ANPPmay be monitored by remote sensing.