Adaptation to climate change: thinking about new management strategies for Patagonian meadows

ENRIQUEZ A.S., CREMONA M.V., PERI P.L.

Sao Paulo

Congreso; Inter-american Institute for Global Change Research; 2017

Efforts to address climate change problems and to alleviate poverty are increasing globally. In driest areas sustainable land management?s practices are especially needed. In North Patagonia, Argentina, a type of continental wetland (meadows) is developed in low lands were superficial and sub-superficial runoff water concentrates. These ecosystems provide key natural resources and ecosystem services for the development and sustainability of rural environments. In this study we first evaluate the link between soil and plant parameters and water inputs, through observational studies in meadows located in three points of a West-East precipitation gradient (650, 250 and 150 mm yr-1). We also study how the soil organic matter in meadows change with an artificially increasein the mean annual temperature (MAT), through manipulative essays in the field (open top chambers). Results showed that mean annual precipitation (MAP) have influence on aerial and belowground net primary production (from West to East: 722, 674, 220 g m-2 yr-1, and 2107, 5915, 2709 g m-2 yr-1, respectively) and in the soil organic carbon and nitrogen (from West to East: 89, 160 and 30 g kg-1, and 0.6 %, 0.9 %, and 0.2 %, respectively); however data shows that the local hydrology (runoff input with effect in the hydroperiod) can have strongest influence than the MAP. The increase in MAT generated a strong modification in the particulate organic matter structure in just one year. As the scenariosfor 2090 in this region predict an increase in the MAT and a modification in water regimes, and as the present land use is damaging soil structure in Patagonian meadows (e.g. an overall reduction of 35 % in the total ecosystem carbon pool and of 43% in total nitrogen), our results reflect the need of exploring new management?s strategies to reach sustainable use in the coming years.