Rehabilitation of degraded areas in northeastern Patagonia, Argentina: Effects of environmental conditions and plant functional traits on performance of native woody species

Abstract

Degradation processes affect vast area of arid and semiarid lands around the world and cause damages in environment and health people. Degradation processes are impulsed for human produtive activities that cause direct and indirect effects on natural resources as species extintion to regional or predial scale, reduction and elimination of vegetation cover, soil erosion, among others. In front of this, ecological rehabilitation is an important tool to recover key aspects from degraded ecosystem. To develop rehabilitation trials is desirable use native plant species of local procedence with characteristics that allow them high survival and growth rates. The aim of this work was to assess the survival and growth of native woody species in degraded areas of the northeast of Patagonia and relate them to plant functional traits and environmental variables. We observed high early and late survival rates and growth by Prosopis flexuosa and Schinus johnstonii, and low values by Condalia microphylla and Geoffroea decorticans. Early survival rates are positevely associated with Specific Leaf Area (SLA) and precipitation, and negatively associated with wood density and maximum mean temperature of January and minimum mean temperature of July. Late survival rates were positevely associated with SLA and soil organic matter, and negatively associated with plant height and precipitations. Temperatures had a positive effect on late survival rates once plants overcame the critical threshold of the first summer after they were transplanted to the field. Prosopis flexuosa and S. johnstonii were the most successful species of our study. This could bedue to their functional traits that allow this species to acclimatize to local environments charecteristics. It is desirable to continue the researchs about C. microphylla and G. decorticans to know aspects related to productive conditions, rustification processes, autoecology and potential usefull in ecological rehabilitation trials.