How far surface water fluxes determine restoration success in Mediterranean degraded areas? Implications for dryland precision restoration

Abstract

Drylands functioning depends on water fluxes and the retention of resources. The restoration of degraded areas should mimic the natural arrangement of vegetation in the landscape in a source-sink pattern.Reintroducing key woody seedlings through planting is a major concern in ecological restoration as these areas use to be overpassed degradation thresholds and ecosystem functions are limited. However, it is not clear how natural fluxes might determine seedlings performance of key shrub species. We have analyzed the microcatchment surface area of planting spots with and without water optimization treatment (waterproof surfaces with dry wells) and the survival and growth of Olea europaea seedlings during six years after planting in a semiarid degraded landscape. We recorded a positive effect of water optimization treatment in seedling survival and growth highlighting water limitation of these sites. We did not observe a clear and linear relationship between microcatchment collecting surface area and plant performance. The higher the collecting surface the lower the retention capacity of the planting pitch suggesting a loss of the integrity of the planting hole structure. Water optimization treatments were especially effective when collecting surface areas were low. These results might be useful for designing precision restoration actions in degraded landscapes.

Innovative Techniques for Landscape Recovery after Clay Mining under Mediterranean Conditions

“…(5) Low-cost actions with many associated benefits: it has been widely reported that resources management may improve ecosystem functioning and the provision of services, while minimizing costs [30,77]. The use of innovative low-cost techniques appears to be a good option to optimize resource availability rather than other more expensive options like irrigation systems [78]. Microcatchments have been previously tested with positive (4) Accurate species selection, seed provenance and suitable plant nursery techniques: determining proper ecosystem references allows detailed species selection to be carried that suits the specific physiographic characteristics of the restoring area.…”

The role of ecohydrological (dis)connectivity in dryland functioning and management

“…Usando un modelo espacialmente explícito, Berghuis et al (2020) encontraron también una relación unimodal entre el tamaño de sumideros artificiales distribuidos de forma regular sobre una ladera de suelo desnudo y la biomasa vegetal promovida por esta acción. El crecimiento y el estado general de las plantas en una mancha de vegetación dependen positivamente del tamaño de su área fuente (Urgeghe y Bautista 2015), pero esta relación tiende a un valor máximo cuando se satura la capacidad sumidero de la mancha (Smanis et al 2021), abundando en la idea de una proporción óptima de fuentes y sumideros (Puigdefábregas et al 1999). Algunos trabajos con modelos muestran, sin embargo, que coberturas iniciales de sumideros muy bajas puede ser suficiente para desencadenar el restablecimiento de una cubierta vegetal discontinua en el ecosistema (Mayor et al 2019;Berghuis et al 2020).…”

Assessing reforestation failure at the project scale: The margin for technical improvement under harsh conditions. A case study in a Mediterranean Dryland

“…Several management decisions can increase mortality in dryland plantations regardless of meteorology, such as shallow site preparation (Palacios et al, 2009, Löf et al, 2012Smanis et al, 2021), unsuitable planting timing (McTague and Tinus, 1996;Pardos et al, 2003), pre-planting mishandling of plant stock (Edgren, 1984), careless execution of planting (Mullin, 1974;Long, 1991) or inadequate species selection (Suárez et al, 2011;Meli et al, 2014;del Campo et al, 2020).…”