Roadfill Revegetation in Semiarid Mediterranean Environments. Part II: Topsoiling, Species Selection, and Hydroseeding

Abstract

Erosion is one of the main problems in roadfill restoration. Revegetation is widely used as a method to reduce erosion rates, and it is often carried out through hydroseeding. In semiarid Mediterranean conditions, this approach to revegetation often produces poor results due to climatic limitations. We evaluated whether (1) spreading topsoil and (2) hydroseeding with local rather than commercial species mixtures could improve the vegetative cover of roadfills. The study was carried out in 24 plots over a 20-month period. At the end of the study, vegetation cover was higher in topsoiled plots (38.8%) than in nontopsoiled plots (21.5%). Locally selected species produced higher vegetative cover (61.1%) than did standard commercial species (52.2%). After 20 months, the erosion index was not different among any treatment probably due to the low sensitivity of this variable. These results suggest that amendment of soils through the addition of topsoil is an important technique in roadfill revegetation in Mediterranean environments. Additionally, hydroseeding with local species will produce better vegetative cover on roadfills than does hydroseeding with available commercial species.

A Comparative Approach to Artificial and Natural Green Walls According to Ecological Sustainability

“…Plant communities in natural systems are highly variable until they come to the condition of climax, and they pass through various metamorphosis stages. Therefore, the natural plants also need maintenance activities such as irrigation, fertilization, pruning, protection from harm, dead cover cleaning, and tillage until they reach the climax [38][39][40]. Maintenance activities can also be partially stopped after natural species climax.…”

Does topsoil accelerate the decomposition of litter on roadslopes?

“…This resource provides seeds, organic matter and more microbial activity than the rest of the soils used in infrastructure, which favors the establishment of plant cover (Holmes, 2001;Tormo et al, 2007;Mola et al, 2011). The effects of this treatment on nutrient recycling have never been studied.…”

Utilizing the Analytic Hierarchy Process to Establish Weighted Values for Evaluating the Stability of Slope Revegetation based on Hydroseeding Applications in South Korea

“…Many revegetation applications seek to stabilize barren slopes as a result of urban development and/or road construction. Among the many slope revegetation options available, hydroseeding has been widely applied on large and steep slopes in temperate climates [1][2][3]. Many slope stability analyses conducted by multi-disciplinary experts show that hydroseeding has become the representative application for damaged slopes in South Korea.…”