Revegetation on Tropical Steep Slopes after Mining and Infrastructure Projects: Challenges and Solutions

Abstract

The revegetation of steep slopes after mining and infrastructure projects is not an easy task. To enhance the effectiveness of revegetation projects, the present study aimed to review (i) specific challenges of steep slope revegetation, (ii) ecological succession patterns in similar environments, (iii) soil conditioning and revegetation strategies to enhance vegetation cover, (iv) the importance of microorganisms to enhance steep slope revegetation, and (v) the functional plant traits necessary to establish on steep slopes. In general, steep slopes are characterized by high bulk densities, potentially toxic elements, and low water and nutrient availability. Additionally, high temperature and elevated radiation constrain the soil conditioning and vegetation cover establishment. Lessons from ecological succession in natural steep slope habitats show that steep slope revegetation is a long-term process. Planting strategies, including hydroseeding and geotextiles, may enhance the implementation of vegetation cover. Different plant functional groups show adaptations necessary for establishment in steep slope environments, and mixtures of species containing different functional groups can promote diverse and resilient plant communities. Promising species may be retrieved from local rupestrian ecosystems, as these floras are adapted to shallow, oligotrophic soils. Further research on combining methods of soil conditioning with individual planting and/or seeding strategies of carefully selected species is necessary to enhance steep slope revegetation and rehabilitation, contributing to slope stability, erosion reduction, and carbon fixation in the long term.

Evaluating Soil Loss in a Kimchi Cabbage Cropping System in the Highlands of Gangwon, Korea

“…This suggests that KC was more efficient in reducing soil losses on steeper slopes. Steeper slopes have higher soil loss potential due to accelerated runoff velocities (Siswanto and Sule, 2019;Gastauer et al, 2022), and as such, introduction of a soil cover in such slopes presents more benefits to the system, compared to gentle slopes where soil losses are not as much. The higher average soil organic matter content in the 15% slope lysimeters (Table 1) compared to 2 and 7% slopes may have also contributed to the lower C factors in the 15% slope as higher soil organic matter has been linked with improvement in soil binding properties and soil structure which may lead to reduction in erosion and soil loss compared to bare land (Booth et al, 2005;FAO, 2005).…”

Fertilization during mineland rehabilitation may shift competitive outcomes toward invasive species

“…fertilizers, organic matter, and mulch). Species mixtures currently applied contain commercial fast‐growing legumes and grasses, which are able to achieve rapid vegetation cover that trigger the rehabilitation process (Cristina & Gomes 2013; Silva et al 2018; Gastauer et al 2022). To increase the environmental performance of rehabilitating areas, additional native species have been explored for this purpose (Gastauer et al 2020).…”

“…Here, the inertial overburden not used during the extraction process is deposited, which results in the formation of large waste piles. The environmental rehabilitation of mine pits and waste piles aims to reduce the environmental impact, guarantee slope stabilization and protect soil against erosion (Gastauer et al 2022;Castro et al 2023). For that purpose, slopes are hydroseeded using a mixture of soil amendments (i.e.…”

Ten principles for restoring campo rupestre, a threatened tropical, megadiverse, nutrient‐impoverished montane grassland

“…Hence, understanding water‐ and nutrient‐acquisition (Oliveira et al 2016; Rios et al 2023) strategies should inform species selection aiming at promoting species coexistence and niche segregation. For example, mixtures of species containing different functional groups can promote diverse and resilient plant communities (Gastauer et al 2022). Trait‐based species selection can be implemented using functional trait coordination among plant organs to make more reliable inferences on species strategies and ecosystem functioning (Caminha‐Paiva et al 2021).…”