Carbon balance as affected by biosolid application in reforestations

Abstract

Soils of Mediterranean drylands are characterized by a low fertility and organic matter content because of past land use and disturbances regime. The restoration of these degraded lands faces at the same time problems related to water scarcity and the unpredictability of precipitations with problems with soil physical, chemical, and microbiological properties. Organic amendments may help to improve soil properties and, consequently, enhance planted seedling establishment and performance. In this study, we assessed the C balance of 3 Mediterranean areas planted with Pinus halepensis Mill. seedlings with different treatments of biosolid application. The assessment was conducted at different times after the establishment of treatments and the C dynamics are discussed. We considered 3 biosolid types (air‐dried, fresh sludge, and composted sludge) in application doses ranging from 10 to 320 Mg (d.w.) ha−1. We quantified basal area, pine biomass, biomass of spontaneous vegetation, litter, root density, and soil organic matter. All 3 experimental restoration studies improved restoration success in terms of basal area (ranging from 15% to 300%), especially in composted biosolid at 30 Mg (d.w.) ha−1, whereas litter and, especially, root biomass increased with all biosolid treatments and times since application. Soil organic C was higher in application doses above 30 Mg (dry weight) ha−1 due to the organic matter applied with the sludges. The increment in C sequestration rates associated to these restoration treatments ranged between 0.046 and 0.293 kg C m2 yr−1. These results confirm the suitability of organic amendments as restoration technique in Mediterranean degraded drylands.

Effects of early irrigation and compost addition on soil and vegetation of a restored semiarid limestone quarry are undetectable after 13 years

“…Indeed, organic carbon was not affected by the application of compost or irrigation at the earliest stages of ecological restoration, neither in 2006 nor in 2018. This is in contrast with various studies showing increases in soil carbon content after the application of organic amendments under semiarid environments (Bastida et al, 2008;Luna et al, 2016;Kowaljow et al, 2017), and under Mediterranean climates on similar soils (Clemente et al, 2004;Miralles et al, 2009;Ojeda et al, 2015;Valdecantos and Fuentes, 2018). The lack of response to compost in our site could be related to: i) the smaller amount of compost added (regarding some of the above-cited studies), or ii) to the relatively high fertility of the substrate used on top of the restored slope (a 40 cm-depth layer of topsoil with average soil organic carbon concentration of 1.6%; Soliveres et al 2012), which probably supplied the soil resources demanded by growing herbaceous vegetation.…”

A review of studies on bricks using alternative materials and approaches

“…Las enmiendas del suelo con biosólidos mejoraron el éxito en la restauración de los suelos, especialmente con los biosólidos compostados. (Valdecantos & Fuentes, 2018) Aplicación al suelo El uso de los biosólidos en la aplicación al suelo promueve la acumulación de micro plásticos produciendo efectos perjudiciales sobre los organismos del suelo y aumenta la acumulación de otros micro contaminantes, como los metales pesados, poniendo en riesgo los ecosistemas y la salud humana (Mohajerani & Karabatak, 2020) Fuente: Propia Análisis y propuesta para el uso potencial de biosólidos de PTAR en la fabricación de ladrillos de arcilla…”

Restoration and rehabilitation of degraded land in arid and semiarid environments: Editorial

“…Revegetation efforts generally result in improvement of soil fertility and enhancement of ecosystem services and functions such as carbon sequestration (Gao, Dang, Zhao, Liu, & Liu, 2018), nutrient cycling (Barliza, Peláez, & Campo, 2018;Hu et al, 2018), and soil microbial diversity and activity (Garcia et al, 2018;Liu et al, 2019); nevertheless, it can also lead to adverse effects such as salinity which may affect the success of restoration efforts in the long term (Yu & Wang, 2018) and generally increases plant productivity and carbon sequestration in the medium or long-term, as highlighted by Valdecantos and Fuentes (2018). Also in this issue, Luna, Vignozzi, Miralles, and Solé-Benet (2018) show that woodchip mulch can be effective for trapping runoff and sediment in mine rehabilitation sites, whereas organic amendments formed by composted waste can improve infiltration and reduce water erosion (Figure 2).…”

“…Organic amendments such as biosolids, composted material and mulches may increase soil microbial activity, which favor organic matter decomposition and mineralization, and generally increases plant productivity and carbon sequestration in the medium or long-term, as highlighted in this issue by Valdecantos and Fuentes (2018). Also in this issue, Luna et al (2018), show that woodchip mulch can be effective for trapping runoff and sediment in mine rehabilitation sites whereas organic amendments formed by composted waste can improve infiltration and reduce water erosion (Figure 2).…”

“…The use of amendments in restoration programs is being increasingly encouraged because of their positive effects on soil physical, chemical, and biological characteristics (Hueso-González, Muñoz-Rojas, & Martínez-Murillo, 2018). Organic amendments such as biosolids, composted material, and mulches may increase soil microbial activity, which favor organic matter decomposition and mineralization, and generally increases plant productivity and carbon sequestration in the medium or long-term, as highlighted by Valdecantos and Fuentes (2018). Also in this issue, Luna, Vignozzi, Miralles, and Solé-Benet (2018) show that woodchip mulch can be effective for trapping runoff and sediment in mine rehabilitation sites, whereas organic amendments formed by composted waste can improve infiltration and reduce water erosion (Figure 2).…”