Forest management and carbon sequestration in the Mediterranean region: A review

Abstract

Aim of study: TTo review and acknowledge the value of carbon sequestration by forest management in the Mediterranean area. Material and methods:We review the main effects of forest management by comparing the effects of silvicultural systems (even-aged vs. uneven-aged stands, coppice systems, agroforestry systems), silvicultural options (thinning, rotation period, species composition), afforestation, harvesting, fire impact or effects of shrub layer on carbon sequestration in the Mediterranean area.Main results: We illustrate as forest management can clearly improve forest carbon sequestration amounts. We conclude that forest management is an effective way to maintain and enhance high carbon sequestration rates in order to cope with climate change and provision of ecosystem services. We also think that although much effort has been put into this topic research, there are still certain gaps that must be dealt with to increase our scientific knowledge and in turn transfer this knowledge to forest practitioners in order to achieve sustainable management aimed at mitigating climate change.Research highlights: It is important to underline the importance of forests in the carbon cycle as this role can be enhanced by forest managers through sustainable forest management. The effects of different management options or disturbances can be critical as regards mitigating climate change. Understanding the effects of forest management is even more important in the Mediterranean area, given that the current high climatic variability together with historical human exploitation and disturbance events make this area more vulnerable to the effects of climate change.Additional keywords: global carbon cycle; forest sink; forest mitigation strategies; carbon sequestration potential; climate change mitigation; Mediterranean forests.

Airborne Laser Scanning Cartography of On-Site Carbon Stocks as a Basis for the Silviculture of Pinus Halepensis Plantations

“…These results are contrary to those found in some previous studies, where thinning operations had a non-significant or negative impact on soil C in Mediterranean pine forests [27,29,74] but not to those of other studies [10,66]. Thinning may improve C sequestration through several factors involved in SOC accumulation: variation in the quality and quantity of inputs (litterfall and logging residues), an increase in N use efficiency, protection of both new and old SOC in mineral-associated fractions (<50 µm) and a greater micro-climatic effect on litter decomposition [13,75,76], enhancing long-term storage in the soil [77].…”

“…In line with our first hypothesis, the biomass C stock was significantly higher in control (unthinned) plots-which is consistent with estimates for other Aleppo pine stands in the region that support relatively low basal areas [64,65]; and for other pine species [27,66,67]. Thinning operations involve a loss of total biomass (without including also the biomass that is removed), which results in lower densities and basal areas in thinned stands [27]. In this study, the average biomass C stock calculated for P. halepensis forests ranged between 41.65 Mg ha −1 (unthinned plots) and 13.93 Mg ha −1 (heavy thinning).…”

“…Although one to two silvicultural thinning interventions are typically applied during a rotation of P. halepensis stands [21], in many cases few or none have been applied [22]. However, forest managers strongly recommend the use of silvicultural treatments to manipulate stand densities and tree growth, in order to maintain and increase C stocks [22,23] and to encourage sustainable forest management, thereby mitigating climate change effects on Aleppo pine forests (e.g., [24][25][26][27])…”

Impacts of Global Change on Mediterranean Forests and Their Services

“…The most important cultural and social functions are the recreational, educational and leisure uses, opportunities for research, their traditional cultural and emotional values and the esthetics of pleasant landscapes, which give rise to important economic activities such as tourism and hiking [217]. Among these features and ecosystem services, the water resources and the storage of C are especially important for their implications in all these services, because they are the basis of the primary production that supports the services and because of the effects they have on climate change [218]. All previously discussed, global changes will clearly have an impact on many of these goods and services and will therefore affect socioeconomic systems [6].…”

Estimation of carbon storage of forest biomass for voluntary carbon markets: preliminary results

“…Often, in mountainous ecosystems, forest area is very high and it is not possible to enhance further the carbon storage by afforestation or reforestation activities. In this case, the carbon storage can be enhanced only through IFM systems, that include different practices, mainly referred to: (1) extension of the rotation length, (2) reduction of woody biomass harvesting compared to the maximum volume allowed by forest management plans (FMPs), (3) conversion of aged and/or abandoned coppices to high forests, (4) increase of carbon retention in HWPs, (5) increase of the use of HWPs instead of more fossil-energy intensive materials, and (6) increase of the use of woody biofuels to substitute fossil fuels (Aruga et al 2013;Alberdi et al 2016;Ruiz-Peinado et al 2017;Vacchiano et al 2018). Each CC exchanged on a VCM promotes the mitigation of 1 t of CO 2 released into the atmosphere from anthropogenic activities.…”