The Conversion of Abandoned Chestnut Forests to Managed Ones Does Not Affect the Soil Chemical Properties and Improves the Soil Microbial Biomass Activity

Abstract

Recently, several hectares of abandoned chestnut forests (ACF) were recovered into chestnut stands for nut or timber production; however, the effects of such practice on soil mineral horizon properties are unknown. This work aimed to (1) identify the better chestnut forest management to maintain or to improve the soil properties during the ACF recovery, and (2) give an insight into the effect of unmanaged to managed forest conversion on soil properties, taking in consideration sweet chestnut (Castanea sativa Mill.) forest ecosystems. The investigation was conducted in an experimental chestnut (Castanea sativa Mill.) forest located in the northern part of the Apennine chain (Italy). We identified an ACF, a chestnut forest for wood production (WCF), and chestnut forests for nut production with a tree density of 98 and 120 plants ha−1 (NCFL and NCFH, respectively). WCF, NCFL and NCFH stands are the result of the ACF recovery carried out in 2004. After 15 years since the ACF recovery, generally, the effects on the main soil chemical properties were negligible. Some differences occurred for the water-soluble organic carbon (WSOC) and microbial biomass and its activity. NCFL showed the highest WSOC content in the uppermost soil horizon likely due to higher amount of roots which are source of labile organic compounds. The higher WSOC amount might explain the greatest amount of microbial biomass in the A horizon of NCFL. Furthermore, the microbial biomass harboring in the A horizon of NCFL has also shown both a better C use efficiency and a larger soil organic carbon immobilization in the microbial biomass itself. Our data would indicate that the ACF recovery into pure chestnut forests did not have negative impacts on soil chemical and biochemical properties, though chestnut stands for nut production with a low plant density are the most suitable ones.

Soil organic carbon stock assessment in forest ecosystems through pedogenic horizons and fixed depth layers sampling: What's the best one?

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Pedodiversity and Organic Matter Stock of Soils Developed on Sandstone Formations in the Northern Apennines (Italy)

“…This study used a dataset of 147 georeferenced soil profiles (Table S1 of the Supplementary Materials) located in the Northern Apennines in Italy. Such soil profiles are the result of projects financed by public institutions and self-financed projects conducted in the last 15-20 years by the authors of the present manuscript whose results were published in several papers [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67]. Specifically, the soil profiles were located at altitudes ranging from 200 to 2134 m a.s.l.…”

Soil Organic Carbon Stock Assessment for Volunteer Carbon Removal Benefit: Methodological Approach in Chestnut Orchard for Fruit Production

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“…Instead, in CC, the stools are cut roughly every 20-25 years, while the understory is removed yearly and left on the soil's surface. The choice to take into account the CC to CO conversion was based on the growing interest of farmers to restore chestnut stands [70]. Within CO and CC, a target area 1 ha wide was identified, which was theoretically divided into 4 plots 2500 m 2 wide.…”