The dynamics of carbon accumulation in Eucalyptus and Acacia plantations in the Pearl River delta region

Abstract

& Key message Plantation type and age strongly influence the quantity of carbon stored in forest ecosystems. The marked increase in total ecosystem carbon stock achieved over time by the Eucalyptus and Acacia plantations has confirmed that the afforestation of degraded soils can contribute positively to carbon sequestration. & Context Reforestation has been widely conducted to restore and protect the eroded red soil in south China in recent decades. The question as to whether the content of soil organic carbon (SOC) can be boosted by establishing plantations of fast-growing tree species remains unresolved. & Aims We addressed whether the afforestation of degraded soils can contribute positively to carbon sequestration, and whether the accumulation of SOC is more effective under a nitrogen fixing species such as Acacia than under Eucalyptus. & Methods Here, a study was undertaken to measure the quantity of total ecosystem carbon (TEC) accumulated by plantations of both Eucalyptus and Acacia spp. in the Pearl River Delta region of southern China. & Results The quantity of TEC increased significantly with stand age in both plantation types (P < 0.05). The largest single component of TEC was SOC, with stand age having a considerable effect on both SOC and overall biomass. The accumulation of SOC in the top 100 cm of the soil profile was higher under Acacia than under Eucalyptus (P < 0.05). & Conclusion In terms of carbon sequestration, the afforestation of Eucalyptus and Acacia represent an effective forest management practice. The accumulation of SOC is more effective under Acacia than under Eucalyptus.Keywords Total ecosystem carbon . Forest type . Stand age . Biomass . Soil organic carbon Contribution of the co-authors Hui Zhang: data collection, analyzed the data, and writing the manuscript. HuaBo Duan: analyze the experimental data and revise the manuscript. MingWei Song: designed experiment program (including all experimental data), further help the first author with the laboratory experiment, and cowrote the manuscript. DongSheng Guan: experimental design, coordinating the research project, and supervised the field measurement.

Soil Properties and Biomass Attributes in a Former Gravel Mine Area after Two Decades of Forest Restoration

“…Our results add to these studies by demonstrating that successful soil restoration could be obtained within two decades, at least in some tropical environments [56]. These results suggest that there is no universal global period for soil restoration, with significant differences depending on the specific context of each ecosystem, such as climatic conditions, surrounding vegetation, the origin of the disturbance, and the restoration approach [22,56,57,67]. Focusing on soil restoration, our results enable us to support afforestation after soil amendments as a critical catalyst for restoring soil properties after mining.…”

Enhancement of Soil Organic Carbon by Acacia Mangium Afforestation in Southeastern Region, Vietnam

“…In the three age-sequence A. mangium stands of this study, the SOC concentration was the highest in the surface 0-10 cm soil layer and revealed a decreasing trend with increasing depth (Figure 2a). The SOC produced from the decomposition of root system and litter near the ground surface will get into the topsoil first, this could be responsible for the significant higher SOC content in the upper soil layer (Zhong and Qiguo, 2001;He et al, 2009;Laik et al, 2009;Thanh and Cuong, 2017a;Zhang et al, 2018). The concentration of C stored in the top three soil layers (0-10 cm, 10-20 cm, and 20-30 cm) and the deepest layer (30-50 cm) significantly increased with increased age of A. mangium plantations, probably due to the increase of litter productivity and slow decomposition in older stands (Herdiyanti and Sulistyawati, 2009;Ming et al, 2014).…”

“…Whereas others showed an increasing SOC in the early period after afforestation followed by a gradual decrease (Ali et al, 2019;Zhang et al, 2019), a stable SOC after afforestation (Simon et al, 2012), or no significant increase with stand development (Matthias and Arain, 2006;Yue et al, 2018). Nonetheless, according to most researches, SOC significantly increased with forest age (Cheng et al, 2015;Zhang et al, 2018). One possible interpretation to this discrepancy is that, in addition to stand age, several other factors impact SOC accumulation, such as tree species, forest types, climate conditions, soil physicochemical characteristics, and former land use (Smal and Olszewska, 2008;Noh et al, 2010).…”

“…Thus, minor changes in the C reservoir of forest soil will dramatically influence the global C balance, which impacts global climate change (Albaladejo et al, 2013). The SOC is principally determined by the balance between C inputs through litterfall and root turnover and loss of C primarily through organic matter decomposition, which processes are controlled by various environmental variables, including vegetation biomass (Wang et al, 2013;Zhang et al, 2018) and soil physicochemical properties such as soil N (Batjes, 1996;Cong et al, 2016), soil texture (Jobbágy and Jackson, 2000;Liu et al, 2016), soil P (Zu et al, 2011;, soil K (Zu et al, 2011;Zhang et al, 2016), soil pH (Robson and Foy, 1990;Thomas, 1996;Chen et al, 2004), and soil BD (Hobley et al, 2015;Ngaba et al, 2020). Hence, understanding the SOC storage dynamics and the factors that control this process in forest ecosystems is critical for better C budget management and climate change mitigation options.…”

Peer Review #1 of "Effects of vegetation restoration on soil quality in fragile karst ecosystems of southwest China (v0.1)"

“…Similarly, Zhang et al (2019a) found that restoration type and soil depth were the two most important factors contributing to SQI of vegetation restoration in degraded karst areas. In addition, restoration time played a non-negligible role in VSQI, due mainly to ecosystem carbon stock sequestration achieved over time as a result of vegetation restoration (Zhang et al 2018a), since soil organic matter/carbon is the key factor to determining soil quality (Bunemann et al 2018). In conclusion, vegetation restoration type is the dominant factor that affects soil quality and the longer restoration time achieves the better restoration effects.…”