Carbon storage in China\u2019s terrestrial ecosystems: A synthesis

Li Xu,Jianping Ge,Ding Wen,Guirui Yu,Shuli Niu,Shenggong Li,Nianpeng He,Yang Gao,Qiufeng Wang

doi:10.1038/s41598-018-20764-9

Abstract

It is important to accurately estimate terrestrial ecosystem carbon (C) storage. However, the spatial patterns of C storage and the driving factors remain unclear, owing to lack of data. Here, we collected data from literature published between 2004 and 2014 on C storage in China’s terrestrial ecosystems, to explore variation in C storage across different ecosystems and evaluate factors that influence them. We estimated that total C storage was 99.15 ± 8.71 PgC, with 14.60 ± 3.24 PgC in vegetation C (Veg-C) and 84.55 ± 8.09 PgC in soil organic C (SOC) storage. Furthermore, C storage in forest, grassland, wetland, shrub, and cropland ecosystems (excluding vegetation) was 34.08 ± 5.43, 25.69 ± 4.71, 3.62 ± 0.80, 7.42 ± 1.92, and 15.17 ± 2.20 PgC, respectively. In addition to soil nutrients and texture, climate was the main factor regulating the spatial patterns of C storage. Climate influenced the spatial patterns of Veg-C and SOC density via different approaches, Veg-C was mainly positively influenced by mean annual precipitation (MAP), whereas SOC was negatively dependent on mean annual temperature (MAT). This systematic estimate of C storage in China provides new insights about how climate constrains C sequestration, demonstrating the contrasting effects of MAP and MAT on Veg-C and SOC; thus, these parameters should be incorporated into future land management and C sequestration strategies.

Highlights

Terrestrial ecosystems are the main component of carbon (C) pools in the Earth’s system, and contribute considerably to the global C balance[1,2,3]
The main objectives of this study were to: (1) generate a comprehensive C density dataset from which to estimate C storage in China’s terrestrial ecosystems; (2) explore the spatial patterns of vegetation C (Veg-C) and soil organic C (SOC) density and the main factors influencing these patterns; and (3) test the assumption that climate influences the patterns of Veg-C and SOC density through different approaches (MAT vs. Mean annul precipitation (MAP))
Veg-C and SOC (0–100 cm soil layer) storage were estimated as 14.60 ± 3.24 and 84.55 ± 8.09 Pg C, respectively, with a sum of 99.15 ± 8.71 Pg C storage in China’s terrestrial ecosystems (Fig. 1; Supplementary Table S1)

Summary

Introduction

Terrestrial ecosystems are the main component of carbon (C) pools in the Earth’s system, and contribute considerably to the global C balance[1,2,3]. Uncertainty remains high among the various studies, especially with respect to estimating SOC storage in China’s terrestrial ecosystems, with values ranging from 50.0 to 185.7 Pg C (Table 1). This large uncertainty is mainly attributed to variation in the collection periods, data validity, and estimation methods[19]. Few studies have used field investigation data to estimate C storage in China’s terrestrial ecosystems, because a synthetic field investigation of C storage in vegetation and soil at a national scale is time-consuming, laborious, and difficult to implement, especially in remote areas[44]. Several factors, such as site conditions (climate), vegetation type, soil properties (clay content, soil moisture, pH, nutrient status), and land use, could influence the spatial www.nature.com/scientificreports/

Objectives

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Results

Conclusion