Soil organic carbon storage changes in coastal wetlands of the modern Yellow River Delta from 2000 to 2009

J. Yu,Y. Gao,D. Zhou,H. Dong,G. Han,Y. Wang,G. Wang,H. Wu,P. Mao,Y. Li

doi:10.5194/bg-9-2325-2012

Abstract

Abstract. Soil carbon sequestration plays an essential role in mitigating atmospheric CO2 increases and the subsequently global greenhouse effect. The storages and dynamics of soil organic carbon (SOC) of 0–30 cm soil depth in different landscape types including beaches, reservoir and pond, reed wetland, forest wetland, bush wetland, farmland, building land, bare land (severe saline land) and salt field in the modern Yellow River Delta (YRD) were studied based on the data of the regional survey and laboratory analysis. The landscape types were classified by the interpretation of remote sensing images of 2000 and 2009, which were calibrated by field survey results. The results revealed an increase of 10.59 km2 in the modem YRD area from 2000 to 2009. The SOC density varied ranging from 0.73 kg m−2 to 4.25 kg m−2 at depth of 0–30 cm. There were approx. 3.559 × 106 t and 3.545 × 106 t SOC stored in the YRD in 2000 and 2009, respectively. The SOC storages changed greatly in beaches, bush wetland, farm land and salt field which were affected dominantly by anthropogenic activities. The area of the YRD increased greatly within 10 years, however, the small increase of SOC storage in the region was observed due to landscape changes, indicating that the modern YRD was a potential carbon sink and anthropogenic activity was a key factor for SOC change.

Highlights

One of the most dramatic changes in the global system resulting from human activity is the rising greenhouse gases (Ogle et al, 2003; Vitousek et al, 1997)
Soil organic carbon (SOC) stock is the largest pool in the terrestrial ecosystem, with a storage of approx. 1500 Pg in the top 100 cm depth layer, only a small change in storage has an impact on the level of atmospheric gaseous carbon (Desjardins et al, 2007; Feller and Bernoux, 2008; IPCC, 2001; Janzen, 2004; Xu et al, 2011)
The landscapes in the modern Yellow River Delta (YRD) were divided to nine types, i.e. beaches, reservoir and pond, reed wetland, forest wetland, bush wetland, farmland, building land, bare land and salt field (Fig. 2a, b) based on the interpretation results of remote sensing images by our classification system established

Summary

Introduction

One of the most dramatic changes in the global system resulting from human activity is the rising greenhouse gases (Ogle et al, 2003; Vitousek et al, 1997). The increase in carboncontaining greenhouse gases is presumed to be the basis of current and future climate change (Hansen et al, 2000; Levitus et al, 2001; Schimel et al, 2000; Su et al, 2006). Soil organic carbon (SOC) stock is the largest pool in the terrestrial ecosystem, with a storage of approx. Soil carbon sequestration is believed to be one of the cost-effective ways to mitigate CO2 increase and the global greenhouse effect (Janzen, 2004; Xu et al, 2011). About 20 % ∼ 25 % of Published by Copernicus Publications on behalf of the European Geosciences Union

Methods

Results

Conclusion