Carbon Sequestration Special Issue: Journal of Environmental Management
A significant contribution to the carbon sequestration literature will be made when, in Spring 2006, a special issue of the Journal of Environmental Management will be devoted to research produced by the project.

S. Wang, M. Huang, X. Shao, R. Mickler, K. Li, & J. Li. Vertical Distribution of Soil Organic Carbon in China. Environmental Management Vol. 33, Supplement 1, pp. S200–S209. [download the complete publication]

Abstract: Understanding the vertical distributions of soil organic carbon (SOC) is key to predicting and simulating the influences of climate, global change, and human activities on the terrestrial carbon cycle. SOC was measured at soil depths of 0–10, 0–20, 0–30, 0–50, and 0–100 cm in 2473 soil profiles during China’s second national soil survey that was conducted from 1979 to 1992. SOC was spatially extrapolated for China. Mean SOC densities in the top 1 m ranged from 4.65 kg/m2 for bare ground to 17.32 kg/m2 in grassland land cover. SOC in the top 1 m of soil was estimated at 82.5 _ 19.5 Pg C. The total SOC pool held in the top 10, 20, 30, 50, and 100 cm are 22%, 41%, 54%, 74%, and 100%, respectively. One of the objectives of the study is to examine the association of SOC content with climate and to estimate SOC storage in land-cover types at different soil depths. A partial correlation analysis shows that the mean annual precipitation was positively correlated with SOC content and the mean annual temperature was negatively correlated with SOC content, across all depths. The vertical distribution of SOC had a slightly stronger association with temperature than with precipitation in China.

R.Sun, J.M. Chen, Q. Zhu, Y. Zhou, J. Liu, J. Li, S. Liu, G. Yan, & S. Tang. Spatial distribution of net primary productivity and evapotranspiration in Changbaishan Natural Reserve, China, using Landsat ETM+ data. Can. J. Remote Sensing, Vol. 30, No. 5, pp. 731–742, 2004. [download the complete publication]

Abstract: Remote sensing has been a useful tool to monitor net primary productivity (NPP) and evapotranspiration (ET). In this paper, based on field measurements and Landsat enhanced thematic mapper plus (ETM+) data, NPP and ET are estimated in 2001 in the Changbaishan Natural Reserve, China. Maps of land cover, leaf area index, and biomass of this forested region are first derived from ETM+ data. With these maps and additional soil texture and daily meteorological data, NPP and ET maps are produced for 2001 using the boreal ecosystem productivity simulator (BEPS). The results show that the estimated and observed NPP values for forest agree fairly well, with a mean relative error of 8.6%. The NPP of mixed forests is the highest, with a mean of 500 g C m–2·a–1, and that of alpine tundra and shrub is the lowest, with a mean of 136 g C m–2·a–1. Unlike the spatial pattern of NPP, the annual ET changes distinctly with altitude from greater than 600 mm at the foot of the mountain to about 200 mm at the top of the mountain. ET is highest for broadleaf forests and lowest for urban and built-up areas.

S. Wang, H. Tian, J. Liu & S.Pan. Pattern and change of soil organic carbon storage in China: 1960s–1980s. Tellus (2003). [download the complete publication]

Abstract: Soils, an important component of the global carbon cycle, can be either net sources or net sinks of atmospheric carbon dioxide (CO2). In this study, we use the first and second national soil surveys of China to investigate patterns and changes in soil organic carbon storage (SOC) during the period from the 1960s to the 1980s. Our results show that there is a large amount of variability in SOC density among different soil types and land uses in the 1980s. The SOC density in the wetlands of Southwest China was the highest (45 kg m-2), followed by meadow soils in the South (26 kg m-2), forest and woodlands in the Northwest (19 kgm-2), steppe and grassland in the Northwest (15 kgm-2), shrubs in the Northwest (12 kg m-2), paddy lands in the Northwest (13 kg m-2), and drylands in the Northwest (11 kg m-1). The desert soils of theWestern region ranked the lowest (1 kg m-2). The density of SOC was generally higher in the west than other regions. Eastern China had the lowest SOC density, which was associated with a long history of extensive land use in the region. The estimation of SOC storage for the entire nation was 93 Pg C in the 1960s and 92 Pg C in the 1980s. SOC storage decreased about 1 Pg C during the 1960s–1980s. This amount of decrease in SOC for the entire nation is small and statistically insignificant. To adequately characterize spatial variations in SOC, larger sampling sizes of soil profiles will be required in the future analyses.

R. Sun, Y. Zhou, Q. Zhu, J. M. Chen, J. Liu, J. Li, S. Liu, G. Yan, S. Tang. Estimation of net primary productivity and evapotranspiration in Changbaishan, China using ETM data. Canadian Journal of Remote Sensing (submitted December 2003).

Abstract: Remote sensing technology enables us to observe the land surface of large areas frequently. It provides an attractive way to understand the status and dynamics of land surface processes. Therefore, remote sensing has been a useful tool to monitor the net primary productivity (NPP) and evapotraspiration (ET). In this paper, based on the field measurements and Landsat ETM+ data, NPP and ET in the year 2001 in the Changbaishan Nature Reserve, China, are estimated. Maps of land cover type, Leaf area index and biomass of this forest region are first derived from ETM+ data. With these maps and additional data for the soil texture and daily meteorological data, NPP and ET maps in 2001 are produced using the Boreal Ecosystem Productivity Simulator (BEPS). The results show that the estimated and observed NPP values of forest agree fairly well, with the mean absolute error of 10.9%. The NPP of mixed forests is highest with a mean of 532 gCm-2a-1, while the NPP of alpine tundra and shrub is lowest, with a mean of 137 gCm-2a-1. Different from the spatial pattern of NPP, the annual ET distinctly changes with altitude from above 600 mm at the foot of mountain to about 200 mm at hilltop. ET is highest for broadleaf deciduous forests and lowest for urban and built-up areas.

K. Wang, X. Shi, D.Yu, Y. Liang, J. M. Chen and D. Shi. Soil Erosion Dynamic based on Landscape Pattern and Transition Matrices ---A case study of Xingguo County, Jiangxi Provincengguo c, China. Computer and GIS Science (submitted September 2003).

Abstract: Based on soil erosion maps in 1958, 1975, 1982 and 1996, a GIS was used to produce soil erosion raster maps. Changes in soil erosion matrices were calculated by using the landscape structure analysis program FRAGSTATS and soil erosion transition matrices from 1958 to1975, from 1975 to 1982, and from 1982 to 1996 by using the CROSSTAB module in IDRISI software. Quantitative analysis of soil erosion patterns and its dynamic evolution were conducted at the class level and landscape level for individual erosion grades and the total erosion. The results indicated that soil erosion in Xingguo County reduced considerably from 1958 to 1996. During that period, there were three pronounced phases, including the exacerbation phase from 1958 to 1975, natural alleviation phase from 1975 to 1982, and overall alleviation phase from 1982 to 1996. The area of seriously eroded land decreased significantly. By 1996, the area of land with no significant soil erosion had reached about 74.6% of the total land area of the County, and the serious soil erosion problem had basically been controlled.

Xu, Zhongmin, Cheng,G.D., Zhang, Z., Su, Z., & J. Loomis “Applying contingent valuation in China to measure the total economic value of restoring ecosystem services in Ejina region," Ecological Economics 1-14, December, 2002.

Abstract: This paper reports an attempt to apply the Contingent Valuation Method (CVM) in rural China. The CVM was used to obtain estimates of willingness to pay for restoring Ejina ecosystem services. In our survey, we used a payment card format and a 12-page survey booklet with maps depicting the reasons why Ejina ecosystem deteriorated, the means by which ecosystem services could be restored from their current level. We used an in-person interview along with the survey booklet. We employed a parametric model to estimate the benefits of restoring Ejina ecosystem. Results from 700 in-person interviews indicate that households would pay an average of 19.37 (RMB) per year with 20.78 per household for the main river area, and 16.41 per household for the rest of Hei basin. The aggregate benefit to residents of the Hei basin is 8.84 million annually for 20 years. Taking into account an environmental discount rate calculated by using respondent’s equivalent utility between periodical payments and lump sum payments, the present value of aggregate benefit of restoring Ejina ecosystem is 55.33 million. These results suggest that the general public in Hei Valley would be willing to pay to restore the Ejina ecosystem, although this amount is substantially less than the estimated costs of restoration.