Effects of reclamation of natural wetlands to a rice paddy on dissolved carbon dynamics in the Sanjiang Plain, Northeastern China

Abstract Natural wetlands play an important role in the global carbon cycle, and loss of dissolved carbon through water has been indicated as one of the most important carbon sources for riverine ecosystems. During the last century, a large natural wetland area was reported to be converted to other land use types such as rice paddy land around the world. In this study, we explored the dynamics of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) in two natural freshwater wetlands and a rice paddy field, which was reclaimed from the natural wetlands in the Sanjiang Plain, Northeastern China, during the growing season (May–October) of 2009. The DOC and DIC concentrations in the two ecosystems were significantly different ( P Deyeuxia angustifolia and Carex lasiocarpa wetlands were 49.88 ± 5.44 and 27.97 ± 1.69 mg/L, respectively, while it was only 8.63 ± 2.54 mg/L in the rice paddy field. Specific ultra-violet light absorption at 254 nm (SUVA 254 ) of DOC increased by an average of 19.54% in the surface water from the natural wetlands to rice paddy, suggesting that DOC mobilized in the natural wetlands was more aromatic than that in the rice paddy field. The mean DIC concentration in surface water of the rice paddy was 5.25 and 5.04 times higher than that in the natural D. angustifolia and C. lasiocarpa wetlands, respectively. The average ratio of DIC to dissolved total carbon (DTC) for the water sampled from the artificial drainage ditch in the rice paddy field was 61.82%, while it was 14.75% from the nearby channel of natural wetlands. The significant differences in dissolved carbon concentration in surface water and channels originating from different land use types suggested that reclamation of natural wetlands to rice paddy field would reduce DOC runoff and increase the DIC concentration to adjacent watersheds. Our study results for the changed pattern in dissolved carbon after the natural wetland was transformed to paddy field could have important implications for studying the impacts of the large-scale land use change to carbon cycle and management.

[1]  P. Naden,et al.  Trends in Dissolved Organic Carbon in UK Rivers and Lakes , 2004 .

[2]  T. Burt,et al.  The effect of severe drought on the dissolved organic carbon (DOC) concentration and flux from British rivers , 2008 .

[3]  G. Bengtsson,et al.  Dissolved organic carbon dynamics in the peat–streamwater interface , 2004 .

[4]  T. Burt,et al.  Time series analysis of long‐term river dissolved organic carbon records , 2004 .

[5]  Tim R. Moore,et al.  Environmental chemistry: Browning the waters , 2006, Nature.

[6]  K. Gardner,et al.  Variation in DOC and trace metal concentration along the heavily urbanized basin in Kathmandu Valley, Nepal , 2009 .

[7]  W. Kelly.  Heterogeneities in ground-water geochemistry in a sand aquifer beneath an irrigated field , 1997 .

[8]  G. Mills,et al.  Impacts of elevated atmospheric ozone on peatland below-ground DOC characteristics. , 2009 .

[9]  Wang Yi-yong,et al.  Characteristics and estimation of CH4, N2O emissions from cold paddy field in the Sanjiang Plain , 2008 .

[10]  H. Tian,et al.  Convergence in the relationship of CO2 and N2O exchanges between soil and atmosphere within terrestrial ecosystems , 2008 .

[11]  H. Tian,et al.  China's changing landscape during the 1990s: Large‐scale land transformations estimated with satellite data , 2005 .

[12]  J. Neff,et al.  Snowmelt dominance of dissolved organic carbon in high‐latitude watersheds: Implications for characterization and flux of river DOC , 2006 .

[13]  A. P. Abaimov,et al.  Dissolved Organic Carbon in Upland Forested Watersheds Underlain by Continuous Permafrost in Central Siberia , 2006 .

[14]  D. J. Dowrick,et al.  Export of dissolved organic carbon from peatlands under elevated carbon dioxide levels , 2004, Nature.

[15]  S. Thacker,et al.  Development and application of functional assays for freshwater dissolved organic matter. , 2005, Water research.

[16]  P. Camargo,et al.  Effects of Urban Sewage on Dissolved Oxygen, Dissolved Inorganic and Organic Carbon, and Electrical Conductivity of Small Streams along a Gradient of Urbanization in the Piracicaba River Basin , 2002 .

[17]  M. Chantigny,et al.  Dissolved organic carbon in runoff and tile-drain water under corn and forage fertilized with hog manure. , 2007, Journal of environmental quality.

[18]  H. Tian,et al.  Spatial and temporal patterns of China's cropland during 1990¿2000: An analysis based on Landsat TM data , 2005 .

[19]  J. Macquaker,et al.  Influence of climate and hydrology on carbon in an early Miocene peatland , 2007 .

[20]  T. Ellis,et al.  The interactive effects of elevated carbon dioxide and water table draw-down on carbon cycling in a Welsh ombrotrophic bog , 2009 .

[21]  C. Driscoll,et al.  Landscape influences on aluminium and dissolved organic carbon in streams draining the Hubbard Brook valley, New Hampshire, USA , 2005 .

[22]  J. Lewandowski,et al.  Nutrient retention and release in a floodplain's aquifer and in the hyporheic zone of a lowland river , 2010 .

[23]  F. E. Egler.  Ecosystems of the World , 1960 .

[24]  Mark M. Brinson,et al.  Concepts in wetland ecology , 1990 .

[25]  P. Kortelainen,et al.  Export of DOM from Boreal Catchments: Impacts of Land Use Cover and Climate , 2005 .

[26]  G. Guggenberger,et al.  Mobilization and immobilization of dissolved organic matter in forest soils , 1998 .

[27]  M. Wong,et al.  Nitrogen and phosphate mass balance in a sub-surface flow constructed wetland for treating municipal wastewater , 2008 .

[28]  Kimberley M. Driscoll,et al.  Chemical response of lakes in the Adirondack Region of New York to declines in acidic deposition. , 2003, Environmental science & technology.

[29]  N. Caraco,et al.  Carbon in catchments: connecting terrestrial carbon losses with aquatic metabolism , 2001 .

[30]  C. Bryant,et al.  Sources of organic and inorganic carbon in a headwater stream: Evidence from carbon isotope studies , 2001 .

[31]  M. A. Arain,et al.  Concentrations and fluxes of dissolved organic carbon in an age-sequence of white pine forests in Southern Ontario, Canada , 2007 .

[32]  N. Oh,et al.  Anthropogenically enhanced fluxes of water and carbon from the Mississippi River , 2008, Nature.

[33]  Pete Smith,et al.  Carbon losses from soil and its consequences for land-use management. , 2007, The Science of the total environment.

[34]  A. Baker,et al.  Dissolved and total organic and inorganic carbon in some British rivers , 2008 .

[35]  J. Holden,et al.  Drain blocking: an effective treatment for reducing dissolved organic carbon loss and water discolouration in a drained peatland. , 2006, The Science of the total environment.

[36]  Maria Strack,et al.  Effect of water table drawdown on peatland dissolved organic carbon export and dynamics , 2008 .

[37]  Liu Huanjun,et al.  Land Use Change in Sanjiang Plain and Its Driving Forces Analysis since 1954 , 2008 .

[38]  E. Simonov,et al.  Amur-Heilong river basin reader , 2008 .

[39]  J. Cole,et al.  Increase in the Export of Alkalinity from North America's Largest River , 2003, Science.

[40]  Chris Freeman,et al.  Climatic change and the release of immobilized nutrients from Welsh riparian wetland soils , 1993 .

[41]  B. Bergamaschi,et al.  Evaluation of specific ultraviolet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon. , 2003, Environmental science & technology.

[42]  S. Sabater,et al.  Biofilm Structure and Function and Possible Implications for Riverine DOC Dynamics , 2004, Microbial Ecology.

[43]  M. Sommer,et al.  Influence of soil pattern on matter transport in and from terrestrial biogeosystems- : A new concept for landscape pedology , 2006 .

[44]  Ji‐Hyung Park,et al.  Controls on the dynamics of dissolved organic matter in soils: a review. , 2000 .

[45]  E. Schuur,et al.  Seasonal changes in the age and structure of dissolved organic carbon in Siberian rivers and streams , 2006 .

[46]  D. Monteith,et al.  Long-term increases in surface water dissolved organic carbon: observations, possible causes and environmental impacts. , 2005, Environmental pollution.

[47]  Yuesi Wang,et al.  Study on dissolved organic carbon in precipitation in Northern China. , 2010 .

[48]  L. Tranvik,et al.  Integrating aquatic carbon fluxes in a boreal catchment carbon budget , 2007 .

[49]  郑循华 宋长春 赵志春 王毅勇,et al.  三江平原湿地CH4、N2O的地-气交换特征 , 2006 .

[50]  Qingliang Zhao,et al.  Behavior and characteristics of DOM during a laboratory-scale horizontal subsurface flow wetland treatment: Effect of DOM derived from leaves and roots , 2009 .

[51]  Josef Hejzlar,et al.  The apparent and potential effects of climate change on the inferred concentration of dissolved organic matter in a temperate stream (the Malse River, South Bohemia). , 2003, The Science of the total environment.

[52]  T. Moore,et al.  Sources and sinks of dissolved organic carbon in a forested swamp catchment , 1991 .