Title of article :
Stress during development may cause fluctuating asymmetry (FA), i.e. non-directional and random deviations from perfect symmetry in otherwise symmetrical morphological traits. These deviations affect the phenotypic quality of an individual. We manipulated
Author/Authors :
Xuelei Wang، نويسنده , , C.M. Mannaerts، نويسنده , , Shengtian Yang، نويسنده , , Yunfei Gao، نويسنده , , Donghai Zheng، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2010
Pages :
9
From page :
3310
To page :
3318
Abstract :
Riparian ecosystems have critical impacts on controlling the non-point source pollution and maintaining the health of aquatic ecosystems. In this study, a process oriented soil denitrification model was extended with algorithms from a simple nitrogen (N) cycle model and coupled to land surface remote sensing data to enhance its performance in spatial and temporal prediction of gaseous N emissions from soils in the riparian buffer zone surrounding the Guanting reservoir (China). The N emission model is based on chemical and physical relationships that govern the heat budget, soil moisture variations and nitrogen movement in soils. Besides soil water and heat processes, it includes nitrification, denitrification and ammonia (NH3) volatilization. SPOT-5 and Landsat-5 TM satellite data were used to derive spatial land surface information and the temporal variation in land cover parameters was also used to drive the model. A laboratory-scale anaerobic incubation experiment was used to estimate the soil denitrification model parameters for the different soil types. An in situ field-scale experiment was conducted to calibrate and validate the soil temperature, moisture and nitrogen sub-models. An indirect method was used to verify simulated N emissions, resulting in a coefficient of determination of R2 = 0.83 between simulated and observed values. Then the model was applied to the whole riparian buffer zone catchment, using the spatial resolution (10 m) of the SPOT-5 image. Model sensitivity analysis showed that soil moisture was the most sensitive parameter for gaseous N emissions and soil denitrification was the main process affecting N losses to the atmosphere in the riparian area. From the aspect of land use management around the Guanting reservoir, the spatial structure and distribution of land cover and land use types in the riparian area should be adapted, to enhance faster ecological restoration of the wetland ecological system surrounding this strategically important water resource.
Keywords :
Remote sensing , Riparian zone , Nitrification , Denitrification , Gaseous nitrogen emissions , Ammonia volatilization
Journal title :
Science of the Total Environment
Serial Year :
2010
Journal title :
Science of the Total Environment
Record number :
986782
Link To Document :
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