Sedimentation rates, nitrogen and phosphorus retentions in the largest urban Lake Donghu, China

Abstract

Sediment core samples were collected in the largest urban Lake Donghu (Stations I and II) in China, and the activities of 210 Pb, 226 Ra and 137 Cs were measured by gamma-ray spectrometry. The sedimentation rates, calculated by 210 Pb constant rate of supply (CRS) model, ranged from 0.11 to 0.65 (average 0.39) cm . y -1 at Station I, and from 0.21 to 0.78 (average 0.46) cm . y -1 at Station II. Sedimentation rate calculated by 137 Cs as a time marker was 0.55 cm . y -1 at Station II. Based on the average sedimentation rate, we obtained 769 and 147 t . y -1 for nitrogen and phosphorus retentions in Lake Donghu sediments, respectively.

Carbon source/sink function of a subtropical, eutrophic lake determined from an overall mass balance and a gas exchange and carbon burial balance

“…Linear accumulation rates were 0.39 cm y À1 and 0.46 cm y À1 at Stations I and II, respectively (Table 2) (for more details see Yang et al, 2005b). As such, 40 cm cores represent records of 103 and 87 years at Stations I and II, respectively.…”

“…Agriculture and other types of land-cover change (conversion of forests and farmlands to cities, residential lands, and other man-made constructions) promote soil erosion, leading to an increase in sedimentation rates (Yang et al, 2005b) and the accumulation of particular organic carbon (POC) in lake sediments (Kortelainen et al, 2004). The high percentage of carbon retained in the system is also strongly related to the long lake water residence time (Marion and Brient, 1998).…”

Recent Sedimentation Rates of Shallow Lakes in the Middle and Lower Reaches of the Yangtze River: Patterns, Controlling Factors and Implications for Lake Management

“…Furthermore, human activities have been recognized as a key driver of sedimentation processes in the past century due to sewage input, land use changes and hydrological regulation [4,14,20]. Combined with natural environmental changes, human impacts pose a greater threat to the functioning of lake ecosystems by creating unfavorable lake environments such as increased sedimentation, reduced storage capacity, widespread flooding, often accompanied by enhanced nutrient levels and metal pollution [12,16,[21][22][23][24][25][26].…”

Spatio-Temporal Variations of Health Costs Caused by Chemical Fertilizer Utilization in China from 1990 to 2012

“…Fertilizers can alter the physical and chemical properties of soil by nitrate, sulfate, and nitrogen and cause heavy metal pollution by cadmium (Cd) [29,30], thus forming soil pollution. The runoff of phosphorus fertilizer from farmland catchment to waters can cause serious water pollution, leading to eutrophication and algal bloom [8,31].…”