What drives the evolution of the sedimentary phosphorus cycle?

Abstract

a b s t r a c tThe 'Chicken Creek' artificial catchment area, Welzow-South, E Germany, created to study processes and structures of initial ecosystem development, discharges into a small experimental lake (A =3805 m 2 , V= 3992 m 3 , z max = 2.4 m). This lake was man-made in 2005 and filled by natural surface runoff until January 2006. In summer 2006 and 2008, the actual development of sediments and the evolution of the phosphorus (P) cycle were studied. 19.7% of the original lake volume was filled by sediment within the first 3 years. A fine-grained sediment representing silt (6.3-63 mm) accumulated at high accretion rates at the deepest point (200 mm a À 1 , 0-24 mm week À 1 ) due to massive erosion in the catchment. The sediment is low in organic matter (2.5-5.2%) and total P (TP, 0.31-0.97 mg g À 1 ). Low amounts of P associated with degradable organic matter and surplus of metal hydroxides (Fe:P $ 40, Al:P $ 20) favor an efficient P binding and low dissolved P concentrations in pore water (1-107 mg l À 1 ).Hence, the mineral sediment quality and the low rates of P release (0.06 mg m À 2 d À 1 ) revealed that a lake at an initial stage of development has essentially no sedimentary P cycle compared to eutrophic shallow lakes. However, the increasing emersed and submersed macrophyte growth will control further lake succession by intensifying the internal nutrient cycling. The macrophytes drive the evolution of a sedimentary P cycle by mobilizing and translocating P, by accumulating carbon and thus by stimulating microbial and redox processes.

Vitality of aquatic plants and microbial activity of sediment in an oligotrophic lake (Lake Bohinj, Slovenia)

“…It is known that roots of studied species M. spicatum release oxygen that has profound affect on mineralization processes in the sediment (Laskov et al 2006). Kleeberg et al (2010) reported that macrophytes drive the evolution of a sedimentary P cycle by mobilizing and translocating P, by accumulating carbon, and thus by stimulating microbial and redox processes. The wellaerated sediment in Lake Bohinj enables rapid mineralization of organic matter and, in turn, sufficient nutrients for growth of macrophytes.…”

Pool of mobile and immobile phosphorus in sediments of the large, shallow Lake Peipsi over the last 100 years

“…The decomposition of OM, especially via iron and sulphate reduction, is crucial for the mobilisation of inorganic P, bound by sorption to iron hydroxide surfaces (Kleeberg et al 2010). Due to aerobic and anaerobic redox processes, not only organic C compounds but also organic P compounds are turned over (Turner et al 2005;Kleeberg et al 2010).…”

“…Due to aerobic and anaerobic redox processes, not only organic C compounds but also organic P compounds are turned over (Turner et al 2005;Kleeberg et al 2010). The low C/N ratios (<9) indicate that the NaOH extractable organic P compound groups included in the precipitate originate from autochthonous matter (Punning et al 2008).…”

Antioxidant Responses of Vallisneria asiatica to Eutrophic Sediments in Lake Taihu, China

“…Sediment particles smaller than 100 lm were used for all analyses and acid digestion. The proportion of organic matter (OM) in the sediment can be reflected by weight loss through combustion (450°C, 3 h) (Kleeberg et al 2010). To determine the metal and nutrient contents, sediment samples were digested by H 2 SO 4 and H 2 O 2 (Kleeberg et al 2010).…”

“…The proportion of organic matter (OM) in the sediment can be reflected by weight loss through combustion (450°C, 3 h) (Kleeberg et al 2010). To determine the metal and nutrient contents, sediment samples were digested by H 2 SO 4 and H 2 O 2 (Kleeberg et al 2010). Major elements such as P and metals were determined by Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES, Optima 5300DV).…”