Phosphorus fractions and alkaline phosphatase activity in sediments of a large eutrophic Chinese lake (Lake Taihu)

Abstract

Spatial, vertical, and seasonal variations in phosphorus fractions and in alkaline phosphatase activity (APA) were investigated in sediments in a large-shallow eutrophic Chinese lake (Lake Taihu) in [2003][2004]. The phosphorus content was highest in the most seriously polluted lake area. Iron-bound phosphorus (Fe(OOH)*P) dominated (47% on average) among the phosphorus fractions determined according to Golterman (Hydrobiologia 335:87-95, 1996). Notably, organically-bound P comprised a further significant additional portion (acid-soluble + hot NaOH-extractable organic P = 25%), which was highest at the most polluted sites. The Fe(OOH)*P content was the lowest in spring (April, 2004), suggesting that degradation of organic matter led to the release of iron-bound phosphates. Sediment APA showed a significant positive relationship with both organically-bound P and Fe(OOH)*P. Consequently, organically-bound P is an important portion of the sediment phosphorus in Lake Taihu. It is mainly derived from freshly-settled autochthonous particles and from external discharges. Organicallybound P induces APA and may lead to the release of bioavailable phosphates from the organic sediments, thereby accelerating lake eutrophication.

Isolation and Characterization of Organic Phosphorus-Mineralizing Bacteria in Sediment of a Chinese Large Shallow Eutrophic Lake (Lake Taihu)

“…Moreover, in the sediment of Lake Taihu, the organically bound phosphate significantly related not only to the OPB numbers ), but also to APA (Zhou et al 2008). A significant positive relationship was further found between APA and OPB numbers ( Figure 5).…”

“…Besides, the organicallybound phosphorus (acidsoluble+hot NaOH-extractable organic phosphorus) also accounted for a larger part of the sediment phosphorus around the site 1 (Zhou et al 2008). Consistently, in the sediment of Chinese Guanting reservoir, the number of phosphorusdissolving/discomposing bacteria was directly correlated to the phosphorus content in different sediment depths (Li et al 2005).…”

“…For example, in June and at the three sampling sites, the OPB in a significantly high number were the main contributor to the peaks of chlorophyll a concentration ). Quantitatively, sediment organically bound phosphorus significantly related to both the OPB numbers ) and APA (Zhou et al 2008).…”

Enhancement of sediment phosphorus release during a tunnel construction across an urban lake (Lake Donghu, China)

“…5, Fe(OOH)∼P accounted for the largest part of the sediment phosphorus fractions, echoing the previous study in the same lake (Zhou et al 2001). Furthermore, in sediment of a large shallow eutrophic Chinese lake (Lake Taihu), Fe(OOH)∼P dominated (47 % on average) and its content was the lowest in spring, suggesting that the degradation of organic matter led to the release of iron-bound phosphates (Zhou et al 2008). Additionally, in Lake Donghu, ASOP were probably important in supplying the enzymatic substrate into interstitial water (Zhou et al 2001), paralleling with the highest SRP concentration in March of 1995 in Tangling basin of the lake (Zhou et al 2002).…”

Vertical distribution and release characteristics of phosphorus forms in the sediments from the river inflow area of Dianchi Lake, China

“…Furthermore, with greater phytoplankton biomass (or organic substances) accumulated in eutrophic lake sediments, activities of phosphatase (e.g. alkaline phosphatase) are usually greater in sediments [33,34]. Therefore, in Dianchi Lake sediments, the higher 0.00 1.00 2.00 3.00 4.00 A1 A2 A3 A4 A5 A6 A7 A8 B1 B2 B3 B4 B5 B6 B7 B8 C1 C2 C3 C4 C5 C6 C7 C8 D1 D2 D3 D4 D5 D6 D7 D8 E1 E2 E3 E4 E5 E6 E7 E8…”