A method for monitoring biological prodation of oxygen was used in the July 10September 15, 1995 study on the limiting nutrients in eight land-based 5 m × 5 m encloome equipped with waer stirrers in a Seawater po...A method for monitoring biological prodation of oxygen was used in the July 10September 15, 1995 study on the limiting nutrients in eight land-based 5 m × 5 m encloome equipped with waer stirrers in a Seawater pond in the study region (Yellow Sea). Chicken manare only, chicken manare combined with chemical fertilizers, and chemical fertilizers only, were put into the enclosures,respectively. The results showed that phosphorus was the lmiting nutrient; and that the optimal N: P ratio of the fertilizers was 7.25 - 7.54 (mean of 7.37), which was significantly lower than the ratio measured in the water, as phosphorus deposited is easily absorbed by sediments and is excessively uptaken by phytoplankton. The above optimal N: P ratio is suitable for daily fertization with combination fertilizer in the seawater ponds.展开更多
A laboratory experiment was undertaken to investigate the behaviour of boron at the seawater-air interface under air flow conditions. Dried air at 25 and 35℃ was passed over or bubbled through seawater at the same te...A laboratory experiment was undertaken to investigate the behaviour of boron at the seawater-air interface under air flow conditions. Dried air at 25 and 35℃ was passed over or bubbled through seawater at the same temperature. A combination of ice-chilled condensers and KOH impregnated cellulose fibre filters was used to collect boron from the reacted air. When air stripped of boron was passed over the seawater, boron was found in the reacted air, and its concentration was higher in the higher temperature test. In the tests where air was bubbled through seawater the concentration of boron in the reacted air was directly proportional to the air flow rate. In this situation the boron in the reacted air was mainly introduced as a spray of microdroplets. Isotopic analysis of the collected boron in the non-bubbled tests yields fractionation factors which demonstrate that the lighter isotope, 10B, is enriched in the reacted air. The size of the fractionation changes with temperature, ruling out a purely kinetic展开更多
文摘A method for monitoring biological prodation of oxygen was used in the July 10September 15, 1995 study on the limiting nutrients in eight land-based 5 m × 5 m encloome equipped with waer stirrers in a Seawater pond in the study region (Yellow Sea). Chicken manare only, chicken manare combined with chemical fertilizers, and chemical fertilizers only, were put into the enclosures,respectively. The results showed that phosphorus was the lmiting nutrient; and that the optimal N: P ratio of the fertilizers was 7.25 - 7.54 (mean of 7.37), which was significantly lower than the ratio measured in the water, as phosphorus deposited is easily absorbed by sediments and is excessively uptaken by phytoplankton. The above optimal N: P ratio is suitable for daily fertization with combination fertilizer in the seawater ponds.
基金The paper was considerably improved as a result of reviews by H. G. M. Eggenkamp and A.Spivack, for which the authors were very grateful. Y. M. Zhou (Institute of Salt Lakes, Xining, China) kindly assisted with the chlorine isotopic measurements. This
文摘A laboratory experiment was undertaken to investigate the behaviour of boron at the seawater-air interface under air flow conditions. Dried air at 25 and 35℃ was passed over or bubbled through seawater at the same temperature. A combination of ice-chilled condensers and KOH impregnated cellulose fibre filters was used to collect boron from the reacted air. When air stripped of boron was passed over the seawater, boron was found in the reacted air, and its concentration was higher in the higher temperature test. In the tests where air was bubbled through seawater the concentration of boron in the reacted air was directly proportional to the air flow rate. In this situation the boron in the reacted air was mainly introduced as a spray of microdroplets. Isotopic analysis of the collected boron in the non-bubbled tests yields fractionation factors which demonstrate that the lighter isotope, 10B, is enriched in the reacted air. The size of the fractionation changes with temperature, ruling out a purely kinetic