Desertification has been notably expanding in China in the recent decade, especially in North China where dust/sand storm （DSS） frequently assaulted local communities. Analyses in marine ecology found that the earth...Desertification has been notably expanding in China in the recent decade, especially in North China where dust/sand storm （DSS） frequently assaulted local communities. Analyses in marine ecology found that the earth ecosystem could be able to complement nutrient silicon for keeping sustainable development of marine ecosystem, and decreasing CO2 concentration in the atmosphere; as a result, the area of desertification would be enlarged. Modem human being activities have resulted in constant changes in the amount of silicon transport from land into sea, leading to oversupply of nitrogen and phosphorus but silicon in seawater. The proportion of nitrogen, phosphorus and silicon was seriously imbalanced and the limitation of silicon for phytoplankton growth has become more serious. The silicon deficiency has damaged the marine ecosystem in coastal regions and slowed down the carbon sedimentation in the atmosphere of the world. The authors believe that the continual discharge of CO2 into the atmosphere is the cause for the global warming including marine water temperature rise. Consequently, the earth ecosystem would have to trigger its complementary action to resume to the silicon balance by algae bloom in seawater for reducing air and water temperatures. In order to complement nutrient silicon into the sea, the ecosystem would transport silicon via the atmosphere; therefore, the desertification in the inner land is a natural reaction. As marine phytoplankton booming can reduce the CO2 concentration in the atmosphere and further ease the green-house effect, during this process, a large amount of silicon are demanded by the ecosystem, which human being are unable to stop desertification from happening but slow down the progress and ease the risk. Therefore, as an important role in earth ecosystem, people should reduce the CO2 discharge into the atmosphere first; then, the normal function of river transporting silicon must be restored. In this way, the CO2 in the atmosphere can be kept in balance, the global warming slowed down, marine ecosystem development sustained, the drought in inner land eased, and the desert gradually under-controlled.展开更多
The polychaete Perinereis aibuhitensis, a key species in estuarine ecosystems, can improve the culture condition of sediment. Endosulfan is an organochlorine pesticide used globally to control insects and mites; howev...The polychaete Perinereis aibuhitensis, a key species in estuarine ecosystems, can improve the culture condition of sediment. Endosulfan is an organochlorine pesticide used globally to control insects and mites; however, it is a source of pollution in aquaculture as a result of runoff or accidental release. In this study, we evaluated the toxicity of endosulfan to polychaeta and its ability to improve polluted sediment. Specifically, the effects of a series of endosulfan concentrations （0, 1.25, 2.5, 5, 10, 15, and 20 mg/L） were investigated, and the results indicated that the 24-h median lethal concentration （24-h LCs0） was 55.57 mg/L, while the 48-h median lethal concentration （48-h LCs0） was 15.56 mg/L, and the safe concentration was about 1.556 mg/L. In a 30-d exposure experiment, the animal specimen could decompose endosulfan effectively while improving endosulfan-polluted aquatic sediment.展开更多
The P-T stability conditions of gas hydrate in different systems （i.e., solution, silica sand, and marine sediment） were studied using multi-step decomposition method with our experimental equipment. The effects of ...The P-T stability conditions of gas hydrate in different systems （i.e., solution, silica sand, and marine sediment） were studied using multi-step decomposition method with our experimental equipment. The effects of different ions with various concentra- tions and sediment grains on the P-T stability conditions of gas hydrate were investigated. The results show that different ions have different influences on the phase equilibrium of gas hydrate. However, the influence of ions is in a similar trend： the larg- er the concentration, the bigger the P-T curve shifts to the left. For the silica sand, the influence of pore capillarity of coarse particles （〉 460 ~tm） can be negligible. The P-T curve measured in coarse silica is in agreement with that in pure water. How- ever, the influence of pore capillarity of fine particles （〈 35 μm） is significant. The maximum reduction value of temperature is 1.5 K for methane hydrate under stable state. The sediment from the South China Sea significantly affects the P-T stability conditions of methane hydrate, with an average reduction value of 1.9 K within the experimental conditions. This is mainly the result of both the pore water salinity and the pore capillarity of sediment. Because the pore water salinity is keeping diluted by the fresh water released from hydrate dissociation, the measured P-T stability points fall on different P-T curves with the de- creasing salinity.展开更多
基金Funded by the Director’s Foundation of the Beihai Monitoring Center and the State Oceanic Administration and Chinese Academy of Sciences (KZCX 2-207).
文摘Desertification has been notably expanding in China in the recent decade, especially in North China where dust/sand storm （DSS） frequently assaulted local communities. Analyses in marine ecology found that the earth ecosystem could be able to complement nutrient silicon for keeping sustainable development of marine ecosystem, and decreasing CO2 concentration in the atmosphere; as a result, the area of desertification would be enlarged. Modem human being activities have resulted in constant changes in the amount of silicon transport from land into sea, leading to oversupply of nitrogen and phosphorus but silicon in seawater. The proportion of nitrogen, phosphorus and silicon was seriously imbalanced and the limitation of silicon for phytoplankton growth has become more serious. The silicon deficiency has damaged the marine ecosystem in coastal regions and slowed down the carbon sedimentation in the atmosphere of the world. The authors believe that the continual discharge of CO2 into the atmosphere is the cause for the global warming including marine water temperature rise. Consequently, the earth ecosystem would have to trigger its complementary action to resume to the silicon balance by algae bloom in seawater for reducing air and water temperatures. In order to complement nutrient silicon into the sea, the ecosystem would transport silicon via the atmosphere; therefore, the desertification in the inner land is a natural reaction. As marine phytoplankton booming can reduce the CO2 concentration in the atmosphere and further ease the green-house effect, during this process, a large amount of silicon are demanded by the ecosystem, which human being are unable to stop desertification from happening but slow down the progress and ease the risk. Therefore, as an important role in earth ecosystem, people should reduce the CO2 discharge into the atmosphere first; then, the normal function of river transporting silicon must be restored. In this way, the CO2 in the atmosphere can be kept in balance, the global warming slowed down, marine ecosystem development sustained, the drought in inner land eased, and the desert gradually under-controlled.
基金Supported by Technology Development Program for Fisheries, Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea
文摘The polychaete Perinereis aibuhitensis, a key species in estuarine ecosystems, can improve the culture condition of sediment. Endosulfan is an organochlorine pesticide used globally to control insects and mites; however, it is a source of pollution in aquaculture as a result of runoff or accidental release. In this study, we evaluated the toxicity of endosulfan to polychaeta and its ability to improve polluted sediment. Specifically, the effects of a series of endosulfan concentrations （0, 1.25, 2.5, 5, 10, 15, and 20 mg/L） were investigated, and the results indicated that the 24-h median lethal concentration （24-h LCs0） was 55.57 mg/L, while the 48-h median lethal concentration （48-h LCs0） was 15.56 mg/L, and the safe concentration was about 1.556 mg/L. In a 30-d exposure experiment, the animal specimen could decompose endosulfan effectively while improving endosulfan-polluted aquatic sediment.
基金financially supported by the National Basic Research Program of China (Grant No. 2009CB219503)the National Natural Science Foundation of China (Grant No. 41072037)
文摘The P-T stability conditions of gas hydrate in different systems （i.e., solution, silica sand, and marine sediment） were studied using multi-step decomposition method with our experimental equipment. The effects of different ions with various concentra- tions and sediment grains on the P-T stability conditions of gas hydrate were investigated. The results show that different ions have different influences on the phase equilibrium of gas hydrate. However, the influence of ions is in a similar trend： the larg- er the concentration, the bigger the P-T curve shifts to the left. For the silica sand, the influence of pore capillarity of coarse particles （〉 460 ~tm） can be negligible. The P-T curve measured in coarse silica is in agreement with that in pure water. How- ever, the influence of pore capillarity of fine particles （〈 35 μm） is significant. The maximum reduction value of temperature is 1.5 K for methane hydrate under stable state. The sediment from the South China Sea significantly affects the P-T stability conditions of methane hydrate, with an average reduction value of 1.9 K within the experimental conditions. This is mainly the result of both the pore water salinity and the pore capillarity of sediment. Because the pore water salinity is keeping diluted by the fresh water released from hydrate dissociation, the measured P-T stability points fall on different P-T curves with the de- creasing salinity.
