Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll （HNLC） ...Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll （HNLC） seawaters. A study of inorganic carbon （IC） forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms： NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon （TIC）. However, NH3 ·H2O, NH2OH · HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon, pore water, iron, pH, redox potential （Eh） and sulfur potential（Es） in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH· HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3· H2O forms of IC ; the influence of Fe^2＋ was higher than Fe^3＋ and its effect on NH3 ·H2O form was stronger than on NaCl and NaOH forms.展开更多
In studying sand beach erosion and protection tactics in Liaoning Province, the authors calculated the wavedata of 27 a Period (1963-1991) at Bayuquan Observation Station in Liaodong Gulf. Together with the beach leve...In studying sand beach erosion and protection tactics in Liaoning Province, the authors calculated the wavedata of 27 a Period (1963-1991) at Bayuquan Observation Station in Liaodong Gulf. Together with the beach levellingsand some simple marking stakes monitoring and by having the aid of local annals, the paper analysed the present situationsof the coastline and the causes of sand coastal recession and serious consequences, and then discussed the dynamic processof alongshore sand transport. Simultaneously, based on alongshore sand transport model, oneline cut-and-fill theory anddynamical water model(sea level rise), the authors preliminary estimated beach process for the future in the area.Recently, the coastline is being eroded and 2/3 of the sand coast is subjected to erosion, which the recession rate ofthe individual sector exceed 7. 0 m/a. Coastal erosion has threatened villages, roads, factories and tourist resources. Sealevel rises and the decreasing amount of materials by rivers discharged into the sea and the activities of man, made coast line recession rate accelerate, and cause a great loss of land in the area.展开更多
文摘Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll （HNLC） seawaters. A study of inorganic carbon （IC） forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms： NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon （TIC）. However, NH3 ·H2O, NH2OH · HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon, pore water, iron, pH, redox potential （Eh） and sulfur potential（Es） in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH· HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3· H2O forms of IC ; the influence of Fe^2＋ was higher than Fe^3＋ and its effect on NH3 ·H2O form was stronger than on NaCl and NaOH forms.
文摘In studying sand beach erosion and protection tactics in Liaoning Province, the authors calculated the wavedata of 27 a Period (1963-1991) at Bayuquan Observation Station in Liaodong Gulf. Together with the beach levellingsand some simple marking stakes monitoring and by having the aid of local annals, the paper analysed the present situationsof the coastline and the causes of sand coastal recession and serious consequences, and then discussed the dynamic processof alongshore sand transport. Simultaneously, based on alongshore sand transport model, oneline cut-and-fill theory anddynamical water model(sea level rise), the authors preliminary estimated beach process for the future in the area.Recently, the coastline is being eroded and 2/3 of the sand coast is subjected to erosion, which the recession rate ofthe individual sector exceed 7. 0 m/a. Coastal erosion has threatened villages, roads, factories and tourist resources. Sealevel rises and the decreasing amount of materials by rivers discharged into the sea and the activities of man, made coast line recession rate accelerate, and cause a great loss of land in the area.
