This paper reports the absorption,accumulation,distribution and cycle of Cu,Pb,Zn,Cr and Ni in S.apetala+S.caseolaris,mangrove community at Futian Mangrove Nature Reserve of Shenzhen,The Cu,Pb,Zn,Cr and Ni contents in...This paper reports the absorption,accumulation,distribution and cycle of Cu,Pb,Zn,Cr and Ni in S.apetala+S.caseolaris,mangrove community at Futian Mangrove Nature Reserve of Shenzhen,The Cu,Pb,Zn,Cr and Ni contents in forest soil increase from bottom to surface layers,and the storage of the five heavy metals in the surface layer(depth0-30cm)is Zn>Pb>Ni>Cr>Cu.The concentration ability is S.caseolaris>S.apetala>K.candel.The existing accumulation of Cu,Pb,Zn,Cr and Ni in the community is 23019.63μg/m^2,23429.66μg/m^2.177870.42μg/m^2,6835.80μg/m^2,and 12995.22μg/m^2,respectively.The annual absorption is 6592.57μg/m^2,2664.80μg/m^2,23123.56μg/m^2,853.24μg/m^2,and 1990.95μg/m^2,respectively.The annual return is 3179.50μg/m^2,1300.65μg/m^2,7401.31μg/m^2,398.99μg/m^2,and 646.20μg/m^2 respectively.The annual net retention accumulation of Cu,Pb,Zn,Cr and Ni in the community is 3413.07μg/m^2,1364.15μg/m^2,15722.25μg/m^2,454.25μg/m^2,and 1344.75μg/m^2,respectively,The turn over periods of Cu,Pb,Zn,Cr and Ni are 8,19,15,18and 21 years,respectively.展开更多
The effects of five salt ingredients of sea water, KCl, NaCl, CaCl2, MgCl2 and MgSO4, on induction of cell prolif-eration in Sonneratia caseolaris were investigated. Proliferation was examined in tissue explants deriv...The effects of five salt ingredients of sea water, KCl, NaCl, CaCl2, MgCl2 and MgSO4, on induction of cell prolif-eration in Sonneratia caseolaris were investigated. Proliferation was examined in tissue explants derived from such as leaves, cotyledons, and hypocotyls using a small-scale liquid culture method. Addition of 12.5-25 mM of MgCl2 was unique in stimulating cell proliferation in all tissues of S. caseolaris. Otherwise, different effects of salts were observed among the three tissues. In hypocotyl culture, 25-50 mM of NaCl and CaCl2 stimulated cell divisions. Tolerance to 100 mM of MgSO4 was observed in leaves. Three osmotically active compounds commonly used in tissue culture, sorbitol, mannitol and glycinebetaine, were also tested to assess the importance of osmotic effects on cell proliferation. No significant stimulation by these was observed over a wide range of concentrations. Data were compared with those of cotyledon cultures of another mangrove, S. alba, which exhibits no stimulation by MgCl2, stimulation by KCl and tolerance to NaCl. Mechanisms for adaptation of mangrove plants to various and high salts were discussed by comparing the differences in reaction to salts in cultures of two Sonneratia mangrove species of the same genera growing different salt environment.展开更多
Developments adjacent to river, over the years, have impacted the ecological systems along riparian zones. This paper is to explore the changes occurring in a populated riparian zone. For over 35 years, the nipah swam...Developments adjacent to river, over the years, have impacted the ecological systems along riparian zones. This paper is to explore the changes occurring in a populated riparian zone. For over 35 years, the nipah swamps along the study site at the edge of Kuching city, Sarawak, Malaysia are subjected to human disturbances. Once a nipah forest is dominated by Nypa fruticans, the study site is being replaced by Sonneratia caseolaris—a mangrove forest. Both plants are indigenous to Southeast Asia region. We observe in the study site that Nypa fruticans, habitually a dominant species, is weakened when human disturbances are high, and leads to event taken over by Sonneratia caseolaris. We point out that Sonneratia caseolaris behaves intrusively rather than neighborly in disturbed systems. Here, we suggest that the plant also has high resistance towards human disturbances. This is a growing behavior contradictory to reports of Sonneratia caseolaris in natural systems.展开更多
文摘This paper reports the absorption,accumulation,distribution and cycle of Cu,Pb,Zn,Cr and Ni in S.apetala+S.caseolaris,mangrove community at Futian Mangrove Nature Reserve of Shenzhen,The Cu,Pb,Zn,Cr and Ni contents in forest soil increase from bottom to surface layers,and the storage of the five heavy metals in the surface layer(depth0-30cm)is Zn>Pb>Ni>Cr>Cu.The concentration ability is S.caseolaris>S.apetala>K.candel.The existing accumulation of Cu,Pb,Zn,Cr and Ni in the community is 23019.63μg/m^2,23429.66μg/m^2.177870.42μg/m^2,6835.80μg/m^2,and 12995.22μg/m^2,respectively.The annual absorption is 6592.57μg/m^2,2664.80μg/m^2,23123.56μg/m^2,853.24μg/m^2,and 1990.95μg/m^2,respectively.The annual return is 3179.50μg/m^2,1300.65μg/m^2,7401.31μg/m^2,398.99μg/m^2,and 646.20μg/m^2 respectively.The annual net retention accumulation of Cu,Pb,Zn,Cr and Ni in the community is 3413.07μg/m^2,1364.15μg/m^2,15722.25μg/m^2,454.25μg/m^2,and 1344.75μg/m^2,respectively,The turn over periods of Cu,Pb,Zn,Cr and Ni are 8,19,15,18and 21 years,respectively.
文摘The effects of five salt ingredients of sea water, KCl, NaCl, CaCl2, MgCl2 and MgSO4, on induction of cell prolif-eration in Sonneratia caseolaris were investigated. Proliferation was examined in tissue explants derived from such as leaves, cotyledons, and hypocotyls using a small-scale liquid culture method. Addition of 12.5-25 mM of MgCl2 was unique in stimulating cell proliferation in all tissues of S. caseolaris. Otherwise, different effects of salts were observed among the three tissues. In hypocotyl culture, 25-50 mM of NaCl and CaCl2 stimulated cell divisions. Tolerance to 100 mM of MgSO4 was observed in leaves. Three osmotically active compounds commonly used in tissue culture, sorbitol, mannitol and glycinebetaine, were also tested to assess the importance of osmotic effects on cell proliferation. No significant stimulation by these was observed over a wide range of concentrations. Data were compared with those of cotyledon cultures of another mangrove, S. alba, which exhibits no stimulation by MgCl2, stimulation by KCl and tolerance to NaCl. Mechanisms for adaptation of mangrove plants to various and high salts were discussed by comparing the differences in reaction to salts in cultures of two Sonneratia mangrove species of the same genera growing different salt environment.
文摘Developments adjacent to river, over the years, have impacted the ecological systems along riparian zones. This paper is to explore the changes occurring in a populated riparian zone. For over 35 years, the nipah swamps along the study site at the edge of Kuching city, Sarawak, Malaysia are subjected to human disturbances. Once a nipah forest is dominated by Nypa fruticans, the study site is being replaced by Sonneratia caseolaris—a mangrove forest. Both plants are indigenous to Southeast Asia region. We observe in the study site that Nypa fruticans, habitually a dominant species, is weakened when human disturbances are high, and leads to event taken over by Sonneratia caseolaris. We point out that Sonneratia caseolaris behaves intrusively rather than neighborly in disturbed systems. Here, we suggest that the plant also has high resistance towards human disturbances. This is a growing behavior contradictory to reports of Sonneratia caseolaris in natural systems.
