A regional model of vegetation dynamics was revised to include land use as a constraint to vegetation dynamics and primary production processes. The model was applied to a forest transect in eastern China (NSTEC, Nort...A regional model of vegetation dynamics was revised to include land use as a constraint to vegetation dynamics and primary production processes. The model was applied to a forest transect in eastern China (NSTEC, North-South transect of eastern China) to investigate the responses of the transect to possible future climatic change. The simulation result indicated that land use has profound effects on vegetation transition and primary production. In particular, land use reduced competition among vegetation classes and tended to result in less evergreen broadleaf forests but more shrubs and grasses in the transect area. The simulation runs with land use constraint also gave much more realistic estimation about net primary productivity as well as responses of the productivity to future climatic change along the transect. The simulations for future climate scenarios projected by general circulation models (GCM) with doubled atmospheric CO2 concentration predicted that deciduous broadleaf forests would increase, but conifer forests, shrubs and grasses would decrease. The overall effects of doubling CO2 and climatic changes on NSTEC were to produce an increased net primary productivity (NPP) at equilibrium for all seven GCM scenarios. The predicted range of NPP variation in the north is much larger than that in the south.展开更多
Two ecotypes of Elsholtzia, Elsholtzia splendens and E. argyi, are dominantplants growing on Cu and Pb-Zn smelters, respectively. Samples of the two ecotypes and thecorresponding soils from fields of a copper mining a...Two ecotypes of Elsholtzia, Elsholtzia splendens and E. argyi, are dominantplants growing on Cu and Pb-Zn smelters, respectively. Samples of the two ecotypes and thecorresponding soils from fields of a copper mining area and a Pb-Zn mining area ofZhejiang Province,China, were analyzed to investigate Cu or Zn tolerance of these two ecotypes. Effects of nine Culevels (0, 5, 10, 20, 40, 80, 160, 240 and 320 mg Cu L^(-1) as CuSO_4 centre dot 5H_O) on growth anduptake, translocation and accumulation of Cu in these two ecotypes were examined in a solutionculture experiment. The experimental results showed that dry weights (DW) of shoots and roots weredepressed, and growth of E. splendens was less depressed than that of E. argyi when treated with>= 5mg Cu L^(-1). Concentrations of Cu in shoots of E. splendens and E. argyi exceeded 1000 mg kg^(-1)DW at >= 40 mg Cu L^(-1). The maximum Cu accumulated in the shoots of Cu-treated E. splendens and E.argyi reached 101 and 142 mu g plant^(-1). Furthermore, analysis of plant samples from the fieldsshowed that these two ecotypes can tolerant excess heavy metals and produced high dry matter, and E.splendens can accumulate 11.7 mg Cu plant^(-1) grown on the Cu smelter. Therefore, E. splendens andE.argyi could be good plants for phytoremediation.展开更多
This paper is to establish a nitrogen and phosphorus nutrients cycle-based numerical model of ecological dynamics for Xiamen Bay on the basis of the existing three-dimensional barocline hydrodynamic model. The calcula...This paper is to establish a nitrogen and phosphorus nutrients cycle-based numerical model of ecological dynamics for Xiamen Bay on the basis of the existing three-dimensional barocline hydrodynamic model. The calculation results show that the estuarine district of Jiulongjiang estuary has the highest inorganic nitrogen concentration followed by the West Harbor, which demonstrates that Jiulongjiang River is the main input source of inorganic nitrogen in Xiamen Bay. The West Harbor has relatively high concentration of nutrients caused by the huge land pollution emission and its own poor water exchange capacity; while the distribution rules of phytoplankton biomass correspond with those of phosphates, demonstrating Xiamen Bay＇s phytoplankton controlled by phosphorus; the haloplankton biomass differs slightly, presenting the gradual reduction from the interior part to the exterior part of the bay.展开更多
文摘A regional model of vegetation dynamics was revised to include land use as a constraint to vegetation dynamics and primary production processes. The model was applied to a forest transect in eastern China (NSTEC, North-South transect of eastern China) to investigate the responses of the transect to possible future climatic change. The simulation result indicated that land use has profound effects on vegetation transition and primary production. In particular, land use reduced competition among vegetation classes and tended to result in less evergreen broadleaf forests but more shrubs and grasses in the transect area. The simulation runs with land use constraint also gave much more realistic estimation about net primary productivity as well as responses of the productivity to future climatic change along the transect. The simulations for future climate scenarios projected by general circulation models (GCM) with doubled atmospheric CO2 concentration predicted that deciduous broadleaf forests would increase, but conifer forests, shrubs and grasses would decrease. The overall effects of doubling CO2 and climatic changes on NSTEC were to produce an increased net primary productivity (NPP) at equilibrium for all seven GCM scenarios. The predicted range of NPP variation in the north is much larger than that in the south.
基金Project supported by the National Natural Science Foundation of China (No. 29977017)
文摘Two ecotypes of Elsholtzia, Elsholtzia splendens and E. argyi, are dominantplants growing on Cu and Pb-Zn smelters, respectively. Samples of the two ecotypes and thecorresponding soils from fields of a copper mining area and a Pb-Zn mining area ofZhejiang Province,China, were analyzed to investigate Cu or Zn tolerance of these two ecotypes. Effects of nine Culevels (0, 5, 10, 20, 40, 80, 160, 240 and 320 mg Cu L^(-1) as CuSO_4 centre dot 5H_O) on growth anduptake, translocation and accumulation of Cu in these two ecotypes were examined in a solutionculture experiment. The experimental results showed that dry weights (DW) of shoots and roots weredepressed, and growth of E. splendens was less depressed than that of E. argyi when treated with>= 5mg Cu L^(-1). Concentrations of Cu in shoots of E. splendens and E. argyi exceeded 1000 mg kg^(-1)DW at >= 40 mg Cu L^(-1). The maximum Cu accumulated in the shoots of Cu-treated E. splendens and E.argyi reached 101 and 142 mu g plant^(-1). Furthermore, analysis of plant samples from the fieldsshowed that these two ecotypes can tolerant excess heavy metals and produced high dry matter, and E.splendens can accumulate 11.7 mg Cu plant^(-1) grown on the Cu smelter. Therefore, E. splendens andE.argyi could be good plants for phytoremediation.
文摘This paper is to establish a nitrogen and phosphorus nutrients cycle-based numerical model of ecological dynamics for Xiamen Bay on the basis of the existing three-dimensional barocline hydrodynamic model. The calculation results show that the estuarine district of Jiulongjiang estuary has the highest inorganic nitrogen concentration followed by the West Harbor, which demonstrates that Jiulongjiang River is the main input source of inorganic nitrogen in Xiamen Bay. The West Harbor has relatively high concentration of nutrients caused by the huge land pollution emission and its own poor water exchange capacity; while the distribution rules of phytoplankton biomass correspond with those of phosphates, demonstrating Xiamen Bay＇s phytoplankton controlled by phosphorus; the haloplankton biomass differs slightly, presenting the gradual reduction from the interior part to the exterior part of the bay.
