The variation of soil enzyme activities under a Karst forest was studied by comparing soil enzyme activity and soil nutrient content under different vegetation types and different ages of Zanthoxylum planispinum var.d...The variation of soil enzyme activities under a Karst forest was studied by comparing soil enzyme activity and soil nutrient content under different vegetation types and different ages of Zanthoxylum planispinum var.dingtanensis forest in Beipan River Karst gorge district.The Z.planispinum var.dingtanensis forest was the phase of the forest succession.The results indicated that,with increase of degradation intensity,the soil enzyme activity declined.The soil enzyme activity was in an order of forest>shrubbery(Z.planispinum var.dingtanensis forest)>bush>grassland.The soil enzyme activity declined obviously in the process of degradation.The soil enzyme activity of sucrase,amylase,proteinase,urease,phosphates,polyphen oxidase in the forest was higher than bush and grassland’s.The Z.planispinum var.dingtanensis forest was on the mid of this process.Fertilization was able to stave off the soil’s degeneration in short time.However the long-term effect of fertilization needs to be inspected.展开更多
Using the Guancun River, an underground stream-fed river, in Rong＇an County of Guangxi, China as a case study, the daily biochemical cycle was examined in this paper based on the data collected a weeklong via high re...Using the Guancun River, an underground stream-fed river, in Rong＇an County of Guangxi, China as a case study, the daily biochemical cycle was examined in this paper based on the data collected a weeklong via high resolution data logger monitoring and high-frequency sampling. Furthermore, the loss of inorganic carbon along its flow path was estimated. Results show that chemical components of the groundwater input are quite stable, showing little change extent; while all of the chemical parameters from two downstream monitoring stations show diel variation over the monitoring period, suggesting that plant activity in the river has a strong influence on water chemistry of the river. The comparison of the input fluxes from the groundwater with the output fluxes of HCO~ estimated at the downstream monitoring station during the high-frequency sampling period shows a strong decrease of HCO~, indicating that the river is losing inorganic carbon along its flow path. The loss is estimated to be about 1,152 mmol/day/m of HCO~ which represent about 94.9 kg/day of inorganic carbon along the 1,350 m section of the Guancun River. It means that HCO~ entering the river from karst underground stream was either consumed by plants or trapped in the authigenic calcite and thus constitutes a natural sink of carbon for the Guancun karst system.展开更多
文摘The variation of soil enzyme activities under a Karst forest was studied by comparing soil enzyme activity and soil nutrient content under different vegetation types and different ages of Zanthoxylum planispinum var.dingtanensis forest in Beipan River Karst gorge district.The Z.planispinum var.dingtanensis forest was the phase of the forest succession.The results indicated that,with increase of degradation intensity,the soil enzyme activity declined.The soil enzyme activity was in an order of forest>shrubbery(Z.planispinum var.dingtanensis forest)>bush>grassland.The soil enzyme activity declined obviously in the process of degradation.The soil enzyme activity of sucrase,amylase,proteinase,urease,phosphates,polyphen oxidase in the forest was higher than bush and grassland’s.The Z.planispinum var.dingtanensis forest was on the mid of this process.Fertilization was able to stave off the soil’s degeneration in short time.However the long-term effect of fertilization needs to be inspected.
基金supported by the Special Fund for Public Benefit Scientific Research of Ministry of Land and Resources of China(No.201111022)IGCP/SIDA 598the China Geological Survey Projects (No.1212011087122,No.1212011220230)
文摘Using the Guancun River, an underground stream-fed river, in Rong＇an County of Guangxi, China as a case study, the daily biochemical cycle was examined in this paper based on the data collected a weeklong via high resolution data logger monitoring and high-frequency sampling. Furthermore, the loss of inorganic carbon along its flow path was estimated. Results show that chemical components of the groundwater input are quite stable, showing little change extent; while all of the chemical parameters from two downstream monitoring stations show diel variation over the monitoring period, suggesting that plant activity in the river has a strong influence on water chemistry of the river. The comparison of the input fluxes from the groundwater with the output fluxes of HCO~ estimated at the downstream monitoring station during the high-frequency sampling period shows a strong decrease of HCO~, indicating that the river is losing inorganic carbon along its flow path. The loss is estimated to be about 1,152 mmol/day/m of HCO~ which represent about 94.9 kg/day of inorganic carbon along the 1,350 m section of the Guancun River. It means that HCO~ entering the river from karst underground stream was either consumed by plants or trapped in the authigenic calcite and thus constitutes a natural sink of carbon for the Guancun karst system.
