Based on the results of water sample measurements of nutrient concentrations at th e Datong Station of the Changjiang River from 1998 to 1999, combined w ith historical data of water quality, seasonal variations of nu...Based on the results of water sample measurements of nutrient concentrations at th e Datong Station of the Changjiang River from 1998 to 1999, combined w ith historical data of water quality, seasonal variations of nutrient concentrations and nutrient transports are discussed.The following results have been obtained: (1) the fluxes of the nitrate nitrogen, ammonium nitrogen and nitrite nitrogen increased by time-series from 1962 to 1990 , even if runoff volume had a little variation; (2) the concentrations and fluxes of the dissolved inorganic nitrogen (DIN) and dissolved in organic phosphorus (DIP) increased notably with time, but those of the dissolved silicon (DSI) decreased pronouncedly; and (3) the concentration s and fluxes changed synchronously with time between the Datong Station a nd the Changjiang Estuary.展开更多
同时采用有效态和欧共体BCR(the Community Bureau of Reference)三步提取法对0-20 cm和20-40 cm土层中Ca,Mg,Fe,Zn,Cu,Mn进行形态分析,探索燕山山区板栗土壤中微量营养元素活性、形态分布特征和迁移能力。结果表明,栗粮间作会影响板栗...同时采用有效态和欧共体BCR(the Community Bureau of Reference)三步提取法对0-20 cm和20-40 cm土层中Ca,Mg,Fe,Zn,Cu,Mn进行形态分析,探索燕山山区板栗土壤中微量营养元素活性、形态分布特征和迁移能力。结果表明,栗粮间作会影响板栗对营养元素的吸收,且两层土壤中各元素活性相差不大;板栗纯林中0-20 cm土层的Cu,Zn活性明显高于20-40 cm土层;淋溶褐土和褐土性土两种土壤亚类,不同栽培制度对微量营养元素在板栗土壤中的形态分布特征影响不大。Cu,Zn,Fe主要以残渣态存在,Mn主要以可还原态和残渣态存在,且弱酸提取态高于其它元素。板栗土壤中元素的迁移能力排序为:Ca>Mg>Mn>Cu>Zn>Fe。展开更多
基金National Natural Science Foundation of China,No.39790110
文摘Based on the results of water sample measurements of nutrient concentrations at th e Datong Station of the Changjiang River from 1998 to 1999, combined w ith historical data of water quality, seasonal variations of nutrient concentrations and nutrient transports are discussed.The following results have been obtained: (1) the fluxes of the nitrate nitrogen, ammonium nitrogen and nitrite nitrogen increased by time-series from 1962 to 1990 , even if runoff volume had a little variation; (2) the concentrations and fluxes of the dissolved inorganic nitrogen (DIN) and dissolved in organic phosphorus (DIP) increased notably with time, but those of the dissolved silicon (DSI) decreased pronouncedly; and (3) the concentration s and fluxes changed synchronously with time between the Datong Station a nd the Changjiang Estuary.
文摘同时采用有效态和欧共体BCR(the Community Bureau of Reference)三步提取法对0-20 cm和20-40 cm土层中Ca,Mg,Fe,Zn,Cu,Mn进行形态分析,探索燕山山区板栗土壤中微量营养元素活性、形态分布特征和迁移能力。结果表明,栗粮间作会影响板栗对营养元素的吸收,且两层土壤中各元素活性相差不大;板栗纯林中0-20 cm土层的Cu,Zn活性明显高于20-40 cm土层;淋溶褐土和褐土性土两种土壤亚类,不同栽培制度对微量营养元素在板栗土壤中的形态分布特征影响不大。Cu,Zn,Fe主要以残渣态存在,Mn主要以可还原态和残渣态存在,且弱酸提取态高于其它元素。板栗土壤中元素的迁移能力排序为:Ca>Mg>Mn>Cu>Zn>Fe。