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在垂直压缩三维水动力模型的基础上,建立了包括无机碳、有机碳、二氧化碳、浮游植物态碳、浮游动物态碳、鱼类态碳、沉水植物态碳、底泥中的有机碳、底泥中的无机碳、底泥间隙水中的有机碳和无机碳等状态变量的太湖碳循环三维模型。并用2000年的实测资料进行了参数率定,用2003年的实测数据进行了校验。校验结果显示,绝大多数校验点次的实测值与模拟值间的误差均小于30%,4个校验点的模拟值和实测值的年平均误差均小于40%,由此可见,模型虽然仍需进一步完善,但其已经具有了一定的模拟精度,为太湖湖泊水体碳循环的研究奠定了基础。同时模型计算结果表明:湖泊水体碳循环对大气二氧化碳浓度的降低有正面作用。 相似文献
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通过用无量纲分析和线性回归方法对2002-2003年太湖4测点1000多组波浪资料的分析,给出了太湖不同时段风浪平均波高(H)与风区长度(F)、水深(d)、风速(v)6个关系模式.在此基础上,开展了模式的误差分析及与前人模式对比.结果表明,太湖北部不同区域风浪平均波高的计算应选用不同计算模式,但是可用如下形式表示:其中,a1-a8为和地形及水生植物覆盖度等相关的参数.误差分析结果显示:离岸距离大于1km区域的参数a1-a8的取值分别为0.217456、1、0.15、0.6、0.09、0.6、1.0、0.0052,模式估算平均波高的误差小于24%;近岸区参数a7大于1,a8取0,a4取值介于0.6-0.72,a5介于0.00131-0.00168,模式估算平均波高的误差较大,表明近岸区波浪还需进行进一步的观测研究. 相似文献
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2003年6—7月梅雨期间,于太湖北部测定大气降雨、典型林冠穿透雨和地表径流水等样品的pH和N、P等营养元素化合物离子浓度,结果表明,林冠层穿透水pH平均值比大气自然降水高约1.2个pH单位,其中和酸性物质效率为82%-97%,中和能力显示出阔叶树大于阔、针叶混交树,阔、针叶混交树大于针叶树的规律,并计算比较了乔木冠层和草坪、村镇地表径流水相对于自然降水中的TN、TP比值.从而得出,树木冠层穿透水中的离子浓度的变化是对酸沉降的一种积极的响应. 相似文献
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基于实测和数值模拟方法分析了台风“摩羯”和“温比亚”过境巢湖流域时的影响.台风“摩羯”和“温比亚”过境时,在巢湖产生较大的风速和风浪过程,其中对东巢湖的影响最大,中巢湖次之,西巢湖最小.东巢湖、中巢湖、西巢湖在台风“摩羯”过境时出现了0.68、0.67和0.48 m的最大有效波高和2.25、2.33和1.95 s的最大平均波周期;而台风“温比亚”过境时则最大有效波高可达1.50、1.47和1.18 m,最大平均波周期可达2.99、3.04和2.74 s.影响较大的区域位于东巢湖与中巢湖连接的湖心水域,总体对东巢湖的影响最为显著,中巢湖次之,西巢湖最小.不同湖区湖心水域由于水深、风区长度大,往往是出现最大风浪强度的区域. 相似文献
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采用Y型沉积物再悬浮发生装置模拟3种风速条件下典型入湖河流河口沉积物再悬浮和沉降过程.结果表明,随着风速的增大,水柱中悬浮物总量增加;3种风速条件下氨氮(NH4+-N)增量均为负;小风和中风过程,正磷酸盐(PO43--P)总量呈减小趋势,大风过程,正磷酸盐总量出现了明显上升,相对于初始值增加了46%,在5.1~8.7m/s的某一模拟风速条件下PO43--P的释放和吸附达到动态平衡,其表观值与初始值相等.总氮(TN)和总磷(TP)总量随着风速的增加而增大,TN最大增量是初始总量的2倍,而TP则是17倍;风浪过后TN、TP总量基本恢复到初始值.典型风速过程中,营养盐垂向分布无明显规律. 相似文献
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A model on a physico-biological engineering experiment for purifying water in Wulihu Bay of Lake Taihu by using Trapa natans var. bispinosa was constructed. The state variables in water in the physico-biological engineering were ammonium nitrogen (NH4+-N); nitrate nitrogen (NO3--N); nitrite nitrogen (NO2--N); phosphate phosphorus (PO43--P); dissolved oxygen (DO); nitrogen (N) and phosphorus (P) in detritus; biomass density, N and P in phytoplankton and in Trapa natans var. bispinosa, N and P in the substance adsorbed by the membrane of the engineering and the rootstocks of Trapa natans var. bispinosa. The state variables in bottom mud layer were PO43--P in the core water,exchangeable P and N. The external forcing functions were solar radiation, water temperature, NH4+-N; NO3--N; NO2--N; PO43--P; N and P in detritus; DO; phytoplankton concentrations in inflow water and the retention time of the water in physico-biological engineering channel. The main physical, chemical and biological processes considered in the model were:growth of Trapa natans var. bispinosa and phytoplankton; oxidation of NH4+-N and NO2--N, of detritus break down; N and P sorption by the enclosure cloth of the experimental engineering and by the rootstocks of Trapa natans var. bispinosa in water; reaeration of water; uptake of P, NH4+-N, NO3--N by phytoplankton and Trapa natans var. bispinosa:mortality of the phytoplankton and Trapa natans var. bispinosa:settling of detritus; and nutrient release from sediment. Comparison of calculated results and observed results showed that the model was constructed reasonably for the experiment. The mechanism of purifying lake water in the experiment engineering was discussed by the use of the model. 相似文献
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In order to estimate the present-day pollution levels in the ecosystem of the Selenga River Delta and to monitor the changes caused by the discharge of household refuse and industrial wastes,as well as the functioning of the agricultural and stock farming,a comprehensive study of the water and bottom sediments in the main branches of the Selenga River Delta was carried out.This study has determined the concentrations of heavy metals in river water and bottom sediments in its delta. 相似文献