密云水库人工水源保护林降水再分配特征研究

对密云水库北京集水区3种类型人工水源保护林降水再分配特征研究，结果表明，在研究的2年间，大气降水总量545mm，刺槐林穿透降水量为437.78mm，林冠截留量97.73mm，树干茎流量12.49min，油松林穿透降水量397.98mm，林冠截留量131.54mm，树干茎流量15.48mm，板栗要穿透降水量422.07mm，林冠截留量110.73mm，树干茎流量12.20mm，次降雨条件下，林内穿透降雨量与产供销降雨量之间呈线性相关，且呈极显著水平，林冠截留量与次降雨量之间呈指数正相关关系，亦呈极显著水平。     

关于森林对降水截留过程的研究

本文主要对降水过程中的冠层截留、树干茎流、灌木草本截留、林下凋落物截留、土壤涵蓄、林地蒸散进行了系统阐述,呈现了森林对降水整个截留的整个过程。     

森林对水文要素的影响

本文利用径流实验站森林观测场资料,通过综合研究,阐明森林对降水的截留量、树干流下量的影响因素及其计算的理论和经验公式.利用水文基本站网的资料,论证了森林对洪水、枯水、年径流、年降水及水质的不同影响.认为有必要确切地估计森林的作用.需要根据具体情况,科学地评价森林对水文要素的影响.有时森林削减洪峰,有时森林会增加洪峰;有的地区森林增加径流,有的地区森林减少径流;森林在流域内的分布位置差异也会产生不同的影响.所以应全面地、客观地估计森林的作用.     

北京典型村镇降雨径流污染及排放特征

以2009～2010年在北京郊区大牛坊村和榆林村的10场降雨地表径流中污染物监测数据为基础,分析了村镇降雨径流污染物排放特征及初期冲刷效应.结果表明,地表径流中CODCr和SS为主要污染物;雨污合流制村镇地表径流中,TP、TN、CODCr与SS的事件平均浓度(EMC)均值分别为0.11mg/L、3.09mg/L、1 684.27mg/L、285.83mg/L.雨污分流制村镇地表径流中,TP、TN、CODCr与SS的EMC均值分别为0.37mg/L、4.73mg/L、281.97mg/L、72.57mg/L.降雨径流污染物具有较明显的初期冲刷效应,40％～50％的TP、TN、CODCr与SS污染负荷由占总径流量30％的初期径流所运移.     

粉煤灰淋溶特性试验研究

通过淋溶试验来模拟大气降水对粉煤灰的淋溶过程以及淋溶液对土壤和浅层地下水水质的影响,从模拟试验结果可知:经过一段时间的物化作用后,土壤中会蓄积部分污染物质,土壤对(氟)F-、(砷)As等污染物的吸附量较大,地下水污染不可避免。     

酸雨的成因与危害

酸雨是指PH值低于5.6.的降水。广义的酸雨掼酸性物质以湿沉降或干沉降的形式从大气转移到地面上。湿沉降是指酸性物质以雨、雪形式降落到地面,干沉降是指酸性颗粒物以重力沉降、微粒碰撞和气体吸附等形式由大气转移到地面。 酸雨的形成机制复杂,它是大气污染物与空气中水和氧之间化学反应的产物,是一种复杂的化学和物理过     

城市雨水处理工艺与技术

城市化的快速发展使不透水地面面积迅速增长,雨水径流量也随之增加,由于降水淋洗大气污染物及其对地表污染物的冲刷,其污染威胁不能再被忽视.雨水径流有明显的初期冲刷作用,污染物集中在初期的数毫米雨量中,因此,控制初期雨水成为雨水利用系统和城市径流污染控制的一项主要举措.初雨弃流装置主要有优先流法弃流池、切换式或小管弃流井、旋流分离式初雨弃流设备、自动翻板式初雨分离器等多种型式.弃除初雨的径流建议采用物化方法进行处理,宜采用筛网格栅、混凝沉淀及过滤等工艺.     

辽宁东部山区日本落叶松人工林对水质的影响

为了解辽宁省东部山区日本落叶松人工林对水质的影响,试验用多参数水质监测仪和原子吸收法对大气降水、穿透水、树干径流和地表径流中的pH值、溶解氧、浊度、电导率、氧化还原电位、K、Na、ca、Mg和Fe等水质指标进行测定。     

森林植被对库区水质净化作用问题的研究

通过对山东省黄前库区流域森林主要类型刺槐林和油松林对降水分配的研究，分析测定了酸性降水条件下，不同森林类型土壤pH值的变化及其林下地表水和土壤渗透水中各种微量元素含量的变化。研究结果表明：地上部分对降水的吸持刺槐林明显大于油松林；刺槐林对水质的净化作用大于油松林．这一研究可为山区集水区建立水源涵养林的树种选择提供参考．     

气候对森林-径流关系的影响

为了揭示气候对森林-径流关系的影响,利用已有的不同地区森林集水区试验结果分析森林-径流关系空间变化规律,然后在生物物理/动态植被模型SSi B4/TRIFFID与TOPMODEL的耦合模型对长江上游梭磨河流域不同温度下植被演替及蒸发与径流的动态变化过程的模拟结果基础上,通过分析水热条件对净光合速率、冠层湿润分数、蒸腾、冠层截留蒸发以及土壤蒸发的影响,分析水热条件对森林-径流关系的影响。主要结论有:水热条件通过控制森林的净光合速率、蒸腾、冠层截留蒸发和土壤蒸发影响森林-径流关系;随着温度增加,森林蒸散发增加幅度大于其它植被类型和裸地,使森林-径流关系发生变化,水热条件的空间变化决定了森林-径流关系和水分利用效率的空间变化;受气候垂直地带性和水平地带性影响,随着海拔高度下降或从北到南随着温度增加,水分利用效率减小,森林-径流关系存在从增加径流量到对径流量没有明显影响再到减小径流量的变化,水分胁迫或高温将抑制森林蒸腾从而减小森林对径流量减少的作用,森林集水区比较试验结果体现了森林-径流关系这种空间变化规律。     

周村水库大气湿沉降氮磷及溶解性有机物特征

为揭示周村水库大气湿沉降中污染物的污染特征,通过收集周村水库2016年3月至2017年2月大气湿沉降样品,测定了大气湿沉降中氮磷以及溶解性有机物的质量浓度,分析了污染物的污染特征及大气湿沉降量的变化规律。结果表明:周村水库的降水主要集中在夏秋季,占全年的68.50%;降水中总氮质量浓度在1.67~7.63 mg/L之间,氨氮和硝氮是其主要组分,分别占总氮的52.91%和28.49%;降水中的硝氮和氨氮年湿沉降通量分别为772.45mg/m^2和1411.99 mg/m^2,且与降水量呈显著正相关关系(P<0.01);单因子水质评价法和综合污染指数法评价得出大气湿沉降中的降水大多为劣Ⅴ类的重度污染水体;总磷和有机物的湿沉降通量最大值出现在夏季,与降水量也呈显著正相关关系(P<0.01);大气湿沉降中的溶解性有机物以富里酸为主,呈现较强的自生源特征。     

浙江省大气降水水质对地表水水质的影响

对浙江省92个降水水质监测点采集的118个降水水样进行实验室检测,结合江河地表水水质同步监测资料,研究大气降水的主要污染物以及降水水质对地表水水质的影响。结果表明：降水中的pH值为5.86,TN、NH3-N、TP平均质量浓度分别达到1.54 mg/L、0.83 mg/L和0.035 mg/L,降水水质与监测点附近地表水水质未见明显相关关系,但降水中的NH3-N、TN和TP与地表水相同指标质量浓度的比率分别达到了60%、55%和22%,可见大气降水对地表水水质的影响不容忽视。     

Investigation of heavy metals transportation from soil to the pine tree.

The Scots pine (Pinus sylvestris L.) is the most common tree in Lithuanian forests. Research on the impact of pollutants on pines allows us to evaluate pollutants in a major part of Lithuanian forests. Heavy metals (HMs) are among the major pollutants entering forest ecosystems in different ways: in their wet and dry form they come from local or distant sources of emission by being transported from seas alongside with nutrients and sea salt, washed up from the dead plants accumulated in soil, and together with mineral particles brought by wind or water. During the period of investigation, a decrease in the Cr concentration in pine rings is seen. High Zn concentrations (in 1987--1989 Zn concentration was 27.6 mg x kg(-1)) in the pine may be caused by emissions from heavy traffic. The results have shown that Mn has the highest concentration as compared with that of other HMs in the soil around the pine (at the depth of 30-40 cm, Mn concentration is 780 mg x kg(-1)). In comparison with other HMs, Cu and Zn have the largest factor of transport from the soil to the wood (0.39 and 0.49 respectively).     

Budgets of major ionic species and nutrients on a dam reservoir in forested watershed.

To evaluate the role of a dam reservoir in the runoff of pollutant loadings from a forested watershed, the input-output budgets in the Ikuno dam reservoir had been investigated for eight years since 1996. The T-N, T-P, TOC and major ionic species in the bulk precipitation, stream water, and outflow were measured. The residence time calculated by using the data of the inflow and outflow was 0.3 year. The average precipitation was 1,772 mm during the investigation period (1996-2004). The direct deposition to water surface was less than one percentage to total loadings of nutrients and major ionic species. The ratios of output to input of TOC, TN, and TP were 1.04 to 1.42, and those of major ionic species were from 0.83 to 0.99 except for NO3(-), which was 1.12. However, the ratios of output to input of major ionic species except for NO3(-) at the Ikuno dam reservoir will be larger, and those of NO3(-), TOC, TN, and TP will be smaller, if we also include rain events. These results suggested that the dam reservoir played a role as a sink for pollutants in forested watershed, and that the pollutant loadings to downstream may decrease.     

于桥水库沉积物内源污染特性研究

通过对天津市于桥水库沉积物中污染物的释放实验研究,找出了于桥水库底泥中磷、有机质、氮、铁、锰等污染物释放的影响因素,得出了溶解氧、pH值、水温等影响因素对底泥污染物释放的影响程度,并对各污染物的释放机理进行了探讨。磷的释放条件:pH值≥8时,好氧条件下会缓慢释放,当ρ(DO)<2 mg/L时快速释放;在中酸性条件下,当ρ(DO)<1 mg/L时发生较快速释放;低溶解氧和高pH值协同作用强烈。有机物和氮的释放主要受溶解氧浓度影响,与pH值关系不大,在ρ(DO)<2 mg/L时发生了快速释放。溶解性铁、锰的释放取决于水体pH值,在酸性条件下,ρ(DO)<1 mg/L时释放。     

云南石林典型植被类型的降水垂直分配及水平汇聚规律观测研究

变化环境下的水资源管理及植被恢复是岩溶区亟待解决的现实问题。以云南石林岩溶区典型植被类型为对象,设置实验样地并开展了2018-2019年两个雨季的野外观测,分别对不同植被类型的降雨分配及汇聚规律进行了探索。结果表明:石林地区受到亚洲季风的控制,降水量的年内变化具有显著的季风区特征,即高度集中于湿季,特别是5-8月,降雨类型以小雨和中雨占主导,两者在全年降水场次中的比例分别为70%、15%;各实验观测植被类型的穿透雨量、树干径流量以及截留量均随着林外降雨量的增加而增大,降雨量的分配特征为降雨量>穿透雨量>截留量>树干径流量;各植被类型的径流系数差别明显,变化范围为0.01%~0.36%,石漠化裸地区径流系数最大而坡耕地最小,但整体来看都非常小;产流的降雨量阈值差别较大,其范围为2.0~6.4 mm,随着林外降雨量的增多,各观测样地的地表产流量也呈现增大的态势。本观测研究结果可以为岩溶区水资源管理与生态环境恢复保育提供科学依据。     

中和水解酸化生物接触氧化混凝气浮吸附处理山梨酸生产废水

针对山梨酸生产废水中主要污染物的理化性质和山梨酸对微生物具有抑制作用的特点,首先进行石灰中和-沉淀处理,使部分污染物转为沉淀物得以去除,并将废水的pH值提高到7~8,减弱生化处理阶段山梨酸对微生物的抑制作用。在生化阶段,采用水解酸化-好氧工艺,利用厌气菌和乳酸菌分解废水中残留的山梨酸,同时兼性细菌(水解菌和产酸菌)可将废水中的大分子有机物分解为易生化的小分子有机物,BOD5与COD之比值从0.19提高到0.30,改善了废水的可生化性,为后续好氧处理创造条件,提高生化处理的整体效果。实际工程运行效果表明:中和-水解酸化-好氧-混凝气浮-吸附工艺可将废水的ρ(COD)从15 000 mg/L降至100 mg/L以下,主要污染指标均达到国家排放标准。     

Effect of nickel ions on anaerobic methane production from water hyacinth

The effect of different concentrations of nickel ions (Ni(2+), 0, 10, 40 and 80 mg/L) on the anaerobic methane production of water hyacinth were investigated. Under these four concentrations, the methane production in 40 d was 2,275, 2,703, 3,210 and 2,481 mL, respectively. This situation illustrated that the Ni(2+) promoted the growth of hydrogen-producing acetic acid bacteria and methanogenic bacteria, even at high concentrations (i.e. 40-80 mg/L). The highest methane production per unit weight water hyacinth reached 206 mL/gTS with 40 mg/L Ni(2+). Meanwhile, the modified Gompertz and Logistic equations were applied to describe the effect on anaerobic culture of Ni(2+). According to these models, the values of methane production potential (mL) for four concentrations were in the following order: 40 mg/L (3,123.42 ± 60.08) > 10 mg/L (2,541.16 ± 46.94) > 80 mg/L (2,432.36 ± 40.18) > 0 mg/L (2,238.10 ± 31.90). According to the analysis of the digestate, the residual concentration of Ni(2+) was approximately 1.05-4.9 mg/L, which was relatively low compared with the Ni(2+) concentrations in the raw feedstock. The results would provide academic guidance and technical support for treatment of water hyacinth with an accumulation of heavy metals.     

Determination of minimum flood flow for regeneration of floodplain forest from inundated forest width-stage curve

Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions.However,river flows,and especially flood flows,have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation,resulting in severe deterioration of floodplain ecosystems.Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest's restoration or protection.To balance water use for economic purposes and floodplain forest protection,the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve.The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve,and is determined directly or analytically from the curve.For the analytical approach,the problem under consideration is described by a multi-objective optimization model,which can be solved by the ideal point method.Then,the flood flow at the minimum flood stage(minimum flood flow),which is useful for flow regulation,can be calculated from the stage-discharge curve.In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream,the proposed method was used to determine the minimum flood stage and flow for the forest.Field survey of hydrology,topography,and forest distribution was carried out at typical cross sections in the floodplain.Based on the survey results,minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s.Their maximum,393 m3/s,was considered the minimum flood flow for the study river reach.This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.     

Influence of pH on short-cut denitrifying phosphorus removal

Through a series of experiments using denitrifying phosphorus-accumulating sludge in sequencing batch reactors(SBRs), the variations of the intracellular polymers during the anaerobic phosphorus release process at different pH values were compared, the probable reasons for different performances of phosphorus removal were examined, and system operations in a typical cycle were investigated. The results show that the phosphorus removal rate was positively correlated with pH values in a range of 6.5-8.5. When the pH value was 8.0, the anaerobic phosphorus release rate and anoxic phosphorus uptake rate of the activated sludge were 20.95 mg/(g?h) and 23.29 mg/(g?h), respectively; the mass fraction of poly-b-hydroxybutyrate(PHB) increased to 62.87 mg/g under anaerobic conditions; the mass fraction of polyphosphate was 92.67 mg/g under anoxic conditions; and the effluent concentration of total phosphorus(TP) was 1.47 mg/L. With the increase of pH, the mass fraction of acetic acid and PHB also increased, and the absorption rate of acetic acid was equal to the disintegration rate of polyphosphate. When the pH value was above 8.0, biological phosphorus removal was achieved by chemical phosphorus precipitation, and the phosphorus removal rate decreased.