太湖梅梁湾不同形态磷周年变化规律及藻类响应研究

以太湖梅梁湾为研究对象,2013年对水体中不同形态磷和藻类进行了逐月观测,探讨了风浪扰动和藻类生长双重影响条件下不同形态磷间转化规律以及藻类生长和不同形态磷含量间的内在联系.结果表明,梅梁湾水体中总磷(TP)、颗粒态磷(PP)、溶解性总磷(DTP)、溶解性磷酸盐(DIP)和生物有效磷(BAP)均呈现出"夏秋高"、"冬春低"的周年变化规律,藻类生长也呈现了类似规律,而溶解性有机磷(DOP)和可被生物利用颗粒态磷(BAPP)的变化规律并不规则.颗粒态磷生物有效性(BAPP/PP)在6~10月期间仅为12.75%,显著低于年度平均值37.14%.这可归因于沉积物频繁扰动下内源磷固定效应以及藻类生物吸收作用加快了颗粒态磷向溶解态磷的转化.在此期间,DTP占BAP的质量分数高达69.33%(平均值),明显高于BAPP(30.67%,平均值),也高于DTP的周年平均值(56.63%),其也是藻类生长旺盛季节.     

底泥扰动下藻类对不同形态磷在水体中分布的影响

研究了反复扰动与藻类共存条件下,水体中溶解性磷、颗粒态磷、生物有效磷的分布规律,并分析了颗粒物质物理化学吸附与藻类生物利用对水体中磷消失的贡献率.结果表明,扰动抑制了水体中藻类生长,叶绿素a增加量仅为3.53μg/L(初始30μg/L)和4.80μg/L(初始120μg/L),而无扰动下该值分别为21.36μg/L (初始30μg/L)和14.49μg/L (初始120μg/L).并且,溶解氧水平和pH值均低于无扰动状态.扰动导致水体中总磷和颗粒态磷显著增加,但溶解性总磷(DTP)和溶解性磷酸盐(DIP)均有所降低.对于DTP而言,扰动状态下,颗粒物质吸附占90%,而无扰动下,则降低至60%,相应地,藻类生物利用则增加至40%.无论扰动与否,BAP基本处于稳定状态,而BAPP占BAP的百分比则有所增加.扰动状态下BAPP占PP的百分比明显低于无扰动状态.这暗示了扰动对水体中磷迁移和转化的作用大于藻.     

六叉河小流域不同景观结构中径流磷形态差异分析

选取巢湖六叉河小流域,研究了流域内不同类型景观降雨产流过程中径流磷素的形态差异.结果表明,旱地径流中总磷、溶解性总磷、颗粒态总磷、总活性磷、颗粒态活性磷的浓度最高,水稻田次之,河道中最低.颗粒态磷是旱地和水稻田磷索输出的主要形态,颗粒态活性磷占总活性磷的80%以上;而河道径流中各种磷形态浓度值均较低,总磷浓度均值在0.4mg·L-1以下,磷素输出以溶解态磷为主.磷素由旱地经过水稻田向河道传输过程中,颗粒物浓度显著下降,河流中颗粒态磷浓度降低至50%左右,活性组分浓度显著降低.由水塘、沟渠等组成的多水塘系统不仅降低了磷素输出的总量,而且对活性磷有较强的削减作用,在非点源流域控制及水源地水质保护方面有重要意义.     

沉积物悬浮频率对水体颗粒态磷生物有效性的影响

通过室内试验模拟沉积物在不同频率下的悬浮过程,研究了悬浮频率对颗粒态磷生物有效性的影响.结果表明,沉积物悬浮导致颗粒态磷的生物有效性显著降低,30d时,藻类可利用态磷（AAP）占悬浮物总磷（Tot-P）的百分比仅为初始状态（56.75%）时的26.24%（悬浮频率较小）和20.04%（悬浮频率较大）.内源磷形态分析表明...     

金盆水库沉积物磷的来源及分布特征

为探究分层型水源水库沉积物中磷的来源与分布特征,以西安金盆水库为对象,针对2017年3～11月金盆水库水体、沉降颗粒及沉积物柱状样品总磷(TP)含量及形态分布特征进行研究.结果表明,金盆水库主库区表层沉积物总磷含量及形态分布受水体颗粒磷(PP)沉降作用明显,相关系数r~2=0. 877 5;同时表层沉积物总磷含量还受到沉积物内部生物地球化学的共同作用. 6～8月金盆水库水体藻类剧烈繁殖演替,繁殖过程中大量失去活性、死亡的藻类不断向底部水体沉积,形成以藻类等颗粒磷为主导的内源污染,沉降颗粒总磷含量达(753. 51±17. 11) mg·kg~(-1),表层沉积物总磷含量随之增加,以铁铝结合态非活性磷(NaOH-nrP)为主; 9～11月进入汛期,径流水体携带大量泥沙等负荷较大的污染物汇入水库,使得水体颗粒磷浓度相应增大,然而由于单位质量泥沙中总磷含量占比较小,导致径流过程中表层沉积物总磷含量逐渐降低,泥沙径流过程中颗粒磷以无机态的钙磷(Ca-P)和残渣态磷(rest-P)为主,二者约占沉积物总磷(TP) 55. 8%～66. 2%,受颗粒沉降影响相对较大.活性磷(SRP)、铁锰螯合态磷(BD-P)和铁铝结合态活性磷(NaOH-srP)这3种形态磷较活跃,在环境条件的变化(主要是氧化还原条件)下发生一系列迁移转化,受沉积物内部生物地球生物化学过程作用明显.     

湖泊沉积物短时间反复扰动下悬浮物上生物有效磷的动态变化

以太湖梅梁湾、月亮湾的沉积物和上覆水为材料,研究了较短时间尺度和沉积物反复扰动条件下,悬浮物中不同形态生物有效磷数量分布的变化特征.结果表明,随着扰动次数的增加,上覆水中藻类可利用磷(AAP)占溶解态总磷(DTP)的百分比均有所降低.试验期间,悬浮物中弱吸附态磷(NH4Cl-P)、可被生物利用颗粒态磷(BAPP)占总磷(Tot-P)的百分比平均值分别增加了3.5%、37.3%(梅梁湾)和2.0%、50.7%(月亮湾).梅梁湾悬浮物上AAP含量及其占Tot-P的百分比随扰动次数增加而增加,月亮湾则恰好相反.扰动期间,悬浮物上BAPP含量始终大于NH4Cl-P和AAP之和,表明BAPP的80%是由NH4Cl-P和AAP组成的.这也暗示了,仅仅以悬浮物中NH4Cl-P、AAP来估算BAPP存在一定的不合理性.     

夏季滇池不同来源溶解性有机磷特征及其生物有效性

夏季选取了滇池不同来源(滇池湖体、入湖河流和大气降雨)水样,研究了其溶解性有机磷(DOP)含量及分布特征,并利用酶水解技术表征了其DOP生物有效性.结果表明,滇池湖体、入湖河流和大气降雨DOP浓度分别在0.001~0.117,0.002~1.722,0.006~0.112mg/L(平均0.027,0.197,0.037mg/L),分别占溶解性总磷(DTP)的18.3%~92.5%,4.2%~100%,25.4%~100%(平均55.3%,60%,58.9%),不同来源DTP均以DOP为主,入湖河流DOP浓度明显高于滇池湖体和大气降雨.不同来源DOP酶可水解磷(EHP)浓度分别为n.d.~0.058,n.d.~0.673,n.d.~0.031mg/L(平均0.017,0.064,0.010mg/L),分别占DOP的0%~127.5%,0%~105.6%,0%~55.6%(平均77.9%,38.7%,23.2%).不同来源DOP酶水解率(EHP/DOP)较高,滇池湖体DOP酶水解率明显高于入湖河流和大气降雨.不同来源DOP时空分布特征明显,且其生物有效性存在较大差异.其中,滇池湖体EHP以活性单酯磷和类植酸磷为主,入湖河流和大气降雨EHP以活性单酯磷为主,尤其是大气降雨二酯磷和类植酸磷含量较少,滇池湖体、入湖河流和大气降雨DOP生物有效性依次降低.不同来源DOP是与溶解性反应磷(SRP)同等规模的生物可利用磷源,二者共同维持了滇池富营养化.滇池治理要从全流域出发,考虑不同来源各形态磷对水质的影响.     

流溪河水库流域非点源溶解态氮磷污染负荷估算

流溪河水库作为广州市最重要的水源地之一,其水环境质量受到广泛关注. 利用基于SCS模型的污染负荷输出,对流溪河水库流域非点源溶解态氮磷污染负荷进行估算. 结果表明:流域非点源溶解态氮污染负荷为384.31 t/a,溶解态磷污染负荷为20.68 t/a.其中氮贡献最大的为林地,占50.93%;其次为园地,占18.10%.磷贡献最大的亦为林地,占49.22%;其次为旱地,占15.85%.溶解态氮单位面积污染负荷道路最高,为50.57 kg/(hm2·a);其次是水田,为33.60 kg/(hm2·a).而溶解态磷单位面积污染负荷最大是水田,为3.43 kg/(hm2·a);其次是道路,为3.19 kg/(hm2·a). 与水库流域颗粒态氮磷污染负荷比较表明,溶解态氮大于颗粒态氮,氮以溶解态迁移为主;溶解态磷则小于颗粒态磷,但由于颗粒态磷易随泥沙受阻或沉降,溶解态磷对水库水质的影响依然是总磷关注的重点.      

高岚河不同降雨径流类型磷素输出特征

通过对三峡水库次级支流高岚河流域不同强降水过程中水量、水质变化过程的同步监测,系统分析了产流过程中不同形态磷素浓度及通量变化的规律,解析场次降雨事件点源和非点源磷素入库负荷.结果表明,"矮胖型"降雨径流变化过程表现出迟滞性,而"尖瘦型"降雨径流为快涨快退;强降雨冲刷产生的泥沙携带大量颗粒态磷进入水体,使得总磷含量迅速增加,溶解性总磷和正磷酸磷浓度略微升高;相对于"矮胖型"降雨,"尖瘦型"强降雨产生的总磷浓度及通量极大值均高于"矮胖型"降雨,泥沙侵蚀效果更为明显;不同雨型下,磷通量与浓度随时间的变化过程和流量的变化过程具有大体一致性;各磷素在强降雨过程中流失非点源污染占90%左右,由于"矮胖型"降雨径流历时较长,非点源总磷负荷贡献率大于"尖瘦型".     

云南省境内怒江流域水质变化趋势分析

用线性回归方法对云南省境内怒江流域1980年～2000年的水质状况及污染物输送量进行长系列趋势分析.怒江流域污染物入河量呈上升趋势,河流总体水质有下降趋势,主要支流水质下降程度高于干流,并结合面源对河流水质贡献率大的特点,提出流域面源污染防治对策及建议.     

青春 责任 梦想 行动 2015年千名青年环境友好使者夏令营侧记

<正>"我们处在世界正在发生重大变革的时代,中国也正在实现着民族伟大复兴的关键时刻。青年人要承担什么责任?""我们应该团结更多的青年人,向全社会积极宣传环保理念,保护我们共同生存的家园。"一名青年使者刚刚回答完贾峰主任的问题,全场响起的是掌声——雷鸣般的掌声!8月17日,2015年"千名青年环境友好使者夏令营"在成都市温江区正式开营。环境保护部宣传教育中心主任贾峰亲临现场,并为青年学子们讲授了热情     

Asbeste Arten,Entstehung, Bedeutung,Problematik

Types of asbestos are distinguished not only by structure, chemical compositon, shape of aggregates, and length and quality of fibers, but also by its formation. Though consisting of quite common elements, deposits are formed only under very special conditions. Its unique combination of properties has created over 3000 fields of application (about 70% in asbestos cement). Great efforts have been made to substitute all types of asbestos by harmless, similarly cheap and versatile synthetic fibers, owing to the unquestioned carcinogenic properties of all asbestos dusts. However, development of such fibers has not made any remarkable progress until recently. Consequently risk to workers in mining and manufactoring, consumers, outsiders, and the environment should be kept as low as possible by intensifying precautions and diminishing emissions.     

Effect of CaO on retention of S, Cl, Br, As, Mn, V, Cr, Ni, Cu, Zn, W and Pb in bottom ashes from fluidized-bed coal combustion power station

This work was conducted to evaluate whether Ca-bearing additives used during coal combustion can also help with the retention of some other elements. This work was focused on the evaluation of bottom ashes collected during four full-scale combustion tests at an operating thermal fluidized-bed power station. Bottom ashes were preferred to fly ashes for the study to avoid interference from condensation processes usually occurring in the post-combustion zone. This work focused on the behaviors of S, Cl, Br, As, Mn, V, Cr, Ni, Cu,Zn, W, and Pb. Strong positive correlations with CaO content in bottom ashes were observed（for all four combustion tests） for S, As, Cl and Br（R = 0.917-0.999）. Strong inverse proportionality was calculated between the contents of Pb, Zn, Ni, Cr and Mn and CaO, so these elements showed association to materials other than Ca-bearing compounds（e.g., to aluminosilicates, organic matter, etc.）. Somewhat unclear behaviors were observed for W, Cu, and V. Their correlation coefficients were evaluated as statistically ＂not significant＂, i.e., these elements were not thought to be significantly associated with CaO. It was also discovered that major enrichment of CaO in the finest bottom ash fractions could be advantageously used for simple separation of elements strongly associated with these fractions, mainly S and As, but also Cl or Br. Removal of5% of the finest ash particles brings about a decrease in As concentration down to 77%-80% of its original bulk ash content, which can be conveniently used e.g., when high As content complicates further ash utilization.     

珊瑚钨锡矿硅质尾矿中Cd、As、Zn、F富集迁移及环境污染

硅质尾矿在释放中性矿山废水(NMD)时所伴生的多元素复合污染问题值得重视。本文以桂东北珊瑚矿尾矿作为研究对象,通过分析该尾矿的组构、元素富集及迁移特性,筛选出主要污染元素,并探讨尾矿胶结层对元素富集迁移的影响。结果表明:(1)该尾矿中Cd、As、Zn及F富集程度较高、可交换态含量(易迁移释放量)较大,是主要的污染元素,而Cu、Pb、Tl产生污染的可能性较小;(2)胶结层对重金属具有再富集作用,但其对可交换态Cd、As(Tl)再富集明显,而对可交换态Cu、Pb、Zn再富集则不明显。胶结层中次生伊利石、石膏等胶结物趋向于吸附富集活性可交换态Cd、As。这表明该尾矿可能迁移释放出含Cd、As浓度较高的NMD。研究表明,硅质尾矿风化释出NMD的同时,可能伴生Cd、As、Zn等重金属以及F的复合污染。     

Algorithmen,gehirne, computer

In order to say something substantial about the fundamental limits of machines (especially of computers) and of human calculations, we must explicate the concept of algorithm. Such an explication is provided by the Turing machine. Thus, problems have been discovered which cannot be solved algorithmically. For other problems there are problem-solving procedures, but no elegant algorithms. That men are fundamentally superior to machines has not been shown as yet.     

意大利的金枪鱼、箭鱼、鸬鹚以及家燕等体内的多氯萘、多氯联苯、多氯二苯-p-二恶英、多氯二苯并呋喃以及p,p''''-DDE

我们曾对从意大利收集的金枪鱼、箭鱼、普通鸬鹚以及家燕体内的p,p'-DDE、多氯联苯同类物(PCBs)、多氯二苯-p-二恶英(PCDDs)、多氯二苯并呋喃(PCDFs)以及多氯萘(PCNs)浓度进行过测量.     

The monitoring,Evaluation, reporting,verification, and certification of energy-efficiency projects

In this paper, we present an overview of guidelinesdeveloped for the monitoring, evaluation, reporting,verification, and certification (MERVC) ofenergy-efficiency projects for climate changemitigation. The monitoring and evaluation ofenergy-efficiency projects is needed to determine moreaccurately their impact on greenhouse gas (GHG)emissions and other attributes, and to ensure that theglobal climate is protected and that countryobligations are met. Reporting, verification andcertification will be needed for addressing therequirements of the Kyoto Protocol. While the cost ofmonitoring and evaluation of energy-efficiencyprojects is expected to be about 5–10% of a project'sbudget, the actual cost of monitoring and evaluationwill vary depending on many factors, including thelevel of precision required for measuring energy andGHG reductions, type of project, and amount of fundingavailable.