总磷过硫酸钾—钼锑抗光度法的过滤影响

采用过硫酸钾－钼锑抗法测定太湖水样中的总磷，以高压釜消解法为佳，过滤问题影响不大，若采用常压消解法，则应注意使消解后的溶液保持１０亳升，消解后的样品先过滤后调ｐＨ为宜。     

过硫酸钾消化-紫外分光光度法测定水中总氮的改进

为简化消解过程，使温度易于控制，提高总氮测定方法的稳定性，采用烘箱代替高压锅进行消解，过硫酸钾氧化，紫外光度法测定样品中的总氮，经实验研究对比，该法稳定性好，易于操作，且能得到令人满意的结果。     

水质总氮测定中的有关问题探讨

对总氮测定中的一系列影响因素，诸如实验用水，器皿的洗涤，实验室环境试剂的提纯、配制和保存，消解温度、压力和时间的控制，以及高氨氮水样中的总氮测定、总氮、总磷的同时测定和其他有关的问题，作了较为详细的探讨，并提出了相应的解决办法。     

烘箱法测定地表水中的总氮

以烘箱代替高压锅进行消解,采用过硫酸钾氧化-紫外分光光度法测定地表水中的总氮.经实验研究对比,该法可简化消解过程,使温度易于控制,提高了总氮测定方法的稳定性,且易于操作,灵敏度、准确度、精密度、检出限等均令人满意.     

水中总磷测量的不确定度评定

采用钼酸铵分光光度法测定水中总磷的含量，分析该法测量不确定度的来源，评定水中总磷的测量不确定度。     

钼锑抗分光光度法测定总磷问题的讨论

钼锑抗分光光度法测定总磷，方法相对成熟，但是实验过程中干扰因素多，因此需通过大量的对比实验，来探讨测定水中总磷的最佳条件。     

生活污水二级生物处理后的铁盐混凝除磷试验研究

以生活污水二级生物处理后的出水为研究对象，考察了铁盐对浓度在2－4mg/L范围内的总磷的混凝去除效果及影响因素。结果表明，铁盐除磷的最佳pH为7.5-8；铁盐投加量较低时，适当提高GT值可使总磷去除率增加15％－20％；在适当的混凝搅拌条件下，三阶铁盐和聚合硫酸铁对总磷的去除率均在70％以上，混凝后过滤可使出水中总磷降至0.5mg/L以下。     

高压溶样法在土壤和沉积物消解中的应用

本文介绍了高压溶样在土壤及沉积物消解中的应用。将试样置于聚四氟乙烯高压溶样罐中,加入消解波,密闭容器,在160℃加热4小时。冷却后将消解液在电热板上蒸至近于,用0.5％HNO_3定容待测。比较了硝酸—高氯酸—氢氟酸、硝酸—高氯酸、硝酸和王水—高氯酸四种消解液的高压溶样效果,以硝酸—高氯酸—氢氟酸消解为最佳。用该法消解、原子吸收法测定了土壤和沉积物参考样的Cr、Cu、Mn、Ni、Ph和Zn结果与参考值符合很好,平均标准偏差小于5％。高压溶样消解土壤及沉积物试样,分解效率高,环境污染小,是一种比较理想的消解方法。     

基于SWAT模型的大宁河流域污染物负荷分布特性分析

为了给流域污染物总量控制及分配工作提供理论依据，利用SWAT模型分析了大宁河巫溪水文站控制流域污染物负荷分布特性，结果表明：耕地是泥沙和总磷污染的主要来源，泥沙和总磷负荷分别占整个流域的95%和50%以上；后溪河流域是整个流域内污染负荷最高的支流流域，泥沙贡献率为46.02%，总磷负荷贡献率为60.15%；流域西南部的土壤侵蚀现象较为严重，尤其是子流域17和20；东溪河内子流域7是总磷负荷较高的地区，应重点进行控制。     

中国主要湖泊叶绿素与总磷关系

根据中国５０个主要湖泊叶绿素与总磷调查资料，统计计算结果表明湖泊水体中叶绿素与总磷具有显著相关性。     

Effects of suburban land use on phosphorus fractions and speciation in the Upper Peruque Creek, Eastern Missouri

This field study was conducted to explore the spatial and seasonal changes in total phosphorus and fraction distribution in relation to land uses. Water samples were collected biweekly at four sampling locations, which represented different potential phosphorus sources along the Upper Peruque Creek in Eastern Missouri. Total phosphorus concentrations of > 0.8 mg/L appeared sporadically at site 2, downstream of a small community, with an average of 0.82 +/- 0.14 mg/L in fall. Particulate phosphorus accounted for approximately 80% of total phosphorus at all sampling sites, except for site 2, where approximately 50 to 75% of dissolved phosphorus was often observed. Approximately 71 and 85% of total phosphorus in the sediment was in the form of iron (III) phosphate at the headwaters and downstream sites, respectively; 29 and 15% was in the form of phytic acid at the two sites. Land uses affect the total phosphorus concentration and alternate phosphorus fraction and speciation in the creek.     

Phosphorus use-efficiency of agriculture and food system in the US

The rapid increase in human mobilization of phosphorus has raised concerns on both its supply security and its impact on the environment. Increasing the efficiency of phosphorus use is an approach to mitigate the adverse impacts associated with phosphorus consumption. This study estimates the life-cycle phosphorus use-efficiency of the US food system. A framework for accounting phosphorus stocks and flows is developed, and the account was populated with data. A map of phosphorus stocks and flows around the US food system is drawn and phosphorus use-efficiency was calculated. The results show that only 15% of the total phosphorus extracted from nature for the provision of food is eventually ingested by humans and the rest is lost to the environment. Major losses occur during the livestock, meat and dairy production and crop cultivation stage, where about 66% of the total phosphorus extracted is lost to the environment. The results also show that other losses of phosphorus including household food waste, mining waste, and fertilizer manufacturing waste are not negligible, which constitute about 19% of the total phosphorus extracted for food purpose. A data quality assessment and sensitivity analysis was performed to identify data quality hotspots and to envisage effective measures to improving phosphorus use-efficiency. Improving yields of livestock and crop cultivation without additional phosphorus input and reducing household food waste are shown to be effective measures to improve life-cycle phosphorus use-efficiency. The results highlight the need of a concerted effort by all entities along the life-cycle for efficient use of phosphorus.     

Evaluation of phosphorus bioavailability in sediments of three contrasting lakes in China and the UK

The bioavailability of phosphorus (P) in sediments from West Lake and Lake Tai (China) and Lough Erne (Northern Ireland) was evaluated using total P (TP), water soluble P (WSP), readily desorbable P (RDP), algal available P (AAP) and Olsen-P. The results indicated that the TP content, the amounts of phosphorus extracted by each method and their proportions to TP varied widely between sediments of the three lakes. TP and chemical extractable phosphorus in the sediments of Lough Erne were considerably higher than those of the two lakes in China. Although TP in the West Lake sediments was similar to that of Lake Tai, the extractable phosphorus data suggested that the bioavailability of P in West Lake sediments was higher than that in sediments from Lake Tai. Nevertheless, the rank order of extraction efficiency was the same in all lakes and the amount extracted was in the sequence AAP > Olsen-P > WSP > RDP. There was a good correlation between extracted and TP in all the methods examined.     

Measurement of organic nitrogen and phosphorus fractions at very low concentrations in wastewater effluents

The purpose of this study was to develop simple, accurate, and inexpensive measurement protocols for dissolved organic nitrogen (DON) and dissolved non-reactive phosphorus (DNRP) at low levels in wastewater effluents. Two protocols are presented--one to measure DON exclusively, and the other to measure DON and DNRP simultaneously. Currently, DON and DNRP are calculated indirectly by subtracting the dissolved inorganic fractions from the total dissolved concentration, resulting in significant errors. To increase the accuracy of DON measurements, effluent sample pretreatment using ion exchange to remove nitrate was applied. Spectrometric methods were selected to measure the inorganic fractions-the second derivative UV spectroscopy method for nitrate, and the malachite green method for orthophosphate. These methods, combined with the optimized persulfate digestion of the samples, can be used to measure total dissolved nitrogen and phosphorus accurately. The measurement ranges attained were 0.05 to 3 mg N/L for DON and 0.01 to 0.5 mg P/L for DNRP.     

巢湖合肥地区洗衣粉排磷占入湖磷贡献率的研究

合肥地区人均洗衣粉用量为3．12kg/a,洗衣粉总用量为8345t/a,洗衣粉带入水体的总磷量为256．08t/a,占入湖总磷负荷量的13．62％。因此,实行“禁磷”措施后,可削减该地区入湖总磷负荷量的13．62％,对改善巢湖水质将会起到一定的积极作用。     

水生植物总氮测定中两种消化方法的比较

水生植物在人工湿地污水净化过程中起着非常重要的作用,植物组织中氮、磷的含量是考察人工湿地净化污水效能的一个重要指标。采用经典的Kjeldahl（凯氏）消化法和H2SO4—H2O2消化法测定了人工湿地植物体中总氮含量,分析了两种消化方法各自的优缺点,并应用SPSS统计软件对两种方法测得的数据进行统计检验。其结果表明,两种方法测得的总氮含量具有显著性差异。应根据不同的实验要求选择适宜的测定方法。     

Dynamics of phosphorus forms in the bottom sediments and their interstitial water for the Prut River (Moldova)

Phosphorus concentration in rivers results from both external inputs and internal loading from the bottom sediments. Seasonal, spatial, and multi-annual dynamics of phosphorus forms in bottom sediments and their interstitial water for the river Prut (Moldova) were evaluated. In order to determine content of total phosphorus in the bottom sediments, fresh (wet) samples were subjected to persulfate oxidation. The content of inorganic phosphorus was determined after acidic oxidation of samples. The amount of organic phosphorus was obtained by subtracting inorganic phosphorus from the amount of total phosphorus. Content of phosphorus forms in interstitial water was determined after centrifugation of fresh (wet) sediments. In general, the shape of dynamics of the amounts of inorganic phosphorus in sediments was close during years?2009, 2010, and 2011, with registered higher contents of this form on the middle course of the river. The spatial dynamics of organic phosphorus is less homogeneous along the Prut River. During 2009, higher amounts of organic phosphorus were recorded on the middle sector. During the spring of year?2010, the content of organic phosphorus in sediments was practically not changed along the river. The ratio of inorganic/organic phosphorus in bottom sediments was similar during the researched years, with the predominance of the inorganic phosphorus being recorded. Also, the increasing tendency of the percentage of organic phosphorus from spring to summer was identified. Generally, appropriate spatial and seasonal dynamics of phosphorus forms in bottom sediments and their interstitial water were recorded, although sometimes with some differences.     

三垟湿地沉积物-间隙水-上覆水界面磷形态研究

沉积物与上覆水间营养物质交换,成为导致水体发生富营养化的首要化学变迁过程.分别在三垟湿地的柑橘林(S1)、景观用地(S2)和生活用地(S3)取样,研究了沉积物-间隙水-上覆水界面磷形态以及相互关系.结果表明:(1)沉积物TP增加时,间隙水PO3-4和可溶性总磷(TDP)也增加.要削减磷在上覆水中的含量,控制间隙水PO3-4或TDP是一良策.(2)随着沉积物铁磷、铝磷的增加,间隙水PO3-4也增加.在三垟湿地沉积物中,铁磷和铝磷含量都可作为间隙水PO34-含量的指示.(3)S1、S2和S3的沉积物活性磷、间隙水TDP和上覆水TDP存在明显的浓度梯度,沉积物活性磷＞间隙水TDP＞上覆水TDP.说明在三垟湿地中,沉积物活性磷是磷释放的关键因子,而沉积物-间隙水界面则是磷释放的关键界面.     

红枫湖底泥磷负荷释放

为了研究高原湖泊底泥沉积物中磷的释放负荷,对贵州红枫湖区10个地区的沉积物进行了磷形态分析。选取10个采样点中5个典型区域,研究结果表明,底泥中各形态磷占总磷比例Org-P为58.6%,NaOH-P为29.91%,Ca-P为11.48%,底泥中主要的磷形态为有机磷。上覆水溶解性总磷酸盐(TSP)与底泥中各形态磷的相关性研究表明,底泥中的Ca-P与上覆水中的TSP几乎没有相关性,NaOH-P与Org-P与上覆水的TSP有较高的相关性(R2>0.94),而底泥中的总磷(TP)与上覆水中的TSP相关性最高(R2>0.98),底泥中这种形态的结构有利于抑制底泥的释放。研究表明,在10点位样品中,间隙水中TP和SRP(溶解性正磷酸)浓度远大于上覆水体中相应磷形态的浓度,间隙水中TP平均浓度为0.37 mg/L,SRP平均浓度为0.18 mg/L,上覆水体中TP平均浓度为0.10 mg/L,SRP平均浓度为0.02 mg/L,间隙水中TP、SRP与上覆水中TP、SRP存在了一种浓度梯度。     

滇池湖湾大水域种养水葫芦对水质的影响分析

为了探讨大水域种养水葫芦对滇池湖湾水质的影响,于2010年8—10月对滇池白山湾约70 hm2水葫芦种养区域的水质特征进行动态监测。结果表明,水葫芦区水体中总磷、总氮及高锰酸钾指数从9月中旬后开始逐步上升。水葫芦区水体溶解氧、pH较近水葫芦区和远水葫芦区显著降低,但水葫芦区溶解氧仍维持在较高水平;总磷、总氮及高锰酸钾指数较近水葫芦区和远水葫芦区显著升高;在水葫芦周围水体（近水葫芦区）水质得到明显改善,表现为水体透明度显著高于水葫芦区及远水葫芦区,总磷、正磷酸盐、总氮及叶绿素a明显低于水葫芦区及远水葫芦区。