Nitrogen and phosphorus in the Ngongotaha Stream

This paper gives the data and methods used to calculate the nitrogen and phosphorus loads of the Ngongotaha Stream, near Rotorua, New Zealand. The variations in concentration with time and with flow rate are given in some detail, as examples of what may happen in other streams of the central volcanic plateau, and a novel way to define a flow‐concentration curve is described. Nitrate, ammonia, dissolved reactive phosphorus (DRP), total phosphorus (TP), and total Kjeldahl nitrogen (TKN) concentrations were measured, and mean concentrations in 1976 base flow were found to be 527, 25, 32, 48, and 162 mg m^‐3 respectively. Nitrate concentrations showed seasonal variations, and although changes occurred during floods, they were not correlated with flow rate. DRP concentrations showed little variation, except that they dropped at the peak of the largest floods. TP was strongly correlated with flow rate during floods, and TP loads could best be calculated by allowing for a curvilinear relationship between concentration and flow rate. The logarithms of the TP load carried by a flood and the peak flow rate of the flood were highly correlated (R = 0.984). The annual loads of nitrate, ammonia, DRP, TP, and TKN were estimated to be 34, 1.3, 2.9, 6.0, and 26 tonnes in 1976.     

Water quality of the Waiohewa Stream,Rotorua

The chemical quality of the Waiohewa stream, Rotorua, was assessed from the results of 2 longitudinal surveys in summer 1978–79. In particular, changes in nitrogen concentration were examined. The quantity of ammonia increased downstream from unmonitored geothermal inputs, but, after dilution and neutralisation by a larger inflow of freshwater, considerable proportions of ammonia were converted to nitrate. In the first survey ammonia concentrations decreased from 4.48 to 2.47 g m^‐3 and nitrate concentrations increased from 0.59 to 1.13 g ^‐3 in a 3‐km stretch of the stream. Mass flow calculations show that nitrification could account for at least 55% of the ammonia decrease, the rest probably being lost through assimilation or denitrification. Laboratory incubation experiments showed that nitrification occurred in the stream bed. The geothermal waters contained low concentrations of boron (1.1–4.0 g m^‐3), filterable mercury (0.1–0.8 mg m^‐3) and arsenic (10–14 mg m^‐3).     

柘林湾网箱鱼类养殖环境氮磷负何研究

通过建立模型估算了柘林湾网箱养殖因投饵所产生的环境氮磷总负荷及不同来源、形式的氮磷负荷组成.结果显示,2006年柘林湾网箱养殖因投喂冰鲜鱼饵料产生的氮负荷为2760.39t、磷负荷为679.11t,其中残饵氮1695.24 t,占氮负荷的61.4%,残饵磷441.36 t,占磷负荷的65.0%,残饵是构成氮磷负荷的主要...     

对虾、青蛤和江蓠混养系统氮磷收支的实验研究

为减少养殖污水中营养盐的排放量,降低对近海水质的污染,采用海水陆基围隔实验法,对凡纳滨对虾(Litope-naeus vannamei)、青蛤(Cyclina sinesis)和菊花心江蓠(Gracilaria lichevoides)不同混养系统的氮(N)、磷(P)收支状况进行了实验研究。结果表明:实验中的单养组投放的饵料占N总输入的75.5%,占P总输入的93.6%,混养组投放的饵料占N总输入的54.7%~64.8%,占P总输入的81.6%~88.7%;在支出项目中,单养组和混养组收获的养殖生物分别占N总输入的25.0%和44.4%~51.5%,占P总收入的11.2%和25.1%~31.8%;底泥沉积N,P为其主要支出项目,单养组和混养组分别占总输入的45.1%和30.0~32.5%,68.3%和50.3%~57.1%,其中混养组N,P的底泥沉积量低于单养组。     

Nursery grounds of Tarakihi (Teleostei: Cheilodactylidae) around New Zealand

Nursery grounds of the tarakihi Cheilodactylus macropterus (Bloch & Schneider) were discovered in 1963–72 mainly off the south‐western coast of the North Island, in Tasman Bay, along the entire eastern coast of the South Island, and around the Chatham Islands. They occurred at depths of 20–100 m, and mostly between 10 km and 30 km from shore. The tarakihi nurseries had a dense and varied invertebrate bemthic epifauna dominated by sponges and small corals. Few signs of nurseries were found in. other New Zealand waters, in spite of the existence of major spawning grounds there. It is not known with which spawning grounds the various nursery grounds are linked.

The Tasman Bay nursery ground is 18–33 km wide and about 75 km long, with a surface area of about 2000 km². There is a rich demersal fish fauna (37 species were recorded) dominated by tarakihi, red gurnard Chelidonichthys kumu (Lesson & Garnot), snapper Chrysophrys auratus (Bloch & Schneider), and leathei'iacket Novodon convexirostris (Guenther). The young tarakihi occur at depths of 20–45 m and concentrate during winter in the warmer deeper water. They first appear in trawl catches in summer, towards the end of their first year (assumed birthdate is 1 March), and stay on the nursery until the age of 3 y. They occur in the deeper water off the nursery during their fourth and fifth year and depart during their sixth year, possibly for the spawning grounds off the west coast of the South Island. The mean lengths at the ages of 15, 27, and 39 months were 12.6, 18.0, and 24.0 cm respectively in 1970. There was some variation in growth rate within the nursery ground, but the age groups could nevertheless be recognised easily from, length frequency modes. Monthly modal lengths showed that growth slows down in winter. Evidence for fluctuations in year class strength was found; year classes 1966 and 1969 were weak and year class 1968 was strong.

The vulnerability of tarakihi less than 4y old to commercial New Zealand trawl gear is low, and the local fishing fleets do no serious damage to the habitat on the nursery grounds. However, a large part of the tarakihi nursery grounds off the east coast of the South Island lies outside the territorial fishing zone. Intensive fishing on these grounds by large foreign vessels using heavy trawl gear could have an adverse effect on the habitat of the young tarakihi in this region.     

近海沉积物中氮磷的生物地球化学研究进展

通过对国内外学者十几年来在近海沉积物氮磷地球化学方面研究工作的综述，阐明了该方面的最新进展。主要包括：沉积物中氮磷的形态及分布特点，各种形态间的分配关系，以及与氮磷迁移转化相关的循环过程。最后对该领域今后的发展方向进行展望。     

粤东柘林湾柱状沉积物中氮、磷的垂直分布

对柘林湾代表性水区柱状样沉积物中不同形态氮、磷的含量进行了分析,研究了其垂直分布规律及其历史演变趋势。研究结果显示,除湾西北三百门(S2站)和湾中央大规模网箱渔排养殖区中心(S6站)外,其余各测站柱状沉积物中的有机氮(TOM)、凯氏氮(TKN)及各形态磷含量基本呈现"沉降-降解-堆积"三阶段的分布特征,反映了成岩作用的结果。S2、S6测站柱状沉积物中的多项氮磷指标,在表层10 cm以深不降反升与这两测站的高污染压力和弱水体交换能力导致的污染物快速堆积有关。底栖动物对沉积物垂直方向的扰动可能是各氮磷指标在沉降和降解阶段产生波动变化的重要原因之一,但生物扰动对NH4 的垂直变化影响最大。自生磷(Au-P)与有机磷(OP)在表层以下随深度呈一定的镜像关系,与Au-P和OP在成岩过程中的相互转化有关。Au-P随深度的变化幅度比OP的大,表明磷在Au-P和OP之间的转移并不是磷再分配的唯一途径,其它形态的磷也可能参与磷的再分配,而两者在表层不呈镜像关系主要与微生物对两者的降解有关。     

哑铃湾网箱养殖水体中氮磷结构特征

根据2002年4月-2003年1月对哑铃湾网箱养殖的调查数据,分析了养殖水体中不同形态N／P值的分布趋势、季节变化及哑铃湾网箱养殖水体中的限制性营养盐。结果表明：各形态N／P具有显著的季节变化,其分布趋势基本表现为网箱养殖区低于非养殖区,并且随着养殖年限的增加,这种现象更明显。总体上说,哑铃湾浮游植物生长主要受P的限制,但从无机态N／P来看,春、夏季以P为该海域浮游植物生长的控制因子：秋、冬季以N为该海湾浮游植物生长的控制因子。     

微藻在污水中的除磷脱氮作用

初步调查了广州海珠区污水排放区污水中微藻的组成,表明该区微藻以蓝藻门颤藻科Ｏｓｃｉｌｌａｔｏｒｉａｃｅａｅ为主,以小颤藻Ｏｓｃｉｌｌａｔｏｒｉａｔｅｎｕｉｓ、两栖颤藻Ｏ．ａｍｐｈｉｌｉａ为优势种;测定了其在污水中的除磷脱氮能力,结果表明,两优势种处理污水氮、磷的能力随微藻的生长期和污水中氮、磷浓度的不同而有较大的变化。     

Nitrogen and phosphorus species in the coastal and shelf waters of Southeastern North Carolina, Mid-Atlantic U.S. coast

The diversity of small-scale wetlands, high salinity tidal creeks, salt marshes, estuaries, and a wide and shallow shelf with the Gulf Stream close to the break makes the coastal zone of south-eastern North Carolina (U.S.) a natural laboratory for the study of the cycling of nitrogen (N) and phosphorus (P) in coastal and shelf waters. We assessed the summer concentrations, forms, and ratios for each N (total dissolved N, nitrate + nitrite, ammonium and dissolved organic N) and P (total dissolved P, o-phosphate and dissolved organic P) pool as these nutrients travel from tidal creeks, salt marshes and two large estuaries to Long and Onslow Bays. Additionally, we measured ancillary physical (temperature, salinity and turbidity) and chemical (dissolved oxygen, chlorophyll a and pH) water properties. Highest concentrations of all individual N and P compounds were found in the upper parts of each tributary and were attributed to loads from agricultural and urban sources to the coastal watersheds, continuing downstream to receiving estuaries. In all areas, dissolved organic N and P species were predominant constituents of the total dissolved N and P pools (64–97% and 56–93%, respectively). The lower parts of estuaries and surface shelf waters were characterized by oceanic surface values, indicating removal of N and P downstream in all tributaries. The different watershed and hydrological characteristics also determined the different speciation of N and P pools in each estuary. Despite a high level of anthropogenic pressure on the uppermost coastal waters, there is self-regulation in this coastal ecosystem with respect to human perturbations; i.e. significant amounts of the N and P load are retained within estuarine and nearshore waters without reaching the shelf.     

Eutrophication In Lake Rotorua. 2. Using ROTAN and OVERSEER to model historic,present and future nitrogen loads

OVERSEER is used in New Zealand to estimate nutrient losses from farmland, but does not quantify subsequent movement through the catchment, or attenuation. This paper uses the ROTAN model, based on the Scandinavian HBV-N model, to route nitrogen losses from 1900–2015 to Lake Rotorua where groundwater age ranges from 14 to 170 years. ROTAN conceptualises three delivery pathways (quickflow, groundwater and streamflow) with different attenuation. When calibrated to measured stream and groundwater concentrations, several combinations of attenuation gave equally good fits largely because of sparse and uncertain input and calibration data. Nevertheless, lake N loads were predicted for current land use (754?±?39?t y^?1) and with proposed N loss reductions (431?±?26?t y^?1). Probabilities were also calculated that the reductions are more (12%–18%) or less (82%–88%) than required to meet the target lake N load (405?t y^?1). ROTAN shows promise for calculating nitrogen movement in catchments dominated by groundwater where there is limited data.     

珠江口海域无机氮和活性磷酸盐含量的时空变化特征

主要利用1998年在珠江口海域连续同步观测资料，研究该海域无机氮、活性磷酸盐含量和富营养化状况。结果表明，无机氮主要来自四个口门的径流，但深圳湾附近的陆源亦有一定贡献；无机氮的形态主要以硝酸氮为主，而在深圳湾附近海域则以氨氮为主；无机氮含量普遍超过0．30mg/dm^3的我国海水水质标准二类标准值，大部分海域已超过0．50mg/dm^3的四类水质标准值，径流对活性磷酸盐含量的贡献不显著，而深圳湾附近的陆源则有明显的贡献，从珠江口附近由沿岸流和涨潮流带来的活性磷酸盐亦有明显的影响；除深圳湾附近海域活性磷酸盐含量超过0．030mg/dm^3的二类海水水质标准值外，其他海域基本符合0.015mg/dm^3的一类海水水质标准值要求。该海域的N／P值普遍较高，而且北部海域的高于南部海域；最高值超过300，最小值也大小30；该水域的营养盐主要为磷限制。     

海洋围隔中异养细菌与环境中氮、磷关系的研究

利用海洋围隔生态系统实验装置,向海水中施加不同浓度的氮和磷,研究海洋异养细菌与海水环境中氮、磷的关系。结果表明,实验开始后海洋异养细菌的数量就迅速增加,并且一直维持在较高水平,第7~8天达到峰值。但在海洋异养细菌数量达到峰值后,海水中氮和磷的浓度有所回升,磷元素促进了海洋异养细菌的快速生长和繁殖,同时海洋异养细菌在一定程度上也利用了无机氮,海洋异养细菌的数量与海水环境中氮和磷的浓度具有较好的正相关性。     

海水中磷氮不同形态的同时测定

采用过硫酸钾-硼酸-氢氧化钠混合试剂作为氧化剂,同时测定海水中总磷、氮和总溶解态磷、氮,从而建立了海水中磷、氮不同形态的分析流程及步骤。总磷、总溶解态磷浓度为0.35～1.09μmol/dm3时,相对标准偏差小于6.6%;总氮、总溶解态氮浓度为11.8～54.8μmol/dm3时,相对标准偏差小于5.6%。总磷、总溶解态磷和总氮、总溶解态氮的回收率分别为95.0%～106.0%和94.0%～106.0%。本文的分析方法可用于对近岸海水及河口水中磷、氮不同形态的同时测定。     

Modelling nitrogen and phosphorus cycles and dissolved oxygen in the Zhujiang Estuary Ⅰ. Model development

wrmcrloxHuman activities related to the population growth and developrnent of industry and rnwhci-pality have led to the incrouing hadings of various POllutants into estudries during the past fewdecades. These increasing edlutant lOadings have caused declined estuallne hedth which can bemereured by a vdriety of indices. In order to obtain solutions to environrnent problerns, re-sources manageTnnt apencies are supporting a holistic approach to envirorirnental management.An effcient strategy t…     

Seasonal changes in nitrogen and phosphorus transport in the lower Changjiang River before the construction of the Three Gorges Dam

Water and sediment samples were collected at Datong from June 1998 to March 1999 to examine seasonal changes in the transports of nitrogen (N) and phosphorus (P) from the Changjiang River (Yangtze River) to the East China Sea (ECS). Dissolved inorganic nitrogen (DIN; dominated by nitrate) concentration exhibited small seasonality, and DIN flux was largely controlled by water discharge. Dissolved inorganic phosphorus (DIP) concentration was inversely correlated with water discharge, and DIP was evenly delivered throughout a year. The transports of DIN and DIP from the Changjiang River were consistent with seasonal changes in nutrient distributions and P limitation in the Changjiang Estuary and the adjacent ECS. Dissolved organic and particulate N (DON and PN) and P (DOP and PP) varied parallel to water discharge, and were dominantly transported during a summer flood. The fluxes of DOP and particulate bioavailable P (PBAP) were 2.5 and 4 times that of DIP during this period, respectively. PBAP accounted for 12–16% of total particulate P (PP), and was positively correlated with the summation of adsorbed P, Al–P and Fe–P. Ca–P, the major fraction of PP, increased with increasing percent of CaCO₃. The remobilization of riverine DOP and PBAP likely accounted for the summer elevated primary production in DIP-depleted waters in the Changjiang Estuary and the adjacent ECS. The Changjiang River delivered approximately 6% of DIN (1459 × 10⁶ kg), 1% of DIP (12 × 10⁶ kg), and 2% of dissolved organic and particulate N and P to the totals of global rivers. The construction of the Three Gorges Dam might have substantially reduced the particulate nutrient loads, thereby augmenting P limitation in the Changjiang Estuary and ECS.     

不同池塘养殖模式的环境氮磷负荷及其水质特征

2008年3月至2009年1月研究了广东海丰县东关联安围湿地两种投饵养殖模式——对虾主养(半集约化养殖)和虾蟹混养(半集约化养殖)海水池塘的环境氮磷负荷和养殖水体氮磷含量的周年变化情况,并以不投饵的塭围虾贝混养(粗放式养殖)模式为对照。3种模式中,池塘单位面积环境氮、磷负荷以对虾主养模式最高,分别为36.52 kg/hm2和7.39 kg/hm2;虾蟹混养模式次之,分别为1.49 kg/hm2和0.52kg/hm2;而塭围虾贝混养模式最低,分别为–2.47 kg/hm2和–0.34 kg/hm2。每月1次对3种模式养殖过程中水体的总氮、硝酸氮、亚硝酸氮、氨氮和总磷及磷酸盐含量进行监测,结果表明,与养殖环境氮磷负荷大小相对应,塭围虾贝混养池塘水质最好,虾蟹混养池塘次之,而对虾主养池塘水质最差,这种现象尤其在养殖后期更为明显。     

环渤海湿地盐地碱蓬对碳、氮、磷吸收通量的研究

主要调查环渤海湿地的盐地碱蓬对碳、氮、磷的吸收通量。调查表明,环渤海湿地的盐地碱蓬面积为7 397 hm2。2009年7月、10月和11月盐地碱蓬总生物量(干重)分别为2.104×104t、2.615×104t和1.523×104t。7月、10月和11月,盐地碱蓬对碳的吸收通量分别为6 577 t、8 538 t和5 713 t;对氮的吸收通量分别为201.2 t、278.6 t、177.7 t;对磷的吸收通量分别为17.00 t、32.40 t、16.60 t;盐地碱蓬对碳、氮、磷的最大吸收通量均为10月。     

A nitrogen and phosphorus dynamic model of mesocosm pelagic ecosystem in the Jiaozhou Bay in China

A nitrogen and phosphorus dynamic model of mesocosm pelagic ecosystem was established according to the summary and synthesis of the models available, in which seven state variables （DIN, PO4-P, DON, DOP, phytoplankton, zooplankton and detritus） were included. Logically it had five modules--phytoplankton, zooplankton, dissolved inorganic nutrients, dissolved organic nutrients and detritus. The results showed that this model could simulate the variations of DIN, PO4-P, DON, DOP, POC and phytoplankton biomass in pelagic ecosystem in mesocosm properly, based on the site experiment data in the Jiaozhou Bay in the autumn of 1999 and the summer of 2000. Not only the logical structure but also the model parameters were feasible, and about 20 parameters were made to fit for the Jiaozhou Bay during the simulation. All of these are necessary to study the control mechanism of nutrients biogeochemical cycling in the Jiaozhou Bay and other China＇ s coastal waters.     

闽江河口陆源入海排污口现状及氮磷排放调查

闽江口海域是福建最重要的经济发展区,但也存在许多环境污染问题。2018年10—12月,对闽江入海口区域的陆源入海排污口开展调查和监测。本次共调查93个排污口,主要分布在琅岐岛（34.4%）和粗芦岛（20.4%）上。入海排污口的类型以设闸排污口为主,共调查有52个,占调查总数的55.9%,主要分布在琯头镇区域（17个）和琅岐岛（12个）。监测结果表明,闽江河口海域陆源排污口的氨氮、总氮和总磷超标严重,五类水质和劣五类水质样品分别占29.9%和37.7%。其中,设闸排污口的劣V类和V类水质样品最多,其次是自然径流。从区域来看,在琯头镇的劣V类和V类水质样品共有18个,占该镇排污口样品总数的90%。水质样品的最高监测浓度为：氨氮-20.2 mg/L,总氮-27.0 mg/L,总磷-2.86 mg/L,氨氮浓度已经超过《污水综合排放标准》的一级标准（15 mg/L）。闽江河口陆源入海排污口的污染物主要来源于农村和农业面源污染。针对排污口排污超标情况严重问题提出了加强农村面源污染监管和控制、开展重要排污口重点治理工程、开展陆源入海排污口详查等相应的措施和建议,为闽江河口陆源入海排污口整治提供科学支撑。