镇海水库拟柱孢藻的分离鉴定和氮磷对其生长的影响

以分离自广东省镇海水库的拟柱孢藻N8为对象, 探究其在不同磷浓度及氮磷浓度组合下的生长情况。结果表明, 拟柱孢藻N8对磷的适应范围很宽, 在0.025.12 mg/L磷浓度下均能生长, 最适生长磷浓度范围为0.165.12 mg/L, 磷浓度的升高能显著延长拟柱孢藻的对数生长期和提高生物量。动力学分析表明, 拟柱孢藻N8有较低的KSP值, 对磷元素的亲和性较高, 在磷营养贫乏的环境下更容易形成优势。在氮磷组合实验中, 低氮(0.5 mg/L)显著抑制拟柱孢藻的生长, 且这种生长抑制不受磷浓度的影响; 而在低磷(0.04 mg/L)条件下, 水体中氮浓度的增加会显著促进拟柱孢藻的生长, 拟柱孢藻在高氮中磷和高氮高磷下的生长显著优于其他氮磷组合条件。研究表明, 广东省水库拟柱孢藻的生长受磷的限制较弱, 氮是其生长的决定因子。       

氮磷浓度对藻-溞-草间相互作用的影响

为了解氮磷浓度对生物操纵效果的影响, 以小球藻、大型溞和金鱼藻分别作为浮游植物、浮游动物和大型沉水植物的代表, 建立了它们之间相互作用的水生微宇宙模型。研究了在25℃、2000—3000 lx 的温度和光照下, 不同氮磷浓度对三者生长的影响。结果表明: 两者共培养时, 在高氮(10.5 mg/L)条件下, 磷浓度小于0.1 mg/L 对大型溞繁殖和金鱼藻的生长有利; 磷浓度介于0.1—2 mg/L 时小球藻呈大暴发趋势, 而金鱼藻的生长则明显受抑制。在低氮(0.5 mg/L)条件下, 磷浓度不大于0.5 mg/L, 大型溞对小球藻有较好的抑制作用, 金鱼藻与小球藻无显著互抑现象; 磷浓度增大为2 mg/L 时, 小球藻对金鱼藻生长产生明显抑制。在0.05—2 mg/L 的磷浓度范围及高氮和低氮条件下三者共培养时, 大型溞数量及金鱼藻生物量均不同程度的升高,且小球藻数量得到了有效抑制, 以磷浓度为0.1—0.5 mg/L 时效果最佳; N/P 比值对藻、溞、草间的相互作用有重要影响, 在藻-溞系统中, 大型沉水植物的加入可以大大提高控藻效果, 减小N/P 比值波动带来的不利影响。与低氮情况相比, 高氮条件对金鱼藻、大型溞及小球藻的增长均存在一定抑制作用。磷浓度为0.5 mg/L时的水体氮磷去除效果好于其他磷浓度梯度。       

毛枝藻对人工污水脱氮除磷能力的研究

文章探究了2株毛枝藻(Stigeoclonium sp.)SHY-370及HB1617在不同初始氨氮浓度以及不同氮磷比条件下的生长情况与氮磷去除能力。结果表明氨氮浓度对2株毛枝藻的生长及TP去除能力均有一定的影响, SHY-370可耐受最大氨氮浓度为10 mg/L, HB1617为5 mg/L;氨氮浓度为1—10 mg/L时SHY-370及HB1617对其去除率均达到97%以上,最大去除速率为3.98 mg/(L·d)。氮磷比对SHY-370的生长影响不大,但在氮磷比大于20时HB1617的生长受到抑制; SHY-370对NO_3~--N去除的最佳氮磷比为10—40, HB1617为2—10;氮磷比为2时水体中TP的含量超过了SHY-370及HB1617所能去除的最大值,去除率较低。实验结果表明SHY-370及HB1617在污水深度脱氮除磷方面具有一定的潜力,可考虑将其应用于城市生活污水二级出水(TN≤15 mg/L、TP≤0.5 mg/L、 NH_4~+-N≤5 mg/L)的深度处理。     

引黄水库藻类变化特征及其影响因素研究

以济南鹊山引黄水库为研究对象,系统研究了2008-2012 年间其水中浮游藻类的种类和数量变化特征以及藻类细胞密度与总氮、总磷浓度的相关性,并在实验室模拟条件下分析了温度、光照、氮磷营养盐等条件对其藻类生长影响。结果表明,该水库水藻密度年际、年内变化较大,年平均值均在500 万个/L 以上,藻种共7 个门,37 个属,蓝藻和硅藻为水库的优势藻种。该水库藻类生长的最佳温度为25℃,光强为3 000 lx,氮磷营养盐对藻类生长影响排序为硝酸盐>磷酸盐>亚硝酸盐>氨氮。磷可能是藻生长的限制性因子,在夏、秋季及水库磷浓度大幅变化时易发生水华。     

重要环境因子对小球藻去除污水中氮磷的影响

对小球藻去除污水中氮磷的性能进行了研究,考察了初始氮磷浓度、氮磷比、光照条件和pH等因素对其去除效率的影响。结果表明,在初始氮磷浓度分别在35 mg/L和7 mg/L以下时去除率接近100%;氮磷比为5∶1和10∶1,小球藻第4 d基本完全去除了污水中的氨态氮,而氮磷比对小球藻的除磷能力没有显著影响;在初始氨态氮或总磷浓度相同的条件下,光照条件(L/D为24 h∶0 h和12 h∶12 h)对氮磷去除效果的无明显差异性（P＞0.05）,而随着氮磷浓度的增加,连续光照条件逐渐展现出去除氮磷的优势;小球藻在pH 7～8范围内对氨态氮的去除率最佳,pH 5～7范围内,对总磷的去除率最佳。     

温度和氮磷浓度对平裂藻和栅藻生长及竞争的影响

为了解温度及氮磷浓度对平裂藻和栅藻生长及竞争的影响,分别在18、25和35℃条件下,以BG11培养基为基础,设置了不同的氮磷浓度组,进行了2种藻的单独培养试验和混合培养试验,结果表明:在纯培养条件下,低营养浓度组(磷浓度分别为0.1和0.5 mg/L)平裂藻在3种温度下基本停止生长,高营养盐浓度组(磷浓度分别为1.0和1.5 mg/L)除18℃1.0 mg/L组停止生长外,其余均能正常生长增殖,且细胞最大密度表现为25℃ 18℃ 35℃, 1.5和1.0 mg/L浓度组细胞生长差异不显著。栅藻在纯培养条件下,细胞密度总体表现为随着营养盐浓度升高而增加的趋势,细胞最大密度表现为18℃ 25℃ 35℃。在混合培养试验中,除35℃、1.5 mg/L组平裂藻对栅藻的竞争抑制参数大于栅藻对平裂藻的竞争抑制参数外,其余试验组均表现为栅藻受平裂藻影响较小。在混合培养体系中, 0.1 mg/L组平裂藻仍基本停止生长, 0.5 mg/L组受栅藻的刺激作用,生长优于纯培养体系。1.0和1.5 mg/L组均受栅藻的抑制作用,且浓度越高抑制作用越强。       

斜生栅藻在不同磷条件下氮生态幅的研究

为获得斜生栅藻（Scendesmus obliquus）的氮生态幅,研究根据中华人民共和国地表水环境质量标准磷浓度界定,利用谢尔福德（Shelford）耐受定律进行曲线拟合对斜生栅藻在低磷（0.02 mg/L）、中磷（0.2 mg/L）和高磷（0.4 mg/L）三种不同磷浓度下氮的生态幅进行定量表达,获得三种磷起始条件下斜生栅藻生长的最佳氮浓度、氮适宜生长范围和氮耐受范围。研究表明,在三种磷条件下斜生栅藻生长的最佳氮浓度分别为1.02、8.91和18.05 mg/L,对应的最大比生长速率分别为（0.1420.006）、（0.3140.002）和（0.3460.007） /d,氮适宜生长范围分别为（0.521.52）、（4.4813.34）和（11.7224.38） mg/L,氮耐受限度分别为（0.022.02）、（0.0517.77）和（5.3930.71） mg/L。这表明富营养化水体可能引起斜生栅藻的大量生长、繁殖,也暗示了斜生栅藻能作为高氮水环境的一个良好指示生物。       

氮磷对青岛大扁藻和牟氏角毛藻单养和共培养生长的影响

通过实验生态学的方法,分别以KNO3和KH2PO4为氮源和磷源,研究青岛大扁藻(Platymonas helgolandicavar.tsingtaoensis)和牟氏角毛藻(Chaetoceros muelleri Lemmerman)单培养和共培养时的生长状况。结果显示,不同氮磷处理对两种藻的单培养和共培养都有显著影响(P<0.05)。共培养时,青岛大扁藻的最大藻密度与氮磷浓度呈正相关。氮处理时,当培养液中KNO3为110 mg/L时,取得最大值;磷处理时,青岛大扁藻的最大藻密度在KH2PO4为9 mg/L时取得最大值;而牟氏角毛藻分别在KNO3为70 mg/L和KH2PO4为5 mg/L时取得最大值。共培养时两种藻的藻密度都低于单培养。另外,无论低氮高磷还是高氮低磷都不利于两种藻获得较大的终细胞密度。     

N、P营养盐胁迫对两株布朗葡萄藻生长的影响

采用批次培养方法,在光照强度60、110mol/m2s下分别设置了7个不同的氮、磷浓度(N:0-3500g/L,P:15-775g/L),研究两株布朗葡萄藻(Botryococcus braunii)对氮、磷胁迫的敏感性差异,筛选高营养利用效率的优良藻株。结果表明:两株藻对氮磷营养胁迫的耐受性存在差异,B.braunii764株对氮胁迫具有较高耐受性,而B.braunii765株对磷胁迫具有较高耐受性。光照强度110mol/m2s,不同氮浓度下B.braunii764株其平均生长速率均显著高于其他各处理组;不同磷浓度下B.braunii765株其平均生长速率显著高于B.braunii764株。在试验设定的光照强度条件下,适当增加光照强度能够显著降低氮胁迫对布朗葡萄藻生长的抑制效应。在光照强度110mol/m2s下,氮浓度3500g/L时两株布朗葡萄藻平均生长速率与在正常Chu-10培养基条件下无显著差异。磷浓度775g/L时两株布朗葡萄藻的平均生长速率均显著低于正常Chu-10培养基条件,增加光照强度对磷胁迫下藻细胞的生长无显著作用。两株布朗葡萄藻在第2天时磷吸收与初始磷浓度呈正相关关系,氮吸收在3500g/L时出现饱和现象。布朗葡萄藻的生长更容易受到培养基中磷营养胁迫的影响。       

磷浓度对铜绿微囊藻、大型溞和金鱼藻三者相互作用的影响

为了解磷浓度对生物操纵和水生植被恢复效果的影响,以铜绿微囊藻、大型溞和金鱼藻分别作为浮游植物、浮游动物和大型沉水植物的代表,在25℃、2000—3000lx光强和11mg/L氮浓度条件下,研究两者和三者共培养时4种磷浓度(0.2、0.5、1.0、1.5 mg/L)下各自的增长率和培养液中氮磷去除率的变化。结果表明:两者共培养时,磷浓度不大于0.2mg/L时,有利于大型溞的繁殖和金鱼藻的生长;磷浓度介于0.5—1.5mg/L时,铜绿微囊藻呈正增长趋势,而金鱼藻的生长则明显受抑制。三者共培养时,所有磷浓度下的大型溞数量及金鱼藻生物量均不同程度的升高,且铜绿微囊藻的生长得到了有效抑制,以磷浓度为0.2—0.5mg/L时效果最佳;N/P比值对藻、溞、草间的相互作用有重要影响,在藻-溞系统中,大型沉水植物的加入可以大大提高抑藻效果,减小N/P比值波动带来的不利影响。磷浓度为0.5mg/L时的水体氮磷去除效果好于其他磷浓度梯度。     

Effects of limiting nutrients and N:P ratios on the phytoplankton growth in a shallow hypertrophic reservoir

The purpose of this study was to evaluate the effects of limiting nutrients and the N:P ratios on the growth of phytoplankton (mainly cyanobacteria) in a shallow hypertrophic reservoir between November 2002 and December 2003. Nutrient enrichment bioassays (NEBs) were conducted, along with analyses of seasonal ambient nutrients and phytoplankton taxa, in the reservoir. The average DIN:TDP and TN:TP mass ratios in the ambient water were 90 (range: 17–187) and 34 (13–60), respectively, during the study period. The dissolved inorganic phosphorus showed seasonal variation, but less than that of inorganic nitrogen. The TN:TP ratios ranged from 13 to 46 (mean: 27 ± 6) during June–December when the cyanobacteria, Microcystis, dominated the phytoplankton composition. The NEBs showed that phytoplankton growth was mainly stimulated by the phosphorus (all of total 17 cases), rather than the nitrogen concentration (8 of 17 cases). The rapid growth rate of cyanobacteria was evident with TN:TP ratios less than 30. According to the results of the NEBs with different N concentrations (0.07, 0.7 and 3.5 mg l⁻¹), but the same N:P ratios and when the nitrogen concentration was highest, the cyanobacterial growth reached a maximum at N:P ratios <1. Overall, the response of cyanobacterial growth was a direct function of added phosphorus in the NEBs, and was greater with increased N concentrations. Thus, cyanobacterial blooms favored relatively low N:P ratios in this hypertrophic reservoir system. An erratum to this article is available at .     

基于氮磷比解析太湖苕溪水体营养现状及应对策略

生态化学计量学是评价水体营养状态的重要手段,利用其氮磷比指标探讨了我国太湖主要入湖河流苕溪的营养状态。野外监测结果显示,苕溪水体氮素超标严重,磷素污染轻度,硝酸盐、颗粒态磷为氮磷的主要赋存形态,且氮磷浓度呈现相似的季节变化规律,表明苕溪主要受农业面源污染影响。氮磷比分析表明,苕溪水体春、秋季处于磷素限制状态,夏季适合藻类生长,冬季低温条件下不利于藻类的大量繁殖;苕溪生物量增长受磷素限制,线性拟合亦显示其氮磷比主要受磷素波动的调控;苕溪干流大面积暴发蓝藻水华的风险较部分支流及死水区低,苕溪水入湖后,特别是夏季其暴发风险将显著提高。针对苕溪水体的富营养化现状,提出若干条水质改善应对策略。     

Seasonal pattern in nutrient limitation and grazing control of the phytoplankton community in a non-stratified lake

1. The relative importance of zooplankton grazing and nutrient limitation in regulating the phytoplankton community in the non-stratified Lake Kvie, Denmark, were measured nine times during the growing season.
2. Natural phytoplankton assemblage bioassays showed increasing importance of nutrient limitation during summer. Growth rates at ambient nutrient concentrations were continually below 0.12 per day, while co-enrichment with nitrogen (N) and phosphorus (P) to above concentration-saturated conditions enhanced growth rates from May to the end of July.
3. Stoichiometric ratios of important elements in seston (C : N, C : P, N : P), in lake water (TN : TP), in external loading (TN : TP) and in internal loading (DIN : DIP) were measured to determine whether N or P could be the limiting nutrient. TN : TP molar ratio of both lake water, benthic fluxes and external loading suggested P limitation throughout the growing season. However, seston molar ratios suggested moderate P-deficiency only during mid-summer.
4. Abundance and community structure of the zooplankton varied considerably through the season and proved to be important in determining the responses of algal assemblages to grazing. High abundance of cladocerans and rotifers resulted in significant grazing impact, while cyclopoid copepods had no significant effect on the phytoplankton biomass.
5. Regeneration of ammonium and phosphate by zooplankton were periodically important for phytoplankton growth. A comparison of nutrient regeneration by zooplankton with nutrient inputs from sediment and external sources indicated that zooplankton may contribute significantly in supplying N and P for the growth of phytoplankton.     

Effects of nitrogen,phosphorus, iron and silicon on growth of five species of marine benthic diatoms

The effects of nitrogen, phosphorus, iron and silicon on growth of five species of marine benthic diatoms, namely Navicula patrickae, Nitzschia panduriformis, Navicula thienemannii, Nitzschia longissima and Navicula atomus were studied by single factor experiments and the optimal concentration ratios of the four nutrient elements beneficial for diatoms growth were screened out separately using the L₉ (3⁴) orthogonal design. The results highlighted that nitrogen, phosphorus, iron and silicon all had highly significant effects on growth of five diatoms while the diatoms growth rates reached the highest averagely in the 2nd to the 6th culture day. In addition, the optimal concentrations (mg/L) of four nutrients suitable for diatoms growth were found higher than that in f/2 medium except that Nitzschia longissima had the same concentration of nitrogen as that in f/2 medium which is optimal for growth. Moreover, the optimal growth concentrations of four elements for five diatoms varied in the range of 12.36–74.16 mg/L for nitrogen, 1.70–3.98 mg/L for phosphorus, 2.00–4.00 mg/L for iron, 23.01–69.03 mg/L for silicon, respectively. By means of the orthogonal test of four nutrients for five benthic diatoms, the optimal concentration ratios N:P:Fe:Si (mg/L) were obtained as follows: 74.16:2.27:3.33:23.01 for N. patrickae; 37.08:3.98:4.00:11.50 for N. panduriformis; 49.44:3.98:3.33:34.51 for N. thienemannii; 12.36:1.70:4.00:11.50 for N. longissima; 74.16:2.27:4.00:69.03 for N. atomus.     

Factors controlling the growth of field populations of Hydrodictyon reticulatum in New Zealand

Since Hydrodictyon reticulatum was introduced to New Zealand it has spread rapidly and produced persistent annual nuisance growths in areas where nuisance algal had not occurred previously. Field bioassays were conducted at 10 sites between August 1993 and February 1995 to evaluate the seasonal growth patterns and the factors controlling growth under natural conditions. H. reticulatum exhibited a strong seasonal growth pattern with growth rates up to 0.33 doublings d^-1 from August to March, are duction in growth rate in April and little or no growth from May to July. The H. reticulatum present in New Zealand has are latively low requirement for dissolved inorganic nitrogen (DIN) in comparison with other nuisance species, with its growth rate being saturated at 200 mg m^-3. This and the high affinity for DIN as shown by a K_s of 29 mg m^-3 have been key factors in the establishment of nuisance growths of H. reticulatum in New Zealand. This revised version was published online in August 2006 with corrections to the Cover Date.     

保安湖沉积物和间隙水中氮和磷的含量及其分布

保安湖沉积物中氮(N)的含量平均为5.20mg/g,平面分布以桥墩湖区含量最高。沉积物中磷(P)的含量平均为0.75mg/g,平面分布以扁担塘湖区含量最高。沉积物间隙水中总氮的平均含量为3.63mg/L,无机氮中以氨氮的含量最高,占总氮的57.2%;间隙水中总磷的含量平均为0.098mg/L,磷酸盐占总磷的50.0%.间隙水中氮和磷含量的平面分布差异不明显。间隙水中氮和磷的含量比湖水中含量高,但除氨氮外,一般不超过5倍,表明湖水和沉积物间隙水之间营养交换十分强烈。       

Seasonal Patterns of Nitrogen and Phosphorus Limitation in Four German Lakes and the Predictability of Limitation Status from Ambient Nutrient Concentrations

To identify the seasonal pattern of nitrogen (N) and phosphorus (P) limitation of phytoplankton in four different lakes, biweekly experiments were conducted from the end of March to September 2011. Lake water samples were enriched with N, P or both nutrients and incubated under two different light intensities. Chlorophyll a fluorescence (Chla) was measured and a model selection procedure was used to assign bioassay outcomes to different limitation categories. N and P were both limiting at some point. For the shallow lakes there was a trend from P limitation in spring to N or light limitation later in the year, while the deep lake remained predominantly P limited. To determine the ability of in-lake N:P ratios to predict the relative strength of N vs. P limitation, three separate regression models were fit with the log-transformed ratio of Chla of the P and N treatments (Response ratio = RR) as the response variable and those of ambient total phosphorus:total nitrogen (TN:TP), dissolved inorganic nitrogen:soluble reactive phosphorus (DIN:SRP), TN:SRP and DIN:TP mass ratios as predictors. All four N:P ratios had significant positive relationships with RR, such that high N:P ratios were associated with P limitation and low N:P ratios with N limitation. The TN:TP and DIN:TP ratios performed better than the DIN:SRP and TN:SRP in terms of misclassification rate and the DIN:TP ratio had the highest R² value. Nitrogen limitation was predictable, frequent and persistent, suggesting that nitrogen reduction could play a role in water quality management. However, there is still uncertainty about the efficacy of N restriction to control populations of N₂ fixing cyanobacteria.     

生物浮岛与漂浮植物对开放池塘水质净化效果

采用自主研发流量可控的密闭漂浮性水槽开展河道原位模拟实验, 研究了挺水植物菖蒲(种植于浮岛上)与漂浮植物凤眼莲对受到城市污水污染的开放池塘水质净化效果以及系统中氮磷等污染物的归趋。结果表明, 菖蒲和凤眼莲对水体藻类密度和叶绿素a削减率达到90%以上, 对COD_Mn浓度削减率达到45%以上。经过10 m长水槽后, 种植了凤眼莲的水槽水体其TN和TP浓度分别由3.71和0.24 mg/L降低至1.71和0.09 mg/L, 而设置有菖蒲浮岛的水槽其水体TN和TP浓度则分别降低至2.69和0.16 mg/L。在水体N、P的总削减量中, 凤眼莲吸收作用分别占84.31%和77.52%, 而在菖蒲浮岛系统中, 菖蒲的吸收作用仅分别占7.72%和8.55%, 菖蒲净化系统中氮、磷的物理沉淀量显著高于凤眼莲组, 分别达到35.26%和51.58%, 但仍有57%和39%以上的氮和磷去向未知, 推测可能与浮岛上生长的生物膜有关。研究结果可为选用凤眼莲和浮岛植物修复技术进行污染水体生态修复理论研究与实践运用提供借签和参考。     

Nutrient-phytoplankton relationships in a tropical meromictic soda lake

Seasonal variation through one year in total nitrogen (TN), total phosphorus (TP), phytoplankton biomass, phytoplankton species composition and other environmental factors were examined in Lake Sonachi, a tropical meromictic soda lake. Mean concentrations of TN and TP were 11 000 µg N l^-1 and 100 µg P l^-1, respectively. Maximum concentrations of TN and TP occurred in the monimolimnion. Phytoplankton biomass ranged from 350 to 1260 mg m^-3. Synechococcus bacillaris, a small coccoid cyanophyte, dominated the phytoplankton. The mean chlorophyll a concentration of 37 mg · m^-3 was a modest value when compared with those of other tropical soda lakes. High TN:TP ratios indicated phosphorus limitation in the lake.     

鄱阳湖湿地两种优势植物叶片C、N、P动态特征

2011年2—6月在鄱阳湖南矶湿地国家级自然保护区逐月测定了灰化苔草(Carex cinerascens)、南荻(Triarrhena lutarioriparia)叶片C、N、P含量及其地上生物量,以阐明鄱阳湖湿地优势植物C、N、P含量及化学计量比动态特征与控制因子,探讨湿地养分利用与限制状况。结果表明：1）两种优势植物叶有机碳含量变化范围分别为365.3—386.6 mg/g和352.6—393.2 mg/g,平均值(?标准差)分别为(375.5?17.4) mg/g和(371.7?12.5) mg/g;叶N含量分别为6.96—17.59 mg/g和5.50—20.68 mg/g,平均值分别为(11.35?1.40) mg/g和(11.54?0.84) mg/g;叶P含量变化范围为0.65—2.14 mg/g和0.57—2.25 mg/g,平均含量为(1.56?0.69) mg/g和(1.55?0.68) mg/g。两种植物C:N、C:P、N:P平均值分别为37.65、413.60、9.62和41.05、410.29、9.57,C、N、P及其化学计量比种间差异不显著(P>0.05)。2）气温与地上生物量是N、P及其化学计量比季节变化的主要控制因子,气温和生物量对两种优势植物叶片氮、磷含量的影响要高于对叶有机碳含量的影响。3）植物C:N、C:P与地上生物量变化趋势基本一致,显示N、P养分利用效率随植物的快速生长而提高;根据两种优势植物及土壤N、P含量与化学计量比来判断,研究区植物更多地受氮限制。