首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 875 毫秒
1.
着重研究了红海湾养殖区底质水中 NO-3 -N、NO-2 -N、NH 4-N、PO3 -4 -P、有机质及 c( NO-3 -N) /c P 和 ∑c N/c P( ∑c N=c( NO-2 ) c( NO-3 ) c( NH 4) )比值的分布特征 ,并对该湾低质水中氮、磷及有机质的季节变化及其它们之间的相互关系作了讨论 ,结果表明 :在春、夏、冬三个季节中 ,NH 4-N的浓度比NO-2 -N及 NO-3 -N高 ,春季 NH 4-N的平均浓度为 92 .60 μm ol/L,占总无机氮 80 .57% ;夏季浓度为4 7.0 4μmol/L ,占总无机氮 61 .64 % ;冬季 NH 4-N的浓度最低 ,为 9.60μmol/L ,占总无机氮 4 5.76% ;而夏季 PO3 -4 -P浓度及有机质的含量比春、冬季高 ,分别为 53 .68μm ol/L和 1 .3 62 %。分析指出该湾底质水中无机氮是以 NH 4-N为主要存在形态。  相似文献   

2.
氮素作为生态系统功能和过程的重要限制性因子,其平衡和收支研究对于深入理解和分析河流非点源污染具有十分重要的意义。利用野外原位定点采样法,通过测定降水前后岷江中游成都段河流水体中NH4+-N(铵态氮)、NO3--N(硝态氮)和DIN(总无机氮)浓度,分析了氮素污染物特征值在干、湿季节空间分布差异及其影响因素。研究结果表明:(1)NH4+-N、NO3--N和DIN浓度均在10月达到最大值,而NH4+-N和DIN在3月达到最低,NO3--N在4月达到最低,且湿季的NO3—N、DIN含量显著高于干季。(2)NH4+-N含量表现出沙河府河江安河清水河,NO3--N和DIN含量均为府河沙河江安河清水河,且NH4+-N和DIN含量在下游河段出现富集效应。(3)三种形态氮素均与前三个月、前一个月的累计降水量之和成显著的正相关关系,前三个月的累计降水量之和的变化可分别解释NH4+-N、NO3--N和DIN浓度在不同季节77%,98%和89%的差异,前一个月的累计降水量之和的变化可分别解释NH4+-N、NO3--N和DIN浓度在不同季节77%,79%和66%的差异。  相似文献   

3.
2013年1~12月对湖光岩玛珥湖水体的叶绿素a和水质因子进行周年的逐月监测,探讨叶绿素a与水质因子的相关关系,并应用修正的卡尔森营养状态指数(TSI)对该湖泊的营养状态进行分析评价。结果表明,湖光岩玛珥湖水体叶绿素a含量的变化范围为1.08~4.22μg·L-1。氮磷比年均值为20.9,磷为营养限制因子,氮、磷共同限制浮游植物的生长。影响叶绿素a含量的主动因子与叶绿素a之间的Pearson相关系数大小关系为:r(NH4+-N)r(DO)r(NO2--N)r(TP)r(TN)r(NO3--N),其中NH4+-N与叶绿素a含量呈极显著正相关,r(NH4+-N)=0.907,NH4+-N为调控该湖泊浮游植物生长最关键的水质因子。水体TSI值的全年变化范围为34.6~48.0,其中1、2、3月的TSI37,属贫营养型;而其他月份为38TSI53,属中营养型;从全年分布来看,湖光岩玛珥湖属贫-中营养型。  相似文献   

4.
Eutrophication, which is the enrichment of a water mass with inorganic and organic nutrients that support plant growth, is a key factor in stimulating phytoplankton growth. In this study, we determined the effects of various nitrogen sources, different nitrogen concentrations in the culture medium, and two culture methods on the growth of the green alga, Enteromorpha prolifera. The relationship between the specific growth rate of E. prolifera and NO3--N concentration was consistent with that estimated using the Monod equation (R2 = 0.9713, P < 0.01). In the NO3--N medium, the maximum specific growth rate was calculated to be 0.1634/d and the semi-saturation constant was calculated to be 16.86 μmol/L. Our results show that E. prolifera can effectively utilize NH4+-N, NO3--N, and NO2--N and urea-N in the range of 5 to 50 μmol/L. NH4+-N was preferentially assimilated by E. prolifera, and urea-N was favorable for long-term growth.  相似文献   

5.
以中国生态系统研究网络CERN长武王东沟实验站的坡耕地和塬耕地为供试土壤,研究了黄土高原沟壑塬区旱耕地原状土壤氮素迁移和时空变异。结果表明:耕作土壤NO3--N为23.1~33.8 mg/kg,NH4+-N为0.23~0.50mg/kg,DOC为9.17~13.38 mg/kg,P为0.18~0.23 mg/kg;坡耕地和塬耕地的NO3--N和NH4+-N主要集中在0~20 cm的上层土壤,中下层土壤NO3--N和NH4+-N起源于上层淋溶迁移和累积;高含量时养分淋溶溶出呈指数衰减型;NO3--N、NH4+-N、DOC向下层的迁移塬耕地慢于坡耕地。  相似文献   

6.
在温度22±0.5℃、光照强度100μmol·m-2·s-1的光照培养箱中,以8组不同盐度培养半叶马尾藻(Sargassum hemiphyllum)幼苗(2~3 g/株),研究不同盐度对其生长发育和光合色素合成的影响。结果表明:半叶马尾藻幼苗适合存活和生长的盐度为24.84~35.28,在该盐度范围内幼苗均可正常存活和生长;幼苗最适生长盐度为30.06,质量增长率达到最大,光合色素含量达到最高;24.84~35.28中,幼苗更适合于在高盐端生长。  相似文献   

7.
徐闻珊瑚礁保护区营养盐时空分布特征   总被引:2,自引:1,他引:1  
2006年8月(夏季)、2006年11月(秋季)、2007年2月(冬季)和2007年4月(春季)在徐闻珊瑚礁自然保护区灯楼角至流沙湾近岸海域调查徐闻珊瑚礁保护区的营养盐变化及空间分布特征。结果表明:徐闻珊瑚礁保护区水域溶解态无机氮以NO3--N为主,其含量超过总溶解无机氮的50%;各站点NO2--N含量相对较低,冬季NO3--N和NH4+-N含量均高于其它季节;无机磷含量在0mg/L~0.030mg/L之间变化;活性硅含量表现为夏秋季节高、冬春季节低;表层水体硝酸盐氮/无机磷原子比值(N/P)夏季较低,不存在无机磷受限情况,而冬季N/P整体较高,此时水体主要受无机磷限制。  相似文献   

8.
在实验室水温26℃、盐度31条件下,研究LED蓝光(波长450 nm)不同光合光子照度对湛江等鞭金藻(Isochrysis zhanjiangensis)细胞生长速率及色素含量的影响,结果表明,不同光合光子照度的梯度实验组藻细胞生长速率及色素含量差异具统计学意义(P0.05),在66~171μmol·m~(-2)·s~(-1)范围内,细胞相对生长速率随光子照度的增加而加快,在171μmol·m~(-2)·s~(-1)时达到最大值0.48个·d~(-1),在192μmol·m~(-2)·s~(-1)时出现下降;藻细胞的7 d色素累积量在171μmol·m~(-2)·s~(-1)下其叶绿素a、叶绿素c、类胡萝卜素及总色素的累积量均达到最大,分别是3 340.16、1 176.23、1 566.43及6 082.82μg·L-1,与其他组差异具统计学意义(P0.05)。蓝光LED下湛江等鞭金藻细胞光合作用的最佳光合光子照度约为171μmol·m~(-2)·s~(-1)。  相似文献   

9.
Sediments and surface water were sampled in a tide flat in the Huiquan Bay, Qingdao, China in January 2004 to simulate the exchange of NH4-N/NO3-N/ PO 43- between sediments and surface water. A working system was designed with which samples were shaken at 60, 120 and 150 revolutions per minute (r/min). Experiment results show that NH4-N concentration in water at shaking rate of 60r/min decreased gradually, while at 120r/min increased gradually. In resuspension, fine-grained sediments contributed most NH4-N to the seawater, followed by medium-grained and coarse-grained sediments. The NO3-N concentration in water had a negative relation with the shaking rate; the medium-grained sediments contributed more NO3-N to seawater than the coarse-and fine-grained sediments. The PO 43- concentration is positively related with the shaking rate, the fine-grained sediments were the main N and P contributor to the seawater, followed by medium-and coarse-grained sediments.  相似文献   

10.
交配前雄性大鼠分别按每 kg 体质量1.25、2.50、5.00 g 的剂量灌服半叶马尾藻多糖,连续灌胃60 d,雌性大鼠分别以相同剂量连续灌胃14 d,以雄雌1∶1的比例合笼5 d,每天做阴道分泌物涂片检查,见精子者记为妊娠第1天,交配后雄鼠处死,测定血清睾酮(T)水平,取雄鼠附睾进行精子成活率、精子计数和精子畸形率测定,计算睾丸、附睾脏器比,并进行病理组织学检查;雌鼠继续灌胃至妊娠7 d,于妊娠14 d 处死,计算受孕率、着床数、黄体数、死胎、活胎和吸收胎,测定血清促卵泡生成素(FSH)、黄体生成素(LH)和雌二醇(E2)水平,计算脏器比并进行病理组织学检查.结果显示,给药组大鼠的精子成活率、精子计数、精子畸形率、受孕率、着床数、黄体数、死胎、活胎、吸收胎、睾丸、附睾和卵巢脏器比以及血清 T、FSH、LH 和 E2水平与对照组相比差异无统计学意义(P >0.05),生殖器官病理组织学检查未见明显异常.在本实验条件下,半叶马尾藻多糖对大鼠无明显生殖毒性  相似文献   

11.
Sediments and surface water were sampled in a tide flat in the Huiquan Bay, Qingdao, China in January 2004 to simulate the exchange of NH4-N/NO3-N/PO4^3- between sediments and surface water. A working system was designed with which samples were shaken at 60, 120 and 150 revolutions per minute (r/min). Experiment results show that NH4-N concentration in water at shaking rate of 60 r/min decreased gradually, while at 120 r/min increased gradually. In resuspension, fine-grained sediments contributed most NH4-N to the seawater, followed by medium-grained and coarse-grained sediments. The NO3-N concentration in water had a negative relation with the shaking rate; the medium-grained sediments contributed more NO3-N to seawater than the coarse- and fine-grained sediments. The PO4^3- concentration is positively related with the shaking rate, the fine-grained sediments were the main N and P contributor to the seawater, followed by medium- and coarse-grained sediments.  相似文献   

12.
在实验室条件下模拟多种氮源共存的虾池水环境,利用稳定同位素示踪剂,研究温度、光照、盐度、pH、藻浓度对波吉卵囊藻氨氮吸收速率的影响。结果表明:温度、光照和藻浓度对波吉卵囊藻氨氮吸收速率影响极显著(P<0.01)。当温度为20℃,照度为4 500 lx,藻浓度为5.5×105/mL,波吉卵囊藻对氨氮均有最大的吸收速率,分别为1.114、1.400、1.482μg g-1 h-1。单因素方差分析得出波吉卵囊藻吸收氨氮的最优组合为:温度20℃,照度4 500lx,盐度15,pH 7.5,藻浓度5.5×105/mL。可通过对环境因子的调控,提高波吉卵囊藻对水体中氨氮的吸收速率。  相似文献   

13.
Water samples were collected at 20 sites on 4 occasions in 2009(twice in May,and once in both August and November) along the Jiulong River,South China to examine how nutrient inputs from the Jiulong River could affect the nutrient status of the Xiamen Water.Samples were analyzed for nitrite(NO2-N),nitrate(NO3-N),ammonium(NH4-N),phosphate(PO4-P),silicate(SiO3-Si),salinity,and temperature,to determine the nutrient and trophic status of the river.The results indicate that nutrients are derived mainly from river runoff.NO3-N was the main form of DIN in most parts of the river.In addition,NO3-N,DIN,and SiO3-Si behave conservatively.There is a surplus of DIN and SiO3-Si in the river,and PO4-P is a limitation on phytoplankton growth.The concentration of DIN is typically above 0.60 mg/dm3,and higher than 1.00 mg/dm3in most parts of the river.The concentration of PO4-P is typically above 0.02 mg/dm3,while the concentration of SiO3-Si is higher than 1.00 mg/dm3.Between 2003 and 2008,samples were collected 3 times per year(May,August and November) at 27 sites in the Xiamen Water and analyzed for NO2-N,NO3-N,NH4-N,PO4-P,salinity,and temperature.We discovered that the Jiulong River was the key source of DIN into the Xiamen Water,but not PO4-P,indicating the reason of the N/P molar ratio imbalance in the Xiamen Water.In the future,the effects of high DIN concentrations on the phytoplankton communities and marine ecosystems of the Xiamen Water shall be studied.  相似文献   

14.
测试了由紫外线杀菌器、臭氧发生器、蛋白质分离器和生物过滤器4部分构成7种不同组合的水处理系统的水处理效果,探讨了各部分在水处理中的作用。结果表明,开启整套系统对砂滤水三次处理时,系统对NH4+-N、NO2--N、普通细菌、弧菌去除作用明显,去除率分别为41.92%、53.58%、94.59%和100%,且能明显增加水体溶解氧含量,对pH的影响不明显。  相似文献   

15.
Nutrient and eutrophication characteristics of the Dongshan Bay,South China   总被引:1,自引:0,他引:1  
We recorded NO 3-N, NO 2-N, NH 4-N, PO 4-P, SiO 3-Si, salinity, and temperature data at 10 stations in the Dongshan Bay in May, June, July, August, October, and November 2008, analyzing nutrient and eutrophication characteristics. The mean concentration of dissolved inorganic nitrogen(DIN) was 0.30–0.40 mg/dm 3; generally, NO 3-N was the main form in most areas. The mean concentrations of PO 4-P and SiO 3-Si were 0.040–0.060 mg/dm 3 and 1.00–1.50 mg/dm 3, respectively. We proved that the majority of the SiO 3-Si in the Dongshan Bay came from the Zhangjiang River, with some coming from the Bachimen Strait. DIN originated from both the Zhangjiang River and the Bachimen Strait. Most PO 4-P originated from the Bachimen Strait, and some came from the Zhangjiang River. We found that P was an overall limiting factor to the phytoplankton community in most of the Dongshan Bay, and that Si and N were in surplus. However, near the Bachimen Strait Si became a limiting factor, especially for diatoms, while P and N were in comparative surplus. We used a potential eutrophication assessment method to analyze eutrophication, and showed that the most serious eutrophication occurred near the Zhangjiang River estuary and near the Bachimen Strait. In 2008, DIN levels were four times higher than that in 1988; PO 4-P levels were threefold higher, while SiO 3-Si was approximately double. Dissolved nutrients increased between 1988 and 2008. DIN increased at the greatest rate comparing to PO 4-P and SiO 3-Si, thus the N/P and N/Si mol ratios increased. Further studies on the effects of high DIN concentrations on the phytoplankton communities and marine ecosystems of the Dongshan Bay are needed.  相似文献   

16.
The effects of varying nitrogen (N): phosphorus (P) ratios on the growth and N-uptake and assimilation of the harmful dinoflagellates Prorocentrum minimum and Prorocentrum donghaiense were examined in turbidistat culture experiments. Algal cultures were supplied with media containing PO34? in various concentrations to obtain a wide range of N:P ratios. Experiments to determine rates of N uptake and assimilation of different N sources (NO3?, NH4+, urea and glycine by P. minimum and NO3?, NH4+ by P. donghaiense) were conducted using 15N tracer techniques at each N:P ratio. The growth rates suggested nutrient limitation at both high and low N:P ratios relative to the Redfield ratio. On a diel basis, the growth of both species was regulated by the light-dark cycle, which may be a result of regulation of both light- dependent growth and light-independent nutrient uptake. Maximum growth rates of both species always occurred at the beginning of light phase. In P-rich medium (low N:P ratio), both species had higher N assimilation rates, suggesting N limitation. Low assimilation coefficients at high N:P ratios suggested P limitation of N uptake and assimilation. NO3? and NH4+ contributed more than 90% of the total N uptake of P. minimum. Reduced N sources were more quickly assimilated than NO3?. Highest average daily growth rates were recorded near an N:P ratio of 12 for both species. The N uptake rates of cultures at N:P ratios near Redfield ratio were more balanced with growth rates. The linkage between growth rates and N uptake/assimilation rates were conceptually described by the variation of cell N quota. The N:P ratios affect the N uptake and growth of Prorocentrum spp., and may regulate their bloom progression in eutrophic ecosystems.  相似文献   

17.
【目的】研究大型海藻固碳及氮磷吸收潜能。【方法】分析硇洲岛岩礁带19种生物量大于50 g·m~(-2)自然生长的大型海藻固碳量、生产力和TOC,对比分析岩礁带和距岩礁带4 km处海域海水中无机氮和无机磷含量。【结果】褐藻门有3种,生物量、固碳量和生产力最大,分别为20 498 g·m~(-2),550 762 g·a~(-1),2 466 g·m~(-2)·a~(-1);其次是红藻门有11种,生物量、固碳量和生产力分别为17 547 g·m~(-2),138 194 g·a~(-1),1 872 g·m~(-2)·a~(-1);绿藻门有5种,生物量、固碳量和生产力分别为3 064 g·m~(-2),4 827 g·a~(-1),158 g·m~(-2)·a~(-1)。受人类活动影响最小的博贺兰岛礁区域海藻生物量、固碳量和生产力均为最大。19种海藻中12种海藻TOC超过30%,分别为衫叶蕨藻Caulerpa taxifolia (M.Vahl) C. Agardh、囊状法囊藻Valonia utricularis(Roth)C. Ag.[Conterva utricularis]、网球藻Dictyosphaeria cavernosa(Forssk.) Boerg、珊瑚藻Corallina sp.、拟鸡毛菜Pterocladiella capillacea (Gmelin)Santelices et Hommersand、紫杉状海门冬Asparagopsis taxiformis (Delile)、茎刺藻Caulacanthus ustulatus (Mertens) Kütz、新角石藻Neogoniolithon sp.、叉节藻Amphiroa sp.、半叶马尾藻Sargassum hemiphyllum (Turn.) var. chinensis C. Ag.、囊藻Colpomenia sinuosa(Mert.exRoth)、羊栖菜Hizikiafusiforme(Harv.)Setch。岩礁带海水中的无机氮和无机磷含量分别在0.17~0.20mg·L~(-1)和0. 007~0. 018 mg·L~(-1)之间,距岩礁带断面4 km左右海域的4个相应站位IN和IP含量分别在0.18~0.22mg·L~(-1)和0.016~0.022mg·L~(-1)间,均略高于岩礁区相应站位。大型海藻的生物量与岩礁带无机氮和无机磷间Pearson相关系数分别为-0.248和-0.155。【结论】19种大型海藻在硇洲岛岩礁带海区生态环境下具有良好的生长适应性,固碳能力强,对氮磷具有吸收作用。  相似文献   

18.
利用2008~2011年共6个航次调查数据,对雷州半岛近岸海域关键水质环境因子进行时空分析,并采用富营养指数法对该海域水质环境进行了评价,结果表明:该海域近几年COD、PO4-P、NO2-N、NO3-N、NH4-N、石油类、叶绿素浓度等关键水质因子的均值变化范围分别为0.61~1.71 mg/L、0.01~0.04 mg/L、0.004~0.05 mg/L、0.05~0.21 mg/L、0.02~0.20 mg/L、0.01~0.60 mg/L、1.16~3.17μg/L。该海域COD、石油类污染程度较低,而PO4-P、无机氮污染程度高、污染风险大。半岛东部海域污染程度高于西部海域,尤其是湛江港、雷州湾及半岛东北海域呈高富营养化水平。  相似文献   

19.
在水温18℃±1℃和盐度27.0±0.5条件下,研究了饥饿对褐菖鮋耗氧率和排氨率的影响。结果表明:对照组的平均耗氧率为1.082 mg.g-1.h-1;饥饿组耗氧率随着饥饿时间的延长而下降,饥饿期间,褐菖鲉的平均耗氧率为0.893 mg.g-1.h-1,总体上低于对照组。排氨率随着饥饿时间的延长下降趋势呈阶段性变化:饥饿1 d、3 d后的排氨率略低于对照组但差异不显著(P>0.05);饥饿3~7 d,排氨率下降幅度变大,饥饿7d较饥饿3 d的排氨率下降了185.075%;饥饿14 d、21 d后排氨率分别为0.053 mg.g-1.h-1和0.028 mg.g-1.h-1,呈继续下降趋势,但下降幅度减缓。褐菖鮋的nO∶nN比值始小幅度上升,7 d时开始迅速上升,21 d后升高至27.754,差异显著(P<0.05)。  相似文献   

20.
The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH+4, NOˉ3, NO2ˉ as well as the total dissolved inorganic nitrogen (DIN). The results show that the effluent wastewater produced by fish aquaculture had typical eutrophication levels with an average of 34.3 μmol L-1 DIN. This level far exceeded the level IV quality of the national seawater standard and c...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号