高效硝化与反硝化功能菌株的分离筛选及其性能研究   总被引：1，自引：0，他引：1  

郭少鹏  江兴龙  王泽旭  魏金生 《海洋与湖沼》2020,51(6):1520-1529

本研究利用选择培养基从鳗鲡精养殖池和循环水水处理系统中分离筛选出二株脱氮细菌，应用16S rRNA分子生物学鉴定，确定菌株的种属。菌株NB-1属于芽孢杆菌属（Bacillus）、菌株DB-1是恶臭假单胞菌（Pseudomonas putida）。对菌株硝化及反硝化作用性能的研究结果表明：菌株NB-1具有良好的亚硝化及硝化作用性能，在投菌量为0.025%时，氨氮降解率为69.5%，亚硝酸盐氮降解率为99.2%。菌株DB-1在厌氧条件下表现出良好的反硝化作用性能，最适投菌量为0.6%，最佳C/N为12，对硝酸盐氮的降解率为94.6%，对总氮的降解率为64.0%。因此本研究筛选出的二株脱氮细菌可以广泛应用于养殖水体水质调控，具有良好的市场应用前景。  相似文献   

海洋功能区开发潜力评价研究--以江苏滨海县为例     

朱宇  王在峰  李加林  龚虹波 《海洋通报》2020,39(1):111-118

新一轮海洋功能区划修编在即,为平衡海洋资源开发利用和资源环境可持续利用的关系,开展海洋功能区开发潜力研究成为合理确定海域功能的重要依据。本文构建了海洋功能区开发潜力评价模型,从环境生态现状、资源现状、开发现状和社会经济需求四方面选取评价指标,建立海洋功能区开发潜力评价指标体系,并选取具有代表性的江苏滨海县作为研究区,以滨海县各海洋功能区为评价单元开展了实证研究。结果表明:滨海县海洋功能区总体开发潜力较高,环境生态和资源现状等自然条件较好,开发潜力大,但海域开发现状和社会经济需求等社会条件较差,影响了海洋功能区开发的技术支持与需求。  相似文献   

基于POI数据的城市用地功能识别与评价研究     

窦旺胜  王成新  薛明月  王召汉 《世界地理研究》2020,29(4):804-813

充分利用大数据开展城市用地功能识别，有助于把握城市空间结构，推动城市内部空间合理布局。POI数据是大数据时代一种较易获得且极具代表性的空间点状数据，能够有效地确定城市用地的实际功能。以济南市内五区的185126条POI数据为基础，对所得数据进行去重、纠偏、重分类，构建城市用地功能分类体系，运用频数密度、类型比例及核密度估计，识别济南市内五区城市用地功能并利用误差矩阵对识别结果进行检验。结果表明：①混合功能用地与单一功能用地呈现圈层化地域分布特征，“核心-外围”分异明显；②由内向外单一功能用地集聚趋势减弱，混合功能用地多样性降低，不同用地表现出不同的空间分布模式；③通过误差矩阵及与用地规划图中规划用地及电子地图的实际用地对比，识别总体精度为75.67%，识别结果较为准确。  相似文献   

秦山核电站邻近海域网采浮游植物群落分布及其影响因素     

陈悦  江志兵  寿鹿  朱根海  王志富  廖一波  高月鑫 《海洋通报》2018,(2):149-157

秦山核电站位于杭州湾北岸湾顶,其邻近海域受到钱塘江淡水径流和江浙沿岸流的共同影响,水体环境复杂。本研究根据2012年5月(春季)、10月(秋季)秦山核电站邻近海域15个站位网采浮游植物群落调查及理化因子测定,研究了该海域浮游植物群落结构、分布及其影响因子。同时比对历史数据,分析该海域浮游植物群落对环境变化的响应。调查共鉴定检出浮游植物5门60属139种(春季5门36属70种、秋季5门51属115种),其中硅藻42属110种(占85.3%),甲藻8属12种(占9.3%),绿藻、蓝藻和裸藻偶有检出。春季浮游植物平均丰度(1 802.62×104个/m~3)高于秋季(877.15×104个/m~3),其中琼氏圆筛藻Coscinodiscus jonesianus和中肋骨条藻Skeletoema costatum为两季优势种。聚类分析和典范对应分析表明,两季浮游植物群落差异显著,氮磷比、溶解无机氮、溶解无机磷和盐度是影响调查海域浮游植物的主要环境因子。比对历史资料得到,30年来秦山核电站邻近海域浮游植物赤潮藻种的增加和群落结构及丰度的改变受到营养盐含量及结构变化、水温升高等因素共同作用。  相似文献   

Assessment of the consecutive harmful dinoflagellate blooms during 2015 in the Izmit Bay (the Marmara Sea)     

ERG&#;L Halim Aytekin  AKSAN Serdar  &#;P&#;&#;RO&#;LU Merve 《海洋学报(英文版)》2018,37(8):91-101

A series of red tides were observed during 2015 in the Izmit Bay(the Marmara Sea) which is located in the most industrialized and populated region of Turkey. Six samplings were carried out in this area following the red tides.Nitrite-N, nitrate-N, ammonia, silica and orthophosphate concentrations were analyzed spectrophotometrically.Physicochemical conditions were measured by CTD probe. Plankton quantification was performed using counting chambers under microscopes. Prorocentrum micans was the most abundant species, except on May 14,2015, when Noctiluca scintillans was dominant. The abundance of P. micans reached average 18×10~6 ind./L on May 3, 2015 in the Karamürsel station, simultaneously with elevated levels of NH_3 and o-PO_4~(3–). The sample was also abundant in dead amphipods((72±12) ind./L) that had been covered by mucilage aggregates produced by P.micans. The highest biomass(calculated by carbon) was recorded as(268±26.0) mg/L on May 14 in the Hereke station. Beside the anthropogenic wastewater discharges, unknown sources and resuspensions caused increases in nutrient levels. After long term northeaster gusts(35 km/h for 5 d) an upwelling occurred on November 6, 2015 after wind-induced sediment resuspension. Although nutrient discharges remarkably decreased over 30 years through established wastewater treatment plants, harmful phytoplankton blooms still occur. Comparing the present results with other studies in nearby Mediterranean seas reveals that the most intense harmful dinoflagellate bloom in recent years occurred in the Izmit Bay. Therefore, additional protection measures necessary for a cleaner Izmit Bay. These incidents also demonstrate that contaminants, accumulated in sediment,may have long-lasting effects on enclosed marine ecosystems.  相似文献   

印尼爪哇上升流海域次表层叶绿素最大值层的浮游植物色素分布特征     

高春蕾  傅明珠  宋洪军  王磊  韦钦胜  孙萍  刘琳  张学雷 《海洋学报(英文版)》2018,37(12):97-106

Upwelling occurs on the coast of Java between June and October, forced by local alongshore winds associated with the southeasterly monsoon. This causes variations in phytoplankton community composition in the upwelling zone compared with the surrounding offshore area. Based on pigments analysis with subsequent calculations of group contributions to total chlorophyll a(Chl a) using CHEMTAX, we studied the distribution and composition of phytoplankton assemblages in the subsurface chlorophyll maximum along the south coast of Java and the influence of upwelling. Nineteen phytoplankton pigments were identified using high-performance liquid chromatography, and CHEMTAX analysis associated these to ten major phytoplankton groups. The phytoplankton community in the coastal area influenced by upwelling was characterized by high Chl a and fucoxanthin concentrations, indicating the dominance of diatoms. In contrast, in the offshore area, the Chl a and fucoxanthin concentrations declined to very low levels and the community was dominated by haptophytes represented by 19′-Hexanoyloxyfucoxanthin. Accordingly, microphytoplankton was found to be the major size class in the coastal area influenced by upwelling, while nanophytoplankton was most abundant in the offshore area. Low concentrations of other accessory pigments indicated less contribution from dinoflagellates,prasinophytes, chlorophytes and cryptophytes. Photo-pigment indices revealed that photosynthetic carotenoids(PSCs) were the largest component of the pigment pool, exceeding the proportion of Chl a, with the average PSCTP up to 0.62. These distribution trends can mainly be explained by phytoplankton adaption strategies to upwelling and subsurface conditions by changing species composition and adjusting the pigment pool.  相似文献   

Different levels of macroalgal sampling resolution for pollution assessment     

Isabel Díez  Alberto Santolaria  José María Gorostiaga 《Marine pollution bulletin》2010,60(10):1779-1789

The effects of using reduced sampling resolutions to study macroalgal vegetation patterns have not been studied sufficiently. Here, we test the influence of taxonomic resolution level, removal of occasional species, aggregation of species abundances into functional groups and data transformation in the detection of a long-term recovery process by phytobenthic intertidal assemblages. Results indicate that the aggregation of species data into the genus level has very little influence. Likewise, almost any significant information is lost when occasional algae are removed. Analyses at the level of families and orders still clearly detect differences between highly degraded and reference vegetation. By contrast, analyses based on class and functional group abundances capture quite different information. The effect of transformation is similar at the different taxonomic levels. Most surrogate measures properly reflect changes in diversity. It is concluded that genus level is the most appropriate surrogate approach for detecting the recovery process.  相似文献   

非Dedekind完备的序拓扑向量空间中集值映射的一类扩张     

肖赟  刘信东 《成都信息工程学院学报》2010,(6):336-340

在泛函分析中有着重要作用的Hahn-Banach扩张定理及其很多推广定理的条件都要求值域空间是Dedekind完备的,这是一个非常强的条件,因而在一定程度上局限了这些扩张定理的应用。主要考虑弱化这些定理的条件,讨论当值域空间是由锥引人序的非Dedekind完备的序拓扑向量空间时,一类集值映射的扩张。  相似文献   

近30年天津滨海新区湿地景观格局遥感监测分析   总被引：6，自引：0，他引：6  

孟伟庆  李洪远  郝翠  莫训强 《地球信息科学学报》2010,12(3):436-443

在GIS和FRAGSTATS软件支持下,结合景观格局数量分析方法,利用1979-2008年间共6期TM遥感影像与非遥感数据,对天津滨海新区近30年的湿地景观空间格局进行了动态分析。结果表明,滨海新区湿地(以人工湿地为主),1979-2004年滨海新区湿地总面积变化不大,但各类型间转换较大,主要是自然湿地转变为人工湿地,沼泽湿地几近消失。2006-2008年,由于城市建设大量滨海滩涂湿地被围填占用,到2009年5月自然海岸线的90%以上被占用。景观破碎度增加,湿地斑块数量从137个增加到704个,同时造成平均斑块面积下降。驱动力分析表明,降雨量减少的同时,年平均气温上升是主要的自然驱动因素。和自然因素相比,人类干扰为主要人文驱动因素,表现在水产养殖为主的农业经济活动、城市建设用地占用和围海造地等方面。目前,滨海新区几乎没有自然湿地生态系统,破碎化和人工化是该区域湿地的主要特征。  相似文献   

水平层状介质中双侧向测井资料的迭代Tikhonov正则化反演   总被引：2，自引：0，他引：2       下载免费PDF全文

姚东华  汪宏年  陶宏根  杨守文 《地球物理学报》2010,53(9):2227-2236

根据非线性反演理论与Morozov偏差原理研究建立从双侧向测井(DLL)资料中同时重构地层原状电阻率、侵入带电阻率、侵入半径、层界面位置以及井眼泥浆电阻率的迭代正则化算法.首先利用Tikhonov正则化反演理论将双侧向测井资料的反演问题转化为含有稳定泛函的非线性目标函数的极小化问题,并利用Gauss-Newton算法确定极小化解.为得到稳定的反演结果并有效实现测井资料的最佳拟合,在迭代过程中将Morozov偏差原理和Cholesky分解技术相结合,建立了一套后验选择正则化因子的方法.最后通过理论模型和大庆油田实际测井资料的处理结果,验证了该算法能够取得更为满意的反演效果.  相似文献