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1.
太湖氮磷浓度与水质因子的关系   总被引:6,自引:2,他引:4       下载免费PDF全文
在2003年10月27、28日和2004年8月19日的太湖水质试验数据基础上,研究与探讨了氮浓度、磷浓度与叶绿素a浓度、悬浮物浓度和CDOM(Colored Dissolved Organic Matter)浓度之间的定量关系。研究结果表明:①在2003年10月份和2004年8月份,太湖梅梁湾地区水体的氮、磷浓度介于1~4mg/L和0.1~0.3mg/L,该浓度恰好处于易发生水华的营养物质浓度供应区间;②与2004年8月19日相比,2003年10月27、28日的太湖藻类处于低增长、高消亡状态;③在太湖梅梁湾地区,氮、磷浓度与CDOM浓度、叶绿素a浓度和悬浮物浓度之间存在较强的线性相关性,其相关系数大于0.557;④在太湖水体中,磷浓度、CDOM浓度、叶绿素a浓度和悬浮物浓度的四因子关系模型比氮浓度、CDOM浓度、叶绿素a浓度和悬浮物浓度的四因子关系模型的相关系数高。  相似文献   

2.
2013年6月至2014年5月逐月对洞庭湖水体叶绿素a质量浓度和主要环境因子进行测定,分析洞庭湖水体叶绿素a质量浓度的时空分布特征,探讨洞庭湖水体叶绿素a质量浓度与环境因子的相关性。结果表明,洞庭湖水体叶绿素a质量浓度为0.11~8.62 mg/m~3,年均值为(1.89±1.23)mg/m~3,属贫营养;叶绿素a质量浓度随季节变化明显,总体呈现夏、秋季明显大于冬、春季的规律;在空间上,总体表现为西洞庭湖和东洞庭湖明显大于南洞庭湖。全湖叶绿素a质量浓度与水温、电导率、COD和TP呈极显著正相关,与DO、NH3-N、TN和TN/TP呈极显著负相关,与NO-3-N呈显著负相关,与p H和透明度无显著相关性。全湖TN/TP的年均值为28.5,磷可能是洞庭湖水体浮游植物生长的限制性营养盐。  相似文献   

3.
利用遥感数据处理软件SNAP中基于神经网络技术的C2RCC算法,对2019年5月9日南黄海“哨兵3号”卫星OLCI影像数据进行了叶绿素a及总悬浮物浓度反演,将其与5月间江苏省海洋环境监测预报中心的海水表层叶绿素a和悬浮物实测数据进行了比较分析。结果表明,叶绿素a的遥感反演尚未能达到业务化应用,总悬浮物遥感反演结果的空间分布与实测值的一致性相对较好。但在星地同日或相差一天监测的南通海域,遥感反演叶绿素a浓度的空间分布趋势以及总悬浮物遥感反演结果与海面实测结果的一致性较好,可达到一定的业务化应用效果。  相似文献   

4.
基于Landsat-5 TM数据和地面同步水质监测数据发现,近红外波段与红色波段比值与叶绿素a实测浓度存在较高相关性,并以此建立了提取水体表层叶绿素a浓度的遥感信息模型。经验证,该模型用于叶绿素a浓度反演的精度良好,平均相对误差为14.5%。将该模型应用于Landsat卫星系列数据,提取了东平湖1985-2015年每年度丰水期叶绿素a浓度信息,得到共31幅东平湖叶绿素a浓度分布图,并对其进行了时空分析。结果表明:1985-2015年,东平湖叶绿素a平均浓度范围为32.4~81.4 μg/L,空间分布上一般表现为湖周边浅水区高于湖中心深水区,且空间差异变化明显;时间序列上,东平湖叶绿素a浓度表现出一定的波动性,在1987、1988、1992年出现较高值,总体看来,在95%置信水平上秩相关系数为-0.592,浓度呈下降趋势。  相似文献   

5.
基于2013-2021年渤海遥感反射率和叶绿素a浓度等实测数据,开展了该海域MODIS影像的叶绿素a浓度遥感反演模型研究。选择OC3经典模型形式,采用渤海的实测数据进行拟合分析,获取了适用于渤海的模型局地化参数,通过真实性检验得到叶绿素a浓度的遥感反演结果与实测值的决定系数为0.84,平均相对误差为24.77%,均方根误差为5.56 μg/L,反演精度较佳。利用该算法反演获取了渤海2002-2021年叶绿素a的月度、季度和年度平均浓度,分析了其时空变化特征,同时结合2001-2021年渤海非优良水质比例开展了环境响应分析。分析结果显示:2001-2021年,渤海非优良水质比例与同时期叶绿素a浓度变化趋势基本一致,呈现先变差后变好的倒V形趋势;5年平均的非优良水质比例与叶绿素a浓度变化趋势更直观地反映了2001-2021年渤海整体的水环境变化趋势,与非优良水质比例相比,叶绿素a浓度对渤海水环境的改善响应更快。  相似文献   

6.
利用海州湾海域2004~2006年的水质监测资料,选择同期成像质量良好的MODIS Terra 1B影像,分别在单波段因子和波段组合与叶绿素a浓度之间进行相关分析,发现近红外波段和绿波段、红波段的比值因子、差值因子以及仿植被指数因子与叶绿素a浓度相关性较高.用这些因子建立叶绿素a浓度的回归模型,其中因子F7(24)的二次多项式模型的R2达到0.801,平均相对精度达到65%以上,且模型具有较高的泛化能力,不仅证明了利用MODIS 1B影像监测海面叶绿素a浓度的可行性,而且对于监测该海域赤潮和富营养化状况具有重要的现实意义.  相似文献   

7.
山仔水库叶绿素a与环境因子的相关分析及富营养化评价   总被引:22,自引:0,他引:22  
依据2003年3~11月对山仔水库的逐月调查和监测数据,分析叶绿素a含量的时空分布情况,探讨叶绿素a与相关环境因子的关系,并应用修正的卡尔森营养状态指数对山仔水库水质进行分析评价。结果表明,山仔水库除了3、10、11月份处于中营养状态,其余月份都处于富营养化状态。叶绿素a具有明显的时空分布特征。日溪进口和山仔水库坝前的叶绿素a含量较高;初夏和秋末出现高峰,叶绿素a含量分别高达211 mg/m^3和93mg/m^3。多元统计分析表明,与山仔水库叶绿素a含量显著相关的因子是水温和溶解氧。生物因子评价表明,山仔水库浮游藻类的种类和数量都达到了富营养化水平。  相似文献   

8.
建立了绿藻中叶绿素a的导数同步荧光检测法。该方法快速、简便,不需要复杂的前处理。叶绿素a的线性范围为0.02~125μg/L,检出限为0.25μg/L,回收率为97.0%~103.8%。  相似文献   

9.
选用废弃矿山绿化常用的禾本科、豆科、葡萄科和紫葳科共17种为实验材料,测定了其叶绿素各组分含量及超氧岐化酶(SOD)和过氧化物酶(POD)活力,结果表明:叶绿素a、b类胡萝卜素和叶片色素总质量比最高的植物分别是胡枝子、狗牙根、牧草型狗牙根和狗牙根,其质量比分别为2.46 mg/g.FW、1.10 mg/g.FW、0.32 mg/g.FW和3.63 mg/g.FW;4者质量比最低的是紫穗槐、三出叶爬山虎、芒和紫穗槐,为1.10 mg/g.FW、0.48 mg/g.FW、0.08 mg/g.FW和1.70 mg/g.FW。ωa(叶绿素a)/ωb(叶绿素b)最高的是牧草型狗牙根,为3.03 mg/g.FW,最低的是芒,仅为1.65 mg/g.FW。POD和SOD活力最高的是网络崖豆藤和芒,达477.00 U和217.20 U,最低的是牧草型狗牙根和紫穗槐,仅为24 U和39.43 U。  相似文献   

10.
叶绿素a浓度是反映湖泊富营养化状态的一个重要参数。以MODIS L1B数据为基础,结合叶绿素a浓度实测数据,基于经验分析法实现了西藏典型湖泊叶绿素a浓度反演研究,并探索了西藏典型湖泊2019年春、夏、秋季叶绿素a浓度的时空变化特征。首先,利用叶绿素a浓度实测数据和MODIS L1B影像不同波段的反射率值进行组合试验,选择最佳波段组合建立模型;其次,分别选用2015年、2017年叶绿素a浓度实测值和反演值对模型进行对比验证;最后,利用叶绿素a浓度反演模型对西藏典型湖泊2019年春、夏、秋季叶绿素a浓度的时空变化特征进行分析。结果表明:在空间尺度上,西藏典型湖泊叶绿素a浓度整体上呈现出周围高、中部低的分布特征,且湖岸水体叶绿素a浓度变化较大;在季节尺度上,不同湖泊叶绿素a浓度的季节变化存在较大差异,格仁错和色林错的季节变化幅度较大,纳木错、塔若错和羊卓雍错的季节变化幅度较小。  相似文献   

11.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

12.
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.  相似文献   

13.
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).  相似文献   

14.
土壤和底泥中砷、铬、锰测定的前处理技术   总被引:6,自引:0,他引:6  
试验了土壤和底泥中砷的前处理技术,其目的是能对土壤、底泥中砷、铬、锰在一次前处理中制备成试液,比色法分析。试验表明,用H2SO4-H3PO4-H2O2进行前处理是可行的。方法简单、挥发酸雾少,用标准参考物质检验证明,分解完全,数据准确,有粒较好一致性。  相似文献   

15.
This paper presents the chemical speciation and retention behavior of chromium (Cr), nickel (Ni), and cadmium (Cd) prior to and after the electrokinetic remediation in glacial till soil. The speciation of the metals was predicted using the chemical speciation program MINEQL+. The simulations were performed for single-contaminant with only Cr(VI) or Ni, and multi-contaminants consisting of: (1) Cr(VI), Ni, and Cd; (2) Cr(III), Ni and Cd; (3) Cr(VI), Cr(III), Ni and Cd; (4) Cr(VI), Ni, and Cd with reducing agents; and (5) Cr(III), Ni, and Cd with oxidizing agent (Mn). The results showed that the speciation and distribution of cationic metals [Ni, Cd, and Cr(III)] in glacial till soil remain unaffected or slightly affected during electrokinetics. This is attributed to the high pH buffering capacity of the glacial till, leading the metals to precipitate in the soil prior to and after electrokinetics. This study showed that during electrokinetics, Cr(VI) existed as anionic complex and migrated towards the anode and the migration is maximum in case of a single-contaminant system. The study also showed that near the anode in the absence of any reducing and oxidizing agent, Cr(VI) mostly adsorbed, and some of Cr(VI) reduced to Cr(III) and migrated towards the cathode and finally precipitated due to high pH conditions. Ni and Cd remain adsorbed or precipitated due to the high pH conditions throughout the soil. Among the reducing agents, the sulfide had significant effect on the migration of metals compared to ferrous ions. While in the presence of oxidizing agent (Mn), no noticeable Cr(VI) was found in the soil sample indicating the reduction of Cr(VI) to Cr(III) and the predominance of reducing conditions due to the presence of naturally occurring iron in the glacial till soil. Overall, this study provides a reasonable explanation of the speciation and distribution of chromium, nickel and cadmium during the electrokinetic remediation of glacial till soil.  相似文献   

16.
We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60-times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies.  相似文献   

17.
18.
The present study demonstrates comparison of Cr accumulatingpotential by the plants of Najas indica Cham. (submerged),Vallisneria spiralis L. (rooted submerged) and Alternanthera sessilis R. Br. (rooted emergent) under repeatedmetal exposure and its effect on chlorophyll and protein concentrations. These plants were treated with different concentrations of Cr under repeated exposure in controlled laboratory conditions to assess the maximum metal accumulationpotential. The plants of V. spiralis accumulated significantly high amount of Cr under laboratory conditions incomparison to N. indica and A. sessilis. The maximumaccumulation of 1378, 458 and 201 g g-1 dw Cr was found in the leaves of V. spiralis, N. indica and A. sessilis, respectively at 8 mg L-1 after 9 day of Cr exposure. These plants have shown a decrease in chlorophyll andprotein concentrations with increase in Cr concentrations. In view of high accumulation of Cr in V. spiralis, the plantswere treated with different concentrations of tannery effluent collected from Common Effluent Treatment Plant, Unnao (UP). Theplants of V. spiralis treated with 100% tannery wastewatershowed the maximum accumulation (57.5 g g-1 dw) of Cr in the roots after 10 days of exposure. The plants were foundeffective in removing Cr from solution and tannery effluent.  相似文献   

19.
一起河流砷污染事故的处置与监测分析   总被引:2,自引:1,他引:1  
介绍了大沙河砷污染事故的处置和监测分析。多介质排查监测摸清了污染的范围和程度,为治理工作提供了科学依据,污染治理措施有效控制了污染的扩散;监测数据表明,治理措施将水中砷污染物沉降至河床使污染水质达标排放。吸附了大量砷化合物的底泥被清理并进一步处置,多介质跟踪监测应持续进行直至不存在潜在危害。  相似文献   

20.
日本核泄漏事故引发的核危机为人类安全和平地利用核能又一次敲响了警钟.核事故应急工作作为减小核电站危害环境和公众安全的最后屏障,将起到重要的作用,必须做好相关的准备和响应工作.核应急辐射环境监测工作是核应急工作的重要组成部分,在对核应急辐射环境监测进行准备和响应时主要遵循实用性、适用性和适度性并兼顾常规和应急监测的“平战...  相似文献   

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