The Influences of Mg^2 ,Ca^2 ,and Mg^2 /Ca^2 Ratio in Mixed Seawater on the Emergence Rate of Penaeus Japonicus Postlarva

This paper reports the approprite ranges of Mg^2 ,Ca^2 and their ratio Mg^2 /Ca^2 in mixed seawater for rearing of Penaeus japonicus larvae,The ranges for the above three indices are 1150-1450mg/L,360-440mg/L and 2.8-3.4,respectively,the proper salinity range of mixed seawater is 22.1-33.9 obtained by mixing estuarine water and concentrated seawater.     

Removal of K^＋, Na^＋, Ca^2＋, and M^g2＋ from saline-alkaline water using the microalga Scenedesmus obliquus

The capability ofScenedesmus obliquus to remove cations （K^＋, Na^＋, Ca^2＋, Mg^2＋） from saline- alkaline water was investigated at different salinities （0, 5, 10, 15, 20, 25） and carbonate alkalinities （0, 5, 10, 15, 20, 25, 30, 35 mmol/L）. K^＋, Na^＋, Ca^2＋, and Mg^2＋ in saline-alkaline water were efficiently removed by S. obliquus. The maximum removal of the cations （29.37 mg for K^＋, 185.85 mg for Na^＋, 23.07 mg for Ca^2＋, 66.14 mg for Mg^2＋） occurred at salinity 25. The maximum removal of K^＋ （2.28 mg）, Na＋ （6.62 mg）, Ca^2＋ （1.01 mg）, and Mg2＋ （0.62 mg） occurred at carbonate alkalinities of 25 mmol/L for K＊, 35 mmol/L for Na＋, 20 mmol/L for Ca2＋, and 25 mmol/L for Mf＋, respectively. Under a salinity stress, the concentration of Na＇ in S. obliquus increased significantly, while that of K~ decreased significantly. The concentrations of Ca^2＋ and Mg2＋ decreased as well. The ratios of K＋/Na~, Ca2＋/Na^＋, and Mg^2＋/Na^＋ were significantly lower in all salinity treatments than those of the control. Under alkaline stress, the concentrations of Nan and K＋ in S. obliquus decreased significantly and the ratios of K^＋/Na^＋, Ca2＋/Na^＋, and Mg^2＋/Na^＋ were significantly higher in all treatments than in the control. Moreover, the concentrations of Ca2＋ and Mg2＋ in S. obliquus at alkalinities of 5-10 mmol/L were significantly higher than those of the other treatments. The removal of Na＋ by S. obliquus mainly occurs through biosorption, and Mg^2＋ and Ca^2 ＋ were removed through both biosorption and bioaccumulation.     

The influence of Fe^2＋ on growth and development of cells enzymatically isolated from Porphyra yezoensis blades

Fe^2＋ acted as an accessorial factor for many cellular enzymatic reactions is very important for seaweed growth and development, but the Fe^2＋ requirement in nori had not been seen. Porphyra yezoensis cells were separated enzymatically and cultured in a series of sterilized seawater media containing various concentrations of Fe^2＋. The growth development and cell were investigated in this work. Through this experiment, two biologically-meant concentration scales were found, one is low concentrations, 12.1-102.1μg/L, 10-100 times than that in seawater, favoring the development of isolated cells of Porphyra and the other was high concentrations, more than 10mg/L inhibiting the cell growth, leading to the deformity and shrinkage of the cells. At the concentration of 50 mg/L, the cells stopped growing and died eventually.     

新疆阿克苏典型山前洪积扇内高氟地下水的化学特征及氟富集机制

在内陆干旱区,作为重要饮用水源的地下水常面临氟含量超标问题。查明内陆干旱区高氟地下水的分布规律,了解氟在地下水中的富集过程及其影响因素,既可丰富高氟地下水的研究体系,也是保证内陆干旱区饮水安全的重要基础。以新疆阿克苏地区典型山前洪积扇——依格齐艾肯河-喀拉玉尔滚河河间地带为研究区,基于水文地球化学调查结果,刻画了高氟地下水的分布区;结合氟离子含量与特征性水化学指标间的关系,揭示了高氟地下水的成因机制。结果表明:①地下水中氟含量的变化范围为0.8~6.1 mg/L,83%的水样氟含量超过《生活饮用水卫生标准》（GB 5749-2006）规定的上限（1.0 mg/L）;②总体上,氟含量沿地下水流动路径逐渐增大,低氟地下水（ρ（F-）≤1.0 mg/L）分布在国道314以北的补给区,高氟地下水（ρ（F-）>1.0 mg/L）分布在国道314以南的径流区和排泄区;③高氟地下水的水化学类型以Cl·HCO₃-Na型为主,而低氟地下水则以Cl·SO₄-Na型为主,高氟地下水相比于低氟地下水优势阴离子偏向于HCO₃-;④地下水的pH值范围为7.9~8.9（均值为8.4）,表明其处于弱碱环境中。地下水中ρ（F-）与pH值呈正相关,此外构成浅层含水层的上更新统沉积物中含有黑云母、氟磷灰石等矿物,其表面存在一定数量的可交换F-,这表明水中OH-与矿物表面F-间的阴离子交换可能对氟的富集有一定贡献;⑤地下水的F-含量与Ca2+含量呈负相关,即高氟地下水中ρ（Ca2+）小于低氟地下水。考虑到氟化钙（CaF₂）是自然界中的主要含氟矿物,也是地下水中氟的主要来源,ρ（F-）与ρ（Ca2+）间的这种负相关指示着高氟地下水中可能存在去Ca2+、Mg2+作用,如阳离子交替吸附或碳酸盐岩沉淀等。研究区地下水样中ρ（F-）与ρ（Mg2+）间也呈负相关关系,且和ρ（F-）与ρ（Ca2+）间的关系高度相似,也佐证了高氟地下水中去Ca2+、Mg2+作用的存在;⑥绝大部分地下水样品都位于氯碱性指数图的负值区域,且ρ（F-）与CAI-1和CAI-2均呈较好负相关,CAI-1和CAI-2都随ρ（F-）的增大而减小,这表明高氟地下水中存在Ca2+、Mg2+与Na+间更强的交换作用,对氟富集起着重要作用。地下水中ρ（F-）与SAR间呈较好正相关关系,且高氟地下水样的SAR均值（5.71）远大于低氟地下水SAR均值（1.67）,这也进一步证明高氟地下水中的Ca2+、Mg2+与含水介质的Na+间存在强烈的交替作用,对氟的富集起着重要作用;⑦所有地下水样中的萤石均处于未饱和状态,且萤石的饱和指数（SI）与F-含量间呈现较好的正相关,这表明地下水对含氟矿物（主要是萤石）的持续溶解应是导致研究区地下水中氟富集的主要原因。与之相反,研究区所有地下水样中的方解石均处于过饱和状态（SI>0）。这表明CaCO₃的沉淀可能促进了CaF₂的溶解,导致地下水中氟离子质量浓度增高;⑧研究区低氟地下水的δ18O值介于-11.20‰~-10.67‰间,平均值为-10.94‰,而高氟地下水的δ18O值介于-11.65‰~-11.21‰间,平均值为-11.49‰,即低氟地下水较高氟地下水富集δ18O。此外,F-质量浓度较低（ρ（F-）≤3.0 mg/L）的地下水样中δ18O值与F-质量浓度呈负相关,即低氟地下水具有更正的δ18O值;F-质量浓度较高（ρ（F-）≥4.8 mg/L）的地下水样中δ18O值与F-质量浓度的相关性不显著,随F-质量浓度的增高,δ18O值基本维持不变。以上表明蒸发浓缩作用对地下水中氟的富集贡献较小;⑨研究区地下水中ρ（F-）/ρ（Cl-）比值与ρ（F-）间呈现正相关,即ρ（F-）/ρ（Cl-）比值随ρ（F-）增高呈增大趋势,这也说明地下水中氟富集的主要原因是含氟矿物的溶解,而不是蒸发浓缩作用。此外,Gibbs图也提供了证据:研究区地下水样基本处于水岩作用主导区域,表明地下水化学特征（包括氟的富集）主要受水岩作用控制,蒸发浓缩影响很小。总之,地下水中氟的富集主要由溶解作用引起,OH-与矿物表面F-间的交换也有贡献,但蒸发浓缩作用影响微弱。含氟矿物持续溶解的驱动机制是阳离子交替吸附（地下水中Ca2+与岩土颗粒表面Na+之间）及方解石沉淀所引起的地下水中Ca2+的衰减。      

宜昌长江南岸岩溶地下水中水生动物群落分布特征及其环境响应

为探究宜昌长江南岸岩溶区地下水中水生动物群落分布特征及环境响应规律,在2018年7月至8月对宜昌长江南岸15处表层岩溶泉及9处岩溶大泉中水生动物进行采集,同时对地下水理化指标进行测试。共采集到809个动物个体,共有13个亚纲,同时包括多个物种的暗层和非暗层种。结果发现:①不同动物在地下水空间分布上各异,在表层岩溶泉,Copepoda的暗层种和Ostracoda的暗层种大量存在(31.3%, 23.7%),Trichoptera和Diptera少量存在(0.4%, 2.9%);在岩溶大泉,Copepoda(非暗层种)和Amphipoda大量存在(25.0%, 8.3%),Ostracoda的暗层种少量存在(2.2%)。②不同地下水的环境也表现出差异,区内岩溶大泉pH, Na+, Ca2+, Mg2+等指标的极差(分别为0.64, 1.25, 34.0, 22.1 mg/L)小于表层岩溶泉(分别为2.45, 5.68, 59.6, 33.4 mg/L),表现出更稳定的环境特征。③通过对各环境因子以及不同物种的逐步回归分析得出,表层岩溶泉的主控环境因子为pH, Na+, Mg2+,岩溶大泉的主控环境因子为pH, SO₄2-, Mg2+;表层岩溶泉的主要代表性生物群落为Ostracoda, Diptera, Turbellaria的暗层物种,岩溶大泉的主要代表性生物群落为Mollusca, Diptera, Decapoda。④通过路径分析发现,生物通过种间相互作用,对环境因子具有直接与间接响应。在表层岩溶泉,Diptera主要通过与Ostracoda的种间关系对Na+和Mg2+起间接响应,另外Ostracoda, Diptera, Turbellaria的暗层种对pH有直接响应;在岩溶大泉,Mollusca主要通过Diptera对pH起间接响应,Diptera通过Decapoda对SO₄2-起间接响应,另Mollusca, Diptera, Decapoda对Mg2+直接响应。研究发现生物分布规律是对于环境因子的直接作用和生物之间的间接作用共同响应结果。      

Mg2+、Mn2+对波吉卵囊藻生长的影响

【目的】研究Mg²⁺、Mn²⁺对波吉卵囊藻生长和多糖代谢的影响。【方法】取蒸馏水培养数日后的波吉卵囊藻液接入以f/2培养液的配方为基础的新鲜培养液中,Mg²⁺浓度梯度分别设置为0、1、2、4、8 mg/L,Mn²⁺浓度梯度分别设置为0、0.005、0.050、0.500、5.000 mg/L,实验周期为10 d。【结果与结论】不同浓度Mg²⁺、Mn²⁺对波吉卵囊藻的生长有显著性影响,当Mg²⁺质量浓度为2 mg/L时,波吉卵囊藻的相对增长率、色素蛋白含量均出现最大值,显著高于Mg²⁺添加量为0、4和8 mg/L的组(P<0.05),当Mn²⁺质量浓度为0.005 mg/L时,波吉卵囊藻相对增长率、色素蛋白含量均出现最大值,显著高于Mn²⁺添加量0、0.050、0.500和5.000 mg/L组(P<0.05)。不同浓度Mg²⁺、Mn²⁺对波吉卵囊藻胞外多糖含量有显著影响(P<0.05),当Mg²⁺质量浓度>2 mg/L、Mn²⁺质量浓度>0.005 mg/L时,波吉卵囊藻生长均受到胁迫,其胞外多糖合成量明显增加,以保护藻体不受危害;当Mg²⁺质量浓度为8 mg/L、Mn²⁺质量浓度为5.000 mg/L时,波吉卵囊藻胞外多糖含量分别为对照组的2.43和3.36倍。     

Dynamics and Relationships of Ca,Mg,Fe in Litter,Soil Fauna and Soil in Pinus koraiensis-Broadleaf Mixed Forest

The Liangshui Natural Reserve in Heilongjiang Province of China was selected as the study area.The authors collected the samples of forest litter (Tilia amurensis,Fraxinus mandshurica,Pinus koraiensis,Acer mono,Betula costata,and mixed litter),soil in humus horizon (0-5cm) and soil horizon (5-20cm),and soil macrofauna (Oligochaeta,Geophiloporpha and Juliformia) from 2001 to 2002.The role of soil macrofauna in the material cycle was analyzed through comparing the macro-element contents among various parts of the subsystems and using enrichment index (EI).The results indicate that dynamic changes of various litters are very complicated.The contents of Fe in each kind of litter increase firstly,and then decrease in the study period.The changes of macro-element contents are greater in the broad-leaf litter than in the coniferous litter,and the mixed litter is in the middle level,but the differences among them are not significant.The contents of Mg and Fe in humus are higher than those in soil,but the contents of Ca in soil are higher than that in humus.The dynamic changes of macro-element contents in soil and soil fauna are not consistent with those in litter.The diplopod presented obvious enrichment of Ca and Mg (EI>1),but it does not significantly enrich Fe.Earthworm has a stronger enrichment ability of Fe than diplopod and scolopendra,but EI<1.Soil fauna can make great influences on the material cycle of the subsystems.     

Determination of Ca,K, Mg and Fe in four fish species by FAAS

A method for determining calcium(Ca),potassium(K),magnesium(Mg) and iron(Fe) in four fish species was optimized and validated.It included microwave mineralization of the samples and subsequent quantification by flame atomic absorption spectroscopy(FAAS) with Zeeman-effect background correction.Using HNO3(65%) and H2O2(33%) as extraction solutions,the optimal conditions of extraction were established as follows:0.5 g of sample mass;microwave time program of 300 W/5 min and 600 W/5 min.The method was free of matrix interferences.The linear correlation coefficients were ≥0.9991,the recovery percentage of analytes was from 99.31% to 103.70% and the RSD(relative standard deviation) was lower than 2.06%.The detection limits obtained were 32.3,43.2,14.0 and 68.6 ng mL-1 for Ca,K,Mg and Fe in FAAS respectively.It is shown that the method is rapid,simple,sensitive and accurate.The method was applied to the studies of digestibility and measurement of these nutrients in samples of fish collected from Norway,Japan and China.     

Genesis of underground brine along south coast of Laizhou Bay： hydrochemical characteristics

1 INTRODUCTION Two large-scale concentration mechanisms, evaporation and freezing, have been proposed for marine origin brine production (Bein and Arad, 1992; Bottomley et al., 1999). There are three basic requirements for brine formation by seawater evap…     

Effects of heavy metals (Pb2+ and Cd2+) on the ultrastructure, growth and pigment contents of the unicellular cyanobacterium Synechocystis sp. PCC 6803

The unicellular cyanobacterium Synechocystis sp. PCC 6803, a model organism known for its unique combination of highly desirable molecular genetic, physiological and morphological characteristics, was employed in the present study. The species was cultured in BG11 liquid medium contained various initial concentrations of Pb2+ and Cd2+ (0, 0.5, 1, 2, 4, 6 and 8 mg/L). The experiment was conducted for six days and the metal induced alterations in the ultrastructure, growth and pigment contents were assessed. Alterations in the ultrastructure of the Synechocystis sp. PCC 6803 ceils became evident with the increased (>4 mg/L Pb2+) metal concentration. The photosynthetic apparatus (thylakoid membranes) were found to be the worst affected. Deteriorated or completely destroyed thylakoid membranes have made large empty spaces in the cell interior. In addition, at the highest concentration (8 mg/L pb2+), the polyphosphate granules became more prominent both in size and number. Despite the initial slight stimulations (0.2, 3.8 and 6.5% respectively at 0.5, 1 and 2 mg/L Pb2+), both metals inhibited the growth in a dose-dependent manner as incubation progressed. Pigment contents (chlorophyll a, βcarotene and phycocyanin) were also decreased with increasing metal concentration. Cells exposed to 6 mg/L Pb2+, resulted in 36.56, 37.39 and 29.34% reductions of chlorophyll a, β carotene and phycocyanin respectively over the control. Corresponding reductions for the same Cd2+concentrations were 57.83, 48.94 and 56.90%. Lethal concentration (96 h LC50) values (3.47 mg/L Cd2+ and 12.11 mg/L Pb2+) indicated that Synechocystis sp. PCC 6803 is more vulnerable to Cd2+ than Pb2+.     

Effects of heavy metals （Pb^2＋ and Cd^2＋） on the ultrastructure, growth and pigment contents of the unicellular cyanobacterium Synechocystis sp. PCC 6803

The unicellular cyanobacterium Synechocystis sp. PCC 6803, a model organism known for its unique combination of highly desirable molecular genetic, physiological and morphological characteristics, was employed in the present study. The species was cultured in BG11 liquid medium contained various initial concentrations of Pb²⁺ and Cd²⁺ (0, 0.5, 1, 2, 4, 6 and 8 mg/L). The experiment was conducted for six days and the metal induced alterations in the ultrastructure, growth and pigment contents were assessed. Alterations in the ultrastructure of the Synechocystis sp. PCC 6803 cells became evident with the increased (>4 mg/L Pb²⁺) metal concentration. The photosynthetic apparatus (thylakoid membranes) were found to be the worst affected. Deteriorated or completely destroyed thylakoid membranes have made large empty spaces in the cell interior. In addition, at the highest concentration (8 mg/L Pb²⁺), the polyphosphate granules became more prominent both in size and number. Despite the initial slight stimulations (0.2, 3.8 and 6.5% respectively at 0.5, 1 and 2 mg/L Pb²⁺), both metals inhibited the growth in a dose-dependent manner as incubation progressed. Pigment contents (chlorophyll α, β carotene and phycocyanin) were also decreased with increasing metal concentration. Cells exposed to 6 mg/L Pb²⁺, resulted in 36.56, 37.39 and 29.34% reductions of chlorophyll α, β carotene and phycocyanin respectively over the control. Corresponding reductions for the same Cd²⁺concentrations were 57.83, 48.94 and 56.90%. Lethal concentration (96 h LC₅₀) values (3.47 mg/L Cd²⁺ and 12.11 mg/L Pb²⁺) indicated that Synechocystis sp. PCC 6803 is more vulnerable to Cd²⁺ than Pb²⁺. Supported by the Chinese Scholarship Council     

Spatial distribution and diurnal variation of chemical oxygen demand at the beginning of the rainy season in the Changjiang （Yangtze） River Estuary

A field observation was carried out in the Changjiang （Yangtze） River Estuary from May 19 to 26, 2003. A total of 29 stations, including 2 anchored stations, were occupied through almost the whole salinity gradient. Based on the observation data, biogeochemistry of chemical oxygen demand （COD） was examined. Spatial distribution pattern of COD shows that it decreased downstream. The COD concentration varied generally within a narrow range of 1.24-1.60 mg/L in the zone around the river mouth, beyond which it decreased rapidly to 0.20 mg/L. In the mixed water zone, the fluctuation in COD was smaller at 2 m above the bottom layer than at the surface layer in 48 h. In the seawater zone, the 48-h fluctuation at the surface was the largest, followed by that of 5 m below the surface and 2 m above the bottom layers in a range of from 2.50 to 0.55 mg/L. Freshwater discharge was the dominant source of COD in the estuary. The average COD beyond the river mouth was 2.7 mg/L, which accorded with the Chinese seawater quality Grade I. Relationships between dissolved oxygen and biogeochemical parameters such as suspended particulate matter, dissolved organic matter and chlorophyll-a were also discussed.     

4种重金属离子及其混合液对壶状臂尾轮虫的急性毒性试验

研究了铜、锌、镉、铅离子及其混合液对壶状臂尾轮虫(Brachionusurceus)的急性毒性影响,实验结果表明,Cu2+、Zn2+、Cd2+、Pb2+对壶状臂尾轮虫的24hLC50分别为83 .18μg/L、4 .27mg/L、7. 60mg/L、23 44mg/L,将4种离子按照质量比120∶20∶6∶1的比例配成混合金属溶液,其混合液对壶状臂尾轮虫的24hLC50为0 42mg/L。     

Dynamics and relationships of Ca, Mg, Fe in litter, soil fauna and soil in Pinus koraiensis-broadleaf mixed forest

The Liangshui Natural Reserve in Heilongjiang Province of China was selected as the study area. The authors collected the samples of forest litter （Tilia amurensis, Fraxinus mandshurica, Pinus koraiensis, Acer mono, Betula costata, and mixed litter）, soil in humus horizon （0--5cm） and soil horizon （5-20cm）, and soil macrofauna （Oligochaeta, Geophiloporpha and Juliformia） from 2001 to 2002. The role of soil macrofauna in the material cycle was analyzed through comparing the macro-element contents among various parts of the subsystems and using enrichment index （El）. The results indicate that dynamic changes of various litters are very complicated. The contents of Fe in each kind of litter increase firstly, and then decrease in the study period. The changes of macro-element contents are greater in the broad-leaf litter than in the coniferous litter, and the mixed litter is in the middle level, but the differences among them are not significant. The contents of Mg and Fe in humus are higher than those in soil, but the contents of Ca in soil are higher than that in humus. The dynamic changes of macro-element contents in soil and soil fauna are not consistent with those in litter. The diplopod presented obvious enrichment of Ca and Mg （E1〉1）, but it does not significantly enrich Fe. Earthworm has a stronger enrichment ability of Fe than diplopod and scolopendra, but E1〈1. Soil fauna can make great influences on the material cycle of the subsystems.     

EFFECTS OF TEMPERATURE AND Ca^2＋ ON THE LARVAL DEVELOPMENT OF THE DECAPODA CRUSTACEAN ： ERIOCHEIR SINENSIS

With increasing demand in China for the mitten crab larvae, understanding its survival mechanism gets more important. This research focused on the effects of temperature and Ca^2 on the larval growth and development. Eriocheir sinensis larvae were reared in laboratory under 21 different combinations of temperature (15, 20, 25℃) and Ca^2 content (120, 130, 140, 150, 160, 170, 180mg/l) and constant salinity (20) and pH (8), The results suggested that the survival rate increases with temperature and Ca^2 content. These combinations of temperature and Ca2 content maximized survival rate inour study and it may be the optimum water environmental conditions for culturing the larvae. To predict surviving larvae number under different water environmental conditions, 21 dynamic mathematical models were developed. This for the first time observation of the zoeal Ⅵ larvae of the Changjiang River E.sinensis population showed that they occurred under stressed water environmental conditions: temperature of 15℃ and Ca^2 content of 120,130mg/l.     

Simultaneous determination of calcium and magnesium in water using artificial neural network spectro-photometric method

A new analytical method using Back-Propagation(BP) artificial neural networks and spectrophotometry for simultaneous determination of calcium and magnesium in tap water,the Yellow River water and seawater is established.By condition experiment,the optimum analytical conditions for calcium,magnesium and Arsenazo(Ⅲ) color reactions are obtained.Levenberg-Marquart(L-M) algorithm is used for calculation in BP neural network.The topological structure of three-layer BP ANN network architecture is chosen as 11-10-2(nodes).The initial value of gradient coefficient μ is fixed at 0.001 and the increase factor and reduction factor of μ take the default values of the system.The data are processed by computers with our own programs written in MATLAB 7.0.The relative standard deviations of the calculated results for calcium and magnesium are 2.31% and 2.14%,respectively.The results of standard addition method show that the recoveries of calcium and magnesium are 103.6% and 100.8% in the tap water,103.2% and 96.6% in the Yellow River water(Lijin district of Shandong Province),and 98.8%-103.3% and 98.43%-103.4% in seawater from Jiaozhou Bay of Qingdao.It is found that 14 common cations and anions do not interfere with the determination of calcium and magnesium under the optimum experimental conditions.The comparative experiments do not show any obvious difference between the results obtained by this new method and those obtained by the classical complexometric titration method in seawater medium.This method exhibits good reproducibility and high accuracy in the determination of calcium and magnesium and can be used for the simultaneous determination of Ca2+ and Mg2+ in tap water and natural water.     

A NEW BIOGENIC SULFIDE CHEMICAL SENSOR FOR MARINE ENVIRONMENTAL MONITORING AND SURVEY

ＩＮＴＲＯＤＵＣＴＩＯＮＢｉｏｇｅｎｉｃｓｕｌｆｉｄｅｐｒｏｄｕｃｅｄｂｙｂａｃｔｅｒｉａｌｓｕｌｆａｔｅｒｅｄｕｃｔｉｏｎｉｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｉｎｄｉｃａｔｏｒｓｉｎａｎｏｘｉｃｍａｒｉｎｅｅｎｖｉｒｏｎｍｅｎｔｓ,ｐａｒｔｉｃｕｌａｒｌｙｉｎｃｏｎｆｉｎｉｎｇｂａｙｓ,ｐｏｌｌｕｔｅｄｅｓｔｕａｒｉｅｓａｎｄａｑｕａｃｕｌｔｕｒｅａｒ ｅａｓ.Ｔｈｅｉｎｃｒｅａｓｅｏｆｉｔｓｃｏｎｃｅｎｔｒａｔｉｏｎｕｓｕａｌｌｙｉｎｄｉｃａｔｅｓｗｏｒｓｅｎｅｄｃｏｎｄｉｔｉｏｎｓ.…     

粉蕉离体的快速繁殖技术

以粉蕉的吸芽为试材 ,进行了离体快速繁殖研究 ,结果表明 :以改良MS +BA4 .0mg/L(单位下同 ) +AD5.0 +NAA0 .1作诱导培养基 ,外植体褐变率低 ,芽的诱导率高 ,且芽的生长良好 ;以改良MS +BA3- 6 +NAA0 .1为继代培养基 ,可以获得较高的不定芽增殖率 ,在增殖过程中 ,给予一定的低温处理和变化调整BA的用量 ,可以保持较高的增殖率 (2 .6倍以上 ) ,而且芽的长势好 ;生根培养以 1/ 2MS +IBA1.0 +NAA0 .2 +AC1为宜。     

肥城盆地区域地下水化学特征及水质评价

为了解肥城市地下水水化学特征及水质状况,选取20个地下水水质分析数据,综合运用统计分析、Piper三线图,Gibbs图及离子比值等水化学方法,分析了地下水水化学特征,基于模糊综合评价法,对地下水进行了质量评价。结果表明,研究区地下水中阳离子以Ca^2+,Mg^2+为主,阴离子则以HCO^-3,NO^-3,SO 2-4为主,阴、阳离子分别存在HCO^-3>NO^-3>SO 2-4>Cl-和Ca^2+>Mg^2+>Na^+>K^+的关系。TDS介于325.0~1720.0 mg/L之间,均值为741.55 mg/L。地下水呈弱碱性,且属高硬水。地下水化学类型以HCO 3-Ca,HCO 3·SO 4-Ca为主,水-岩作用是地下水水化学组分的主要控制因素,主要受碳酸盐岩的风化溶解控制。研究区地下水以Ⅱ,Ⅲ类水为主,占65%,但Ⅴ类水所占比重也较大,占到了35%。     

湛江港海水中铜、锌、铅、镉的周年变化与水质评价

于2008年3月至2009年1月用电感耦合等离子体质谱法(ICP-MS)对湛江港海水中的铜(Cu)、锌(Zn)、铅(Pb)、镉(Cd)进行调查。分析结果表明:2008年湛江港湾海水中Cu、Zn、Pb、Cd含量较低,年平均含量分别为4.46×10-3mg/L、14.2×10-3mg/L、0.795×10-3mg/L、0.588×10-3mg/L,总体上表层海水中Cu、Zn、Pb、Cd的含量均略低于底层海水。各季度海水中重金属含量的比较结果为:Cu的含量秋季>春季>夏季>冬季,Zn的含量夏季>春季>秋季>冬季,Pb的含量秋季>夏季>春季>冬季,Cd的含量冬季>夏季>秋季>春季。湛江港湾的Cu、Zn、Pb、Cd的含量均在中部水域湛江港码头核心作业区最高,港湾外较低;Zn、Cd在港湾内的含量较高。按照单因子污染指数法评价,湛江港湾海水中的Cu、Zn、Pb、Cd含量均低于国家二类海水水质标准规定的限值,水质较好。