光强度对景观水体水质影响探讨

对景观水体来说,阳光会对水质产生一定的影响,而了解此影响的规律可以为更好的保持景观水质提供依据.在遮光和见光两种环境下对水体进行监测,发现光照首先体现在对藻类的影响上,而藻类的繁殖会对其他指标产生连锁反应,进而影响到整个水质情况.水体表面覆盖一定量的水生植物可以从遮光角度对水质的保持有所帮助.     

混凝法在滇池蓝藻暴发期净水除藻的可行性研究

采用精制硫酸铝为混凝剂,L93^4正交法安排滇池蓝藻暴发期混凝沉降除藻除净水工艺实验。结果表明,混凝剂种类、水样pH值对蓝藻去除率有很大影响。研究确定了混凝剂除藻最佳操作条件,为混凝法去除蓝藻的工业化提供了理论和实际操作依据。     

应用浮动生物滤清器除藻研究

根据浮游植物（藻类）与浮游动物（轮虫类）之间的生态食物链关系，Ｅｌｔｏｎａｉａｎ金字塔风言风语服动生物滤清器”（ＦＢＥ）、在该设备化虫（类）创造了一个生长、系列和栖息的地方，并让它澡类，应用该设备在不同地点进行了实际观测试验，其除藻效率达到８４％～９３％。     

滇池水华综合控制对策探讨

水华污染已成为滇池目前面临的主要环境问题，滇池水华治理被国家列为重中之重的项目而予以高度重视，据多年的监测资料，滇池水华的各类主要是蓝藻门的微囊藻，其次为束丝藻和鱼腥藻。该文从多方面分析了滇池水华泛滥的原因，在此基础上提出了滇池水华控制和富营养化治理的综合对策，特别强调了滇池水华必须坚持控制污染源与生态修复相结合的原则。     

Modelling algal blooms in the Dutch coastal waters by integrated numerical and fuzzy cellular automata approaches

In this paper, an integrated numerical and fuzzy cellular automata model was developed to predict possible algal blooms in Dutch coastal waters basing on the irradiance, nutrients and neighbourhood conditions. The numerical module used Delft3D-WAQ to compute the abiotic conditions, and fuzzy cellular automata approach was applied to predict the algal biomass that was indicated by chlorophyll a concentration. The simulated results of year 1995 were compared with that from BLOOM II model, and the advantages, disadvantages as well as future improvement were presented. In general, through this study, it is seen that the integrated modelling deserves more research inputs because: (1) the hydrodynamic processes and nutrients concentrations can be simulated in details by numerical method; (2) the irregular and sparse water quality and biological data, and the empirical knowledge from experts can be explored by the fuzzy logic technique; (3) the spatial heterogeneity, local interactions and the emerge of patchiness could be well captured through the cellular automata paradigm.     

Seasonal variation in dissolved gaseous mercury and total mercury concentrations in Juam Reservoir, Korea

Dissolved gaseous mercury (DGM) and total mercury (TM) concentrations were measured in Juam Reservoir, Korea. DGM concentrations were higher in spring (64+/-13pgL(-1)) and summer (109+/-15pgL(-1)), and lower in fall (20+/-2pgL(-1)) and winter (23+/-6pgL(-1)). In contrast, TM concentrations were higher in fall (3.2+/-0.1ngL(-1)) and winter (3.3+/-0.1ngL(-1)) than in spring (2.3+/-0.1ngL(-1)) and summer (2.2+/-0.4ngL(-1)). DGM concentrations were correlated with water temperature (p<0.0001), ORP (p<0.0001), UV intensity (UV-A: p=0.008; UV-B: p=0.003), and DOC concentration (p=0.0107). DGM concentrations varied diurnally with UV intensity. The average summer DGM (109+/-15pgL(-1)) and TM (2.2+/-0.4ngL(-1)) concentrations in Juam Reservoir were higher than the averages for North American lakes (DGM=38+/-16pgL(-1); TM=1.0+/-1.2ngL(-1)), but lower than levels reported for Baihua Reservoir in China.     

Epiphytic Algae and Lichen Cover in Boreal Forests—A Long-Term Study Along a N and S Deposition Gradient in Sweden

The aim was to describe spatiotemporal patterns of colonization of spruce branches by algae and lichens and the relationship with decreasing deposition of N and S. Coverage was estimated annually over 10 years for four Swedish Integrated Monitoring catchments with varying deposition levels. Initial hypotheses were that algal coverage would be positively correlated with deposition and that lichen coverage would be negatively correlated with S and positively with N deposition. Data were analyzed using regression, ANOVA, and partial least square regression. The results showed a temporal decrease in the coverage of algae but an increase in colonization rates, while lichens showed less uniform patterns. Within catchments, algae and lichen coverages were positively correlated with mainly S deposition. Across catchments, coverage of algae increased, while the coverage of lichens decreased with increasing N and S deposition. Colonization rates of both algae and lichens showed weak correlations with both spatial and temporal trends in N and S deposition. Thus, while N and S deposition had an effect on the colonization and coverage of algae and lichens, other factors are also important.     

Growth, photosynthetic and respiratory responses to sub-lethal copper concentrations in Scenedesmus incrassatulus (Chlorophyceae)

In the present paper we investigated the effects of sub-lethal concentrations of Cu²⁺ in the growth and metabolism of Scenedesmus incrassatulus. We found that the effect of Cu²⁺ on growth, photosynthetic pigments (chlorophylls and carotenoids) and metabolism do not follow the same pattern. Photosynthesis was more sensitive than respiration. The analysis of chlorophyll a fluorescence transient shows that the effect of sub-lethal Cu²⁺ concentration in vivo, causes a reduction of the active PSII reaction centers and the primary charge separation, decreasing the quantum yield of PSII, the electron transport rate and the photosynthetic O₂ evolution. The order of sensitivity found was: Growth > photosynthetic pigments content = photosynthetic O₂ evolution > photosynthetic electron transport > respiration. The uncoupled relationship between growth and metabolism is discussed.     

Influence of natural dissolved organic carbon on the bioavailability of mercury to a freshwater alga

Bioavailability of mercury (Hg) to Selenastrum capricornutum was assessed in bioassays containing field-collected freshwater of varying dissolved organic carbon (DOC) concentrations. Bioconcentration factor (BCF) was measured using stable isotopes of methylmercury (MeHg) and inorganic Hg(II). BCFs for MeHg in low-DOC lake water were significantly larger than those in mixtures of lake water and high-DOC river water. The BCF for MeHg in rainwater (lowest DOC) was the largest of any treatment. Rainwater and lake water also had larger BCFs for Hg(II) than river water. Moreover, in freshwater collected from several US and Canadian field sites, BCFs for Hg(II) and MeHg were low when DOC concentrations were >5mg L(-1). These results suggest high concentrations of DOC inhibit bioavailability, while low concentrations may provide optimal conditions for algal uptake of Hg. However, variability of BCFs at low DOC indicates that DOC composition or other ligands may determine site-specific bioavailability of Hg.     

Evidence on the causes of the rising levels of CODMn along the middle route of the South-to-North Diversion Project in China: The role of algal dissolved organic matter

As the biggest inter-basin water transfer scheme in the world,the South-to-North Water Diversion Project（SNWD） was designed to alleviate the water crisis in North China.The main channel of the middle route of the SNWD is of great concern in terms of the drinking water quality.In this study,we tested the hypothesis that the dissolved organic matter（DOM） derived from the planktonic algae causes the rising levels of COD_Mn along the middle route by monitoring data on water quality（2015-20...