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排序方式: 共有98条查询结果,搜索用时 62 毫秒
61.
62.
对泉州市区淡水藻类的调查结果显示,市区的淡水藻有28属,其中以后茂的淡水藻资源最为丰富;主要优势藻类是转板藻属、小球藻属及小环藻属;这3个优势藻类适宜的培养溶液分别是海带800倍液、浒苔800倍液及紫菜400倍液。紫菜800倍液对提高藻类生物量的效果最显著。 相似文献
63.
铜绿微囊藻臭氧化以及藻毒素去除研究 总被引:1,自引:0,他引:1
[目的]研究臭氧杀藻机理和藻毒素去除效能,探索富营养化水体藻类处理的可行技术。[方法]采用臭氧氧化技术,针对太湖蓝藻中典型的产毒株——铜绿微囊藻(FACHB-912)进行了杀藻、藻毒素去除效果研究。[结果]臭氧杀藻能够破坏铜绿微囊藻细胞壁,导致胞内物质流失,很少量的臭氧就能够对藻细胞造成损伤,抑制其正常生长代谢。臭氧氧化可以去除藻毒素(MC-LR、MC-RR),10min去除率,LR为82.25%,RR为74.28%。臭氧去除藻毒素受溶液TOC影响,在同样条件下,对分离纯化后藻毒素的去除率LR为95.68%,RR为86.03%。[结论]臭氧化去除铜绿微囊藻效果显著。臭氧对于MC-LR、MC-RR去除效果明显,LR的臭氧降解效率要高于RR。 相似文献
64.
In utero domoic acid toxicity: a fetal basis to adult disease in the California sea lion (Zalophus californianus) 下载免费PDF全文
California sea lions have been a repeated subject of investigation for early life toxicity, which has been documented to occur with increasing frequency from late February through mid-May in association with organochlorine (PCB and DDT) poisoning and infectious disease in the 1970’s and domoic acid poisoning in the last decade. The mass early life mortality events result from the concentrated breeding grounds and synchronization of reproduction over a 28 day post partum estrus cycle and 11 month in utero phase. This physiological synchronization is triggered by a decreasing photoperiod of 11.48 h/day that occurs approximately 90 days after conception at the major California breeding grounds. The photoperiod trigger activates implantation of embryos to proceed with development for the next 242 days until birth. Embryonic diapause is a selectable trait thought to optimize timing for food utilization and male migratory patterns; yet from the toxicological perspective presented here also serves to synchronize developmental toxicity of pulsed environmental events such as domoic acid poisoning. Research studies in laboratory animals have defined age-dependent neurotoxic effects during development and windows of susceptibility to domoic acid exposure. This review will evaluate experimental domoic acid neurotoxicity in developing rodents and, aided by comparative allometric projections, will analyze potential prenatal toxicity and exposure susceptibility in the California sea lion. This analysis should provide a useful tool to forecast fetal toxicity and understand the impact of fetal toxicity on adult disease of the California sea lion. 相似文献
65.
Ingestion,fecundity and population growth of Harpacticus sp. (Harpacticoida,copepod) fed on five species of algae 下载免费PDF全文
We investigated the ingestion, fecundity and population growth of Harpacticus sp. fed on monodiet or mixed diets to evaluate the effects of different algae on Harpacticus sp. Harpacticus sp. fed on diatoms (Skeletonema costatum and Chaetoceros curvisetus) had higher ingestion and pellet production. Time to attain 100% in proportions of gravid females differed, with quickest to slowest: S. costatum, C. curvisetus, Gymnodinium sp. and Heterosigma akashiwo, with the exception of Prymnesium parvum (≤16.67%). S. costatum or C. curvisetus produced higher populations than the other three diets, supported complete development to adulthood, and resulted in doubling copepod population within four days, while no population growth occurred for the other three diets. Mixed‐diet experiments showed that egg production and gross growth efficiencies reduced significantly when fed on H. akashiwo, Gymnodinium sp. or P. parvum mixed with Isochrysis galbana, in comparison with 100% I. galbana. Thus, S. costatum and C. curvisetus were beneficial foods while the other three diets were potentially toxic for Harpacticus sp. The data in this article provide further recognition of nutrient deficiency or toxicity of different algae on copepods. 相似文献
66.
根据2011年5月、2012年8月和2013年8月在连云港田湾核电站邻近海域进行的调查,研究了网采浮游植物的种类组成、年际变化及其与环境因子的关系。该海域共鉴定出浮游植物8门160种,其中硅藻种类数最多(113种),甲藻其次(31种),蓝藻、金藻、黄藻、绿藻、裸藻和隐藻偶有检出。优势种共8种,包括7种硅藻和1种甲藻。相关性分析表明,浮游植物细胞丰度与磷酸盐、亚硝酸盐和温度呈显著正相关,与盐度呈负相关。结合历史数据分析表明,近30年来核电站邻近海域营养盐结构已发生较大变化,表现为硝酸盐浓度急剧升高,由1983年的0.70μmol/L升至2013年的29.38μmol/L,N/P由4.9∶1升至53.7∶1。同时浮游植物群落也有较大变化,表现为优势种呈角毛藻Chaetoceros spp.向骨条藻Skeletonema spp.演替的趋势。 相似文献
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Increased market demand for algal raw materials has stimulated research and development into new cultivation technologies,
particularly in countries with economically important seaweed industries. Chondrus canaliculatus is a red alga endemic to the temperate Pacific coast of South America and produces a complex carrageenan. In Chile, this
potential marine resource has been underutilized since the early 1990s, after it was replaced mainly by imports of Kappaphycus and Eucheum from Asia. The study of the cultivation of C. canaliculatus in outdoor tanks demonstrates the potential to produce large quantities of algal material due to the high productivity observed.
The material produced may be important in Chile as feed for cultured algal herbivores such as Haliotis spp. Data were obtained on the key factors affecting the growth of this alga, including light, temperature, and nutrient
concentrations. The results showed that, on a dry weight basis, productivity varied seasonally between 40 g m−3 wk−1 in autumn and 200 g m−3 wk−1 in spring, and the optimal stocking density in our experiments was 8 kg m−3. Effects of self-shading were among the most important limiting factors in the culture. Discussion is presented on the interactions
between temperature, pH, salinity, enrichment with N and P, and water exchange on the maximal growth of C. canaliculatus in this culture. 相似文献
70.
The rise in global population has led to explorations of alternative sources of energy and food. Because corn and soybean are staple food crops for humans, their common use as the main source of dietary energy and protein for food-producing animals directly competes with their allocation for human consumption. Alternatively, de-fatted marine microalgal biomass generated from the potential biofuel production may be a viable replacement of corn and soybean meal due to their high levels of protein, relatively well-balanced amino acid profiles, and rich contents of minerals and vitamins, along with unique bioactive compounds. Although the full-fatted (intact) microalgae represent the main source of omega-3 (n-3) polyunsaturated fatty acids including docohexaenoic acid (DHA) and eicosapentaenoic acid (EPA), the de-fatted microalgal biomass may still contain good amounts of these components for enriching DHA/EPA in eggs, meats, and milk. This review is written to highlight the necessity and potential of using the de-fatted microalgal biomass as a new generation of animal feed in helping address the globa energy, food, and environmental issues. Nutritional feasibility and limitation of the biomass as the new feed ingredient for simple-stomached species are elaborated. Potential applications of the biomass for generating value-added animal products are also explored. 相似文献