期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
ENCLOSURE EXPERIMENTS ON AND LACUSTRINE PRACTICE FOR ELIMINATING MICROCYSTIS BLOOM 被引量:5
1
作者 刘建康 谢平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第2期113-117,共5页
Microcystis bloom, one of the most objectionable characteristics of eutrophication in tropical and subtropical waters, occurred in Donghu Lake (East Lake) of Wuhan every summer from the 1970s up to 1984, but from 1985... Microcystis bloom, one of the most objectionable characteristics of eutrophication in tropical and subtropical waters, occurred in Donghu Lake (East Lake) of Wuhan every summer from the 1970s up to 1984, but from 1985 up to now failed to occur there. The cause of its disappearance remained in obscurity until recently. In situ enclosure experiments in the lake for three years showed that the stocking of the filter-feeding silver carp (Hypophthalmichthys molitrix) and big-head carp (Aristichthys nobilis) played a decisive role in eliminating Microcystis bloom from the lake; but that recurrence of the bloom is possible under certain conditions. This paper presents the details and the results of enclosure experiments. The authors’ analysis of fish biomass data obtained by echo-sounding and the fishery production of the lake over the years, revealed that the recurrence of Microcystis bloom can be prevented so long as the combined biomass of silver carp and big-head carp remains at or exceeds 50 g per cubic meter of lakewater, as was the case in the lake’s 1985 fish yield of 1015 t. 展开更多
关键词 Microcystis bloom elimination enclosure experiments silver carp (Hypophthalmichthys molitrix) big-head carp (Aristichthys nobilis) fish-stocking practice of Donghu Lake
下载PDF
Effects of a mixture of Cu, Cd, Hg and Zn on marine plankton: Marine Ecosystem Enclosure Experiment
2
作者 Wu Jinping Third Institute of Oceanography, State Oceanic Administration, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第1期145-150,共6页
Five experiment ecosystems (MEEE) were employed in April, 1985 to test the effects of a mixture of Cu, Cd, Hg, Pb and Zn on a subtropical planktonic ecosystem in Xiamen Bay, Xiamen, China. The results indicated that t... Five experiment ecosystems (MEEE) were employed in April, 1985 to test the effects of a mixture of Cu, Cd, Hg, Pb and Zn on a subtropical planktonic ecosystem in Xiamen Bay, Xiamen, China. The results indicated that the ppb-level of the mixture could suppress the planktonic production. Zooplankton in Xiamen were very sensitive to the metal contamination, especially the larvaceans. 展开更多
关键词 Marine Ecosystem enclosure experiment Hg and Zn on marine plankton Effects of a mixture of Cu ZN
下载PDF
Eutrophication and algal blooms in channel type reservoirs:A novel enclosure experiment by changing light intensity 被引量:12
3
作者 Chengjin Cao Binghui Zheng +2 位作者 Zhenlou Chen Minsheng Huang Jialei Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第10期1660-1670,共11页
To explore eutrophication and algal bloom mechanisms in channel type reservoirs, a novel enclosure experiment was conducted by changing light intensity (LI) in the Daning River of the Three Gorges Reservoir (TGR).... To explore eutrophication and algal bloom mechanisms in channel type reservoirs, a novel enclosure experiment was conducted by changing light intensity (LI) in the Daning River of the Three Gorges Reservoir (TGR). Square enclosures (side 5.0 m) were covered on the surface with shading materials of different thickness, and with their bases open to the river. Changes and characteristics of the main eutrophication factors under the same water quality and hydrodynamic conditions but different LI were evaluated. All experimental water samples were neutral and alkalescent, with high nitrogen and phosphate concentrations, low potassium permanganate index, stable water quality, and different LI. At the same water depth, LI decreased with increasing shade material, while dissolved oxygen and water temperature were both stable. The growth peak of phytoplankton was with light of 345-4390 lux underwater or 558-7450 lux above the water surface, and water temperature of 25.6--26.5℃. Algae were observed in all water samples, accounting for 6 phylum and 57 species, with algal density changing frequently. The results showed that significantly strong or weak light was unfavorable for phytoplankton growth and the function together with suitable temperature and LI and ample sunshine encouraged algal blooms under the same water quality and hydrodynamic conditions. Correlation analysis indicated that algae reduced gradually lengthwise along water depth in the same enclosure while pH became high. The power exponent relationship between chlorophyll a (Chl-a) and LI was found by curve fitting, that is Chl-a = K(LI)n. 展开更多
关键词 EUTROPHICATION algal bloom enclosure experiment channel type reservoirs Three Gorges Reservoir
原文传递
The pathway and fate of the heavy metal mixture in Xiamen marine experiment enclosures
4
作者 Li Jinxia, Du Ronggui, Zhang Gongxun , C. S. Wong, R. W. Macdonald2 and W. K. Johnson2 Third Institute of Oceanography, State Oceanic Administration, Xiamen , China Institute of Ocean Sciences, P. O. Box 6000, Sidney, B. C. V8L 4B2, Canada 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第3期389-403,共15页
The pathway and fate of heavy metals were studied in 10m3 enclosures at Xiamen Bay in 1985. The dissolved metals added are removed rather quickly during the first days, and their half-removal times ( t1/2) (d) are as ... The pathway and fate of heavy metals were studied in 10m3 enclosures at Xiamen Bay in 1985. The dissolved metals added are removed rather quickly during the first days, and their half-removal times ( t1/2) (d) are as follows: Pb 5. 4-5. 8, Hg 6. 7-14, Zn 11-22, Cu 16 - 29, and Cd 30-89. Zinc is transferred biologically to particles during phytoplankton bloom. The main Fate of added metals after 27 days is as follows; over 80% Cd and 60% Cu remain in dissolved phase, more than 60% Pb and 50% Hg transfer to settling settlement, while Zn is equally distributed in dissolved phase and settling settlement. The wall uptake is less than 2% of the total metals added. Organic materials play an essential role in the partition and the transfer of heavy metals in water column. Terrigenous and autochthonous particles show different affinities to different metals. Most heavy metals associate weakly with zooplankton. The Binding of Cd, Pb, Zn and Cu to the particles shows distinctive features related to the diagenetic alteration. 展开更多
关键词 The pathway and fate of the heavy metal mixture in Xiamen marine experiment enclosures
下载PDF
Effect of flow rate on environmental variables and phytoplankton dynamics:results from field enclosures 被引量:3
5
作者 张海平 陈瑞弘 +1 位作者 李飞鹏 陈玲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期430-438,共9页
To investigate the effects of flow rate on phytoplankton dynamics and related environment variables,a set of enclosure experiments with different fl ow rates were conducted in an artificial lake. We monitored nutrient... To investigate the effects of flow rate on phytoplankton dynamics and related environment variables,a set of enclosure experiments with different fl ow rates were conducted in an artificial lake. We monitored nutrients,temperature,dissolved oxygen,p H,conductivity,turbidity,chlorophyll-a and phytoplankton levels. The lower biomass in all flowing enclosures showed that flow rate significantly inhibited the growth of phytoplankton. A critical flow rate occurred near 0.06 m/s,which was the lowest relative inhibitory rate. Changes in flow conditions affected algal competition for light,resulting in a dramatic shift in phytoplankton composition,from blue-green algae in still waters to green algae in flowing conditions. These findings indicate that critical flow rate can be useful in developing methods to reduce algal bloom occurrence. However,flow rate significantly enhanced the inter-relationships among environmental variables,in particular by inducing higher water turbidity and vegetative reproduction of periphyton( Spirogyra). These changes were accompanied by a decrease in underwater light intensity,which consequently inhibited the photosynthetic intensity of phytoplankton. These results warn that a universal critical flow rate might not exist,because the effect of flow rate on phytoplankton is interlinked with many other environmental variables. 展开更多
关键词 environmental variables PHYTOPLANKTON enclosure experiment flow rate
下载PDF
Organic carbon budget in shrimp polyculture enclosure ecosystems
6
作者 Liu Guocai Li Deshang +2 位作者 Dong Shuanglin Chen Zhaobo Lu Jing X(1. Ocean University of Qingdao, Qingdao 266003, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第1期99-108,共10页
The organic carbon budget in shrimp polyculture ecosystems was studied with five experimental enclosures. The results showed that: (l ) the total Organic carbon income of the ecosystems varied from 4 847. 46 to 6 15... The organic carbon budget in shrimp polyculture ecosystems was studied with five experimental enclosures. The results showed that: (l ) the total Organic carbon income of the ecosystems varied from 4 847. 46 to 6 154. 67 g, averaged (5 646. 94 t 551.09) g, the average ratio among its components, i. e., (phytoplankton production ): (periphyte production ): (feed casted) was 0. 73: 0. 11: 0. 16; (2) the total output of organic carbon varied from 3 310. 28 to 3 974. 79 g, averaged (3 644. 21 281. 44) g, the average ratio among its components, i. e., (plankton community respiration): (periphyton respiration): (benthic community): (culture animal production): (culture animal respiration) was 0. 53: 0. 19: 0. 15: 0. 04:0. 09; (3) the organic carbon accumulation varied from 1 383. 45 to 2 707. 31 g, averaged (2 002. 73 546. 76) g, which was 26% --44 % of the total organic carbon income; the sequence of organic carbon accumulation in the ecosystems of different polyculture types was Y5 (Penaeus chinensis -- Argopecten irradians) > Y7 (P. chinensis -- Taiwan red tilapia) > Y4 (P. chinensis ) > T5 (P. chinensis -- Taiwan red tilapia -- Sinonovacula constricta ) > Y6 (P. chinensis S. constricta ); (4) the average conversion rate of organic carbon income to P. chinensis was (l. 77 0. 62) % (Y6>T5 > Y4 >YS > Y7), and that to total culture animals was (2. 18 0. 79) % (T5 >Y6 > Y5 > Y4 > Y7). 展开更多
关键词 Shrimp polyculture organic carbon BUDGET enclosure experiment
下载PDF
Influence of sunlight on the proliferation of cyanobacterial blooms and its potential applications in Lake Taihu, China 被引量:6
7
作者 Qichao Zhou Wei Chen +2 位作者 Kun Shan Lingling Zheng Lirong Song 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第3期626-635,共10页
To learn the relationship between sunlight intensity and cyanobacterial proliferations for the further control of the heavy blooms, enclosure experiment were conducted in Meiliang Bay, Lake Taihu by regulating the nat... To learn the relationship between sunlight intensity and cyanobacterial proliferations for the further control of the heavy blooms, enclosure experiment were conducted in Meiliang Bay, Lake Taihu by regulating the natural light intensities with different shading ratio (0% (full sunlight), 10%, 25%, 50% and 75% of original natural sunlight intensities) from September to November in 2010. The results indicated that phytoplankton biomass (mean) decreased significantly when the shading ratios reached 50% or more. Higher shading ratios (e.g. 75%) were very efficient in controlling the average and total cyanobacterialbloom biomass, while 50% shading ratio was proven very effective either in controlling the peak value of phytoplankton biomass or postponing the occurrence of cyanobacterial blooms in Lake Talhu. In addition, phytoplankton composition and photosynthesis efficiency were also affected by altering the shading ratios, and in turn, they might also act on phytoplankton growth. Based on the results from the present study, intermediate shading strategies such as regulation of water level or turbidity through the hydrology regulations would probably be an effective and efficient method in controlling cyanobacterial blooms in large and shallow lakes. 展开更多
关键词 light cyanobacterial bloomscontrol Lake Taihu enclosure experiment
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部