Effects of silver carp (Hypophthalmichthys molitrix) on spring phytoplankton community structure of Three-Gorges Reservoir (China): results from an enclosure experiment

2011 ◽  
Vol 70 (1) ◽  
pp. 26 ◽  
Author(s):  
Guangjie ZHOU ◽  
Xuemin ZHAO ◽  
Yonghong BI ◽  
Zhengyu HU
Keyword(s):  
Community Structure ◽  
Three Gorges Reservoir ◽  
Phytoplankton Community ◽  
Silver Carp ◽  
Three Gorges ◽  
Phytoplankton Community Structure ◽  
Hypophthalmichthys Molitrix ◽  
Enclosure Experiment

scholarly journals Spatial Biomass Production And Seasonal Nutrient Limitation Transitions In A Tributary of The Three Gorges Reservoir, China

2021 ◽  
Author(s):  
Amechi Sampson Nwankwegu ◽  
Yiping Li ◽  
Lei Zhang ◽  
Yanan Huang ◽  
Deti Xie ◽  
...  
Keyword(s):  
Community Structure ◽  
Nutrient Limitation ◽  
Biomass Production ◽  
Three Gorges Reservoir ◽  
Phytoplankton Community ◽  
Freshwater Ecosystem ◽  
Three Gorges ◽  
Phytoplankton Community Structure ◽  
Chl A ◽  
Management Protocol

Abstract The freshwater ecosystem characteristics in terms of nutrient inventory across seasons, spatial variations of chl-a biomass, and the phytoplankton community structure are prudent ecological assessment indices for a bloom management protocol. We evaluated the spatial and seasonal chl-a distribution under different nutrient conditions and phytoplankton community structure in a eutrophic Three Gorges reservoir tributary China. Result showed significant variations in biomass production with the mainstream reaches severely affected. The nutrient addition bioassay demonstrated significant stimulations on growth in both autumn and summer. The nutrient limitation pattern shifted from P in autumn and spring to N limitation during summer. Combined additions of trace metals with N, P, and Si in autumn and Fe alone enrichment in summer and spring showed maximum productivity. The phytoplankton community structure demonstrated strong sensitivities to seasonal variabilities with regime shift from Cyanophyta, dominated by the toxic and hypoxia generating, Microcystis spp in both autumn and summer, the Cryptophyta dominated by the Chroomonas acuta in spring to the Bacilliariophyta dominated by the genera, Cyclotella in winter. This reflected the ability of the Bacilliariophyta to thrive under a low-temperature condition. Combined N&P led to significant growth stimulation in summer while P alone controlled the bulk of the growth in autumn. The study points to the need for extending mitigation steps to the mainstream towards achieving lasting bloom management solution in the impacted tributary.

Seasonal changes in phytoplankton community structure in a bioluminescent lagoon, St. Croix, US Virgin Islands

2018 ◽  
Vol 81 (2) ◽  
pp. 109-124 ◽  
Author(s):  
JL Pinckney ◽  
C Tomas ◽  
DI Greenfield ◽  
K Reale-Munroe ◽  
B Castillo ◽  
...  
Keyword(s):  
Community Structure ◽  
Seasonal Changes ◽  
Phytoplankton Community ◽  
Virgin Islands ◽  
Phytoplankton Community Structure ◽  
Us Virgin Islands

scholarly journals Response of ocean phytoplankton community structure to climate change over the 21st century: partitioning the effects of nutrients, temperature and light

2010 ◽  
Vol 7 (12) ◽  
pp. 3941-3959 ◽  
Author(s):  
I. Marinov ◽  
S. C. Doney ◽  
I. D. Lima
Keyword(s):  
Climate Change ◽  
Community Structure ◽  
Sea Ice ◽  
Phytoplankton Biomass ◽  
Phytoplankton Community ◽  
Vertical Mixing ◽  
Phytoplankton Community Structure ◽  
Marginal Sea ◽  
Small Phytoplankton ◽  
The Impact

Abstract. The response of ocean phytoplankton community structure to climate change depends, among other factors, upon species competition for nutrients and light, as well as the increase in surface ocean temperature. We propose an analytical framework linking changes in nutrients, temperature and light with changes in phytoplankton growth rates, and we assess our theoretical considerations against model projections (1980–2100) from a global Earth System model. Our proposed "critical nutrient hypothesis" stipulates the existence of a critical nutrient threshold below (above) which a nutrient change will affect small phytoplankton biomass more (less) than diatom biomass, i.e. the phytoplankton with lower half-saturation coefficient K are influenced more strongly in low nutrient environments. This nutrient threshold broadly corresponds to 45° S and 45° N, poleward of which high vertical mixing and inefficient biology maintain higher surface nutrient concentrations and equatorward of which reduced vertical mixing and more efficient biology maintain lower surface nutrients. In the 45° S–45° N low nutrient region, decreases in limiting nutrients – associated with increased stratification under climate change – are predicted analytically to decrease more strongly the specific growth of small phytoplankton than the growth of diatoms. In high latitudes, the impact of nutrient decrease on phytoplankton biomass is more significant for diatoms than small phytoplankton, and contributes to diatom declines in the northern marginal sea ice and subpolar biomes. In the context of our model, climate driven increases in surface temperature and changes in light are predicted to have a stronger impact on small phytoplankton than on diatom biomass in all ocean domains. Our analytical predictions explain reasonably well the shifts in community structure under a modeled climate-warming scenario. Climate driven changes in nutrients, temperature and light have regionally varying and sometimes counterbalancing impacts on phytoplankton biomass and structure, with nutrients and temperature dominant in the 45° S–45° N band and light-temperature effects dominant in the marginal sea-ice and subpolar regions. As predicted, decreases in nutrients inside the 45° S–45° N "critical nutrient" band result in diatom biomass decreasing more than small phytoplankton biomass. Further stratification from global warming could result in geographical shifts in the "critical nutrient" threshold and additional changes in ecology.

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