Combined effects of temperature and precipitation on the spring runoff generation process in a seasonal freezing agricultural watershed

This study assessed the impact of increasing seawater surface temperature (SST) and toxic algal abundance (TAA) on the accumulation, tissue distribution and elimination dynamics of paralytic shellfish toxins (PSTs) in mussels. Mytilus coruscus were fed with the PSTs-producing dinoflagellate A. catenella under four simulated environment conditions. The maximum PSTs concentration was determined to be 3548 µg STX eq.kg−1, which was four times higher than the EU regulatory limit. The increasing SST caused a significant decline in PSTs levels in mussels with rapid elimination rates, whereas high TAA increased the PSTs concentration. As a result, the PSTs toxicity levels decreased under the combined condition. Additionally, toxin burdens were assessed within shellfish tissues, with the highest levels quantified in the hepatopancreas. It is noteworthy that the toxin burden shifted towards the mantle from gill, muscle and gonad at the 17th day. Moreover, variability of PSTs was measured, and was associated with changes in each environmental factor. Hence, this study primarily illustrates the combined effects of SST and TAA on PSTs toxicity, showing that increasing environmental temperature is of benefit to lower PSTs toxicity with rapid elimination rates.

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Response of LUCC on Runoff Generation Process in Middle Yellow River Basin: The Gushanchuan Basin

Water ◽

10.3390/w12051237 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1237 ◽

Cited By ~ 1

Author(s):

Caihong Hu ◽

Li Zhang ◽

Qiang Wu ◽

Shan-e-hyder Soomro ◽

Shengqi Jian

Keyword(s):

Climate Change ◽

Human Activities ◽

Yellow River ◽

Trend Test ◽

Generation Process ◽

Runoff Generation ◽

Contribution Rate ◽

Runoff Reduction ◽

Runoff Change ◽

Significant Downward Trend

Runoff reduction in most river basins in China has become a hotpot in recent years. The Gushanchuan river, a primary tributary of the middle Yellow river, Northern China, showed a significant downward trend in the last century. Little is known regarding the relative contributions of changing environment to the observed hydrological trends and response on the runoff generation process in its watershed. On the basis of observed hydrological and meteorological data from 1965–2010, the Mann-Kendall trend test and climate elasticity method were used to distinguish the effects of climate change and human activities on runoff in the Gushanchuan basin. The results indicate that the runoff in the Gushanchuan Basin has experienced significant declines as large as 77% from 1965 to 2010, and a mutation point occurred around 1997; the contribution rate of climate change to runoff change is 12.9–15.1%, and the contribution rate of human activities to runoff change is 84.9–87.1%. Then we divided long-term data sequence into two stages around the mutation point, and analyzed runoff generation mechanisms based on land use and cover changes (LUCC). We found that the floods in the Gushanchuan Basin were still dominated by Excess-infiltration runoff, but the proportion in 1965–1997 and 1998–2010 decreased gradually (68.46% and 45.83% in turn). The proportion of Excess-storage runoff and Mixed runoff has increased, which means that the runoff is made up of more runoff components. The variation law of the LUCC indicates that the forest area increased by 49.61%, the confluence time increased by 50.42%, and the water storage capacity of the watershed increased by 30.35%.

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Combined Effects of Temperature and High pH on Mortality and the Stress Response of Rainbow Trout after Stocking

Transactions of the American Fisheries Society ◽

10.1577/1548-8659(1997)126<0985:ceotah>2.3.co;2 ◽

1997 ◽

Vol 126 (6) ◽

pp. 985-998 ◽

Cited By ~ 21

Author(s):

Eric J. Wagner ◽

Thomas Bosakowski ◽

Steven Intelmann

Keyword(s):

Rainbow Trout ◽

Stress Response ◽

Combined Effects ◽

High Ph ◽

Effects Of Temperature

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Climate Index Weighting Schemes for NWS ESP-Based Seasonal Volume Forecasts

Journal of Hydrometeorology ◽

10.1175/jhm-381.1 ◽

2004 ◽

Vol 5 (6) ◽

pp. 1076-1090 ◽

Cited By ~ 52

Author(s):

Kevin Werner ◽

David Brandon ◽

Martyn Clark ◽

Subhrendu Gangopadhyay

Keyword(s):

Nearest Neighbor ◽

Southern Oscillation ◽

Climate Index ◽

Climate Information ◽

Streamflow Prediction ◽

Forecast System ◽

Ensemble Forecasts ◽

Weighting Schemes ◽

Temperature And Precipitation ◽

Spring Runoff

Abstract This study compares methods to incorporate climate information into the National Weather Service River Forecast System (NWSRFS). Three small-to-medium river subbasins following roughly along a longitude in the Colorado River basin with different El Niño–Southern Oscillation signals were chosen as test basins. Historical ensemble forecasts of the spring runoff for each basin were generated using modeled hydrologic states and historical precipitation and temperature observations using the Ensemble Streamflow Prediction (ESP) component of the NWSRFS. Two general methods for using a climate index (e.g., Niño-3.4) are presented. The first method, post-ESP, uses the climate index to weight ensemble members from ESP. Four different post-ESP weighting schemes are presented. The second method, preadjustment, uses the climate index to modify the temperature and precipitation ensembles used in ESP. Two preadjustment methods are presented. This study shows the distance-sensitive nearest-neighbor post-ESP to be superior to the other post-ESP weighting schemes. Further, for the basins studied, forecasts based on post-ESP techniques outperformed those based on preadjustment techniques.

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