Combined studies of latitudinal and interannual variations of annual phytoplankton bloom peak in East Asian marginal seas(17°–58°N, including the northern South China Sea(SCS), Kuroshio waters, the Sea of J...Combined studies of latitudinal and interannual variations of annual phytoplankton bloom peak in East Asian marginal seas(17°–58°N, including the northern South China Sea(SCS), Kuroshio waters, the Sea of Japan and the Okhotsk Sea) are rarely. Based on satellite-retrieved ten-year(2003–2012) median timing of the annual Chlorophyll a concentration(Chl a) climax, here we report that this annual spring bloom peak generally delays from the SCS in January to the Okhotsk Sea in June at a rate of(21.20±2.86) km/d(decadal median±SD). Spring bloom is dominant feature of the phytoplankton annual cycle over these regions, except for the SCS which features winter bloom. The fluctuation of the annual peak timing is mainly within ±48 d departured from the decadal median peak date, therefore this period(the decadal median peak date ±48 d) is defined as annual spring bloom period. As sea surface temperature rises, earlier spring bloom peak timing but decreasing averaged Chl a biomass in the spring bloom period due to insufficient light is evident in the Okhotsk Sea from 2003 to 2012. For the rest of three study domains, there are no significant interannual variance trend of the peak timing and the averaged Chl a biomass. Furthermore this change of spring phytoplankton bloom timing and magnitude in the Okhotsk Sea challenges previous prediction that ocean warming would enhance algal productivity at high latitudes.展开更多
Recent advances in hydraulic modeling create improved methodology to accurately predict the extent of floodplain map in order to assist policy makers to develop flood hazard mitigation measures and timely inform the l...Recent advances in hydraulic modeling create improved methodology to accurately predict the extent of floodplain map in order to assist policy makers to develop flood hazard mitigation measures and timely inform the local communities with the flood risk alerts.However,accurate prediction of the inundation map also depends on the spatial resolution of the topographic data.In this study,we developed a novel high-resolution modeling framework for Nashwaak River watershed,New Brunswick,Canada to capture significant flooding along the banks of the river for the two historic flood events and accurately map the floodplains for both the gauged and ungauged areas of the watershed.The model is based on HEC-RAS(US Army Corps of Engineers Hydrologic Engineering Center River Analysis System)hydraulic model and the topographic data were generated from high-resolution LiDAR data of~0.5 m.The model runs were driven by observed flow conditions applied at the boundary and the framework is based on different spatial resolution to determine the effect of spatial resolution on the predicted inundation.We validated the model simulated water surface elevation with the observed data and the model reproduces reasonably good skill score.Results from the numerical simulation suggest that apart from the strength of the stream velocity,design of the modeling framework plays an important role in determining the inundation depth as well as the maximum flooding extent.展开更多
There have been a number of applications of satellite altimetry to seasonal and interannual sea level variability in the South China Sea. However, these applications usually exclude shallow waters along the coast, wit...There have been a number of applications of satellite altimetry to seasonal and interannual sea level variability in the South China Sea. However, these applications usually exclude shallow waters along the coast, with one of the concerns being large aliased tide-correction error. In this study the authors analyzed 14 years of merged satellite altimeter data to obtain the amplitude and phase of the semi-annual cycle and to examine the variation at the K1 alias frequency (close to the semi-annual frequency). The results indicate that the amplitude of the semi-annual cycle ranges from 3-7 cm, substantial compared with that of the annual cycle; while the amplitude at the K1 alias frequency (error of the K1 tidal correction) is essentially 1 cm only. Altimeter-derived semi-annual cycle is in good agreement with that from independent tide-gauge observations, pointing to the competent ability of satellite altimetry in observing semi-annual sea level variations in the South China Sea.展开更多
This study investigated estuarine acidification, associated with drainage and excavation of acid sulfate soils, in areas used for commercial cultivation of Sydneyrock oysters (Saccostrea glomerata). Regular measuremen...This study investigated estuarine acidification, associated with drainage and excavation of acid sulfate soils, in areas used for commercial cultivation of Sydneyrock oysters (Saccostrea glomerata). Regular measurements of pH and electrical conductivity were collected in oyster cultivation areas and acidified reaches of the Hastings River estuary and Port Stephens estuary located on the mid north coast of New South Wales, Australia. Water quality information from acidified floodplain drains was also collected in theHastingsRiverfollowing heavy rainfall. Both estuaries experienced acidification of tributaries following periods of heavy rainfall. Drain outflow waters were acidic展开更多
Coastal inundation along the northeast coast of the United States is usually caused by strong winter storms(WS).However,the accurate prediction of coastal inundation due to the WS is challenging.Therefore,our study ai...Coastal inundation along the northeast coast of the United States is usually caused by strong winter storms(WS).However,the accurate prediction of coastal inundation due to the WS is challenging.Therefore,our study aims to develop a unique high-resolution modeling system to accurately predict the coastal inundation in the ungauged coastal areas of Saco-Casco Bays and map the flood risk zones to potential sea level rise due to these storms.Hindcasts of five classic WS in 2014-2015 were studied.The inundation models are based on FVCOM that uses unstructured grid to capture the minor to significant flooding near the shallow areas of the bays,harbor entrance and river banks.In this study,topography has been generated from the NOAA’s integrated dataset of Portland,ME 1/3 arc-second MHW digital elevation model.The model runs were driven by two different sets of meteorological(NECOFS WRF and NOAA’s NAM WRF)forcing to examine the effect of spatial resolution on the predicted inundation.The study reveals that among the five storm surge cases,WS-III produces a maximum surge of 0.7 m and WS-II cause a minimum surge of 0.3 m.In all scenarios,southward wind-driven coastal current flowing towards Biddeford Pool,Pine Point and Camp Ellis forms a small-scale eddy which causes significant inundation however strength of the current varies accordingly.Sensitivity experiments have been carried out using NECOFS WRF simulation products with varying parameters of marshland elevation and bottom friction to understand the influence of intertidal storage on the predicted flooding.展开更多
利用1993--2006年1～12月AIPO （The joining area of Asia and Indian-Pacific Ocean）流场数据，分析了吕宋海峡120。E断面水交换流速结构的平均月际变化特征，并计算了通过该断面的水通量，探讨了水通量及其垂向结构的月际和季节变...利用1993--2006年1～12月AIPO （The joining area of Asia and Indian-Pacific Ocean）流场数据，分析了吕宋海峡120。E断面水交换流速结构的平均月际变化特征，并计算了通过该断面的水通量，探讨了水通量及其垂向结构的月际和季节变化特征。结果表明：①在断面的南北方向，西向流和东向流分别大致以19．5°N和21．5°N线为界，二者交替相间分布，呈“两进（西向流入南海）两出（东向流出南海）”的结构；21．5°N以南的300m以深和21．5°N以北的1000m以浅海域，常年存在南海水东向流入太平洋。②上层、深层和整个断面的净水通量几乎均为西向流，净水通量冬季最大，春季和秋季次之，夏季最小。中层除12月外，其他各月的净水通量均为东向流出南海，净水通量春季最大，夏季和秋季次之，冬季最小。③整个断面的净水通量，1～5月和8～11月呈“三明治”结构，6～7月呈2层结构；12月呈单层结构，年平均呈“三明治”结构。展开更多
The CRISPR-Cas9 genome editing has many advantages over its counterparts and could ultimately assist in disease control and molecular breeding in aquaculture.Single-guide RNA(sgRNA)design is presumably the most crucia...The CRISPR-Cas9 genome editing has many advantages over its counterparts and could ultimately assist in disease control and molecular breeding in aquaculture.Single-guide RNA(sgRNA)design is presumably the most crucial task in a typical CRISPR-Cas9 experiment;an understanding of algorithms behind sgRNA design programs is thus essential for improved efficacy and specificity.We focus this review on the bioinformatics aspects in genome editing experiments and describe commonly used computational approaches and tools of sgRNA design and outcome assessment.We show an example of sgRNA design with optimal parameter settings and appropriate interpretation of results and present a brief overview of CRISPR-Cas9 applications,such as genetic improvement and sustainability in aquaculture.We discuss challenging issues,particularly in the context of computational biology,in the use of computational tools in CRISPR-based genome editing.This review provides a synthesis of bioinformatics tools used for CRISPR-Cas9 sgRNA design and outcome assessment and offers a general view of CRISPR-based applications in farmed fish,which are expected to facilitate genome editing programs and hence improve aquaculture breeding,production,and sustainability.展开更多
Gillnets are the primary fishing gear used to catch Atlantic cod(Gadus morhua)in coastal areas of Newfoundland and Labrador but are known to catch non-target species and produce lower quality fish than live-catch meth...Gillnets are the primary fishing gear used to catch Atlantic cod(Gadus morhua)in coastal areas of Newfoundland and Labrador but are known to catch non-target species and produce lower quality fish than live-catch methods.The purpose of this study was to compare the catch efficiency of collapsible cod pots against gillnets near the Gilbert Bay Marine Protected Area(MPA),Labrador,where a reduction in by-catch is needed.Results showed that one cod pot caught half as much Atlantic cod as a gillnet,and pots had a relatively stable catch rate throughout the sampling period,whereas gillnets caught relatively few fish later in the sampling season.Moreover,nearly all fish sampled with pots were caught alive undamaged,whereas most gillnet-caught fish experienced damage or mortality.As a conservation measure pot-fishing would enable fishing within close proximity to the Gilbert Bay MPA and the live-release of visually distinguishable Gilbert Bay cod,thereby mitigating against the negative effects of commercial fishing on this protected Atlantic cod population.展开更多
Irrigation infrastructure expansion threatens the diversity of freshwater fish worldwide.Irrigation infrastructure creates migration barriers which can block access to important nursery,feeding and spawning habitat.La...Irrigation infrastructure expansion threatens the diversity of freshwater fish worldwide.Irrigation infrastructure creates migration barriers which can block access to important nursery,feeding and spawning habitat.Lao PDR is a landlocked country situated within the Lower Mekong River Basin where there is a substantial dependency on rice and fish for food,income and livelihoods.The country is experiencing an unprecedented boom in irrigation infrastructure investment,with modernisation programs being implemented in every province.Despite significant investment in infrastructure upgrades,and the potential impact on freshwater fish,little consideration has been given to fish passage solutions.In 2008,we commenced a fish passage program in Lao PDR.The intent of this case study is to outline the pivotal elements of the program of knowledge development and transfer,in the context of river connectivity and fisheries management in Lao PDR.We also highlight challenges in international research in development and lessons learned.展开更多
基金The scientific research fund of the Second Institute of Oceanography,State Oceanic Administration,China under contract No.JG1417the Public Science and Technology Research Funds Projects of Ocean under contract No.201005030the National Natural Science Foundation of China under contract Nos 41476156 and 41321004
文摘Combined studies of latitudinal and interannual variations of annual phytoplankton bloom peak in East Asian marginal seas(17°–58°N, including the northern South China Sea(SCS), Kuroshio waters, the Sea of Japan and the Okhotsk Sea) are rarely. Based on satellite-retrieved ten-year(2003–2012) median timing of the annual Chlorophyll a concentration(Chl a) climax, here we report that this annual spring bloom peak generally delays from the SCS in January to the Okhotsk Sea in June at a rate of(21.20±2.86) km/d(decadal median±SD). Spring bloom is dominant feature of the phytoplankton annual cycle over these regions, except for the SCS which features winter bloom. The fluctuation of the annual peak timing is mainly within ±48 d departured from the decadal median peak date, therefore this period(the decadal median peak date ±48 d) is defined as annual spring bloom period. As sea surface temperature rises, earlier spring bloom peak timing but decreasing averaged Chl a biomass in the spring bloom period due to insufficient light is evident in the Okhotsk Sea from 2003 to 2012. For the rest of three study domains, there are no significant interannual variance trend of the peak timing and the averaged Chl a biomass. Furthermore this change of spring phytoplankton bloom timing and magnitude in the Okhotsk Sea challenges previous prediction that ocean warming would enhance algal productivity at high latitudes.
基金funded by the ETFNB Environmental Trust Fund of New Brunswick(grant No.170099).
文摘Recent advances in hydraulic modeling create improved methodology to accurately predict the extent of floodplain map in order to assist policy makers to develop flood hazard mitigation measures and timely inform the local communities with the flood risk alerts.However,accurate prediction of the inundation map also depends on the spatial resolution of the topographic data.In this study,we developed a novel high-resolution modeling framework for Nashwaak River watershed,New Brunswick,Canada to capture significant flooding along the banks of the river for the two historic flood events and accurately map the floodplains for both the gauged and ungauged areas of the watershed.The model is based on HEC-RAS(US Army Corps of Engineers Hydrologic Engineering Center River Analysis System)hydraulic model and the topographic data were generated from high-resolution LiDAR data of~0.5 m.The model runs were driven by observed flow conditions applied at the boundary and the framework is based on different spatial resolution to determine the effect of spatial resolution on the predicted inundation.We validated the model simulated water surface elevation with the observed data and the model reproduces reasonably good skill score.Results from the numerical simulation suggest that apart from the strength of the stream velocity,design of the modeling framework plays an important role in determining the inundation depth as well as the maximum flooding extent.
基金Canadian Space Agency Government Research Initiative ProgramNASA Ocean Surface Topography Science Team Program
文摘There have been a number of applications of satellite altimetry to seasonal and interannual sea level variability in the South China Sea. However, these applications usually exclude shallow waters along the coast, with one of the concerns being large aliased tide-correction error. In this study the authors analyzed 14 years of merged satellite altimeter data to obtain the amplitude and phase of the semi-annual cycle and to examine the variation at the K1 alias frequency (close to the semi-annual frequency). The results indicate that the amplitude of the semi-annual cycle ranges from 3-7 cm, substantial compared with that of the annual cycle; while the amplitude at the K1 alias frequency (error of the K1 tidal correction) is essentially 1 cm only. Altimeter-derived semi-annual cycle is in good agreement with that from independent tide-gauge observations, pointing to the competent ability of satellite altimetry in observing semi-annual sea level variations in the South China Sea.
文摘This study investigated estuarine acidification, associated with drainage and excavation of acid sulfate soils, in areas used for commercial cultivation of Sydneyrock oysters (Saccostrea glomerata). Regular measurements of pH and electrical conductivity were collected in oyster cultivation areas and acidified reaches of the Hastings River estuary and Port Stephens estuary located on the mid north coast of New South Wales, Australia. Water quality information from acidified floodplain drains was also collected in theHastingsRiverfollowing heavy rainfall. Both estuaries experienced acidification of tributaries following periods of heavy rainfall. Drain outflow waters were acidic
文摘Coastal inundation along the northeast coast of the United States is usually caused by strong winter storms(WS).However,the accurate prediction of coastal inundation due to the WS is challenging.Therefore,our study aims to develop a unique high-resolution modeling system to accurately predict the coastal inundation in the ungauged coastal areas of Saco-Casco Bays and map the flood risk zones to potential sea level rise due to these storms.Hindcasts of five classic WS in 2014-2015 were studied.The inundation models are based on FVCOM that uses unstructured grid to capture the minor to significant flooding near the shallow areas of the bays,harbor entrance and river banks.In this study,topography has been generated from the NOAA’s integrated dataset of Portland,ME 1/3 arc-second MHW digital elevation model.The model runs were driven by two different sets of meteorological(NECOFS WRF and NOAA’s NAM WRF)forcing to examine the effect of spatial resolution on the predicted inundation.The study reveals that among the five storm surge cases,WS-III produces a maximum surge of 0.7 m and WS-II cause a minimum surge of 0.3 m.In all scenarios,southward wind-driven coastal current flowing towards Biddeford Pool,Pine Point and Camp Ellis forms a small-scale eddy which causes significant inundation however strength of the current varies accordingly.Sensitivity experiments have been carried out using NECOFS WRF simulation products with varying parameters of marshland elevation and bottom friction to understand the influence of intertidal storage on the predicted flooding.
文摘利用1993--2006年1～12月AIPO （The joining area of Asia and Indian-Pacific Ocean）流场数据，分析了吕宋海峡120。E断面水交换流速结构的平均月际变化特征，并计算了通过该断面的水通量，探讨了水通量及其垂向结构的月际和季节变化特征。结果表明：①在断面的南北方向，西向流和东向流分别大致以19．5°N和21．5°N线为界，二者交替相间分布，呈“两进（西向流入南海）两出（东向流出南海）”的结构；21．5°N以南的300m以深和21．5°N以北的1000m以浅海域，常年存在南海水东向流入太平洋。②上层、深层和整个断面的净水通量几乎均为西向流，净水通量冬季最大，春季和秋季次之，夏季最小。中层除12月外，其他各月的净水通量均为东向流出南海，净水通量春季最大，夏季和秋季次之，冬季最小。③整个断面的净水通量，1～5月和8～11月呈“三明治”结构，6～7月呈2层结构；12月呈单层结构，年平均呈“三明治”结构。
基金This publication was made possible through funding support from the National Science Foundation(DBI-1919574)and the University of Nebraska at Omaha.
文摘The CRISPR-Cas9 genome editing has many advantages over its counterparts and could ultimately assist in disease control and molecular breeding in aquaculture.Single-guide RNA(sgRNA)design is presumably the most crucial task in a typical CRISPR-Cas9 experiment;an understanding of algorithms behind sgRNA design programs is thus essential for improved efficacy and specificity.We focus this review on the bioinformatics aspects in genome editing experiments and describe commonly used computational approaches and tools of sgRNA design and outcome assessment.We show an example of sgRNA design with optimal parameter settings and appropriate interpretation of results and present a brief overview of CRISPR-Cas9 applications,such as genetic improvement and sustainability in aquaculture.We discuss challenging issues,particularly in the context of computational biology,in the use of computational tools in CRISPR-based genome editing.This review provides a synthesis of bioinformatics tools used for CRISPR-Cas9 sgRNA design and outcome assessment and offers a general view of CRISPR-based applications in farmed fish,which are expected to facilitate genome editing programs and hence improve aquaculture breeding,production,and sustainability.
基金The study was funded by the Fisheries and Oceans Canada.
文摘Gillnets are the primary fishing gear used to catch Atlantic cod(Gadus morhua)in coastal areas of Newfoundland and Labrador but are known to catch non-target species and produce lower quality fish than live-catch methods.The purpose of this study was to compare the catch efficiency of collapsible cod pots against gillnets near the Gilbert Bay Marine Protected Area(MPA),Labrador,where a reduction in by-catch is needed.Results showed that one cod pot caught half as much Atlantic cod as a gillnet,and pots had a relatively stable catch rate throughout the sampling period,whereas gillnets caught relatively few fish later in the sampling season.Moreover,nearly all fish sampled with pots were caught alive undamaged,whereas most gillnet-caught fish experienced damage or mortality.As a conservation measure pot-fishing would enable fishing within close proximity to the Gilbert Bay MPA and the live-release of visually distinguishable Gilbert Bay cod,thereby mitigating against the negative effects of commercial fishing on this protected Atlantic cod population.
基金The program was funded by the Australian Centre for International Agricultural Research.
文摘Irrigation infrastructure expansion threatens the diversity of freshwater fish worldwide.Irrigation infrastructure creates migration barriers which can block access to important nursery,feeding and spawning habitat.Lao PDR is a landlocked country situated within the Lower Mekong River Basin where there is a substantial dependency on rice and fish for food,income and livelihoods.The country is experiencing an unprecedented boom in irrigation infrastructure investment,with modernisation programs being implemented in every province.Despite significant investment in infrastructure upgrades,and the potential impact on freshwater fish,little consideration has been given to fish passage solutions.In 2008,we commenced a fish passage program in Lao PDR.The intent of this case study is to outline the pivotal elements of the program of knowledge development and transfer,in the context of river connectivity and fisheries management in Lao PDR.We also highlight challenges in international research in development and lessons learned.
