Fish otolithδ^(15) N(δ^(15) N_(oto))is a demonstrated source of information of dietary history for marine fi sh as it is available iN_(oto)lith archives and sedimentary deposits unlike white muscle tissue(WMT).WMT a...Fish otolithδ^(15) N(δ^(15) N_(oto))is a demonstrated source of information of dietary history for marine fi sh as it is available iN_(oto)lith archives and sedimentary deposits unlike white muscle tissue(WMT).WMT and stomach content data are insufficient for trophic level(TL)data of past fi shes which is important for the changes of marine fi shery resources over long time scales.To determine the correlation betweenδ^(15) N_(oto) and fi sh WMTδ^(15) N(δ^(15) N_(wmt))and the feasibility of usingδ^(15) N_(oto) in characterizing the TLs of marine fi shes,we conducted nitrogen stable isotope analysis(SIA)in the otolith and WMT of 36 marine fi sh species sampled from the Yellow Sea and northern East China Sea in 2011-2014.Bothδ^(15) N_(oto) andδ^(15) N_(wmt) were analyzed using an elemental analyzer coupled with an isotope ratio mass spectrometer(EA-IRMS).Multiple otoliths were combined to make each otolith measurement and were analyzed as-is without a carbonate dissolution pre-processing step.δ^(15) N_(oto) andδ^(15) N_(wmt) comparisons for species in the Yellow Sea and northern East China Sea are currently lacking and would be helpful for both regional studies and for increasing the number of species for whichδ^(15) N_(oto) andδ^(15) N_(wmt) have been compared.Additionally,to determine the relative accuracy of trophic level calculated usingδ^(15) N_(oto),we compared TL calculated fromδ^(15) N_(oto) to traditional trophic level metrics calculated usingδ^(15) N_(wmt).The results showed a positive and highly signifi cant correlation(R=0.780,P<0.001)betweenδ^(15) N_(oto) andδ^(15) N_(wmt).Trophic level estimation using WMT(TL wmt)and otolith(TL oto)showed congruence in our study,which is not entirely surprising given thatδ^(15) N_(oto) was regressed againstδ^(15) N_(wmt) and the resulting regression coefficient was used to convertδ^(15) N_(oto) toδ^(15) N_(wmt) prior to calculating TL oto.This conversion was required in order to be consistent with previousδ^(15) N_(wmt)-based calculations of TL for comparison.TL oto calculations resulted in TL values that were largely within 5%-10%of TL values calculated withδ^(15) N_(wmt).Our fi ndings show thatδ^(15) N_(oto) is a feasible technique for characterizing the TLs of marine fi sh and can also assist in food web and marine ecosystem studies.展开更多
【目的】采用15N、13C同位素示踪技术,通过对不同施氮量下嘎啦幼苗生长状况及氮、碳分配、利用特性等的研究,以期为苹果生产合理施肥提供依据。【方法】将2年生盆栽嘎啦幼苗进行低、中、高三个氮水平处理,同时进行15N标记。在新梢旺长...【目的】采用15N、13C同位素示踪技术,通过对不同施氮量下嘎啦幼苗生长状况及氮、碳分配、利用特性等的研究,以期为苹果生产合理施肥提供依据。【方法】将2年生盆栽嘎啦幼苗进行低、中、高三个氮水平处理,同时进行15N标记。在新梢旺长初始期、新梢旺长期、新梢缓长期分别进行整株13C标记,72小时后,整株解析为叶、梢、根三部分,进行15N、13C测定。样品全氮用凯氏定氮法测定,15N丰度用ZHT-03质谱计测定。13C丰度用DELTA V Advantage同位素比率质谱仪测定。【结果】1)中、高氮水平的施肥处理可在不同程度上提高整株及叶片干物质量和新梢长度。新梢旺长初始期和新梢缓长期嘎啦幼苗整株干物质量、新梢旺长期叶片干物质分配比率在中、高氮水平处理间差异不显著,中氮水平经济有效。新梢旺长期以后新梢长度以中氮>高氮>低氮,三者间差异性显著,中氮处理有利于新梢生长。2)在新梢旺长初始期,低氮处理植株叶片15N分配率达50%,比其他处理高出13个百分点左右,表明低氮处理更多的氮被叶片所利用,中氮和高氮处理间差异不显著,说明在本试验施氮条件下中氮供应水平已能满足氮素营养需求。3)新梢旺长期和新梢缓长期幼苗13C固定量均以中氮处理最高,新梢旺长初始期3个处理间根系13C分配率中氮>高氮>低氮,表明中氮处理有利于碳同化物在嘎啦幼苗中的分配。4)不同施氮量处理的嘎啦幼苗,15N利用率随施氮水平提高而降低,高氮处理对碳同化物分配没有显著贡献。【结论】低、中、高氮不同处理新梢缓长期碳同化物在各器官间的分配比较均衡,氮素水平不能影响碳同化物的分配。盆栽试验表明,中氮水平在保证营养供应的同时,能够促进新梢生长和树势健壮。展开更多
基金Supported by the National Key Basic Research Development Program of China(973 Program)(No.2015CB453303)the National Science Foundation for Young Scientists of China(No.41606195)。
文摘Fish otolithδ^(15) N(δ^(15) N_(oto))is a demonstrated source of information of dietary history for marine fi sh as it is available iN_(oto)lith archives and sedimentary deposits unlike white muscle tissue(WMT).WMT and stomach content data are insufficient for trophic level(TL)data of past fi shes which is important for the changes of marine fi shery resources over long time scales.To determine the correlation betweenδ^(15) N_(oto) and fi sh WMTδ^(15) N(δ^(15) N_(wmt))and the feasibility of usingδ^(15) N_(oto) in characterizing the TLs of marine fi shes,we conducted nitrogen stable isotope analysis(SIA)in the otolith and WMT of 36 marine fi sh species sampled from the Yellow Sea and northern East China Sea in 2011-2014.Bothδ^(15) N_(oto) andδ^(15) N_(wmt) were analyzed using an elemental analyzer coupled with an isotope ratio mass spectrometer(EA-IRMS).Multiple otoliths were combined to make each otolith measurement and were analyzed as-is without a carbonate dissolution pre-processing step.δ^(15) N_(oto) andδ^(15) N_(wmt) comparisons for species in the Yellow Sea and northern East China Sea are currently lacking and would be helpful for both regional studies and for increasing the number of species for whichδ^(15) N_(oto) andδ^(15) N_(wmt) have been compared.Additionally,to determine the relative accuracy of trophic level calculated usingδ^(15) N_(oto),we compared TL calculated fromδ^(15) N_(oto) to traditional trophic level metrics calculated usingδ^(15) N_(wmt).The results showed a positive and highly signifi cant correlation(R=0.780,P<0.001)betweenδ^(15) N_(oto) andδ^(15) N_(wmt).Trophic level estimation using WMT(TL wmt)and otolith(TL oto)showed congruence in our study,which is not entirely surprising given thatδ^(15) N_(oto) was regressed againstδ^(15) N_(wmt) and the resulting regression coefficient was used to convertδ^(15) N_(oto) toδ^(15) N_(wmt) prior to calculating TL oto.This conversion was required in order to be consistent with previousδ^(15) N_(wmt)-based calculations of TL for comparison.TL oto calculations resulted in TL values that were largely within 5%-10%of TL values calculated withδ^(15) N_(wmt).Our fi ndings show thatδ^(15) N_(oto) is a feasible technique for characterizing the TLs of marine fi sh and can also assist in food web and marine ecosystem studies.
文摘【目的】采用15N、13C同位素示踪技术,通过对不同施氮量下嘎啦幼苗生长状况及氮、碳分配、利用特性等的研究,以期为苹果生产合理施肥提供依据。【方法】将2年生盆栽嘎啦幼苗进行低、中、高三个氮水平处理,同时进行15N标记。在新梢旺长初始期、新梢旺长期、新梢缓长期分别进行整株13C标记,72小时后,整株解析为叶、梢、根三部分,进行15N、13C测定。样品全氮用凯氏定氮法测定,15N丰度用ZHT-03质谱计测定。13C丰度用DELTA V Advantage同位素比率质谱仪测定。【结果】1)中、高氮水平的施肥处理可在不同程度上提高整株及叶片干物质量和新梢长度。新梢旺长初始期和新梢缓长期嘎啦幼苗整株干物质量、新梢旺长期叶片干物质分配比率在中、高氮水平处理间差异不显著,中氮水平经济有效。新梢旺长期以后新梢长度以中氮>高氮>低氮,三者间差异性显著,中氮处理有利于新梢生长。2)在新梢旺长初始期,低氮处理植株叶片15N分配率达50%,比其他处理高出13个百分点左右,表明低氮处理更多的氮被叶片所利用,中氮和高氮处理间差异不显著,说明在本试验施氮条件下中氮供应水平已能满足氮素营养需求。3)新梢旺长期和新梢缓长期幼苗13C固定量均以中氮处理最高,新梢旺长初始期3个处理间根系13C分配率中氮>高氮>低氮,表明中氮处理有利于碳同化物在嘎啦幼苗中的分配。4)不同施氮量处理的嘎啦幼苗,15N利用率随施氮水平提高而降低,高氮处理对碳同化物分配没有显著贡献。【结论】低、中、高氮不同处理新梢缓长期碳同化物在各器官间的分配比较均衡,氮素水平不能影响碳同化物的分配。盆栽试验表明,中氮水平在保证营养供应的同时,能够促进新梢生长和树势健壮。
