Background:Most North American temperate forests are plantation or regrowth forests,which are actively *** forests are in different stages of their growth cycles and their ability to sequester atmospheric carbon is af...
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Background:Most North American temperate forests are plantation or regrowth forests,which are actively *** forests are in different stages of their growth cycles and their ability to sequester atmospheric carbon is affected by extreme weather *** this study,the impact of heat and drought events on carbon sequestration in an age‑sequence(80,45,and 17 years as of 2019)of eastern white pine(Pinus strobus L.)forests in southern Ontario,Canada was examined using eddy covariance flux measurements from 2003 to ***:Over the 17‑year study period,the mean annual values of net ecosystem productivity(NEP)were 180±96,538±177 and 64±165 g C m^(–2)yr^(–1)in the 80‑,45‑and 17‑year‑old stands,respectively,with the highest annual carbon sequestration rate observed in the 45‑year‑old *** found that air temperature(Ta)was the dominant control on NEP in all three different‑aged stands and drought,which was a limiting factor for both gross ecosystem productivity(GEP)and ecosystems respiration(RE),had a smaller impact on ***,the simultaneous occurrence of heat and drought events during the early growing seasons or over the consecutive years had a significant negative impact on annual NEP in all three *** observed a similar trend of NEP decline in all three stands over three consecutive years that experienced extreme weather events,with 2016 being a hot and dry,2017 being a dry,and 2018 being a hot *** youngest stand became a net source of carbon for all three of these years and the oldest stand became a small source of carbon for the first time in 2018 since observations started in ***,in 2019,all three stands reverted to annual net carbon ***:Our study results indicate that the timing,frequency and concurrent or consecutive occurrence of extreme weather events may have significant implications for carbon sequestration in temperate conifer forests in Eastern North *** study is one of few globally available t
The report sets out to summarize the past and current situation regarding the practice of biologicalcontrol inrelationtothe use and exchange of genetic resources relevant for *** considers the twomain categories of bi...
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The report sets out to summarize the past and current situation regarding the practice of biologicalcontrol inrelationtothe use and exchange of genetic resources relevant for *** considers the twomain categories of biological control:classical and *** access to BCAs for use inanother country imposes no risk of liability to the source *** scientific knowledge abouthabitats,fauna andflora,can be
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