The gas exchange of an oak stand in the southeastern forest steppe was examined under variable moisture availability and ambient temperature. For several years the CO2 exchange was measured concurrently on leafy shoots and nonphotosynthesizing organs (trunks, branches, and roots) of oak trees (Quercus robur L.). The root respiration was found to decrease upon moisture limitation. The trunk respiration was promoted by the increase in moisture deficiency until the predawn leaf water potential (PLWP) reduced to −1.5 MPa, and respiration declined gradually upon further reduction in moisture availability. The proportion between net and gross primary productivities (NPP/GPP) also depended on moisture availability. The NPP/GPP ratio was 0.49 under optimal conditions at PLWP of −0.5 MPa, but it approached zero when PLWP lowered to −1.5 MPa. Upon drought conditions, which are typical of southeastern steppe in the second half of summer, the oak stand lost its CO2 sink capacity and became the CO2 source.
Russian Journal of Plant Physiology – Springer Journals
Published: Nov 6, 2009
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera