Apparent Photosynthesis in Some Conifers During Winter

Freeland, R. O.

doi:10.1104/pp.19.2.179

Cited by 44 publications

(22 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…α significantly correlated with water condition in the roots zone in the cold and dry winter. This shows that there was maintenance photosynthesis in winter and validated the Freeland's report on photosynthesis by some conifers below −6℃ even down to −40℃ [35] .…”

Section: Relationships Between Ecosystem Carbon Metabolism and Envirosupporting

confidence: 67%

Seasonal and annual variation of CO2 flux above a broad-leaved Korean pine mixed forest

Zhang

Han

et al. 2006

SCI CHINA SER D

View full text Add to dashboard Cite

Long-term measurement of carbon metabolism of old-growth forests is critical to predict their behaviors and to reduce the uncertainties of carbon accounting under changing climate. Eddy covariance technology was applied to investigate the long-term carbon exchange over a 200 year-old Chinese broad-leaved Korean pine mixed forest in the Changbai Mountains (128°28′E and 42°24′N, Jilin Province, P. R. China) since August 2002. On the data obtained with open-path eddy covariance system and CO 2 profile measurement system from Jan. 2003 to Dec. 2004, this paper reports (i) annual and seasonal variation of F NEE , F GPP and R E ; (ii) regulation of environmental factors on phase and amplitude of ecosystem CO 2 uptake and release Corrections due to storage and friction velocity were applied to the eddy carbon flux.L AI and soil temperature determined the seasonal and annual dynamics of F GPP and R E separately. V PD and air temperature regulated ecosystem photosynthesis at finer scales in growing seasons. Water condition at the root zone exerted a significant influence on ecosystem maintenance carbon metabolism of this forest in winter.The forest was a net sink of atmospheric CO 2 and sequestered −449 g C·m −2 during the study period; −278 and −171 gC·m −2 for 2003 and 2004 respectively. F GPP and F RE over 2003 and 2004 were −1332, −1294 g C·m −2. and 1054, 1124 g C·m -2 respectively. This study shows that old-growth forest can be a strong net carbon sink of atmospheric CO 2 .There was significant seasonal and annual variation in carbon metabolism. In winter, there was weak photosynthesis while the ecosystem emitted CO 2 . Carbon exchanges were active in spring and fall but contributed little to carbon sequestration on an annual scale. The summer is the most significant season as far as ecosystem carbon balance is concerned. The 90 days of summer contributed 66.9, 68.9% of F GPP , and 60.4, 62.1% of R E of the entire year.

show abstract

Section: Relationships Between Ecosystem Carbon Metabolism and Envirosupporting

confidence: 67%

Seasonal and annual variation of CO2 flux above a broad-leaved Korean pine mixed forest

Zhang

Han

et al. 2006

SCI CHINA SER D

View full text Add to dashboard Cite

show abstract

“…It is well-established that enzymes may function at subzero temperatures (13) and that photosynthesis and dry-weight increases may occur in conifers during the winter period (7,14,17,31,33,42,48). Moreover, Durzan (12), working in the Canadian climate, has demonstrated the free amino acid pool of the apices and needles of Picea to be in a dynamic state during midwinter.…”

Section: Discussionmentioning

confidence: 96%

Apparent auxin production and transport during winter in the nongrowing pine tree

Savidge¹,

Wareing²

1982

Can. J. Bot.

View full text Add to dashboard Cite

SAVIDGE, R. A., and P. F. WAREING. 1982. Apparent auxin production and transport during winter in the nongrowing pine tree.Can. J. Bot. 60: 681-691.Endogenous indol-3yl acetic acid (IAA) was characterized by combined gas chromatography -mass spectroscopy (GC-MS) in inactive cambia of Pinus contorta Dougl. and Larix decidua Mill. during winter, and IAA levels were estimated by GC-MS in buds, needles, and the tissues comprising the inactive cambial region of P. contorta during late autumn and winter. Supplementary IAA estimates were obtained for cambia of Acer pseudoplatanus L., L. decidua, Populus X canadensis 'Robusta,' and Quercus robur L. IAA levels in cambial tissue of lodgepole pine were higher than those in similar-aged tissue of hardwoods throughout the winter.Both winter disbudding and defoliating treatments reduced levels of endogenous IAA in the cambial region of lodgepole pine. Moreover, exogenous [14C]IA~ and [14~]sucrose were transported downward in the stem during winter. Microscopy suggested functional sieve cells to be present during winter, and the moisture content of the cambial region of lodgepole pine was more than twice that of overwintering hardwoods.Thus, the vascular cambium of P. contorta probably is not dependent upon a supply of IAA from extending shoots and growing needles for its reactivation in spring. The findings also suggest that IAA production and export from metabolically active buds and mature needles may occur during winter.

show abstract

“…Production rates vary considerably from day to day and from hour to hour within the day for each species of plant in the ecosystem. Freeland ( 1944), working with Pinus sylvestris, P. nigra, and Picea mariana. In Heinicke and Childers' study as in other studies carried out in humid areas (Saeki andNomoto 1958, Kramer andKozlowski 1960), daily and seasonal variation in productivity were highly correlated with light intensity and temperature, July and August being the most productive months.…”

Section: Seasonal Variation In Productivitymentioning

confidence: 99%

Primary Production in Grazed and Ungrazed Desert Communities of Eastern Idaho

Pearson¹

1965

Ecology

View full text Add to dashboard Cite

The harvest method; was employed to study primary production in two plant communities, one of which had heen continuously grazed for about 70 years while the other had been protected from grazing for a period of 11 years. Exclosures were constructed around both study areas to protect them from livestock grazing during the 2 years of the study.There was 45% more top growth in the protected area but only 68% as much root mass; consequently, average annual net production was at least 12% greater in the grazed area. Irrigation with 9 em water increased top-growth yield 41.4%. Although over 30 species of plants were present in each community, two species contributed over half of the annual production in both areas. In the protected community 65% and in the grazed community 80% of the plant mass was underground. Proportion of plant mass underground ranged from 55% to over 98% in individual plants excavated whole. Following harvesting of the tops, dry weight of the roots decreased 1.6% during the first week, 22.1% during the first month, and 31.3o/o during the first 8 months. To measure seasonal trends in productivity, six plots, each 1 m2 in area, were harvested every week during two growing seasons. Artemisia tridentata, the principal shrub present, seemed to be most productive during the fall and early spring while Stipa comata, the principal grass, was most productive during late spring and early summer.

show abstract

Apparent Photosynthesis in Some Conifers During Winter

Cited by 44 publications

References 5 publications

Seasonal and annual variation of CO2 flux above a broad-leaved Korean pine mixed forest

Seasonal and annual variation of CO2 flux above a broad-leaved Korean pine mixed forest

Apparent auxin production and transport during winter in the nongrowing pine tree

Primary Production in Grazed and Ungrazed Desert Communities of Eastern Idaho

Contact Info

Product

Resources

About