CO{sub 2} exchange in the Hudson Bay lowlands: Community characteristics and multispectral reflectance properties

Journal Article · Thu Jan 20 04:00:00 EST 1994 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/93JD01833· OSTI ID:81547

Whiting, G J ^[1]

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1. Christopher Newport Univ., Newport News, VA (United States)

Net ecosystem CO{sub 2} exchange was measured during the 1990 growing season (June to August) along a transect starting 10 km inland from James Bay and extending 100 km interior to Kinosheo Lake, Ontario. Sites were chosen in three distinct areas: a coastal fen, an interior fen, and a bog. For the most productive sites in the bog, net daily uptake rates reached a maximum of 2.5 g C-CO{sub 2} m{sup {minus}2} d{sup {minus}1} with an area-weighted exchange of 0.3 g C-CO{sub 2} m{sup {minus}2} d{sup {minus}1} near midsummer. The interior fen was less productive on a daily basis with a net maximum uptake of 0.5 g C-CO{sub 2} m{sup {minus}2} d{sup {minus}1} and with corresponding area-weighted uptake of 0.1 g C-CO{sub 2} m{sup {minus}2} d{sup {minus}1} during midsummer. Early and late season release of carbon to the atmosphere resulted in a net loss of 21 g C-CO{sub 2} m{sup {minus}2} over the growing season from this site. The coastal fen was the most productive site with uptake rates peaking near 1.7 g C-CO{sub 2} m{sup {minus}2} d{sup {minus}1} which corresponded to an area-weighted uptake of 0.8 g C-CO{sub 2} m{sup {minus}2} d{sup {minus}1} during midsummer and an estimated net uptake of 6 g C-CO{sub 2} m{sup {minus}2} for the growing season. These properties were related to exchange rates with the goal of examining the potential for satellite remote sensing to monitor biosphere/atmosphere CO{sub 2} exchange in this biome. The normalized difference vegetation index (NDVI) computed from surface reflectance was correlated with net CO{sub 2} exchange for all site with the exception of areas with large proportions of Sphagnum moss cover. These mosses have greater near-infrared reflectance than typical surrounding vegetation and may require special adjustment for regional exchange/remote sensing applications. 41 refs., 9 figs., 3 tabs.

• OSTI ID: 81547
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: D1 Vol. 99; ISSN JGREA2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CARBON DIOXIDE
CARBON SOURCES
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
ECOSYSTEMS
ENVIRONMENTAL TRANSPORT
HUDSON RIVER
OPTICAL PROPERTIES
RADIOMETERS
REMOTE SENSING
WETLANDS