Large seasonal swings in leaf area of Amazon rainforests

被引：345

作者：

Myneni, Ranga B.

Yang, Wenze

Nemani, Ramakrishna R.

Huete, Alfredo R.

Dickinson, Robert E.

Knyazikhin, Yuri

Didan, Kamel

Fu, Rong

Juarez, Robinson I. Negron

Saatchi, Sasan S.

Hashimoto, Hirofumi

Ichii, Kazuhito

Shabanov, Nikolay V.

Tan, Bin

Ratana, Piyachat

Privette, Jeffrey L.

Morisette, Jeffrey T.

Vermote, Eric F.

Roy, David P.

Wolfe, Robert E.

Friedl, Mark A.

Running, Steven W.

Votava, Petr

El-Saleous, Nazmi

Devadiga, Sadashiva

Su, Yin

Salomonson, Vincent V.

机构：

[1] Boston Univ, Dept Geog & Environm, Boston, MA 02215 USA

[2] NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Moffett Field, CA 94035 USA

[3] Univ Arizona, Dept Soil Water & Environm Sci, Tucson, AZ 85721 USA

[4] Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA

[5] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA

[6] Calif State Univ Monterey Bay, Moffett Field, CA 94035 USA

[7] NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Moffett Field, CA 94035 USA

[8] San Jose State Univ, Moffett Field, CA 94035 USA

[9] NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Moffett Field, CA 94035 USA

[10] NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA

[11] NASA, Goddard Space Flight Ctr, Terr Informat Syst Branch, Greenbelt, MD 20771 USA

[12] Univ Maryland, Dept Geog, College Pk, MD 20742 USA

[13] S Dakota State Univ, Geog Informat Sci Ctr Excellence, Brookings, SD 57007 USA

[14] NASA, Goddard Space Flight Ctr, Raytheon Technol Serv Corp, Greenbelt, MD 20771 USA

[15] Univ Montana, Sch Forestry, Missoula, MT 59812 USA

[16] NASA, Goddard Space Flight Ctr, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA

[17] Univ Utah, Dept Geog & Meteorol, Salt Lake City, UT 84112 USA

来源：

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | 2007年 / 104卷 / 12期

关键词：

remote sensing; tropical forests phenology; vegetation climate interaction; TROPICAL FOREST; PHENOLOGY; GROWTH; TREE; CONSEQUENCES; DROUGHT; WATER; CO2;

D O I：

10.1073/pnas.0611338104

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Despite early speculation to the contrary, all tropical forests studied to date display seasonal variations in the presence of new leaves, flowers, and fruits. Past studies were focused on the timing of phenological events and their cues but not on the accompanying changes in leaf area that regulate vegetation-atmosphere exchanges of energy, momentum, and mass. Here we report, from analysis of 5 years of recent satellite data, seasonal swings in green leaf area of approximate to 25% in a majority of the Amazon rainforests. This seasonal cycle is timed to the seasonality of solar radiation in a manner that is suggestive of anticipatory and opportunistic patterns of net leaf flushing during the early to mid part of the light-rich dry season and net leaf abscission during the cloudy wet season. These seasonal swings in leaf area may be critical to initiation of the transition from dry to wet season, seasonal carbon balance between photosynthetic gains and respiratory losses, and litterfall nutrient cycling in moist tropical forests.

引用

页码：4820 / 4823

页数：4