内容摘要：Guam has been an important military outpost since World War II, dominated by Andersen Air Force Base and its many outlying installations. There also is a robust naval and marine presence with about 30% of the territory’s land occupied by U.S. military installations.

Guam has been an important military outpost since World War II, dominated by Andersen Air Force Base and its many outlying installations. There also is a robust naval and marine presence with about 30% of the territory’s land occupied by U.S. military installations.

To mimic stress from drought, the project, located in the, assembled about 6,000 transparent plastic rectangular panels across one hectare (2.5 acres), diverting around 50% of the rainfall from the forest floor. They were set 1 meter above ground (3.3 ft) on the sides to 4 meters (13.1 ft) above ground in the center. The water was funneled into gutters and channeled through trenches dug around the plot’s perimeter.

Next to it, an identical plot was left untouched to serve as a control. In both areas, instruments were attached to trees, placed on the ground and buried to measure soil moisture, air temperature, tree growth, sap flow and root development, among other data. Two metal towers sit above each plot.In each tower, NASA radars measure how much water is in the plants, which helps researchers understand overall forest stress. The data is sent to the space agency’s Jet Propulsion Laboratory in California, where it is processed.“The forest initially appeared to be resistant to the drought,” said Lucy Rowland, an ecology professor at the University of Exeter.

That began to change about 8 years in, however. “We saw a really big decline in biomass, big losses and mortality of the largest trees,” said Rowland.This resulted in the loss of approximately 40% of the total weight of the vegetation and the carbon stored within it from the plot. The main findings were detailed in

published in May in the journal Nature Ecology & Evolution. It shows that during the years of vegetation loss, the rainforest shifted from a carbon sink, that is, a storer of carbon dioxide, to a carbon emitter, before eventually stabilizing.

There was one piece of good news: the decades-long drought didn’t turn the rainforest into a savanna, or large grassy plain, as earlier model-based studies had predicted.2¼ teaspoons instant yeast

¾ teaspoon table salt½ teaspoon ground cinnamon

¼ teaspoon ground allspice¼ teaspoon freshly grated nutmeg