作业,老师给的都是全英版的论文,需要翻译后再研究。
已经挑了最短的一篇了,还是弄不明白,天还巨热,还有很多别的事儿要忙,很抓狂啊!!
很急,明天就要。希望高手帮忙啊~谢谢啦!!
SANTA CRUZ, GALÁPAGOS ISLANDS—Rachel
Atkinson hops like a Darwin finch from one
volcanic outcropping to the next, then plunges
into ankle-deep mud. Squishing as she walks,
the botanist with the Charles Darwin Research
Station homes in on the ailing invaders: blackberry,
passion fruit, and quinine bushes clustered
near Santa Cruz Island’s last shrubby
stands of Scalesia trees. Atkinson smiles in
approval. One more blast of herbicide ought to
prevent the aliens from regrowing and give the
Scalesia a shot at survival after all.
Atkinson’s search-and-destroy mission is
part of an ambitious 6-year, $18 million
Global Environment Facility (GEF) effort by
the station and Galápagos National Park to
turn the tide against invasive species in the
Galápagos Islands, the fragile crucible of life
that inspired Charles Darwin to formulate his
theory of evolution 150 years ago. The GEF
grant runs until next year, but the results so far
are stunning. A survey here last month has
confirmed that enemy number one—the feral
goat—has been virtually wiped off Isabela,
Santiago, and Pinta islands. All told, some
140,000 feral goats were slain in 5 years of the
GEF-funded Project Isabela, the largest eradication
project ever undertaken. “A great battle
has been won here,” says Victor Carrion, subdirector
of the park.
Although one bane has been eliminated,
others are at large. In northern Isabela, rats
have ravaged the last two nesting sites of
mangrove finches, estimated at fewer than
100. And both rats and feral cats have decimated
a subspecies of marine iguana
(Amblyrhynchus cristatus albemarlensis)
endemic to Isabela, prompting the World
Conservation Union to add it to its vulnerable
list in 2004. Rangers have set out traps and
poison for Isabela’s rats and are plotting eradication
campaigns on Floreana and Santiago
islands. An effort to poison feral cats will
commence next year.
The Galápagos have been under siege ever
since pirates and whalers began visiting the
archipelago in the 1700s and leaving behind
goats, pigs, and other animals as a living larder
for future visits. But it wasn’t until the late
1980s that the goat population suddenly started
booming, possibly due to El Niño–driven
changes in vegetation patterns. Godfrey
Merlen, a Galápagos native and director of
WildAid, says he saw “two or three” goats on
the upper flanks of Isabela’s Alcedo volcano in
1992. When he returned 3 years later, he saw
hundreds. “It was total chaos,” Merlen says.
The goats had denuded the once-lush terrain,
transforming brush and cloud forests into
patchy grassland.
还有~
Ecological shock waves rippled across
Isabela. The highlands had served as a safe
haven for species such as the giant tortoise.
“We saw many more tortoises falling into the
volcanic craters,” trying to reach feeding
grounds or because of erosion, says Carrion.
“Being a baby tortoise is hard enough,” adds
Thomas Fritts, past president of the Charles
Darwin Foundation. “Competing with voracious
herbivores is an extra challenge.”
Park rangers quickly cottoned on and
started slaying the goats in 1995. They had
eradicated a much smaller population from
Española Island in the 1970s. But with tens of
thousands of goats on northern Isabela alone,
officials knew they needed a novel approach.
In 2000, GEF agreed to bankroll an antigoat
operation as long as it was part of an effort
to tackle invasive species across the board
(Science, 27 July 2001, p. 590).