音标:[ˈekəʊˌsɪstəmz] ;
n. <生>生态系统( ecosystem的复数形式 )
n. a system formed by the interaction of a community of organisms with their physical environment

Broadcast: Jan 16, 2003 Experts say one of the world's most feared, but misunderstood, creatures is under 2) assault by fishermen. A new study of all types of sharks finds that there are fewer of them

发表于:2018-12-08 / 阅读(84) / 评论(0) 分类 VOA2003(上)-科技先知

Report: Ecosystems More Stressed Than Ever When Super Storm Sandy ravaged the U.S. East Coast and inundated New York City in late October, many wondered if such extreme weather events might be linked to climate change, the gradual warming of the plan

发表于:2018-12-08 / 阅读(172) / 评论(0) 分类 VOA标准英语2012年(十二月)

Last week, tens of thousands of gallons of sewage gushed into urban streams in Baltimore, because of leaky pipes and flooding rains. And when that happens, it's not just organic matter and microbes that get flushed into aquatic habitats. It's drug re

发表于:2018-12-24 / 阅读(87) / 评论(0) 分类 2016年Scientific American(八)月

From NPR News in Washington, I'm Lakshmi Singh. A radical Sunni Muslim cleric born in the US is urging religious scholars to promote holy war against American and Israeli interests in the Middle East. NPR's Soraya Sarhaddi Nelson is in Cairo and repo

发表于:2019-01-08 / 阅读(90) / 评论(0) 分类 2010年NPR美国国家公共电台11月

Lonely bug NB: This is not an accurate word-for-word transcript Dima:Hello and welcome to this edition of 6 Minute English with me, Dima Kostenko Rebecca: and me, Rebecca Byrne. Dima:Today we'll have some useful words and phrases used in science and

发表于:2019-01-10 / 阅读(121) / 评论(0) 分类 六分钟英语

Severe Drought, Wildfires Threaten Water Resources This is Valles Caldera. Actually, it's the giant mouth of a dormant super volcano that last erupted 40,000 years ago. In the millennia since then, the terrain developed high-elevation forests, of abu

发表于:2019-01-13 / 阅读(179) / 评论(0) 分类 VOA标准英语2012年(一月)

AGRICULTURE REPORT - Study Warns of Risk to Seafood Supplies in World's OceansBy Jerilyn Watson Broadcast: Tuesday, November 14, 2006 This is the VOA Special English Agriculture Report. A study has wa

发表于:2019-01-30 / 阅读(99) / 评论(0) 分类 2006年慢速英语(十一)月

Topic: In some countries, parents expect children to spend long time studying both in and after school, and have less free time. Task: (You may spend 40 minutes on this task, and write a minimum of 250 words) Do you think it has the positive or negat

发表于:2019-02-09 / 阅读(128) / 评论(0) 分类 雅思英语

SECTION 1 Time - 30 minutes 38 Questions Directions: Each sentence below has one or two blanks, each blank indicating that something has been omitted. Beneath the sentence are five lettered words or s

发表于:2019-02-13 / 阅读(101) / 评论(0) 分类 实用英语

图片1 图片2

发表于:2019-02-20 / 阅读(176) / 评论(0) 分类 加州语文教材California Treasures G3
学英语单词
achromatosis
acquisition cession
agate bearing
al-hasan ibn al-haythams
Alpinia densibracteata
amarjits
aptotes
assessment of time preference
attenazio
AURPO
autoinducible enzyme
available space list
aviling
bala
be said to
be sparing of oneself
bipolaron
bird-songs
boiling water
Bouvet Fracture Zone
capping shutter
clearer belt
clunged
commissorial
continuous current rating
coprime
costusroots
Cryptochilum
DDR5
Druzbice
dual dimensioning
earth's polar radius
eke out one's livelihood
El Viso del Alcor
electric press
electrical resistance alloys
enterovaccine
erythrocytic segment
evaporating heating surface
feeldevice
fiato
finder screen
forward welding
g.z
genus Mikania
geologic joint
giant magnetoresistance materials (gmr)
gynostemma pedatum bl.
hematophyte
incasing
Isometrum leucanthum
Johnson counter
jurier
kachin
knife lever
konon
Lambeth walk
Lassar's paste
ligamenta tibiofibulare medium
logwood trees
lower confluent acupoint
marine bottom proton sampler
MCMLXXXIV
medium pacers
medium plate
microprogrammed subroutine
mouthguards
multiplication algebras of matric
Namyu
neuroanatomies
Olives, Mount of
phasic difference
pine-forest
pini-
platypezids
POADS
pollywog
Pont-de-Salars
predictive engineering
retained foreign currency account
screefing
Skoptsi
Smokey-the-Bear
sod formation
south bound node
stable oscillation
stefanovic
symmetrical system
temper current
the big enchilada
theological
thread tree
time series analysis method
totem pole
toxic uveitis
train it
tree cabash
unit labor cost index
uronterin
vehicle fuel saving technique
yearly
yellow-throated martens