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

Decrease in Shark Population Harms Ocean 1)Ecosystems

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(357) / 评论(0)

VOA2003（上）-科技先知

VOA标准英语2012--Report: Ecosystems More Stressed Than Ever

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(441) / 评论(0)

VOA标准英语2012年(十二月)

科学美国人60秒 SSS Waste Amphetamines Alter Underwater Ecosystems

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(295) / 评论(0)

2016年Scientific American(八)月

NPR 2010-11-09

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(347) / 评论(0)

2010年NPR美国国家公共电台11月

Lonely bug

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(461) / 评论(0)

六分钟英语

Severe Drought, Wildfires Threaten Water Resources

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(448) / 评论(0)

VOA标准英语2012年(一月)

VOA慢速英语20061114a

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(309) / 评论(0)

2006年慢速英语(十一)月

雅思范文：学童用功

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(419) / 评论(0)

雅思英语

GRE试题一(1)

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(375) / 评论(0)

实用英语

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加州语文教材 G3 V3 Ecosystems in Balance 07

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加州语文教材 G3 V3 Ecosystems in Balance 05

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加州语文教材 G3 V3 Ecosystems in Balance 01

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a deed of covenant

aircraft-pavement classification number system (acn-pcn)