单词：soil organic matter fractions
单词：soil organic matter fractions 相关文章
The rock called sandstone is made up of a great many grains of sand. The beating of the rain on this rock washes the grains apart, and so the hard sandstone slowly changes into loose sand. 砂岩主要由大量沙粒组成。当雨水打下来的时候
英国学生科学读本
AGRICULTURE REPORT - Don't Know Much About Mulch?By George Grow Broadcast: Tuesday, January 24, 2006 I'm Faith Lapidus with the VOA Special English Agriculture Report. Mulch is important to farmers. M
2006年慢速英语（一）月
This is the VOA Special English Agriculture Report. Earlier this month, Michelle Obama and twenty-three schoolchildren helped prepare the ground for an organic vegetable garden on the South Lawn of the White House. The first lady showed the young ga
VOA慢速英语2009年（三）月
This is the VOA Special English Agriculture Report. Earlier this month, Michelle Obama and twenty-three schoolchildren helped prepare the ground for an organic vegetable garden on the South Lawn of the White House. The first lady showed the young gar
2010年慢速英语(三)月
Podcast is sponsored from the people of American Chemistry, who provide the plastics, medicines, and innovations that make life modern. Learn more at americanchemistry. com. This is Scientific American's 60-Second Science, Im Karen Hopkin. This will
Scientific American(七)月
(man) Today I want to discuss fossil fuels such as coat, oil, and natural gas. The term fossil fuel refers to the trapped remains of plants and animals in sedimentary rock. You see, living plants trap energy from the sun by the process of photosynth
托福听力短文
The subject of many people's conversations is the flu. Everybody is talking about it. The clinics and hospitals are full of people who have flu symptoms, and supermarkets have shelves full of medicines, tissues(1), and vitamin powders. I've been luck
英语博客 A cup of English
In side-by-side plots of strawberries grown organically or conventionally, the organic berries had more vitamin C and the soil was more biologically active. Molly Webster reports 通过对用有机方式培育的草莓和用传统方式培育的草莓进
60秒科学
By Mario Ritter Broadcast: September 9, 2003 This is Steve Ember with the VOA Special English Agriculture Report. For many people, growing crops on a small piece of land is not a business. For them, a
VOA2003（下）-农业与经济
It seemed like a good ideabecause rivers and ponds in Bangladesh were contaminated with bacteria, Bangladeshis switched to wells. But soon after, in the early 80s, researchers realized those wells were harming Bangladeshis with a new poisonarsenic. T
Scientific American(十一)月
[00:05.49]Reading [00:08.36]A PIONEER FOR ALL PEOPLE [00:12.43]He wants everyone to call him a farmer,for that's how he regards himself. [00:19.28]Although he is one of China's most famous scientists, [00:24.45]Yuan Longping works the land to do his
高中英语人教版必修
AGRICULTURE REPORT – June 25, 2002: Organic Farming Study By George Grow (Photo -Scott Bauer) This is the VOA Special English Agriculture Report. Agricultural scientists in Switzerland have demonstr
农业与发展
Agriculture Report - Using Charcoal to Make Soil Into Black Gold Scientists show a way to improve soil quality with ''biochar.'' Transcript of radio broadcast: 05 May 2008 This is the VOA Special English Agriculture Report. The dense Amazon rainfore
VOA慢速英语2008年（五）月
Why mulching is one of the best things to do for plants. Transcript of radio broadcast: 14 July 2008 This is the VOA Special English Agriculture Report. Mulch is spread in a city park in Atlanta, Georgia Mulch is important to farmers. Mulch is a pro
VOA慢速英语2008年（七）月
This is the VOA Special English Agriculture Report. Soil naturally contains harmless amounts of lead, along with other metals. Because of pollution, however, the amounts are higher the closer you get to cities and towns. But experts say this should
VOA慢速英语2009年（六）月
This is the VOA Special English Agriculture Report. Spreading mulch Mulch is important to farmers. Mulch is a protective cover of material that is spread on top of soil. It is usually made out of organic material, like crop waste. Farmers may keep t
VOA慢速英语2007年（四）月
AGRICULTURE REPORT - Study Points to Risk in Common Method of Enriching Soil By Jerilyn Watson / Broadcast: Mon, 12 Nov 2007 16:00:00 UTC This is the VOA Special English Agriculture Report. For more than half a century, many farmers worldwide have a
VOA慢速英语2007年（十一）月
AGRICULTURE REPORT - September 3, 2002: Mulch By George Grow This is Bill White with the VOA Special English AGRICULTURE REPORT. Mulching is one of the best things people can do for their plants. Mulc
农业与发展
AGRICULTURE REPORT - Compost: an Organic Way to Better Soil and Crops By Gary Garriott Broadcast: Tuesday, July 05, 2005 I'm Gwen Outen with the VOA Special English Agriculture Report. Many farmers im
农业与发展
Listen to the dialogues and fill in T for True, F for False. 英语对话1 A:Does this plant need a lot of sunlight? B:Yes, it's a dessert plant. 英语对话2 A:Should this plant be watered everyday? B:No. twice a week will be enough. 英语对话3
英语听力练习题