• <menu id="eiqg0"></menu>
  • <menu id="eiqg0"><strong id="eiqg0"></strong></menu>
  • <menu id="eiqg0"><tt id="eiqg0"></tt></menu>
  • <nav id="eiqg0"></nav>
  • 這 Collection 用你的語言不存在, 用...查看: English (en),
    或使用谷歌翻譯:  

    It is easy to say that all a farmer needs to do is add fertilizer and he would harvest enough to feed his family with some left over to sell. However, if he has no resources and has been unable to adequately feed his family he will not be worried about feeding both his and some neighbor’s family. In a Science article, Foley, et al. (2005) have indicated that many modern agricultural practices requiring large applications of chemical fertilizers and the diversion of water to marginal lands are unsustainable. Bunch (2002) has also pointed out that fertilization of tropical soils can even be counterproductive, depending on the crop and the soil.  



    1. 1984-07-01 One aspect of ECHO's ministry is behind the scenes for most of our readers. We help college professors and students in the sciences identify research projects that would be of benefit to the small Third World farmer. Several ideas that could be done at an undergraduate level are written up in...
    2. 1985-01-01 Green manure crops are crops that are [often times in North America] grown to be turned under to increase soil fertility. Leguminous green manure crops ( i.e., those which can make nitrogen fertilizers from atmospheric nitrogen) can offer small-scale Third World farmers a tremendous number of...
    3. 關鍵資源
      2002-01-01 Acidification of soil is a natural process with major ramifications on plant growth. As soils become more acid, particularly when the pH drops below 4.5, it becomes increasingly difficult to produce food crops. As soil pH declines, the supply of most plant nutrients decreases while aluminum and a...
    4. 關鍵資源
      2009-01-20 All plants need certain mineral elements for proper growth, development, and maintenance. The basic structure of all organisms is built of carbon (C), oxygen (O) and hydrogen (H). Plants obtain these elements from water (H2O) in the soil and carbon dioxide (CO2) in the air, so no input is...
    5. 2010-08-01 Worm or vermiculture is a useful technique for recycling kitchen and livestock wastes into a rich organic fertilizer, for producing high-protein feed for poultry and initiating a lucrative business selling worms and worm castings for the small farm. Worms are invaluable partners in building the...
    6. 關鍵資源 2013-06-01 Rick Burnette wrote an article for Issue 7(July 2010) of ECHO Asia Notes, titled “Charcoal Production in 200-Liter Horizontal Drum Kilns.” My article takes the charring process a step further by exploring the rapidly re-emerging world of biochar. Biochar is a form of charcoal, produced through...
    7. 關鍵資源 2014-01-01 In order to achieve high levels of agricultural productivity in the tropics at the lowest possible economic and ecological costs, we need to properly understand the relationship between nutrients in the soil and crop productivity. For this to happen, the current understanding needs to change. The...
    8. 2016-08-17 Farmers and gardeners in semi-arid and arid regions of the world face two associated but separate problems, which limit the crops they can grow and the yield of these crops. The underlying problem is lack of rainfall needed for growing plants. The second is accumulation of salts in the root zone....
    精选六肖资料必中特