She says farmers should not endlessly work the same soil without putting back some organic matter.

VOA: special.2010.11.09

They are made of organic matter:the same rules, the same laws of chemistry that apply to what makes this laser glow green apply to what makes these photodetectors work.

而是由有机物制作的，同样的规律，它与应用于让激光的光芒变绿,以及使这些光电探测器工作,的化学是一样的规律。

麻省理工公开课 - 固态化学导论课程节选

The study also noted that when tilled soil particles come in contact with air, soil organic matter is lost through the process of oxidation.

VOA: special.2010.09.28