A conjecture on the fertilizer recovery measurement by field experiment
关于肥料利用率的猜想

The measurement of fertilizer recovery either by isotope tracer technique or by field experiment with plots fertilized and unfertilized, both were suspected unreliable and reasons were discussed. Based on some reasonable presumptions, an alternative way of estimating fertilizer recovery by field trials was proposed in this paper, but further examination on it's reliability is needed.