Professor lin bao has indicated that short - term experiments showing the reliance on n fertilizer were initially effective , however as time progressed evidence of nutrient resource depletion became clear 林葆教授指出,長期試驗表明了對氮肥的依賴性在短期內就是有效的,但隨著時間的增長養分資源耗竭的證據越來越明顯。