conserve water and soil短语⁹⁶⁶⁷⁷⁺⁶ 基本例句 保持水土 Wildly growing- grass and man- planting herbage can increase relative air humidity, decrease the temperature, lower the changes of temperature in a day and/span> conserve water and soil. 果园自然生草、种植牧草后有增加空气相对温度、降低温度、减少温度变幅和防止水土流失的效果。 cnki