Abstract:The time and space regular changes of light intensity,wind speed,temperature,relative humidity with the mulching of paspalum notatum flugge in orchard are analysed.Light in peach orchard is twice more than citrus orchard at noon in winter.The wind speed is three or four times more at fourteen in winter.The highest surface temperature with mulch is 20.0℃ lower than uncovered soil in row interval,10.0℃ lower in plants interval.The temperature with mulch in winter is 2.4℃ higher than uncovered soil in citrus orchard,1.1℃ higher in peach orchard.The effect of temperature descend in summer and the effect of temperature keeping is very manifest.The photic ratio in citrus orchard changed with height is the relation of exponent,and the wind speed changed with the shoot height is the relation of second curve.Temperature in uncovered soil descends with the ascent of hight,but the soil temperature with mulch has the opposite result.However,the relative humidity is low in morning and evening,and high at noon,the relative humidity in summer is higher than in winter.The relative humidity in different treatments ascends sometimes or descends sometimes with the change of height.