Soil Evaporation Characteristics Response To Different Spring Maize Planting Patterns During Growing Season In Northeast

Planting pattern affects soil evaporation in farmland. In this study, maizewas planted in two patterns as follows: Directional and fixed distance fallowrotation (40cm+160cm, KZ), uniform row (65cm, JY). We studied soilevaporation characteristics during growing season under different springmaize planting patterns. Moreover, we studied the effects of addition ofcomminuted straw and straw coverage on soil evaporation characteristics bymicro-lysimeter. The main experiment results are as follows:Compared with JY，though cumulative precipitation supplement of KZwas slightly lower, cumulative soil evaporation of KZ decreased by20.0%.Furthermore, the increase in soil water storage capacity of KZ wassignificantly higher than JY after growing season.Relative soil evaporation intensity of two planting patterns decreasedexponentially with the increase of leaf area index (LAI). There was differencebetween KZ and JY from the jointing stage. The LAI of KZ was greater thanJY, and KZ could maintain maximum LAI for a loner time. LAI was animportant crop fertility indicator for difference in soil evaporation caused bythese two planting patterns. Due to the impact of crop cover, soil temperatureand soil moisture were not the main factors causing soil evaporationdifference of the two planting patterns. However, relatively higher soil temperature promoted soil evaporation.Both cumulative soil evaporation and precipitation supplement undercomminuted straw addition treatments were higher than CK during themeasurement. Soil water storage capacity under comminuted straw additiontreatments after the experiment was lower than initial water storage capacity,but there was no difference between comminuted straw addition treatmentsand CK. There was significant difference between Y4and CK in averagewater content, and average water content of Y4was0.8%higher than CK.Comminuted straw returning did not improve soil retention ability in a shorttime; instead, it would accelerate soil evaporation.Straw cover can restrain the soil evaporation effectively and high strawcoverage treatment had significant effect on soil water evaporation. Theminimum accumulative soil evaporation of40.8mm was found in F4treatment (100%mulching), and there were significant differences betweenF4and other treatments (p<0.05). The soil water storage capacity under thehigh straw coverage treatments was higher than CK. The treatments withstraw mulching were better than adding comminuted straw on inhibiting soilevaporation and water retention ability.