?? ?????75%??????????

????:????????700??:???????

?????????????7???????????2??(?? ?????????????)????????????????????“?”?7??2?????????????,????,?????????????????6?30??7??????2??,????????????????????,?????????????,????????????2?15?,????????75%??

?????????6?????????????30??????????,????????? ?

??,7?1????????????????6??2?????6?????,??????,????????????????????????????????????????????????????????????????????????????????????????????????,?????????:??139.7?????????105.4?????99.0???

????????????????7?????2?15??0-20cm?,?75%?????,25%??????,?????

??,?????????????,??????????????????,??,??,?????????

??,?????????10?,?????,???????,7?3?6?,???????????,????;7?8???,????;9?????????13????????,??,??????????????????14?????????????????15??????????????,??,???????????????????????????????????,???

?????,??????????????:??,??,?,?,?,????????????????????????????????,????????????????(?????????)

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