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本文在小麦‖早春玉米/夏玉米超高产种植体系下,研究了套作夏玉米根系数量与活性的空间分布及变化规律,主要结果:(1)套作夏玉米于开花期达到最大根深160cm左右,且120～160cm深层根量持续增长至蜡熟末期。(2)根系数量呈上多下少的“T”型分布,0～20、20～80、80～120及120～160cm土层分别为根系高密度区、中密度区、低密度区和稀密度区。0～20、20～40及40～80cm土层根量密度大致于开花灌浆期达到最大值,之后呈下降趋势;80～120cm及120～160cm土层分别于灌浆期和蜡熟末期达最大;0～160cm整体根量密度以灌浆期为最大。(3)根系活性在土体中与数量相反呈倒“T”型分布。随生育进程推进,不同土层根系活性呈小→大→小变化,并且根系最高活性位点呈下移趋势,拔节期以20～40cm土层最高、大口期和开花期以80～120cm最高、灌浆期和蜡熟末期以120～160cm最高。0～160cm整体根系平均以大口期活性最高。(4)根系TTC还原总量在土体中呈上高下低的“T”型分布,根据TTC还原总量和总量密度高低,0～20、20～120和120～160cm土层分别为高量高密度区、中量中密度区和低量低密度区。从动态看,120cm以上各土层根系TTC还原总量及总量密度于花期达最大值,120～160cm深层土壤于灌浆期达最大值。0～160cm整体根系的TTC还原总量及总量密度?
The main results were as follows: (1) The maximal root depth and depth of intercropping summer maize reached about 160cm at flowering stage under the wheat ‖ early spring maize / summer maize super-high-yielding planting system. , And 120-160 cm deep roots continued to grow to the wax maturity stage. (2) The number of root system was mostly “T ” type. The soil layers of 0-20, 20-80, 80-120 and 120-160cm were root high density, middle density and low density And dilute density area. The root densities of 0-20, 20-40 and 40-80 cm soil layers reached the maximum at flowering and filling stage and then decreased. The soil layers of 80-120 cm and 120-160 cm reached the maximum at grain filling and wax maturity, respectively. The total root density of 0 ~ 160cm was the largest in filling stage. (3) In the soil, the root activity was inverted “T ” type distribution. With the advancing of the fertility process, the root activity of different soil layers changed from small to large to small, and the highest active site of the root showed a downward trend. The height of 20-40 cm soil layer was the highest in jointing stage, the highest was 80-120 cm in large mouth stage and flowering stage, The filling stage and the wax ripening stage is the highest in 120 ~ 160cm. The average root length of 0 ~ 160cm was the highest in the big mouth period. (4) The total amount of root TTC reduction in the soil showed a “T” type distribution with low height and low height. According to the total amount of TTC reduction and total density, 0-20, 120-120 and 120-160 cm soil layers Respectively high-density area, medium-density area and low-density area. From the dynamic view, the total amount of TTC reduction and total density at the soil layers above 120 cm reached the maximum at flowering stage, and the maximum soil depth at 120-160 cm reached the filling stage. 0 ~ 160cm total root TTC reduction total volume and total density?