平茬时期与留茬高度对宁夏荒漠草原柠条营养成分和再生的影响
Effects of Stubble Period and Stubble Height on Nutrient Mass Fraction and Regeneration of Caragana korshinskii in Desert Steppe of Ningxia

以宁夏荒漠草原的人工柠条林带为对象，研究不同月份平茬和留茬高度为0、5、10和15 cm对柠条营养成分及再生性能的影响。结果表明，各个生育期内，柠条蛋白质、粗脂肪、酸性洗涤纤维、中性洗涤纤维和粗灰分质量分数呈现波动变化，其中粗蛋白质量分数变幅为11.19%~15.38%， 6月最高。留茬高度对柠条当年再生速度、分枝数、地上生物量显著影响；留茬0 cm植株地径的日增量和冠幅最高，留茬15 cm最低；返青率随着留茬高度的增加而降低。5、6月平茬柠条的再生速度、冠幅增量、地径增量和萌枝长增量显著好于其他月份平茬，返青率以5-7月平茬柠条较高。研究认为，从饲用营养成分和柠条再生考虑，宁夏荒漠草原柠条最佳平茬时期为6月，高度为齐地平茬。
Taking artificial forest belt of Caragana korshinskii distributed in desert steppe of Ningxia as objective,we studied the effect of different stumping months and stubble heights (0 cm,5 cm,10 cm and 15 cm) on nutrient component and regenerative properties of Caragana korshinskii. The results showed that crude protein,crude fat,acid detergent fiber,neutral detergent fiber and crude ash content(mass fraction) of Caragana korshinskii changed in fluctuation in each growth period. The crude protein content was between 11.19% and 15.38%,reaching the highest in June. Different stubble heights had few marked influence on Caragana korshinskii’s regeneration rate,number of branches and the aboveground biomass in the current year; daily increment of grand diameter and the crown were the highest when the stubble was 0 cm,15 cm was the lowest; reviving rate increased with the increase of stubble height . In May and June,the increment of reproduction speed,crown incremental,sprouting length and daily increment of the grand diameter of the stubble of Caragana korshinskii was significantly better than that of rest of the year,from May to July the stubble of Caragana korshinskii had higher reviving rate. The Studies showed that the best stumping period of Caragana korshinskii in desert steppe of Ningxia was June and the stubble height ought to close to the ground under the consideration of feeding nutrition and regeneration of Caragana korshinskii.