黄河源区退化草地褐鳞苔草种植技术及对土壤改良效果研究

Study on cultivating technology and soil improvement effect of Carex brunnescen on degraded grassland in the source area of the Yellow River

【目的】探索高寒退化草地褐鳞苔草种植及改良土壤的技术方法。【方法】采用随机区组试验设计,野外温室条件下开展ABT6号生根粉、播种深度和育苗基质处理对褐鳞苔草种子出苗及苗木生长的影响;然后将苗木种植至铺设有草方格的沙丘上,观测其生长适应性及对土壤肥力的提升效果。【结果】用20 mg/kg的ABT6号浸种12 h,盆栽穴播深度0.5~1.0 cm时种子出苗和成苗效果最好;以50%草炭土+25%珍珠岩+25%蛭石混合,50%亚高山草甸土+30%高寒风沙土+20%腐熟羊粪混合,45%草炭土+54%高寒风沙土+1%复合肥混合3种基质育苗成苗率均达95%以上,且差异不显著。与未做任何措施的沙丘和未做任何措施的沙丘移栽褐鳞苔草相比较,铺设草方格的沙丘种植褐鳞苔草2年后其植被覆盖度分别增加了34.9%和18.1%,种群密度增加了423.9%和55.1%,地下茎总长度增加了648.6%和170.7%,总生物量鲜质量增加了319.8%和117.6%;且根区0~15 cm土壤有机质提高了177.6%和49.8%,速效钾提高了202.6%和56.6%,速效氮提高了138.6%和48.0%,速效磷提高了170.8%和29.5%。【结论】褐鳞苔草种子繁育苗种植在铺设有草方格的沙丘后其生长适应性良好,可显著提高土壤肥力,该技术在高寒退化草地上具有较好的推广应用潜力。

【Objective】The study was conducted to explore the practical techniques of cultivation and soil improvement of Carex brunnescen in Alpine degraded grassland.【Method】The effects of rooting powder(ABT No.6),sowing depth and seedling substrates treatments on seed emergence and seedling growth of C.brunnescen were determined in field greenhouse;and then the seedlings were transplanted on the sand dune treated with straw checkboard barriers(SCB),followed by observing their growth adaptability and improvement effect on soil fertility.【Result】The seedling growth effect was the best when soaked the seeds in ABT No.6 with a concentration of 20 mg/kg for 12 h and the depth of potted acupoints is 0.5~1.0 cm.The growth effect showed no significant different in the three seedling substrate treatments,which were the 50%peat soil+25%perlite+25%vermiculite mixture 50%subalpine meadow soil+30%aeolian sandy soil+20%rotten sheep manure mixture,and 45%peat soil+54%aeolian sandy soil+1%compound fertilizer mixture.Compared with the sand dunes treated with no measures and plants transplanted in sand dunes treated with no measures,plants transplanted in sand dunes treated with SCB increased the vegetation coverage by 34.9%and 18.1%,population density increased by 423.9%and 55.1%,the total length of underground stems increased by 648.6%and 170.7%,and the fresh weight of total biomass increased by 319.8%and 117.6%,respectively;and the organic matter in the root zone soil(depth 0~15 cm)increased by 177.6%and 49.8%,the available potassium increased by 202.6%and 56.6%,the available nitrogen increased by 138.6%and 48.0%,and the available phosphorus increased by 170.8%and 29.5%,respectively.【Conclusion】The seedlings of C.brunnescen transplanted in the sand dunes treated with SCB showed good growth adaptability and could improve soil fertility,which indicated broad prospects for its application and extension in alpine degraded grassland.