坡向和建植年限对冷季型混播护坡草坪重要值和生物量退化的影响

Effects of slope orientation and planting years ondegradation rate of important value andbiomass of cold season mixed-sownslope protection turf

摘要:

以3个坡向(半阴坡EN 40°,阳坡WS 33°,阴坡WN 29°)上,由高羊茅、多年生黑麦草和草地早熟禾建成的混播护坡草坪为对象,建成1~5年连续测定3草种的重要值和相对生物量,研究坡向和建植年限对冷季型混播护坡草坪退化速率的影响。结果表明:1)坡向和建植年限对草坪草重要值和生物量退化速率总值有显著影响,建植年限是影响的主要因素,建植年限和坡向间的互作次之,坡向影响较小;2)3种草的重要值和生物量退化速率在建植年限间、坡向间有显著差异,坡向间重要值退化速率为多年生黑麦草＞总值＞高羊茅＞草地早熟禾,建植年限间重要值退化速率为总值＞多年生黑麦草＞草地早熟禾＞高羊茅,坡向间和建植年限间相对生物量退化速率均为草地早熟禾＞多年生黑麦草＞总值＞高羊茅;3)坡向和建植年限对3种草坪草退化表现有显著影响,第2年阳坡多年生黑麦草和草地早熟禾相对生物量退化速率为74.81%和86.13%,第4年阴坡高羊茅相对生物量退化速率为70.16%。综上,草地早熟禾和多年生黑麦草第2~3年退化最快,高羊茅在第4年退化最快,应依坡向制定相应的草坪建植和养护技术措施。

Abstract:

At three slope aspects(semi-shading slope EN 40°,sunny slope WS33°,shady slope WN 29 °)of hilly area with purple soil,mixed-sown slope-protection turf consisting of Festuca arundinacea,Lolium perenne and Poa pratensis were studied.The dynamics of relative frequency,relative coverage,relative density,important value and relative yield of the turfgrass within 1~5 years after sowing were analyzed,to study the effects of slope aspect and planting years on the degradation rate of the turf.Slope aspect and planting years had significant effects on the degradation rate of important value and total biomass of slope-protection turf,which was mostly affected by planting years,followed by the interaction of planting years and slope orientation,and least affected by slope orientation.The degradation rates of important value and biomass of the three grass species were significantly different among planting years and slope aspect.Effects of slope orientation on degradation rate of important value followed the order of L.perenne＞ total value＞F.arundinacea＞P.pratensis,and effects of planting years followed the order of total value＞L.perenne＞P.pratensis＞F.arundinacea,while effects of both slope orientation and planting years on degradation rate of relative biomass followed the order of P.pratensis＞L.perenne＞total value ＞F.arundinacea.Slope aspect and planting years had significant effects on the degenerative performance of the three grass species.The degradation rate of total biomass for L.perenne and P.pratensis was 74.81% and 86.13% in the 2nd year on sunny slope;while F.arundinacea had 70.16% degradation rate on shady slope in the 4th year.In conclusion,the slope aspect had different effects on the important value and biomass of three turf grass species,such as the fastest degradation rate for P.pratensis and L.perenne in 2~3 years,while in the 4th year for F.arundinacea.Therefore,the corresponding turf planting and maintenance technical measures should be formulated according to the slope orientation.