黄土高原半干旱区退化灌草植被的恢复与重建

RECOVERY AND RECONSTRUCTION OF DEGRADED SHRUB-GRASS VEGETATION IN SEMI-ARID REGION OF LOESS PLATEAU

针对黄土高原半干旱区灌草植被退化严重的关键问题 ,进行了长期的定位研究 ,提出了灌草植被封育、改良、立体配置等快速恢复与重建的技术体系。试验结果表明 :主要草地群落本氏针茅、百里香适宜封育期为 3～ 5a ,产草量可提高 5 1～ 7 5倍。大针茅适宜封育期为 5a ,产草量可提高 1 5～ 5 0倍 ;改良草地最佳组合荒山穴播为本氏针茅 +杂类草、达乌里胡枝子 +本氏针茅群落 ,产草量提高 6 1～ 6 4倍。撂荒地开沟种植为本氏针茅 +冷蒿、本氏针茅 +红豆草、本氏针茅 +达乌里胡枝子群落 ,产草量提高 4 6～ 4 8倍。荒山隔带耕翻种植为芨芨草、本氏针茅 +紫花苜蓿、本氏针茅 +老芒麦、达乌里胡枝子 +本氏针茅群落 ,产草量提高4 5～ 6 5倍 ;灌草立体配置结合工程整地措施 ,建立了以柠条 +芨芨草、沙棘 +草木樨和山桃 +芨芨草为主的集流灌草配置模式 ,现已形成可更新的稳定的灌草群落类型。该体系的组装配套与试验、示范、推广为黄土高原农牧交错区灌草植被的快速恢复提供了重要的科学依据。

After Long years sited experiment,recovery and reconstruction system of close,improvement and solid collocation are put forward against the worsen degradation.The experiment show that after 3～5 years of close,the main community biomass of S.bungeana and T.mongolicus increased 5.1～7.5 times than that of the unclosed,after reasonable close duration of S.grandis,i.e.,5 years,the biomass increased by 1.5～5.0 times.The fitted combinations of improved grassland in barren hill by bunch planting are S.bungeana+forb,L.davurica+S.bungeana,biomass increased 6.1～6.4 times than than of the unimproved.Ditch planting in wasteland of S.bungeana+A.frigida, S.bungeana+O.viciaefolia,S.bungeana+L.davurica,its biomass increased 4.6～4.8 times than that of the implanted.Ploughed planting of every two strip in barren hills are A.splendens,S.bungeana+M.sativa,S.bungeana+E.sibiricus+L.davurica,the biomass increased 4.5～6.5times than that of the implanted.Shrub-grass solid collocation,which are Caragana korshinskii+A.splendens+H.hamnoicle+M.suaveolens and P.davidiana+A.splendens,have formed stable renewable communities.The experiment,demonstration and popularization provide the quick recovery of shrub-grass in semi-arid region of Loess Plateau with scientific foundation.