高寒草甸退化草地—“黑土滩”植物量测定

依据高寒草甸草地秃斑地的多少和距居民点的远近划分为轻度退化草地(极少量秃斑地)、中度退化草地(少量秃斑地)、重度退化草地(大量秃斑地)和极度退化草地(全部秃斑地)四个退化草地等级。对各等级退化草地进行了植物量测定。结果表明:草地植物量(地上和地下)及土壤含水量,随着草地退化程度的加剧明显下降(P<0.01),毒杂草量则明显上升(P<0.01)。其中极度退化草地较轻度退化草地植被中嵩草属牧草优势度减少38,可食鲜草量减少219.2g/m~2,而毒杂草则增加99.6g/m~2,植物活根量(干物质)减少2390.6g/m~2,土壤含水量(0—10cm)减少10.02％,并对高寒草甸退化草地(黑土滩)的成因及治理途径提出了看法和意见。

DETERMINATION OF PHYTOMASS ON DETERIORATE GRASSLAND-"HEITUTAN"IN ALPINE MEADOW

According to the number of barren patch(BP) and distance from residential area,the 4 grades deteriorate grassland were divided. That was light(little of the BP),moderate(a little of the BP),heavy(all a large number of the BP)and exceeding deteriorate grass- land(all the BP).The phytomass on 4 grades deteriorate grassland were determined. The results show that the phytomass and soil moisture reduced significantly(P<0.01)by inceasing deteriorate grade to a high level, but poisonous weeds increased significantly(P<0.01). Comparing with light deteriorate grassland, the exceeding deteriorate grassland was sdudied: the dominance of Krosia(Kobresia L.),fresh herbages, underground ptytomass(dry matter) and soil moisture(0-10cm)decreased by 38,219.2g/m~2,2390.6g/m~2 and 10.02% respectively,but the poionous weeds increased by 99.6g/m~2. The cause of formation and managing measures on deteriorate grassland in Alpine Meadow(HEITUTAN)were discussed in this paper.