古浪县草原资源及其温性草原植被覆盖及生产力评价

将3S技术与地面调查相结合,通过决策树分类、像元二分模型和二元回归模型,分别对古浪县草原资源、温性草原植被覆盖及其生产力情况进行了研究。结果表明,古浪县总草原面积22.41万hm~2,其中高寒草甸、山地草甸、温性草原、温性荒漠和温性荒漠草原分别占1.68%、1.66%、32.55%、24.02%和40.08%;正常年景古浪县温性草原以20%FVC40%植被盖度为主,近10年温性草原FVC出现逐步改善的趋势;温性草原平均鲜草产量为1 042.70kg/hm~2,以500~1 000kg/hm~2产量草原所占面积较大,占温性草原总面积的50.01%,其次为1 000~500kg/hm~2草地,占41.87%,全县7.29万hm~2温性草原总鲜草产量7.61万t,可承载3.65万个羊单位。

Evaluation of vegetation coverage and productivity of temperate steppe in Gulang County

3S technology and ground survey were used to evaluate the natural grassland resource,the vegeta-tion coverage and productivity of temperate steppe in Gulang County through decision tree classification,dimidi-ate pixel model and binary regression model.The results showed that the total grassland area was 224 100 ha, the alpine meadow,mountain meadow,temperate steppe,temperate desert and temperate desert grassland ac-counted for 1.68%,1.66%,32.55%,24.02%,40.08% respectively.The vegetation coverage of temperate steppe(FVC)mainly ranged in 20% < FVC < 40% and the FVC increased in recent 10 years.The avaerage freash yeild of temperate steppe was 1042.70 kg/ha,the steppe area with yeild from 500nkg/ha to 1 000 kg/ha was the largest,which accounted for 50.01% of total steppe area,and followed by the steppe with yeild from 1 000 kg/ha to 1 500 kg/ha,which accounted for 41.87%.The total fresh yeild of 72 900 ha temperate steppe was 76100t and the carrying capacity was 36 500 sheep units.