摘要
在自然降雨条件下,选择15°坡地种植禾本科牧草新麦草、草地雀麦、无芒雀麦、垂穗披碱草、苇状羊茅和蓝茎冰草,建立径流试验小区,比较不同禾草生物学特性变化及其坡地水土流失防治效果,结果表明:6种禾草越年后4月份返青,6月份植株密度最高,单株叶片数显著增加,7月份草地雀麦与无芒雀麦草层高度显著高于其它禾草,达到38.5 cm和33.7 cm,且不同禾草的地表覆盖度与生物量快速增加,8月份趋于稳定,草地雀麦与无芒雀麦地表覆盖度达到81.9%和91.9%,无芒雀麦地上生物量最高为3614.2 kg/hm^2,苇状羊茅地下生物量最大为9304.9 kg/hm^2。与此同时,6种禾草的坡地水土流失防治效果显著,且随降雨量与降雨强度增加,水土保持作用更加明显,其中,草地雀麦和无芒雀麦与其它禾草相比,保水固土能力最强,2006年地表径流量为69717.5 t/km^2和71253.2 t/km^2,保水能力达到59.9%和59.0%,土壤侵蚀模数为7831.9 t/km^2.a和7488.9 t/km^2.a,固土能力达到69.7%和71.0%,其次是蓝茎冰草、新麦草和垂穗披碱草地,苇状羊茅保水固土能力相对最弱,仅为9.1%和20.7%。
The experiment was conducted to study soil and water conservation of six grasses, including Psathyrostachys juncea , Bromus riparius , Bromus inermis , Elymus nutans , Festuca arundinacea and Agropyron smithii, by analyzing changes of grass biological characteristics and amount of water and soil loss in runoff plots on 15° slope land under natural rainfall. Results were the following： Six grasses returned green in April. Then grass densities were the most in June, and their leaves increased obviously. Grass heights of Bromus riparlus and Brornus inermis were more than others significantly with 38.5em and 33.7 cm in July, and grass covers and biomasses improved rapidly, and then kept stable level in August. Covers of Bromus riparius and Bromus inermis were 81. 9% and 91.9% this time, and overground biomass of Bromus inermis and underground biomass of Festuca arundinacea were the most with 3614.2 kg/hm^2 and 9 304. 9 kg/hm^2. At the same time, effects of six grasses planting on soil and water conservation on slope land were significant, and clearer with rainfall and rainfall intensity increasing. Meanwhile, Capabilities of Bromus riparius and Bromus inermis on soil and water conservation were the most in six grasses. Their capabilities of water conservation were 59.9% and 59.0% with amount of surface runoff of 6 9717.5 t/km^2 and 71 253.2 t/km^2 in 2006, and their capabilities of soll conservation were 69.7 % and 71.0 % with soil erosion modulus of 7 831.9t/km^2. a and 71 253.2t/km^2. a. Then those of Agropyron smithii, Psathyrostachys juncea, and Elymus nutans were the next, and Festuca arundinacea capabilities of soil and water conservation were the least only with 20.7% and 9.1%.
出处
《水土保持学报》
CSCD
北大核心
2008年第3期158-162,共5页
Journal of Soil and Water Conservation
基金
北京市科技新星计划(B类)项目(2005B02)
北京市优秀人才培养资助D类项目“牧草刈割对坡地土壤氮素流失的影响”
北京市农林科学院青年科研基金课题“农村裸露地生态草植被快速修复技术研究与示范”
关键词
禾草
生物学特性
水土保持
grasses
biological characteristics
soil and water conservation
