摘要
在黄土高原丘陵沟壑区以 4龄苜蓿 (Medicago sativa)、沙打旺 (Astragalus adsurgens)和甘草 (Giycyrrhiza uralensis)单播人工草地为材料 ,人工牧草、杂草和土壤 3方面研究了其生产性能和生态特性。在相同的管理条件下 ,沙打旺种群高度平均高于苜蓿 33.8% ,是甘草的 6 .2倍 ;苜蓿的密度分别是甘草和沙打旺的 5 .9倍和 2 .6倍 ;沙打旺盖度最大 ,苜蓿次之 ,甘草最小。三种牧草的地上生物量及其占群落生物量的比例依次是苜蓿 >沙打旺 >甘草 ;苜蓿种群生物量占群落的比例接近沙打旺 ,二者远高于甘草。甘草人工草地的杂草种数、杂草生物量及其生物量占群落的比例均最大。0～ 10 0 cm土层内三种人工草地的地下生物量依次为甘草 >苜蓿 >沙打旺。 0～ 10 0 cm土层内营养物质含量 :全 P,苜蓿 >甘草 >沙打旺 ;全 N,苜蓿与甘草接近 ,高于沙打旺 ;速效 P、速效 N都是甘草最高 ;有机质含量 ,苜蓿接近甘草、高于沙打旺。讨论了管理措施与人工草地的关系 。
Lucerne (Medicago sativa), milkvetch (Astragalus adsurgens) and licorice (Glycyrrhiza uralensis) are among the most important forage legumes on the Loess Plateau in China. Various studies have been undertaken on herbage dry matter yield, effects on water and soil conservation, and management aspects of these three legume species. However, study on soil fertility, weeds, and botanical composition of the plant communities has been sparse. Therefore, the biomass, weed invasion and soil fertility of four-year-old monocultures of lucerrne, milkvetch and licorice were investigated on the rolling country of the Loess Plateau in Huanxian county, Gansu Province, China in 2002. The results showed that the population height of milkvetch is 33.8% and 623.0% higher than lucerne and licorice, respectively. Similarly, milkvetch had the highest coverage (65.8%), followed by lucerne (48.5%), and licorice had the lowest coverage (1.0%). The plant density measured as number of plants per m^2 was 22.5 for lucerne, 8.5 for milkvetch and 3.8 for licorice. The above-ground biomass of lucerne, milkvetch and licorice was 255.2, 152.6 and 1.1g/m^2, respectively, while total community above-ground biomass of lucerne, milkvetch and licorice meadows was 271.1, 169.6 and 115.5g/m^2, and the above-ground biomass ratios of each legume species. To their total communities were 91.9%, 90.0% and 0.9%, respectively. The under-ground biomass of licorice, lucerne and milkvetch meadow communities at 0～100 cm soil depth was 1 142.4, 307.8, and 195.1g/m^2, respectively, and the percentage of licorice, lucerne and milkvetch was 72%, 89% and 67%, respectively. The total community above-ground to underground biomass ratio of licorice, lucerne and milkvetch meadows was 9.89, 1.14 and 1.15. The main weed species found in the three fields differed. The most important weeds in the lucerne field were Lespedeza davurica, Artemisia capillaries and Pennisetlum flaccidum, and the three weeds above-ground biomass percentages were 21.1%, 11.2% and 11.1%, respectively; whereas these percentages in licorice meadow were 16.9%、26.8%、33.2%, respectively. There were much fewer weeds in milknetch fieds in terms of both species and density. The major weed found in milkvetch meadow was Agriophyllum arenarium, and its percentage of above-ground biomass was 6.7%. The soil water content of licorice, lucerne and milkvetch meadows at 0~200 cm soil depth was 175.8, 210.1 and 142.8mm, respectively. The content of total phosphorus, nitrogen and organic matter in the soil of those three fields followed the same order, i.e., lucerne>licorice>milkvetch, but the highest contents of available P and N in the soil were found in the licorice field. Based on this study's production, weed biomass percentage and soil fertility measurements, lucerne is the most suitable planting on the Loess Plateau. Moreover, the community characteristics of licorice meadow are similar to natural rangeland, thus, for restoration and improvement of natural rangeland in this area. Planting licorice is economical and easy. The effects of management practice on field productivity is discussed, and it is suggested that increasing input, especially fertilizer input, will be necessary to maintain productive and stable forage legume communities.
出处
《生态学报》
CAS
CSCD
北大核心
2004年第5期932-937,共6页
Acta Ecologica Sinica
基金
国家重点基金研究发展规划资助项目 ( G2 0 0 0 0 1860 2 )
国家自然科学基金西部重大研究计划资助项目 ( 90 10 2 0 11)
环县农牧交错带生态农业建设与示范项目~~
