阿尔泰山布尔津林区不同草地类型物种多样性特征与生产力的关系

为探讨物种多样性与地上生物量的相关性以及物种多样性的垂直变化特征。以阿尔泰山布尔津林区5种草地类型为研究对象,通过对布尔津林区各草地类型的调查,分析了阿尔泰山布尔津林区各草地类型的物种多样性变化特征。结果表明:(1)5个草地群落类型地上生物量差异明显,荒漠草原和山地草甸草原较低,山地草原最高,而山地草甸和高寒草甸处于两者之间。(2)各草地类型群落间的物种多样性指数、优势度指数、丰富度指数和均匀度指数有明显差异,高寒草甸的物种优势度、多样性和均匀度的情况最好,山地草原的丰富度显著优于各草地类型的丰富度。(3)地上生物量只与山地草甸草原山地草甸中优势度和多样性有极显著相关关系,与荒漠草原物种多样性没有表现出显著相关。(4)在海拔900～2 400 m的范围内,草地群落的物种优势度、丰富度、均匀度和多样性指数变化基本一致,均表现为先上升后下降再上升的趋势,峰值出现在1 200～1 400,2 200～2 400 m的地带。研究结果对深入理解阿尔泰山布尔津林区草地资源的空间分布格局及可持续利用具有重要的意义。     

Effects of altitude and variety on nutrient levels and epiphytes of oats北大核心CSCD

Oat crops are a major animal feed source in the Qinghai-Tibetan plateau and nearby areas. Typically，the crops are used for making silage rather than hay because of frequent rain at harvest in autumn. However，there is little data on how the yield，forage quality and levels of epiphytes that may affect silage quality of different oat varieties are affected by altitude. Therefore，four oat varieties（Longyan No. 3，Longyan No. 5，Baiyan No. 2 and Bayou No. 3） were planted in 8 localities forming an altitude gradient： Huangzhong （2295 m），Tianzhu （2797 m），Shandan （2860 m），Hezuo （2957 m），Haiyan （3052 m），Maqu （3474 m），Maqin （3765 m）and Chengduo （4217 m）. Measurements included crop yield and dry matter （DM），water soluble carbohydrate （WSC），crude protein （CP），neutral detergent fiber （NDF）and acid detergent fiber （ADF）contents，and counts of lactic acid bacteria （LAB），molds，yeasts and aerobic bacteria. It was found that there were significant altitude and variety effects on fresh yield，nutritional quality and microbial epiphyte counts. With increase in altitude，fresh yield，WSC，NDF and LAB counts increased（P<0.05），as much as 284. 00%，15. 49%，10.81% and 11.60% increment were observed at Chengduo site than that at Huangzhong，respectively；meanwhile DM，CP and yeast and mold counts were reduced by 15. 67%，36.27%，23.53% and 7.75% at Chengduo compared with Huangzhong site，respectively. Among the four tested varieties，Longyan No. 5 had the highest fresh yield （75605 kg·ha−1），WSC （201.4 g·kg-1 DM） and NDF （604. 2 g·kg-1 DM） at the Chengduo site，followed by Longyan No. 3. The highest CP （119.7 g· kg-1 DM） and mold counts （4.12 lg cfu·g-1 FM） were observed in Baiyan No. 2 at the Huangzhong site. Bayou No. 3 produced the highest LAB and yeast counts at Maqin and Chengduo sites. In general，Longyan No. 3 and Longyan No. 5 gave better performance at sites above 3000 m altitude；for sites below 3000 m，the four tested varieties were all found to be suitable for silage production. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

海拔高度对‘香玲’核桃生长结果习性的影响

以引种的‘香玲’核桃为试材,对襄阳市保康县不同海拔区域的核桃生长结果习性进行调查研究,结果表明:在相同的生长年限下,引种的‘香玲’核桃平均树高、平均地径在海拔700~800 m呈现最大值,单株冠幅面积和单株结果数量在600~700 m呈现最大值,700~800 m产量最不稳定,病果率在海拔600~700 m最低;在海拔800 m以上,随着海拔的升高,树体平均高度、树体平均地径、单株冠幅面积和单株结果数量均呈现下降的趋势。因此,保康县600~800 m区域是最适宜‘香玲’核桃引种的区域。