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新型高密度灌木幼苗移栽机仿真与试验 被引量:2
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作者 赵美卿 卫立新 郭凌云 《农业工程》 2022年第10期107-113,共7页
针对裸根灌木幼苗具有根系软、乱和股头多等特点,以及已有的链夹式移栽机不能满足小行距高密度移栽要求,提出了一种可用于株距<200 mm、行距<160 mm,10行同时移栽的新型灌木幼苗移栽机械。对高密度灌木幼苗的移栽工艺研究后,设计... 针对裸根灌木幼苗具有根系软、乱和股头多等特点,以及已有的链夹式移栽机不能满足小行距高密度移栽要求,提出了一种可用于株距<200 mm、行距<160 mm,10行同时移栽的新型灌木幼苗移栽机械。对高密度灌木幼苗的移栽工艺研究后,设计了移栽机栽植机构、放苗机构、起垄机构、旋耕机构及悬挂系统,并进行传动系统仿真,结果表明,移栽机的传动系统达到移栽过程中设计要求。设计了一种新型开沟器,根据开沟器的实际受力特点,运用离散元技术和有限元分析技术对其进行仿真试验,结果表明,开沟器强度满足要求。对新型移栽机的物理样机进行现场移栽试验,结果表明,该移栽机能高效解决根系软、乱和股头多的裸根灌木幼苗移栽问题,并且平行排布、除草方便,适合小行距高密度移栽。幼苗植入深度(移栽深度)7~12 cm,直立度80°~90°,移栽苗成活率90%以上。 展开更多
关键词 密度灌木幼苗 移栽机 小行距 开沟器 发动机特性
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白冠长尾雉冬季夜栖行为与夜栖地利用影响因子的研究 被引量:29
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作者 孙全辉 张正旺 +1 位作者 朱家贵 高振建 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第1期108-112,共5页
1999年12月至2000年3月,通过野外观察、无线电遥测以及样方调查对河南董寨鸟类自然保护区白冠长尾雉的夜栖行为和冬季夜栖地进行了研究.结果表明,在研究地区针阔混交林和人工针叶林是其冬季夜栖的2种主要植被类型.由于冬季落叶乔木的... 1999年12月至2000年3月,通过野外观察、无线电遥测以及样方调查对河南董寨鸟类自然保护区白冠长尾雉的夜栖行为和冬季夜栖地进行了研究.结果表明,在研究地区针阔混交林和人工针叶林是其冬季夜栖的2种主要植被类型.由于冬季落叶乔木的盖度显著降低,所以白冠长尾雉的夜栖地的使用受到限制,夜栖树种类也主要限于常绿针叶树种.调查显示,冬季白冠长尾雉的夜栖地一般靠近水源、远离林缘,位于山体中上部坡度较大的地方,夜栖树通常高大并且盖度良好.对夜栖地变量进一步分析表明,冬季影响白冠长尾雉夜栖地利用的主要因素依次为:海拔、栖位下方盖度、灌木密度、坡度、栖枝高度、夜栖区乔木的密度和胸径、栖位上方盖度、坡向以及距水源的距离等.白冠长尾雉的夜栖行为受到多种因素的影响,比较重要的有季节、天气和性别因素.为保护白冠长尾雉的夜栖地,保护区应重视人工针叶林的保护. 展开更多
关键词 白冠长尾雉 夜栖行为 夜栖地利用 无线电遥测 影响因子 植被类型 灌木密度
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Carbon Sequestration Effects of Shrublands in Three-North Shelterbelt Forest Region, China 被引量:11
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作者 LIU Wenhui ZHU Jiaojun +4 位作者 JIA Quanquan ZHENG Xiao LI Junsheng LOU Xuedong HU Lile 《Chinese Geographical Science》 SCIE CSCD 2014年第4期444-453,共10页
Three-North Shelterbelt Forest (TSF) program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region ... Three-North Shelterbelt Forest (TSF) program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that: 1) The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 10^7 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2) In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo vat. heterophylla. The carbon sequestration of/-/, rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3) The total carbon sequestration of shrubland in the study region was 4.5 x 107 Mg C with a mean annual carbon sequestration of 1.5× 10^6 Mg C. The carbon density in the four sub-regions decreased in the following order: the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a baseline reference for future research in this area. 展开更多
关键词 BIOMASS biomass density carbon density carbon sequestration carbon sequestration rate carbon storage Three-NorthShelterbelt Forest (TSF)
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