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西藏“一江两河”耕地生态安全时空格局与障碍诊断 被引量:21
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作者 李丹 田沛佩 +2 位作者 罗红英 罗玉峰 崔远来 《农业机械学报》 EI CAS CSCD 北大核心 2020年第10期213-222,共10页
基于青藏高原农业活动对耕地生态系统的影响,针对青藏高原耕地生态安全面临的问题,从压力状态响应(Pressstateresponse,PSR)概念模型出发,提出由3类要素、13种指标所组成的耕地生态安全评价指标体系,构建西藏“一江两河”地区耕地生态... 基于青藏高原农业活动对耕地生态系统的影响,针对青藏高原耕地生态安全面临的问题,从压力状态响应(Pressstateresponse,PSR)概念模型出发,提出由3类要素、13种指标所组成的耕地生态安全评价指标体系,构建西藏“一江两河”地区耕地生态安全评价模型,分析1985—2013年期间耕地生态安全的时空演变格局,探讨不同区域耕地生态安全的障碍因素。结果表明,西藏“一江两河”地区农业活动强度较大,尤其2000年以来,化肥、农药的成倍施用给生态安全带来巨大的隐患。20世纪,各县耕地生态安全基本处于“优秀”水平;2000—2010年,各县耕地生态安全等级下降,逐步向“差”转化;2010年以后,耕地生态安全有所改善,逐渐恢复为“优秀”或“良好”。整体来看,“一江两河”地区耕地生态安全水平较为一致,仅个别县域生态安全水平较为落后。区域耕地生态安全障碍因子具有相似性和差异性双重特征,单位面积氮肥、磷肥施用量是限制耕地生态安全的主要障碍因素。本研究揭示了高原地区耕地生态安全的演变过程,可为制定差别化的生态安全调控策略提供依据。 展开更多
关键词 耕地生态安全 时空格局 障碍因子 农业活动 “一江两河”地区
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关于西藏饲草种植模式探讨——以拉萨市为例 被引量:5
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作者 周娟娟 魏巍 《西藏农业科技》 2019年第1期10-13,共4页
以拉萨市3县传统农区、农牧交错区和牧区的气候特征、适种品种为基础,查阅西藏农业科研资料进行归纳总结,提出河谷农区开展冬青稞、冬小麦收获后种植燕麦、箭筈豌豆、黑麦草等牧草的复种模式,并将豆科牧草箭筈豌豆、苜蓿纳入轮作模式中... 以拉萨市3县传统农区、农牧交错区和牧区的气候特征、适种品种为基础,查阅西藏农业科研资料进行归纳总结,提出河谷农区开展冬青稞、冬小麦收获后种植燕麦、箭筈豌豆、黑麦草等牧草的复种模式,并将豆科牧草箭筈豌豆、苜蓿纳入轮作模式中,建立粮、经、饲三元种植结构;农牧交错区充分发挥农牧交错优势,进行科学的配送模式探索,海拔4000m以下挖掘高产优质饲草资源,并大力推广较为成熟的品种饲用玉米、燕麦等,开展以饲用玉米和燕麦为主栽品种的轮作制度;牧区推广燕麦+箭筈豌豆、小黑麦+箭筈豌豆等窝圈种草混作技术模式。 展开更多
关键词 西藏 一江两河 饲草 复种 轮作 种植模式
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Population Characteristics and Future Population Countermeasures for the Studied Counties in Tibet, China 被引量:1
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作者 LIUJian PENGChuan-zhong +1 位作者 Xiang-mei ZHONGXiang-hao 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第4期739-744,共6页
Focusing on the 18 counties along “One River and Two Tributaries” region, and based on the data from China 3nl, 4th and 5th population censuses, this article has analyzed the time and spatial changing patterns of th... Focusing on the 18 counties along “One River and Two Tributaries” region, and based on the data from China 3nl, 4th and 5th population censuses, this article has analyzed the time and spatial changing patterns of the population in this region. The analyses show that since the 3nl population census, total population, average age and total birth rate have all changed considerably: ① Total population has grown, fast, with most counties' annual average growth rate of more than 10. ② In terms of the region's average age, in 2000 the age in the 18 counties is younger than 30 years old. ③ Compared with the 3nl population census, labor force by the 5th census is much younger. ④ Countermeasures are proposed to control population by controlling birth rate as the result of the local resident's quality improvement by education. 展开更多
关键词 Key words average age total birth rate dependency index population development countermeasures one river and two tributaries region TIBET
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An Analysis of Labor Resources “One River and Two Tributaries” Region in Tibet, China
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作者 PENGChuan-zhong LIXiang-mei +1 位作者 LIUJian ZHONGXiang-hao 《Wuhan University Journal of Natural Sciences》 CAS 2005年第4期751-758,共8页
Focusing on the region of Yarlung Zangbo River and the middle reaches of itstwo tributaries of Nianchu River and Lhasa River in Tibet (Hereafter referred to as the 'One Riverand Two Tributaries' region), and b... Focusing on the region of Yarlung Zangbo River and the middle reaches of itstwo tributaries of Nianchu River and Lhasa River in Tibet (Hereafter referred to as the 'One Riverand Two Tributaries' region), and based on the data from China 3rd, 4th and5th population censuses,the article has analyzed change patterns of this region' s labor force. Major findings from thestudy are summarized as follows; (1) Compared with the data from the 3rd census, labor forcepopulation in 2000 has increased significantly. (2) Children dependency coefficient has dropped,while old people dependency coefficient has changed very slightly with an increase of 0. 047% only.(3) Compared 2000 with 1982, illiteracy and semi-illiteracy rate of the population above 15 yearsold have decreased significantly by 30. 69 percentage points, but still higher than the nationalaverage. (4) Women' s illiteracy rate has dropped faster than men's, but up to 2000 it was generallyquite high. The upgrading of the entire population's overall quality has a long way to go. 展开更多
关键词 labor force resources children dependency coefficient old people dependencycoefficient labor force' s education level one river and two tributaries region
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基于随机前沿生产函数法的饲草生产技术效率测算及影响因素分析——以西藏“一江两河”地区为例 被引量:6
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作者 曲云鹤 余成群 +2 位作者 孙维 武俊喜 李少伟 《草业学报》 CSCD 北大核心 2015年第10期70-79,共10页
以西藏"一江两河"地区农户调研数据为基础,运用随机前沿生产函数估算农户饲草生产技术效率及影响因素,并从饲草类别、农业规模和地区分布3个维度进一步分析技术效率的增产空间。结果显示,饲草生产存在显著效率损失,提高生产效... 以西藏"一江两河"地区农户调研数据为基础,运用随机前沿生产函数估算农户饲草生产技术效率及影响因素,并从饲草类别、农业规模和地区分布3个维度进一步分析技术效率的增产空间。结果显示,饲草生产存在显著效率损失,提高生产效率,单产还有近30%的增长空间;投入要素劳动、种子、燃料、农家肥、化肥和土地产出弹性分别为0.1423,0.2197,0.1309,0.2600,0.2265和0.0206;品种差异是饲草技术效率最主要影响因素,农业规模和流动资金要素对饲草生产效率提高产生间接负向影响,人力资本和农业综合生产能力要素对饲草生产效率影响不显著。释放饲草生产技术效率增产空间,可采取推广普及豆科饲草生产技术、扩大饲草种植规模、各地区(特别是拉萨地区)进一步明确适宜引种的饲草品种等策略。 展开更多
关键词 随机前沿生产函数 饲草生产技术效率 西藏“一江两河”地区
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