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固阳秦长城的历史文化内涵与精神价值
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作者 张文平 《鹿城学刊》 2023年第3期27-29,37,共4页
固阳秦长城始建于秦始皇三十三年(公元前214年),汉武帝时期作了加筑沿用,是秦汉长城的典型代表。固阳秦长城之内的北假中,在西汉时期开展了大规模的军事屯田;西汉晚期,匈奴呼韩邪单于内附五原塞,长城两侧见证了中原王朝与北方游牧民族... 固阳秦长城始建于秦始皇三十三年(公元前214年),汉武帝时期作了加筑沿用,是秦汉长城的典型代表。固阳秦长城之内的北假中,在西汉时期开展了大规模的军事屯田;西汉晚期,匈奴呼韩邪单于内附五原塞,长城两侧见证了中原王朝与北方游牧民族政权之间由对抗走向交流的融合历程。 展开更多
关键词 固阳秦长城 北假中 高阙 五原塞 昭君和亲 紫塞
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Technical efficiency and its determinants of the various cropping systems in the purple-soiled,hilly region of southwestern China 被引量:2
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作者 ZHANG Shi-chao WEI Chao-fu +1 位作者 SHAO Jing-an WU Zhao-juan 《Journal of Mountain Science》 SCIE CSCD 2016年第12期2205-2223,共19页
This study examines the technical efficiency(TE) differences among typical cropping systems of smallholder farmers in the purple-soiled hilly region of southwestern China.Household-,plot-,and crop-level data and commu... This study examines the technical efficiency(TE) differences among typical cropping systems of smallholder farmers in the purple-soiled hilly region of southwestern China.Household-,plot-,and crop-level data and community surveys were conducted to explore TE levels and determinants of typical cropping systems by using a translog stochastic frontier production function.Results indicate significant difference in TE and its determinants among cropping systems.The mean TEs of the rice cropping system(R),the rice-rape cropping system(RR),the rice-rape-potato cropping system(RRP),and the oil cropping system(O) are0.86,0.90,0.84,and 0.85,respectively,which are over 1.17 times higher than those of the maize-sweet potato-other crop cropping system(MSO) and the maize-sweet potato-wheat cropping system(MSW) at0.78 and 0.69,respectively.Moreover,Technical inefficiency(TIE) of different cropping systems is significantly affected by characteristics of the household as well as plot.However,the impact of land quality,mechanical cultivation conditions,crop structure,farming system,farm radius,household type,cultivated land area per capita,and annual household income per capitalon TIE vary by cropping system.Additionally,output elasticity of land,labor,and capital,as a group,is greater than the one of agricultural machinery and irrigation.Finally,when household-owned effective agricultural labor is at full farming capacity,optimal plot sizes for the R,RR,RRP,MSO,MSW,and 0 cropping systems are 1.12hm^2,0.35 hm^2,0.25 hm^2,2.82 hm^2,1.87 hm^2,and 1.17hm^2,respectively. 展开更多
关键词 Cropping systems Technical efficiency Land management Plot purple-soil Stochastic frontier Production Function
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