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基于因子分析的抗根肿病油菜品种(系)综合评价——以荆门市掇刀区根肿病发病区为例 被引量:2
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作者 侯晓静 龙永红 +2 位作者 龙飞 王瑾 许强 《中国油料作物学报》 CAS CSCD 北大核心 2022年第1期183-189,共7页
通过因子分析法,对16个油菜品种(系)的根肿病抗性和主要农艺性状进行了综合性评价。结果表明,1)通过因子分析,共提取2个特征值大于1的公因子,分别是经济指标因子和品质指标因子,二者累计方差贡献率86.637%,可代表原5个评价因子进行综合... 通过因子分析法,对16个油菜品种(系)的根肿病抗性和主要农艺性状进行了综合性评价。结果表明,1)通过因子分析,共提取2个特征值大于1的公因子,分别是经济指标因子和品质指标因子,二者累计方差贡献率86.637%,可代表原5个评价因子进行综合评价。2)综合得分排名与种植效益趋势较为吻合,表明评价结果可靠有效。油菜品系18ZP05、18苗337、18ZP01和SHR02在该根肿病发病区表现稳定且有较高的种植收益,可考虑在当地根肿病发病区域进行进一步的种植推广。 展开更多
关键词 因子分析 抗根肿病 油菜品种(系) 综合评价 种植效益分析
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Pattern Change and Regional Disparity Tendency of Cultivated Land Use in Jiangsu Province
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作者 金涛 徐舟 《Agricultural Science & Technology》 CAS 2013年第10期1517-1520,1525,共5页
The study has examined the tempo-spatial patterns of cultivated land use change in Jiangsu province. A principal component analysis (PCA) of 18 selected indicators of cultivated land use during the period 1970-2010 ... The study has examined the tempo-spatial patterns of cultivated land use change in Jiangsu province. A principal component analysis (PCA) of 18 selected indicators of cultivated land use during the period 1970-2010 identified 2 main pat- terns of change in planting productivity and economic efficiency. A major shift from production-centered pattern to profit-oriented one occurred in 1984, the time of grain yield surplus and the mitigation of population pressure. In response to the impending Opened Market System, there was a notable tendency of higher efficiency and less productivity since 1997, as well as remarkable regional disparity of cultivated land use change spatially. It revealed a relative decrease in grain cropping share, crop- ping scale and cultivation intensity in South Jiangsu, especially in Tai-Lake region, and the reverse in North Jiangsu. Some suggestions for the future were finally dis- cussed from the above findings. 展开更多
关键词 Cultivated land use Pattern change Regional disparity PCA Jiangsu Province
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Analysis on Comprehensive Benefits of a Company Planting Banana on Rented Lands
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作者 Shen Xilin Zhang Wentao Wang Xuehuas 《Ecological Economy》 2005年第4期92-97,共6页
A comprehensive evaluation is made in this article On the ec-benefit, social benefit, and economic benefit form banana planting of a company in three planting bases in Xinping County. Before the banana is planted, the... A comprehensive evaluation is made in this article On the ec-benefit, social benefit, and economic benefit form banana planting of a company in three planting bases in Xinping County. Before the banana is planted, the land is classified into Sloppy land, woodland and amble land We earefidly study the three types of land, analyze the various effects and benefits made by banana planting on these types of land, and make a eomprehensive, comment. 展开更多
关键词 bananaptanting comprehensive benefit EVALUATION
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Ecological compensation for winter wheat abandonment in groundwater over-exploited areas in the North China Plain 被引量:2
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作者 王学 李秀彬 +3 位作者 辛良杰 谈明洪 李升发 王仁靖 《Journal of Geographical Sciences》 SCIE CSCD 2016年第10期1463-1476,共14页
The land fallow policy was adopted by central and local governments to encourage the abandonment of water-intensive crops, such as winter wheat, in groundwater over-exploited areas. At the same time, since the 1990s, ... The land fallow policy was adopted by central and local governments to encourage the abandonment of water-intensive crops, such as winter wheat, in groundwater over-exploited areas. At the same time, since the 1990s, many households in the North China Plain (NCP) have chosen to replace the winter wheat and summer maize double-cropping system with the spring maize single-cropping system. Therefore, it is crucial to identify target land parcels for winter wheat abandonment and to design reasonable and proper standards for ecological compensation prior to the implementation of the land fallow policy in the NCP. In this study, multi-level Iogit models were used with household survey data in order to detect determinants across land parcel, household and village levels on household cropping system decisions; the opportunity costs for winter wheat abandonment were also calculated using cost-benefit analysis. The results show that: (1) land quality and irrigation condition at parcel level are two essential elements influencing household cropping system decisions. Nearly 70% of the total area of poor land and more than 90% of the total area of unirrigated land has suffered winter wheat abandonment. Target land parcels for the land fallow policy should be those that are irrigated and of high quality. (2) There were no significant differences between net profits from spring maize and summer maize under similar farming conditions, and the opportunity cost for winter wheat abandonment should be equal to the net profit of winter wheat. (3) The primary purpose of the land fallow policy is to induce groundwater recovery and restoration as a preliminary stage. A higher level of 350 yuan/mu is recommended as subsidy for ecological compensation at this stage. Later, the primary purpose of the policy should be a transition to a balance between exploitation and supplementation of water resources, and a lower level of 280 yuan/mu is recommended as a subsidy at this stage. 展开更多
关键词 land fallow ecological compensation multi-level Iogit model opportunity cost groundwaterover-exploited areas
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