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1.
经济林良种是经济林产业的“芯片”,是经济林生产优质、高产、高效的物质基础。完善经济林良种推广政策,是实现经济林产业高质量发展的根本保障。通过数据收集和整理,系统梳理全国经济林良种推广现状,指出经济林良种推广中还存在着良种使用率不高,经济林低产低效;部分经济林良种存在超范围推广;良种审定过多,结构性过剩和种植品种过多,对接生产加工不畅等突出问题。进而提出从以种植为目标的良种推广转变为以生产加工等市场需求为导向的良种推广思路。从优化良种供给、加强良种推广的宏观指导、强化科技支撑和宣传培训、实施经济林提质增效工程和充分发挥产业协会、创新联盟的作用等方面给出优化经济林良种推广的政策建议。 相似文献
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新生代农民工的需求较上一代农民工有其特殊性。基于马斯洛需求理论,分析当前新生代农民工的生理需求未得到满足,对安全的需求增加,希望受尊重和社交的愿望强烈,并且有迫切的自我实现需求。然而,目前社会纯经济利益化的劳动关系难以满足新生代农民工的生理需求,劳动保障措施也无法完全满足新生代农民工的安全需求,劳资双方关系不对等不能满足新生代农民工尊重和社交的需求,劳动关系不稳定也影响了新生代农民工自我实现需求。新生代农民工同时存在的生理、安全、尊重、社交和自我实现这五种需求与现在经济利益化、不安全、不平等、不稳定的劳动关系形成了突出的矛盾。需要通过创建员工与企业共享式发展的劳动关系、建立和完善社会保障制度、建立平等的劳动关系以及建立稳定的劳动关系,满足新生代农民工不同层次的需求,建立稳定和谐的劳动关系。 相似文献
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Feeding activity and food size preferences were investigated in three groups of rainbow trout with initial weights ranging from 200 to 1000 g. Fish were given the option of releasing food from either of two demand feeding devices that contained either 6 mm or 9 mm food pellets. Individual biting activity (to activate release of food) was continuously monitored using specially designed passive integrated transponders (PIT-tags). In each of the groups, biting activity was strongly influenced by three individuals, which accounted for 70–85% of the total. Thus, high bite activity by few individuals indicates the development of social dominance hierarchies. There was no statistically significant correlation between number of bites and growth rate, indicating that the fish that operated the demand feeders did not gain any growth advantage. Trout that dominated the actuation of the feeders were found among both medium- and large-sized fish. There was no evidence of active food size selection, and the fish that most frequently operated the feeders defended one area of the tank rather than preferring the trigger that would have delivered food of the optimal size. 相似文献
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Marie-Laure Begout Anras 《Aquaculture International》1995,3(3):186-195
Feeding activity was investigated from June to October in a group of 60 sea bass, Dicentrachus labrax. The fish were kept in an earthen pond in a maritime wetland subject to the fluctuations of the natural environment. The fish fed by operating a demand feeder connected to a data logger which recorded each feeding act with a time reference. Meteorological and hydrological data were also recorded. Diurnal rhythms in feeding activity changed as the months progressed. Fish fed during daylight, preferentially at dawn in June, but in the middle of the day from August to October. Most feeding took place during subdued light. Feeding was closely and positively correlated to both daylength and water temperature; daylength being the most related factor associated with rainfall and East-West wind direction. 相似文献
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耕地需求预测方法研究——以广西资源县为例 总被引:1,自引:1,他引:1
结合广西省资源县土地利用总体规划的实践,采用粮食需求法、部门预测法和灰色预测法等几种方法进行耕地需求预测的方法研究。预测的结果不仅保证了耕地总量的动态平衡,同时保证了重点建设项目用地的需要,该研究可为土地利用总体规划的编制工作提供科学依据。 相似文献
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本文首先从玉米生产、消费、期终库存及国际贸易等四个方面对世界玉米供求状况做了全面分析,然后利用往年数据建立回归方程,并对未来五年的玉米生产、消费、库存和出口量做趋势分析,并在此基础上,简单分析了世界和中国粮食安全所面临的形势。 相似文献
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农业技术创新和进步是中国未来农业生产增长的原动力。农业技术创新受技术市场需求、资源配置偏向、农业科研水准和农业比较利益等因素的影响。其中,制度因素对技术创新的作用日益增强。 相似文献
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The shift towards community participation in the eradication of trypanosomosis calls for investigation the underlying incentive
structure for individuals in the community to cooperate in the provision of various control methods. Survey data were used
to assess patterns of the community’s demand for insecticide pour-ons and trypanocidal drugs and factors affecting individual}
demand in The Gambia. The results show that insecticide pour-on is strongly preferred. Similarly, farmers revealed a preference
for community-based provision scheme. Factors affecting an individual farmer’s decision to invest in either pour-on or trypanocidal
drugs were highlighted. While there are many factors associated with farmer’s decisions to invest in trypanosomosis control
methods and to participate in collective actions, the results indicate that farmers} are ready to anticipate complete privatization
of veterinary services through community-based schemes. 相似文献
10.
通过对巢湖市两个农业大县农民的调查,建立二元回归模型,针对性别、年龄、受教育程度、家庭收入、对现代农业技术的认知度、培训与需求的一致性等因素分析影响农民参加现代农业技术培训的意愿程度。实证结果证实,年龄、性别、受教育程度、对现代农业技术的认知度是影响农民参加现代农业技术培训意愿的主要因素。 相似文献