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1.
数字农业的发展对于农业现代化转型升级具有重要意义。根据江西省县域数字农业相关数据和文献资料,分析江西省数字农业发展现状,指出目前江西省数字农业发展存在数据服务配套不完善、小农户应用困难以及法律法规政策建设相对落后等问题,提出应加强数字农业信息服务支持力度、培育新型农业经营主体,以及强化政策顶层设计等建议。 相似文献
2.
针对食用菌产业中出现的菌种选取不精,产量过剩,加工发展缓慢和环境污染以及技术创新力度不足等问题,政府相关部门应出台一系列的财税激励政策,重点推进食用菌产业全面的转型升级,切实提高食用菌产业的经济效益。通过分析食用菌产业发展的市场状况,总结食用菌产业转型升级的限制因素,为加快企业转型升级提出相应的财税激励政策建议,以推动食用菌产业的创新发展。 相似文献
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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
4.
Impact of grassland contract policy on soil organic carbon losses from alpine grassland on the Qinghai–Tibetan Plateau
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J. Cao Y. Gong E. T. Yeh N. M. Holden J. F. Adamowski R. C. Deo M. Liu J. Zhou J. Zhang W. Zhang S. Zhang D. Sheng S. Yang X. Xu M. Li Q. Feng 《Soil Use and Management》2017,33(4):663-671
Carbon storage in the soils on the Qinghai–Tibetan Plateau plays a very important role in the global carbon budget. In the 1990s, a policy of contracting collective grasslands to smaller units was implemented, resulting in a change from the traditional collective grassland management to two new management patterns: a multi‐household management pattern (MMP: grassland shared by several households without enclosures) and a single‐household management pattern (SMP: grassland enclosed and used by only one household). In 2016, 50 MMP and 54 SMP winter pastures on the Qinghai–Tibetan Plateau were sampled to assess the differences in soil organic carbon (SOC) between the two management patterns. Results showed that average SOC was significantly greater under MMP than under SMP, with an estimated 0.41 Mg C/ha/yr lost due to SMP following the new grassland contract. Based on the government's grassland policy, four grassland utilization scenarios were developed for both summer and winter pastures. We found that if the grassland were managed under SMP, likely C losses ranged between 0.31 × 107 and 6.15 × 107 Mg C/yr across the Qinghai–Tibetan Plateau relative to MMP, which more closely resembles pre‐1990s grassland management. Previous estimates of C losses have only considered land use change (with cover change) and ignored the impacts driven by land management pattern changes (without cover change). The new data suggest that C losses from the Qinghai–Tibetan Plateau are greater than previously estimated, and therefore that the grassland contract policy should be reviewed and SMP households should be encouraged to reunite into the MMP. These findings have potential implications for land management strategies not only on the Qinghai–Tibetan Plateau but also other grazing regions globally where such practices may exist. 相似文献
5.
Understanding the benefits provided by urban trees is important to justify investment and improve stewardship. Many studies have attempted to quantify the benefits of trees in monetary terms, though fewer have quantified the associated costs of planting and maintaining them. This systematic review examines the methods used to jointly analyse the costs and benefits of trees in the urban landscape, assesses the relative balance of benefits and costs, and attempts to understand the wide variation in economic values assigned in different studies. The benefits most frequently studied are those related to environmental regulation and property values, and the available data show that these usually outweigh the costs. Aesthetic, amenity, and shading benefits have also been shown to provide significant economic benefits, while benefits in terms of water regulation, carbon reduction and air quality are usually more modest. Variation in benefits and costs among studies is attributed largely to differences in the species composition and age structure of urban tree populations, though methodological differences also play a role. Comparison between studies is made difficult owing to differences in spatiotemporal scope, and in the way urban forest composition and demographic structure were reported. The overwhelming majority of studies concern deciduous trees in Northern America, and much less is known about urban forests in other regions, especially in the tropics. Future work should thus seek to fill these knowledge gaps, and standardise research protocols across cities. In light of ambitious goals in many cities to increase tree cover, ongoing advances in valuation methods need to provide a more comprehensive accounting of benefits and costs, and to better integrate economic assessment into the decision-making process. 相似文献
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玛沁县畜牧业现状及可持续发展对策 总被引:1,自引:0,他引:1
通过对玛沁县畜牧业发展现状的分析,总结多年来的经验,提出了畜牧业可持续发展的策略。 相似文献
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政府渔业补助政策与博弈 总被引:1,自引:0,他引:1
渔业补助政策是政府为弥补市场经济缺陷而采取的重要措施,本文应用博弈论对政府与渔民的互动博弈展开研究,并确立了混合策略模型下的政府和渔民各自最佳选择概率,达到纳什均衡,这对于解释当前政府渔业补助政策内涵与指导修订补助政策有参考意义。 相似文献
10.
新世纪我国林业建设进入了历史性变革时期,对森林效益的认识更加深化,对林业建设的需求更加全面、迫切,林业可持续发展对森林资源的培育、保护和管理有更新、更高的要求.根据我国林业建设战略性转变的要求,对森林培育的认识、目标以及策略、内容、科技等方面进行了分析,提出森林培育理论和技术如何适应建设战略性转变的建议. 相似文献