共查询到20条相似文献,搜索用时 15 毫秒
1.
M. Z. Xia 《Journal of Agronomy and Crop Science》1993,171(3):145-152
In a field experiment in the winter seasons of 1985/86 and 1988/89 at Xichang, China, the effects of defoliation on seed yield of Vicia faba and its photosynthetic compensation were investigated by removing all leaves, some leaves from different plant positions at the beginning of flowering and the beginning of pod formation. Seed yield decreased by 37.3–52.3 % in plants with upper leaves removed at the beginning of flowering. Removal of middle leaves at the beginning of pod formation had the most significant effect, followed by the of upper and lower leaves removed, causing yield decreases of 43.4–64.3 %, 18.6–24.7 % and 8.9–12.3 %, respectively. Removal of leaves at the beginning of pod formation resulted in a greater reduction in seed yield, total dry weight, harvest index, and number of pods and seeds per plant than leaf removal at the beginning of flowering.
The photosynthetic rate and export rate of photosynthate of upper leaves at the beginning of flowering, and middle leaves at the beginning of pod formation were the greatest during both years of the experiment. Photosynthetic rate increased and reached its maximum at 4–5 days after leaf removal, then decreased, but, yet greater than the control leaves at 9–11 days after leaf removal. In the meantime, transport of photosynthetic products was accelerated. In general, removal of leaves from the upper and middle third of the plant increased the export rate of photosynthate by ca. 20 %. Photosynthetic compensation could not fully make up the loss caused by leaf removal, so grain yield was decreased by all treatments. The full defoliation decreased yield by > 70 %. 相似文献
The photosynthetic rate and export rate of photosynthate of upper leaves at the beginning of flowering, and middle leaves at the beginning of pod formation were the greatest during both years of the experiment. Photosynthetic rate increased and reached its maximum at 4–5 days after leaf removal, then decreased, but, yet greater than the control leaves at 9–11 days after leaf removal. In the meantime, transport of photosynthetic products was accelerated. In general, removal of leaves from the upper and middle third of the plant increased the export rate of photosynthate by ca. 20 %. Photosynthetic compensation could not fully make up the loss caused by leaf removal, so grain yield was decreased by all treatments. The full defoliation decreased yield by > 70 %. 相似文献
2.
失地农民补偿中情感资本补偿的缺失 总被引:1,自引:0,他引:1
人类的发展阶段由低级向高级阶段进行着,人们不再仅仅追求物质享受,开始了精神境界的追求。而在当前的征地过程中,对农民的失地补偿则还仅仅局限于物质层面,对农民的心理和情感损失没有作出相对应的措施,这与社会的发展趋势不相一致,显然落后于整个社会的需求。本文简要分析了情感因素的内涵,同时结合我国当前征地补偿现状,对失地农民补偿中情感资本补偿的缺失做了深度分析,提出了情感资本补偿对失地农民的重要性和必要性,认为在以后的补偿体系中,将对情感资本的补偿纳入补偿体制仍将具有很大的可能性和可行性。 相似文献
3.
It is a hot question in recent years in China about the urban house dismantlement and development, and the low compensation standard of the urban house dismantlement has been thought to be the main reason that cause dispute of the urban house dismantlement. After a two-player game model is built, the paper solves mix-strategy Nash equilibrium of game and analyzes the influence of improving compensation to game equilibrium. It is concluded that, if government only improve policy of compensation standard to issue, the resident ready to move with their house to be dismantled can enjoy the great benefit shortly, but the long-term policy result is to reduce the incidence of the urban house dismantlement and slow down paces that the old city transforms. 相似文献
4.
THis Paper derscribes a novel all-fiber compensation network with three access-couplers for improving the stability of amplitude modulated fiber optical sensors. and its optimumstructure which is indepent on environment effects. We also describe the sealing method of the com-pensation network and the experiment of its coupler parameter variation caused by tempertare andvibration. The expreiment results showed that the compe nsation network can effectivelv resist themeasurement error affected by the in tensity variation of the optieal souce and other transmission loss. 相似文献
5.
关于完善西部生态补偿机制的建议 总被引:4,自引:0,他引:4
中国西部地区自然环境条件十分脆弱,随着经济开发强度进一步增强,有可能使本已遭到严重破坏的生态系统进一步恶化,导致经济社会的可持续发展能力不断削弱。分析了西部现有的生态补偿制度缺陷,提出完善西部地区现有的生态补偿机制是实现经济与生态协调发展的重要手段,也是实现西部可持续发展的关键 相似文献
6.
生态补偿对区域发展影响研究的进展 总被引:4,自引:1,他引:3
基于生态补偿项目设计的目标和项目实施产生的效应,有关生态补偿对区域发展影响的研究开始成为近年来国内外生态补偿研究中普遍关注的议题。本研究首先对国内外生态补偿的概念和研究机制进行了简要的回顾;然后分析了国内外关于生态补偿对区域发展影响的最新进展;最后提出了中国生态补偿项目在设计和实施过程中需要改善的问题,以期为促进生态补偿对区域发展的影响研究在中国的开展提供参考。 相似文献
7.
研究目的是通过分析土地补偿制度的功能及缺陷,为完善征地补偿制度提供一种思路。研究方法为定性分析法,规范分析。法研究结论为土地补偿制度的激励与约束功能失衡,导致政府滥用土地征用权,土地资源闲置浪费;配置功能的不健全,土地利用结构的不合理,使整体效益下降;社会保障功能的微弱、不配套,导致失地农民与政府的矛盾进一步激化,不利于社会稳定和经济的发展,国民富利水平的提高。 相似文献
8.
黑龙江省健全农业生态补偿制度初探 总被引:1,自引:1,他引:0
为建立系统的黑龙江省农业生态补偿机制提供参考,以达到合理利用资源、促进农村生态环境良性循环、推进经济社会协调与可持续发展的目的。通过分析得出的结论是:必须从黑龙江省实际出发,健全农业生态补偿制度,并要结合生态学、经济学等多学科,在深入实证调研基础上,着力探索一条适合黑龙江省的农业生态补偿道路。并从建立健全农业生态补偿的法律法规和标准体系、建立多中心视角下的生态补偿机制、建立“开源型”的补偿方式及建立农业生态补偿示范区4个方面对黑龙江省农业生态补偿制度提出建议。 相似文献
9.
10.
农业种植结构调整补偿政策研究 总被引:1,自引:0,他引:1
为解决中国农产品禁产区种植结构调整导致农户可能出现的损失问题,需要研究从国家层面制定补偿政策及补偿方案,以维护农户受损的利益。采用问卷调查的形式,对湖南省湘潭市400户农户开展了实地访谈,在此基础上,通过召开专家咨询会议,调研了种植结构调整试点的实施情况。从调查数据以及调研信息分析的结果来看,与一般意义上的农业生态补偿不同的是,种植结构调整补偿政策及补偿方案的制定涉及的内容更多,也更加复杂,其影响因素包括补偿主体、补偿标准、资金来源等,需要重新界定和解读,并根据实际的农业生产情况做出相应的调整。此外,与种植结构调整相配套的耕地治理技术尚未成熟,需要加大研发投入及开展试点工作,尽快形成技术标准和规范,并以法律条文的形式予以保障和支持。 相似文献
11.
The temperature drift is one of the most important error sources and influences the measuring accuracy of gyroscope greatly. The more exact temperature is measured, the more accurate angular error could be compensated. So the improvement of temperature measurement is significant to the system accuracy. A temperature measurement and compensation system was designed and experimented. The temperature of solid vibration gyroscope developed by ourselves was measured, analyzed and corrected. At last, the mean square deviation reduced from 31. 418 2 to 0.547 7, The experiment results proved that the design of soft and hardware is effective. 相似文献
12.
“城中村”改造过程中的房屋拆迁补偿问题调查与思考 总被引:1,自引:1,他引:0
摘要:“城中村”集体土地房屋拆迁补偿问题关系到城市的发展和村民的生存命脉。本文以郑州市金水区燕庄为例,对“城中村”改造过程中的房屋拆迁补偿政策和执行情况进行了实地调查。结果表明,燕庄“城中村”改造补偿过程中存在一些问题,如村民对补偿标准不满意、村民无法有效地了解政府的安置补偿政策、补偿费用不到位、过程不民主、村民有抵制拆迁和拒绝补偿的倾向等。建议通过法律约束、政策引导、社会保障和人文关怀等改进措施,保障村民权益,为城市化进程中的“城中村”改造提供参考依据。 相似文献
13.
Ecologic compensation system is the important policy and guarantee in returning the grain plots to forest. This article explains the necessity and significance of ecologic compensation in returning the grain plots to forest with externalities theory and supply-demand chart, analyzis currently ecologic compensation system, and points out some problems in ecologic compensation system nowadays. On the basis of above argumentation, the article brings out the improvement measures of ecologic compensation system ,designing the calculation method of scientific compensation standard. 相似文献
14.
粮食主产区利益补偿必要性分析——基于主产区与非主产区粮食生产及经济发展水平差距的视角 总被引:2,自引:1,他引:1
为了论证粮食主产区利益补偿的必要性,以河南省和广东省为例,从粮食主产区和非主产区在粮食生产及经济发展水平差距的视角进行了分析。结果表明:粮食主产区对中国粮食安全做出重要贡献,却在农民人均纯收入及地区经济发展水平上与非主产区存在巨大的差距,长此以往,势必影响主产区地方政府推动粮食生产及农民的种粮积极性,威胁国家粮食安全。因此,对粮食主产区进行利益补偿,在合理的成本下,使农民获得与从事其他生产大致相当的平均收益,使主产区能够获得与其对粮食安全贡献相一致的补偿,对保障国家长期粮食安全有着重要意义。 相似文献
15.
Li Jianshu Zhong Xianxin 《保鲜与加工》1999,(1):24-28
The paper analyzed the effect of disturbances that occur during transmission in the fiber and the influence of the selectivity of coupling implement on the fiber on the basic of experiment and theory. 相似文献
16.
农业生态补偿的原理与决策模型初探 总被引:3,自引:0,他引:3
农业生态补偿是确保农业生态可持续发展与农民经济利益平衡的关键,从经济学、社会学以及生态学的基本原理出发,阐述了农业生态补偿的理论依据,探讨了建立农业生态系统与社会经济系统的价值流循环互动的补偿决策模型。 相似文献
17.
It is difficult to distinguish the cheating and other malicious behaviours in the grid service trust evaluation. A trust evaluation model for grid service based on compensation is proposed.With market mechanism, service provider and demander present the expected profit and compensate price for their behaviours to maximize their own profit. The game theory is applied to balance the expected profit and compensate price. Based on the game theory, evaluation trade strategy achieves perfect Bayesian equilibrium. Service provider and demander can choose their own trade strategy to maximize profit. Theoretical analysis and simulation results show that the service demanders can abandon the cheating motivation voluntarily, while the service providers can make right decision to choose trust evaluation. Compared with the existing model, the precision and security of the trust evaluation is enhanced greatly, while the calculating and communication cost is reduced remarkably. 相似文献
18.
Z. Li J. Lin T. Zhang N. Zhang C. Mu J. Wang 《Journal of Agronomy and Crop Science》2014,200(1):66-76
Nocturnal warming has various effects on plant biomass production. To understand how biomass production of the dominant grassland species Leymus chinensis responds to summer nocturnal warming in the eastern temperate Eurasian steppes, we simulated summer nocturnal warming (+4 °C) using a phytotron system for 100 days operated based on the variation of diurnal temperatures over the past 12 years in the Songnen Grasslands. Our results show summer nocturnal warming significantly increased above‐ground biomass production of parent and daughter shoots as well as increased below‐ground root and rhizome biomass production; rhizome biomass increased faster than root biomass leading to an increase in the rhizome biomass to root biomass ratio. Nocturnal warming slightly increased the number of daughter shoots per plant, and significantly increased the number of buds in the below‐ground bud bank and the number and length of rhizomes per plant. Also, the dark respiratory and net photosynthetic rates, Jmax, the rate of triosephosphate utilization and chlorophyll fluorescence parameters (ΦPSII and qP) were significantly higher under nocturnal warming conditions. These findings show that nocturnal warming in this ecosystem improves individual biomass accumulation due to photosynthetic compensation, and may enhance the population density and productivity of L. chinensis by increasing bud number in the below‐ground bud bank during the early stage of ecological succession for grasslands dominated by L. chinensis. 相似文献
19.
研究目的:通过分析经营性建设用地征地补偿实行土地权益入股的可行性和实行此种方式应具备的条件,为完善中国征地制度,保护失地农民利益提供一种思路。研究方法主要是文献资料法和理性分析法。研究结论:从理论常识、法律依据、企业需求、农民需求、政府等方面分析对经营性建设用地征地补偿方式实行土地权益入股是可行性的,并提出了实行此种方式应具备的基础条件、前提条件、技术条件和法律保证。 相似文献
20.
失地农民几种主要补偿安置方式的比较分析 总被引:3,自引:1,他引:3
总结了目前中国存在的一次性货币补偿安置、重新择业补偿安置、农业生产补偿安置、入股分红安置、异地移民安置和“征地保障”安置方式等六种补偿安置方式,分析了不同补偿安置方式的利弊和适用的条件,最后指出以后的补偿安置不是采用单一的方式,而是根据不同地区社会经济发展水平以及处于不同年龄段的失地农民的不同需要,选择不同的组合方式。 相似文献