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91.
以科学发展观为指导,针对安徽省农民增收和农业发展中存在的资源约束等问题进行分析,提出了抓住时机,依靠政策调动、布局优化、市场带动、科技拉动,提高农民增收的稳定性和持续性,大幅度提高农民增收的对策和发展思路。  相似文献   
92.
预算实际上是一种建模,即根据过去和现在已有的信息建立一个从过去引伸到未来的模型。而时序分析法和灰色系统理论是两种有效的预测方法。为此,介绍了这两种预测方法的原理,并预测了新疆兵团的农机情况。其结果表明:未来10年,新疆农机总动力和投入将会有较大幅度的增长,而农业机械化程度将趋于最高值。  相似文献   
93.
Crop tolerance to land submergence is an important criterion for designing a surface drainage system for agricultural lands. This paper collates the available data from various places in India related to the studies on the submergence tolerance of crops. The paper hypothesizes that a piecewise linear model could be used to describe crop response to land submergence. According to this hypothesis, there would be no yield decline for a few initial days of submergence. If submergence continues beyond this period then there would be linear decline in yield. The unknown parameters in the model are: optimum yield, threshold time and the slope which represents the per cent yield reduction per day of additional submergence beyond the threshold.Data in respect of wheat, pigeon peas, cowpeas, pearlmillet, maize and groundnuts indicate that the model describes the data well, although in many cases the threshold is 0.0. The yield reduction varies from 5.3 to 23.2% for each day of submergence beyond the threshold. It appears that to allow for more than 1–2 days of submergence will result in more than 10% reducation in yield of dryfoot crops. For the maize crop, the seedling stage is the most sensitive stage followed by the silking stage. The grain formation stage is the least sensitive, although even at this stage the threshold is 0.0 and yield reduction is 9.3% for each day of submergence beyond the threshold. The data for 9 test crops from Texas and Venezuela were well described by the model. It is concluded that the piecewise linear model is a useful tool for describing submergence tolerance of crops and for working out surface drainage requirements for a given level of yield reduction. Frequency analysis of the daily rainfall data from some selected locations indicates that there is every likelihood of submergence at most of the stations. It is suggested that there is an urgent need for developing wet farming techniques analogous to dry farming techniques.  相似文献   
94.
为解决随着大、中型联合作业机具和跨区作业的发展.农村中占机具总量大部分的小型机具出现闲置.造成了农机资源的浪费问题,提出了4条提高利用率的途径和农机主管部门应做好的5项工作。  相似文献   
95.
河北省机械化旱作节水农业技术及发展对策   总被引:1,自引:0,他引:1  
阐述了河北省机械化旱作节水农业的现状;介绍了目前正在全省实施的几项主要机械化旱作节水农业技术;提出了发展机械化旱作农业技术的几项对策。  相似文献   
96.
根据基于单片机系统的农业仪表的使用需要,设计实现了农业仪表与PC机间的标准通用通讯接口。叙述了在单片机中为进行与PC机通讯而设计的硬件电路及相应的软件设置。同时也阐述了在PC机Windows环境下与农业仪表进行通信的方法步骤。在设计中对芯片的选择、电路原理、软件设计及协议规范等方面进行了比较全面的分析。  相似文献   
97.
GIS在农业水土领域的应用与研究进展   总被引:5,自引:0,他引:5  
介绍了近年来国内外GIS在农业灌溉管理、精确农业和农业区划、土壤利用和土壤侵蚀方面的研究和应用情况,并对GIS在该领域的研究进行归纳和总结,此外探讨了GIS在当前农业领域应用的主要发展方向。  相似文献   
98.
对汽车中控锁电动执行器性能检测进行了深入研究。通过力学分析与试验,对交变试验力的特点及产生原因进行了分析,得出盘簧机构相对电动执行器是交变负载,从而提出了以中控锁自身作为检测负载的方案。为解决在恒温箱内测量主动驱动力的困难,采用了间接测量工作电流的方法;此外还进行了耐久性试验和驱动时间的测量。全套检测装置已成功应用于生产中。  相似文献   
99.
There is a widespread consensus about the importance of sustainable agriculture. In France, the Farming Orientation Law of July 1999 has set down a precise procedure for the implementation of sustainable agriculture: the contrat territorial d’exploitation – or territorial farm contract (TFC). This paper aims to analyse the TFC effectiveness. An analysis has been made of the TFCs signed in the Midi-Pyrenees Region in south-western France, using statistical analysis and qualitative surveys of a sample of farms. The results show that the most valuable effects have been mainly economic. Effects regarding social and environmental aspects were very limited. But from the point of view of an integrated approach, indirect effects of TFCs can be observed on social and environmental aspects. These results are explained, on the one hand, by farmers’ motivations guided by economic objectives, and on the other hand, by the dominance of professional farming organisations in the implementation of TFC’s procedure. Given these results, two ways of improving the elaboration procedure for TFCs are proposed. Firstly, technical improvements can be made to the diagnostic assessment of farms, and to the choice of actions addressed by the contract. Secondly, organisational improvements can be applied to TFCs elaboration and implementation process, in order to adopt a participatory approach which would involve all rural stakeholders.  相似文献   
100.
Whole-farm design models quantitatively analyze the effects of a variety of potential changes at the farm system level. Science-driven technical information is confronted with value-driven objectives of farmers or other social groupings under explicit assumptions with respect to exogenous variables that are important drivers of agricultural systems (e.g., market conditions). Hence, farm design is an outcome of objective specification and the potential of a system. In recent publications, whole-farm design modelling has been proposed to enhance (farm) innovation processes. A number of operational modelling tools now offers the opportunity to assess the true potential of whole-farm design modelling to enhance innovation. In this paper, we demonstrate that it is not trivial to find niches for the application of goal-based farm models. Model outcomes appeared not to match questions of farm managers monitoring and learning from their own and other farmers’ practices. However, our research indicates that whole-farm design modelling possesses the capabilities to make a valuable contribution to reframing. Reframing is the phenomenon that people feel an urge to discuss and reconsider current objectives and perspectives on a problem. Reframing might take place in a situation (i) of mutually felt dependency between stakeholders, (ii) in which there is sufficient pressure and urgency for stakeholders to explore new problem definitions and make progress. Furthermore, our research suggests that the way the researcher enters a likely niche to introduce a model and/or his or her position in this niche may have significant implications for the potential of models to enhance an innovation process. Therefore, we hypothesize that the chances of capitalizing on modelling expertise are likely to be higher when researchers with such expertise are a logical and more or less permanent component of ongoing trajectories than when these researchers come from outside to purposefully search for a niche.  相似文献   
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