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31.
稻鳅共生种养模式试验研究   总被引:2,自引:0,他引:2  
[目的]稻鳅共生是典型的稻田综合利用模式,符合生态农业发展方向。通过对稻鳅共生生态系统的生理生态学机制开展试验研究,为进一步推广稻鳅共生种养模式提供科学依据。[方法]采用田间试验方法,以水稻单作为对照,研究了不同泥鳅养殖密度下的稻鳅共生对水稻农艺性状、土壤理化性质、水稻产量构成的影响,并对稻鳅共生种养模式进行了经济效益分析。[结果]与对照处理相比,水稻长势在株高、有效分蘖率、根长等方面有一定提高。养殖田水稻株高增高了3%,有效分蘖率提高了8%~11%,根长提高了8.8%~31.3%。在土壤理化性质方面,与对照相比,土壤容重降低了7.1%~21.2%,孔隙度增加了4.1%~14.7%。实验前后养殖田内土壤有机质增加了3.5%~26.5%,对照田降低了2.5%~5.8%。土壤肥力(氮、磷、钾)减少,但减少幅度小于对照处理。稻鳅共生种养模式下水稻产量提高了5%~25%,同时稻田增收泥鳅1 725~3 375kg/hm2,净收入为1.836 0万~2.307 0万元/hm2,经济效益提高了3.65~4.84倍。稻鳅共生种养模式中泥鳅的养殖密度为30万尾/hm2时稻田的生态效益和经济效益最佳。[结论]稻鳅共生有效改善了土壤理化性质,促进了水稻的生长,提高了稻田产量和产值。  相似文献   
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Studies that simultaneously explore the effects of sensory experience on consumer emotions and behavior are rare. This paper builds a model of buying behavior based on sensory experience, 570 valid questionnaires were obtained from coffeehouse customers. Using structural equation modeling and multiple regression analysis, this paper validates the concept model and verifies that sensory experience is a significant antecedent to buying behavior. This study indicates that certain sensory experiences significantly influence emotion. Emotion also plays a mediating role in the relationship between sensory experience and behavioral intentions. The findings are theoretically and practically profound as they address the relationships among sensory experience, consumer emotions, behavioral intentions, and buying behavior, as well as explore how the five senses affect emotions and buying behavior. This paper concludes by indicating managerial implications and research limitations.  相似文献   
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This paper studies the effect of station density on prices in the retail gasoline market in the Czech Republic. We estimate the impact of the number of competing stations in various driving-distance ranges around each station on prices. We find that station density has a negative effect on prices; the effect decreases with distance and is statistically significant up to six kilometers. This suggests that the retail gasoline market is local rather than national.  相似文献   
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This paper examines the international trade of a variety of genetically modified (GM) food products over a 27-year period (1984–2011) with data from the United Nations using the tools of social network analysis. The results indicate that each of the different crops have a distinctive pattern of trade that has changed over time due to a number of different factors. Also, trade in agricultural commodities became more diversified over time, dominated less by the United States and other nations central in the trade networks and trade in the individual GM crops was stable over time. Countries maintained their trading partners for specific crops, despite the adoption of the genetically modified varieties. The economic implications of these results are discussed for specific countries.  相似文献   
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Prior literature examined reciprocity in the context of value creation. However, research has yet to examine whether reciprocity exists in value sharing. To address this gap, the authors examine retailer’s reciprocal value sharing with its manufacturer in relation to new product introductions. The authors test, via a survey of retail managers, whether reciprocal value sharing is influenced by an interaction of manufacturer’s prior new product success with innovativeness of a manufacturer’s products and the frequency of new product introduction. The results indicate that a retailer’s reciprocal value sharing is greater when the manufacturer historically launched successful new products, and that this effect is decreased with the innovativeness of a manufacturer’s products but increased with the frequency of new product introduction.  相似文献   
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Copulas provide an attractive approach to the construction of multivariate distributions with flexible marginal distributions and different forms of dependences. Of particular importance in many areas is the possibility of forecasting the tail-dependences explicitly. Most of the available approaches are only able to estimate tail-dependences and correlations via nuisance parameters, and cannot be used for either interpretation or forecasting. We propose a general Bayesian approach for modeling and forecasting tail-dependences and correlations as explicit functions of covariates, with the aim of improving the copula forecasting performance. The proposed covariate-dependent copula model also allows for Bayesian variable selection from among the covariates of the marginal models, as well as the copula density. The copulas that we study include the Joe-Clayton copula, the Clayton copula, the Gumbel copula and the Student’s t-copula. Posterior inference is carried out using an efficient MCMC simulation method. Our approach is applied to both simulated data and the S&P 100 and S&P 600 stock indices. The forecasting performance of the proposed approach is compared with those of other modeling strategies based on log predictive scores. A value-at-risk evaluation is also performed for the model comparisons.  相似文献   
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Firms increasingly use games to interact with their customers. Yet, surprisingly little is known about whether, when, and how such “gamified” interactions engage consumers with a firm’s brand, thereby facilitating self–brand connections. Building on flow theory, we show that gamified interactions that are highly interactive and optimally challenging facilitate self–brand connections, because such games lead to emotional and cognitive brand engagement. A field study and three experiments across various product domains and game designs support our theory. We also identify conditions under which consumers do not become engaged with a brand, namely when firms restrict their decisional control either to voluntarily participate in the game (i.e., compulsory play) or to spend as much time as desired playing the game (i.e., time pressure). Our findings advance existing knowledge about the use of games in marketing and provide important implications for how marketers can harness their potential to build self–brand connections.  相似文献   
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