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91.
松嫩平原北部黑土区水土资源平衡效应研究   总被引:1,自引:0,他引:1  
研究目的:分析松嫩平原北部黑土区在土地利用和农业气候资源变化条件下的水土资源平衡效应。研究方法:在傅抱璞假设理论的基础上,通过拟合参数ω回归方程求得实际蒸散量,以此来构建水分盈亏模型,分析水土资源平衡效应。研究结果:(1)1985—2015年,松嫩平原北部土地利用表现为湿地面积大幅度减少,水田和旱地面积不断增加;潜在蒸散量和气温具有较为明显的变化趋势,气温以0.27℃/10 a上升,潜在蒸散量以5.15 mm/a下降;(2)经过拟合参数ω方程求得实际蒸散量可以有效反映土地利用状况、地貌特征和土壤属性;(3)1985—2015年间总体的水分亏缺率均值是0.25、0.2、0.31和0.13,而土地利用的影响使严重缺水面积逐年增加,其增加量是总面积的1.59%,约是原有面积的2倍。研究结论:基于傅抱璞理论改进的参数ω能够提高地区实际蒸散量的估算精度,对区域水土平衡评价具有重要意义,为实现区域资源合理利用提供指导。  相似文献   
92.
The primary contributions of smallholders during the communist and early postcommunist periods have been food production and labour for large farms. Those conditions are changing, however, as modern farms require less labour and food supply may be imported. For most smallholders in Central and Eastern European and former Soviet Union countries, the postcommunist neoliberal environment has not brought significant improvement, and strong arguments can be made that land grabbing, social and economic exclusion, and rural poverty are worse than regime bias during the communist period. Cooperatives, which have empowered smallholders in other parts of the world, have not been as well developed in postcommunist nations.  相似文献   
93.
This study analyzes the spatial dynamics in productivity growth and its components for a sample of agri‐food companies in Murcia (Spain) over the period 2005–2014. We find that productivity growth of a company is related to productivity growth of neighboring companies, in both the short and long term. The marginal effects of the different factors on productivity growth are stronger in the short run rather than in the long run. Land characteristics and economic territorial conditions have the largest marginal effect on productivity growth and its components. This study contributes to the existing literature by including spatial interactions in the analysis of productivity growth.  相似文献   
94.
An economic recession is a type of crisis originated from external factors that may imperil an organization’s survival depending on the intensity and duration of the crisis. In peripheral European countries, such as Portugal, the recent financial crisis had devastating effects on various business activities. As a result, Portugal represents an important case study in examining how some corporate leaders have handled the economic recession successfully. I interviewed 20 corporate managers to capture their perceptions of the leadership traits and behaviors exhibited by their CEOs in guiding their companies through the recession. In economic recessions, negative constraints do not affect the most effective leaders, who instead erect barriers against the high-pressure conditions to create a supportive, positive work environment. In order to achieve maximum effectiveness, leaders must act as blocking agents against the negative social impacts of the economic crisis, including the fragility of trust in organizational life (i.e., a barrier against distrust), uncertainty of the future (i.e., a barrier against uncertainty), and toxic emotions (i.e., a barrier against toxic emotions).  相似文献   
95.
It is important to understand customer dissatisfaction in order to maintain a sustainable business, given that the negative effects of customer dissatisfaction in service businesses may be even greater than the positive effects of satisfaction. This study investigates customer dissatisfaction and its consequences by focusing on the mediating role of attitude toward a hotel according to different hotel classes related to customer expectation level. The results show a mediating role for attitude in the relationship between customer dissatisfaction and specific negative behavioral intentions. This study broadens our knowledge of customer dissatisfaction and the role of attitude toward a hotel in the relevant literature. The empirical findings demonstrate that regardless of hotel type, customer dissatisfaction significantly affects their attitude and their consequent negative behavioral intention.  相似文献   
96.
Many hotels have launched their own branded mobile applications to develop relationships with customers. Yet, research examining the benefits of branded hotel apps on brand loyalty is scant. The current research investigates the role of branded hotel apps on brand loyalty through customer engagement and brand trust in the hotel industry, based on uses and gratifications theory. Results identified cognitive and social benefits of the branded hotel apps positively influenced customer engagement and brand trust. Hedonic benefits positively influenced customer engagement and they indirectly influenced brand trust through customer engagement. Both customer engagement and brand trust positively influenced brand loyalty. Moreover, mediation effects of customer engagement and brand trust were identified. Results highlight how branded hotel apps serve as a facilitator of brand loyalty, providing theoretical and managerial implications.  相似文献   
97.
党的十九大报告提出了“实施乡村振兴战略”。乡村振兴是“中国梦”不可或缺的组成部分,城市化进程中的乡村衰落现象不容忽视,乡村问题的解决关系到乡村振兴战略能否实现和现代乡村能否建成。为此,剖析了我国乡村衰落的成因,探索了乡村振兴战略落实的办法,提出了现代乡村建设的可能路径。  相似文献   
98.
将水权交易和面源污染控制有机结合,以种植面积、农业用水定额、污染物浓度为约束条件,运用边际分析方法建立农户灌溉施肥行为模型,分析水权交易和排污控制对农户行为的影响。结果表明:灌溉用水量与农作物价格成正相关,与交易水价和边际灌溉成本成负相关;一定范围内肥料施用量与农作物价格成正相关,与边际施肥成本或边际环境成本成负相关。模型证明,当农业用水定额内水权可交易时,水市场的存在和水价政策将激励农户减少灌水量,节约用水。  相似文献   
99.
A separation between the academic subjects statistics and mathematical statistics has existed in Sweden almost as long as there have been statistics professors. The same distinction has not been maintained in other countries. Why has it been kept for so long in Sweden, and what consequences may it have had? In May 2015, it was 100 years since Mathematical Statistics was formally established as an academic discipline at a Swedish university where Statistics had existed since the turn of the century. We give an account of the debate in Lund and elsewhere about this division during the first decades after 1900 and present two of its leading personalities. The Lund University astronomer (and mathematical statistician) C. V. L. Charlier was a leading proponent for a position in mathematical statistics at the university. Charlier's adversary in the debate was Pontus Fahlbeck, professor in political science and statistics, who reserved the word statistics for ‘statistics as a social science’. Charlier not only secured the first academic position in Sweden in mathematical statistics for his former PhD student Sven Wicksell but also demonstrated that a mathematical statistician can be influential in matters of state, finance as well as in different natural sciences. Fahlbeck saw mathematical statistics as a set of tools that sometimes could be useful in his brand of statistics. After a summary of the organisational, educational and scientific growth of the statistical sciences in Sweden that has taken place during the last 50 years, we discuss what effects the Charlier–Fahlbeck divergence might have had on this development.  相似文献   
100.
This article argues that copyright is a systemic marketplace icon because of the breadth of its effects on market operations. Copyright determines how intellectual property rights for creative work are allocated between the different actors involved in production and consumption, and must balance the civic priority of public access to creative work with the market-driven principle of rewarding private interests for their effort. This duality tends to polarise opinion about its implementation by rights holders, because very different ideological assumptions underpin civic and market objectives. Copyright discourses reveal how these ideological struggles play out among interested parties, who use the concept of copyright to make arguments about how markets should be structured, how creative work should be exchanged, and how consumers should behave. In the process, copyright is constructed, explained, branded and promoted as an object to which market actors must orient themselves if they wish to conduct themselves appropriately, and as a rationale for material changes to market structures. At the same time, copyright discourses reveal the implications of copyright, which invoke both the market and democracy, for the quality of democracy, the circulation of creativity, and the availability of public knowledge, and help explain why ideological struggles over copyright are so difficult to resolve.  相似文献   
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