无人机遥感系统的研究进展与应用前景

对于无人机遥感来说,融合了无人机技术与遥感技术。在无人机遥感技术应用的过程中,涵盖了诸多不同类型的先进技术,比如,无人机驾驶飞行技术、通讯技术、遥感传感器技术等,存在着显著的智能化、自动化等不同方面的特征,能够迅速得到相关资源,并且系统掌握国土、环境等不同方面的信息,然后加以实时化处理,通过建模与科学分析,能够制定出无人机遥感技术运用的具体策略,凸显出其良好的功效。本文针对无人机遥感系统的研究进展进行了详细地分析,同时说明了无人机遥感系统的应用前景,进而对有关研究人员形成一定的启发。     

System of crop intensification for more productive,resource-conserving,climate-resilient,and sustainable agriculture: experience with diverse crops in varying agroecologies

With continually increasing demand for food accompanied by the constraints of climate change and the availability and quality of soil and water, the world’s farmers are challenged to produce more food per hectare with less water, and with fewer agrochemical inputs if possible. The ideas and methods of the system of rice intensification which is improving irrigated rice production are now being extended/adapted to many other crops: wheat, maize, finger millet, sugarcane, tef, mustard, legumes, vegetables, and even spices. Promoting better root growth and enhancing the soil’s fertility with organic materials are being found effective means for raising the yields of many crop plants with less water, less fertilizer, reduced seeds, fewer agrochemicals, and greater climate resilience. In this article, we review what is becoming known about various farmer-centred innovations for agroecological crop management that can contribute to agricultural sustainability. These changes represent the emerging system of crop intensification, which is being increasingly applied in Asian, African, and Latin American countries. More research will be needed to verify the efficacy and impact of these innovations and to clarify their conditions and limits. But as no negative effects for human or environmental health have been identified, making these agronomic options more widely known should prompt more investigation and, to the extent justified by results, utilization of these methodologies.     

Drivers of innovation in groundwater governance. The links between the social and the ecological systems

Global groundwater overexploitation positions groundwater governance as a critical issue for improving sustainable water management. Evidence of aquifer recovery after overexploitation is scattered, as is the research on the drivers behind recovery. The Fuencaliente Aquifer in Spain faced a tragedy of the commons situation, but after an innovative governance arrangement was implemented, the aquifer is gradually recovering. In this research, we identify the drivers that made possible the emergence and acceptance of such an arrangement using the social-ecological system framework. We identified external drivers such as market incentives and limited enforcement capacity of the water authority as the main factors that led to groundwater depletion, but we also found that these same drivers, under a new regulatory framework that reinforced monitoring and sanctioning capacities, are the basis for the effective recovery of the aquifer. Internal drivers such as the socioeconomic attributes of the users, their limited collective action and the power differences between traditional and commercial farmers are also critical in explaining the acceptance of the new governance arrangement. Even if these drivers are context-specific, we identified innovations that might be transferable and contribute to the literature on good practices in groundwater governance and management.     

Research on a diagnostic system of rural vitalization based on development elements in China

In 2017, the Chinese government implemented a national strategy of "Rural Vitalization" that sought to realize full-scale rural vitalization. However, is it possible to achieve vitalization for all the villages in China? How should their development potential be determined? This paper identified and analyzed the "element-composite" messages of rural development based on 99 exemplary sites of “Beautiful Villages” in China. Combined with the projection pursuit classification method, a diagnostic system of rural vitalization was established; then, Dehua County was taken as a case study for an in-depth analysis. Based on national data analysis, the final results indicated that livelihood resources (LR), agglomeration effects (AE), location and transportation (LT), cultural/natural landscapes (CN), and economic circumstance (EC) are essential elements for successful rural development. Additionally, EC was the only exogenous element, while the remaining elements were endogenous. Furthermore, the villages with better EC presented urbanization rates of 38∼82 % and Engel coefficients of 29∼41 % in their counties; exemplary sites lacking LR, CN, LT, and AE account for 13.13 %, 19.19 %, 26.26 %, and 60.61 % respectively, so the indispensability of these elements decreases progressively in sequence. Only 2 % of villages rely on single element for success, therefore, the composite pattern of development element was also critical; 10 out of 16 types were found to successfully facilitate village development, among which, the type of R-a-L-C (32.32 %) and R-A-L-C (15.15 %) were considered as the greatest potential patterns for vitalization. Finally, by means of the diagnostic system, the ratio of representative villages for high-low potential in Dehua County is evenly split; then, development paths, and land use policies that match with paths were proposed, on the basis of development potential and “element-composite” condition of themselves.     

Labor migration and the decoupling of the crop-livestock system in a rural mountainous area: Evidence from Chongqing,China

Massive out-migration of rural labor force brings both challenges and opportunities to crop-livestock integrated production system (crop-livestock system) in smallholder economy. Compared with previous researches that have paid major attention to the effect of labor migration on either crop production or livestock husbandry, this study considers the mediating role of crop production in predicting the effect of labor migration on livestock raising. Our econometric estimation based on a 2012 survey of 974 rural households in Chongqing, a mountainous region of China, showed the following. (1) The massive migration of rural labor force had led to significant increase in farmland abandonment and considerable changes in the pattern of livestock raising. (2) The livestock raising number per household began to differentiate, with the livestock system separating from the traditional crop-livestock system and becoming a specialized business. (3) In terms of the pathways through which rural labor migration exerts impact on livestock raising number, though the increased opportunity costs of rural labor greatly reduced farmers’ willingness to raise livestock, the decoupling of the crop-livestock system partly alleviated the declining trend in the livestock raising number because of the availability of household labor force freed from cropping via farmland abandonment. These findings have important policy implications for rural development and agricultural restructuring in mountainous areas of China, and provide references for other developing countries.     

When profession trumps potential: The moderating role of professional identification in employees’ reactions to talent management

Abstract

This study aimed to investigate the role that a professionalized context plays in shaping employee reactions to talent management decisions. We examined the mediating role of felt obligation in the relationship between talent ratings and organizational citizenship behavior. Further, the study tested whether professional identification moderates the relationship between talent ratings and felt obligation towards the organization. Five hundred and ninety-eight teachers that had recently received ratings of their talent status responded to a survey questionnaire. Felt obligation mediated the relationship between talent ratings and organizational citizenship behavior. Furthermore, professional identification moderated the relationship between ratings of potential and felt obligation in such a way that the relationship was strongest for the teachers expressing the lowest professional identification. At high levels of professional identification, the relationship was not significant. These results indicate that conventional talent management might be less effective for increasing favorable attitudes and behaviors among employees in highly professionalized contexts, such as the education sector.     

Pains and gains of environmental management system certification for the sustainable development of manufacturing companies: Heterogeneous effects of industry peer learning

Environmental sustainability is a growing global concern. Environmental management systems (EMS) could be an effective strategic tool to help firms deal with their sustainable development. However, whether EMS certification pays off financially and how it takes effect can be debated. Thus far, these questions remain largely under‐researched. In particular, the effects of EMS certification on financial performance are inconclusive, and the reasons explaining the effects are underdeveloped. This study aims to enrich the current research by exploring the mediating and moderating roles from the perspective of cost‐efficiency trade‐offs to reveal how EMS certification affects financial performance. Applying a PROCESS procedure analysis and causal mediation analysis to a sample of 1,751 Chinese listed manufacturing firms from 2008 to 2016, this study shows that the effect of EMS certification on firms' financial performance is insignificant because their operating costs burden increases while their marketing efficiency and managerial efficiency improve. For the first time, this study demonstrates the moderating role of industry peer learning, as the mediating effects decrease with the growth of industry peer learning.     

化肥价格变化对粮食价格的影响研究--基于省际动态面板数据模型的系统GMM检验

基于我国粮食价格与化肥价格变动趋势的分析,运用2006年~2017年省际动态面板数据模型和系统GMM方法,实证检验了化肥价格变动对粮食价格的影响。结果表明:化肥价格变动对粮食价格存在显著的正向影响,在考虑化肥价格影响下,农业生产服务、种子等农资价格对粮食价格也存在显著的正向影响,机械化农具和农药价格对粮食价格不显著,"价补分离"政策对粮食价格存在显著负向影响。因此,在化肥减量行动背景下,适度调控化肥价格,避免化肥价格上升挤占粮农利润,大力发展农业生产性服务业和种子业,继续实行"价补分离"政策,提高补贴精准性,减少农民投入成本。     

基于BP人工神经网络中国光伏产业贸易摩擦预警研究

建立有效的贸易摩擦预警系统有利于中国新兴产业的健康发展,有利于中国实施制造强国战略。将警兆信号法与人工神经网络相结合,从宏观经济形势、产业供给能力、双边贸易状况、市场需求水平等四个维度切入,构建了中国光伏产品出口贸易摩擦预警系统模型。预警分析表明,模型的预警效果与现实拟合较好,具有可行性。从模型的预警结果来看,2019年~2020年中国输美光伏产品贸易摩擦警情均低于轻警级别,仍面临一定的贸易摩擦风险。     

网购食品消费者选择行为的影响因素

利用1 790份网络调查问卷数据,采用相关分析、交叉分析等统计方法,研究网购食品消费者选择行为,分析网购食品市场渗透率不高、用户黏性不足的主要原因,结果表明,消费者个性特征差异会导致对网购食品的不同态度,进而影响消费者对网购食品的选择行为;良好的网购环境、物美价廉的食品、优质的网购服务,是促使消费者选择网购食品的主要因素,对网购食品安全的担忧、习惯于传统购物方式、网购维权难度大,是抑制消费者选择网购食品的主要因素,尤其是网购食品"难维权、维权难"可能会放大消费者对网购食品产生的消极态度。为此,应加强网购食品多主体协同监管,消除消费者怀疑心理和不放心态度;建立以消费者需求为中心的网购食品质量安全供应链管理体系,推动线上市场和线下实体店紧密结合、融合发展;完善网购食品维权制度,畅通维权渠道。