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51.
通过对石家庄市农药企业现状调查研究,并结合国内国际的农药行业的现状及发展趋势,有针对性的提出了在环境危机下石家庄市实施产业结构调整、建立研发中心、促进企业合作升级、组建农药三废处理和包装回收中心系统等一系列具体措施,真正实现石家庄市农药行业的可持续发展。  相似文献   
52.
本文在广泛调查与深入分析的基础上 ,对山东省近两年的农药生产、科研、销售和应用情况进行了综述。为企业及有关部门提供了详实可靠的资料。  相似文献   
53.
现代企业契约理论对企业所有权分配的研究令人关注,并引起越来越多的争论。以前人的研究为基础,将剩余控制权进行了分割,提出企业所有权是剩余索取权与终极剩余控制权的融合体,并对所有权最优安排进行了讨论,认为股东拥有企业所有权是现实与理论逻辑的统一,利益相关者财富最大化目标理论基础并不可靠,实际操作更不现实。  相似文献   
54.
赵迪 《现代食品》2022,28(3):213-215
目的:调查分析2020年周口市所售蔬菜中有机磷类、氨基甲酸类、拟除虫菊酯类农药残留情况.方法:分别对2020年第二季度和第三季度周口市各蔬菜售卖点进行抽样,运用气相色谱法对各类蔬菜中3大类农药进行检测.结果:共检测蔬菜137份,检出含有农药残留的蔬菜19份,农药超标的5份,137份蔬菜农药残留检出率排序为鳞茎类>茄果类...  相似文献   
55.
    
Pesticides have long been important for the development of agricultural production. However, improper use of pesticides may result in inefficiency with respect to farm profitability, in addition to external effects of pesticide use on environmental and human health. This paper employs a production function that explicitly accounts for the role of damage abatement inputs (i.e. pesticides) in the production process, to examine the optimal use of pesticides. It then investigates determinants of pesticide overuse versus underuse and the intensity of overuse. The empirical application uses data on Vietnamese rice and fruit farms drawn from the 2016 Vietnamese Household Living Standards Survey. Results show about 95% of farmers overused pesticides for both rice and fruit farming systems. The Mekong Delta, also known as the ‘Rice Bowl’ of Vietnam, has higher levels of overuse on rice farms than two other regions. Overuse intensity is lower for female and poorer rice farmers while intensity is higher for those with more income and more family members. For fruit farms, younger farmers or those with more family members were more likely to overuse versus underuse pesticides.  相似文献   
56.
    
There is an increasing policy interest in pesticide taxation schemes as a measure to reduce harmful effects of pesticide use. The effectiveness of such tax depends, however, on the price elasticity of demand for pesticides. Moreover, information on these demand elasticities and their determinants is of crucial relevance for policy‐making and normative modeling approaches. In this article, we present a meta‐analysis based on studies that have estimated pesticide demand elasticities in Europe and North America. Our meta‐analysis reveals that the own‐price elasticities of demand for pesticides are, with a median of ?0.28, significantly smaller than zero, but also significantly larger than ?1, i.e. to be inelastic. We find that the demand for pesticides for special crops is less elastic than that for arable and grassland. In addition, the demand for herbicides is more elastic than for other pesticides. Studies that consider only short‐term horizons and little flexibility for farmers to adjust to price changes generate significantly less elastic pesticide demands. The results also indicate that more recent studies identify lower pesticide price elasticities of demand. Furthermore, we find that peer‐reviewed studies tend to find more inelastic results compared to grey literature.  相似文献   
57.
    
Researchers have spent substantial effort to identify factors influencing pesticide use intensity. However, few studies have compared the relative importance of these factors. This study examines four categories of factors that potentially influence farmers’ pesticide use decisions by evaluating incentivized experiment data, farm survey data, and remote sensing data in China. Our results suggest that land diversification has the largest effect on farmers’ pesticide use. Compared with the most rice-intensive landscape type, less rice-intensive systems cause farmers to spray less on middle rice. Heavy pesticide use intensity is associated with land fragmentation as small-scale farms still dominate crop production. Farmers’ integrated pest management knowledge has significant effects on pesticide use. We also find that loss and ambiguity preferences, rather than risk preferences, are more likely to affect pesticide use intensity.  相似文献   
58.
Land greening in China is regarded as contributing a great deal to greening of the Earth. The phenomenon is mainly attributed to climate change, arising atmospheric CO2 and ‘Grain for Green’ (GFG) land management policies. However, limited knowledge is known how much land greening is from contributions of the GFG practice. Therefore, the study took the typical region of the GFG practice, the Loess Plateau, as the study area, and used 1982–2015 satellite-observed GIMMS3g normalized difference vegetation index (NDVI) data, ERA-Interim climatic variables (precipitation, temperature and solar radiation) and atmospheric CO2 concentration data with the help of a developed TPRC-based NDVI model to derive GFG-induced NDVI after 1999. Furthermore, this study tracked the spatial-temporal dynamics of GFG-induced NDVI and assessed contributions of the GFG practice to regional vegetation changes. Results showed that satellite-observed NDVI and TPRC-based NDVI both exhibited an increasing spatial pattern from the northwestern to southeastern Loess Plateau, but their greening trends were separately 0.0022 and 0.0009 per year in 1982–2015 (p < 0.05). Note that the satellite-observed greening trend was much steeper with a slope of 0.0056 per year after 2006 (p < 0.05). The subsequent analyses documented that GFG-induced land greening were largely responsible for the steep trend. In space, evident greening patterns began to be observed in the central Loess Plateau from 2006 to 2008, afterwards expanded towards eastern and southwestern Loess Plateau. In 2011–2015, the increase magnitude of GFG-induced land greening in the Loess Plateau averagely accounted for 8.5 % in comparison to estimated TPRC-based NDVI, but in six natural zones were various, ranging from 3.2%–15.7%. In some regions of central Loess Plateau, GFG-induced NDVI contributed even more than 20 % to vegetation increase. This study highlights that land use management contributes more to land greening dynamics over the Loess Plateau compared to climate change and arising atmospheric CO2 concentration. These findings likely provide some valuable information for curbing or enhancing specific-location vegetation changes in future regional land management and planning.  相似文献   
59.
    
This study investigates how pesticide use by neighbouring farmers affects a given farmer's pesticide use. Although it is common knowledge that pesticide use has spatial externalities, few empirical economic studies explicitly analyse this issue. Applying a spatial panel econometric model to plot‐level panel data for Bohol, Philippines, this study shows that pesticide use, especially for herbicides, is spatially correlated, although there is no statistically significant spatial correlation in unobserved shocks. This implies that farmers apply pesticides by referring to the behaviour of neighbouring farmers rather than responding directly to the intensity of their own infestation.  相似文献   
60.
张天旭  李国  曹小彦 《现代食品》2021,27(3):154-157,161
利用QuEChERS技术结合液相色谱-串联质谱联用法建立同时测定植物源性食品中6种双酰胺类农药残留的方法.样品采用乙腈作为提取剂,在缓冲盐环境下经振荡提取,C18、PSA和GCB净化,样液过膜后经C18柱分离,在电喷雾离子源、正离子扫描模式下多反应监测方式检测,基质配标,外标法定量.6种双酰胺类农药残留在0.1~150...  相似文献   
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