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931.
分析了观光旅游对于农产品品牌传播的必要性、可行性,指出了绿色农产品生产企业实施观光旅游存在的障碍,提出了绿色农产品生产企业实施观光旅游的实施要点。 相似文献
932.
933.
近年来,我国水产品质量安全事件时有发生,对渔业的健康发展造成严重的影响。水产品的质量安全不仅影响到渔业的可持续发展,也直接关系到消费者的身体健康,其已成为我国最为关注的焦点之一。从养殖环境、渔药及饲料投放、行业标准、监管措施、养殖技术、生产者素质等方面分析了我国水产品质量安全问题产生的主要原因,阐述了解决水产品质量安全问题的现实意义,并提出了相应的解决措施。 相似文献
934.
935.
H7N9禽流感引起的恐慌使农产品质量安全危机不仅是产品质量危机,更可能演化为影响社会稳定事件的导火索,分析危机中流言的说服原理、产生的环境、流言的种类及传播路径,指出通过建立农产品质量追溯体系和跟现代移动通讯终端相结合,全环节、实时、真实地监督生产和发布信息,可以破解危机中流言说服的危害. 相似文献
936.
In recent years, the Chinese government has highlighted the importance of adopting hog safety/quality traceability, and a growing amount of research continues to entice firms to adopt traceability systems. In this study, a survey was conducted on a sample of pig slaughtering and processing firms in Zhejiang, China through personal interviews and emails. The aim of this study was to examine the determinants of firm behavior on the implementation of voluntary traceability systems with more stringent standards and controls than those of the mandatory system in China. The results revealed that motivation based on product quality improvement, capital ability and role perception (business type) had significantly positive relationships with a firm’s voluntary traceability. Other incentives, such as operation improvement, recall risk reduction, reduced occurrence of safety issues, and technical strength were not found to be supportive in our study. This study provides an opportunity to better understand the determinants of firm behavior on voluntary traceability, particularly in light of the fact that some Chinese firms are facing the threat of criminal action for the use of illegal additives and the abuse of Clenbuterol. Policy recommendations on encouraging the implementation of pork safety voluntary traceability by hog slaughtering and processing firms are also discussed. 相似文献
937.
近10年来小麦价格在国家政策主导下平稳趋涨,推动中国小麦生产迈上新台阶。2013年新麦上市后价格快速上涨,近期市场步入收购后期,价格高位企稳。2014年小麦最低收购价的公布日期将近,预计成本因素及市场看涨心态将会促使麦价稳中上行,但对后期行情预期也不宜过高。 相似文献
938.
BACKGROUND: It is important to understand the degradation of organic molecules in surface waters to ensure that risk assessments, intended to prevent adverse effects on human health and the environment, are robust. One important degradation mechanism in surface waters is photodegradation. This process is generally studied in laboratory test systems, and the significance of the results is then extrapolated to the field. The aim of this work was to assess how fluctuations in the composition of surface water influence the photodegradation rate of chlorotoluron. RESULTS: Photodegradation DT50 values in the lake (mean = 26.0 days) and pond (mean = 26.0 days) were significantly slower than in the river (mean = 6.8 days) and stream (mean = 7.3 days) samples. The DT50 values in the pond and lake samples were similar to the direct photolysis value (mean = 28.6 days). Photodegradation was significantly faster in the stream and river samples, suggesting that indirect photolysis was significant in those waters. Principal component analysis indicated a strong inverse correlation between nitrate concentration and degradation rate. CONCLUSIONS: Nitrate concentration had a strong influence on the rate of photodegradation, with increasing nitrate concentrations sharply reducing the DT50. However, this effect was restricted to a narrow concentration range and levelled off quite quickly, such that further increases in the nitrate concentration had no significant effect on the rate of degradation. Extrapolating photodegradation rates of chlorotoluron from the laboratory to the field should be relatively straightforward, provided the nitrate concentrations in the waters are known. Copyright © 2012 Society of Chemical Industry 相似文献
939.
黄瓜壮苗指标与辐热积关系的模拟模型 总被引:2,自引:0,他引:2
为预测温室黄瓜幼苗的健壮程度,该文探讨了黄瓜根冠比、G值(全株干质量与育苗天数之比)、壮苗指数3个壮苗指标与环境温度和辐射的关系,以2个不同生态型黄瓜品种‘津春4号’和‘戴多星’为试验材料,通过分期播种试验及回归分析,建立了以辐热积为尺度的温室黄瓜壮苗指标模拟模型,并利用独立试验数据对模型进行了检验。结果表明,根冠比与辐热积曲线拟合度差,G值模型的模拟值与实测值符合度低。在该试验条件下,这2个壮苗指标均不适宜用辐热积做变量进行模拟。黄瓜壮苗指数与辐热积曲线拟合度高。模拟结果与实测值之间的回归标准误差(RMSE)为0.0040,说明模型具有较高的预测精确性;壮苗指数的模拟值与实测值之间基于1∶1直线的决定系数(R2)分别为0.9854(津春4号)和0.9761(戴多星),F检验均达极显著水平,表明模拟值与实测值的符合度高。该研究建立的基于辐热积的黄瓜壮苗指数模型能较准确的预测黄瓜幼苗健壮程度,所用参数少,模型实用性较强,可为黄瓜育苗中幼苗健壮程度的预测提供有效方法,也可为黄瓜育苗中的温光管理提供决策支持。 相似文献
940.