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221.
通过对海南椰子生产现状的分析,本文指出了建立优质良种椰子种苗生产示范基地的必要性和重要性,并针对一些需要解决的问题,提出了加快海南椰子产业发展的建议。 相似文献
222.
József Kiss Lászlóné Szendrey Eckart Schlösser István Kotlár 《Journal of environmental science and health. Part. B》2013,48(3):421-425
Abstract Oil products are widely used in orchards and on grapevine as pesticides, or adjuvants to pesticides. We aimed to get information on the efficacy of formulated rape seed oil against phytophagous mites in grapevine and its effect on predatory mites. Formulated rape seed oil (TELMIONR) from the Temmen GmbH, Germany was used in field trials at 0.5% and 1 %. For phytophagous mites TELMIONR had an efficacy of 90,1% and 91,2% for 05% and for 1%, respectively. For Phytoseiidae there was no side effect at 0.5% and 1%. For Tydeiidae there was no side effect at 0.5% and a moderate toxicity (43.1%) at 1%. On the basis of our results TELMIONR seems to fit well into Integrated Pest Management or Organic Production in grapevine. 相似文献
223.
224.
大庆贴不贴泡周边土壤及地下水石油烃污染规律 总被引:3,自引:3,他引:0
贴不贴泡是大庆某石油化工总厂生产废水排放场地,其作用相当于一个水面较大的氧化塘.在纳污泡周边分别采集土壤及地下水样品,以研究其对周边土壤及地下水的污染状况.结果显示:纳污泡附近地下水及表层土壤受到不同程度石油烃污染,但除第1个采样点外,其余各采样点污染程度随距离变化不明显;土壤纵向以40~60cm厚度层污染最为严重.说明大庆地区草甸黑土对石油烃滞留能力很强,使石油烃在其中的迁移速度很低,特别是水平迁移速度更小,才使污染近30年的场地地下水受到的石油烃污染不是十分严重.表层土壤的污染主要是由于雨季纳污泡内污水溢出造成的. 相似文献
225.
R. A. Chapman C. R. Harris J. H. Tolman D. Dubois 《Journal of environmental science and health. Part. B》2013,48(5):895-916
Abstract Potatoes were grown in Plainfield sand and muck treated, in furrow, with aldicarb (Temik 15G, 3.36 kg Al/ha). .Soils were contained in 2 mz field plots and had not been treated previously with pesticides. Soil, seed pieces, foliage and tubers were analyzed for the insecticide and its sulfoxide and sulfone metabolites during the 12 wk following planting. The disappearance of aldicarb from the soil was accompanied by partial conversion to the sulfoxide and sulfone. After increasing rapidly during the first 2 wk, the aldicarb concentration in the seed piece declined and a similar concentration of aldicarb sulfoxide accumulated which subsequently slowly disappeared. Aldicarb sulfoxide was the major insecticidal material in the new foliage. High initial concentrations, observed at 3–4 wk, declined by about 90% after 6 wk. Aldicarb sulfoxide residues of 2–4 ppm in the first new tubers at 6 wk declined by 90% by 12 wk. Potatoes were also grown under greenhouse conditions in Plainfield sand treated with Temik 10G at rates equivalent to 1.68, 3.36 and 6.72 kg Al/ha. Maximum aldicarb sulfoxide concentrations in soil, seed piece and foliage increased with application rate. The sulfoxide was much more persistent in the soil and foliage than in the field experiment indicating the importance of environmental factors to its behaviour in both soil and potato plants. 相似文献
226.
R. A. Chapman J. H. Tolman C. Cole 《Journal of environmental science and health. Part. B》2013,48(3):485-506
Abstract Potatoes were grown during 1992 in 2 m2 plots of loam which had received 1, 2 or 3 annual treatments of Di‐Syston 15G, equivalent to 3.36 kg AI/ha, in furrow at planting. The presence of enhanced degradative activity to the sulfoxide and sulfone metabolites of disulfoton in the soil treated in the previous two years was confirmed by laboratory tests prior to the 1992 treatments. Soil, seed potato and foliage from the three treatments were analyzed for disulfoton and its sulfoxide and sulfone metabolites for 12 wk following planting/treatment. Disulfoton was the major insecticidal component of the soil, a minor component of the seed piece and was not detected (<0.02 ppm) in potato foliage. Disulfoton concentrations in each of the three substrates sampled were similar for the three treatments. Disulfoton sulfoxide and sulfone were the major insecticidal components of the seed piece and foliage. Their maximum concentrations in 1st year soil, seed pieces and foliage were ca. 2x, 2x and 6x, respectively, those measured in the 2nd and 3rd year treatments. The results demonstrate that enhanced microbial degradation of relatively minor insecticidal compounds in the soil can profoundly affect insecticide levels in the plant when these compounds are the major insecticidal components accumulated. The broader implications for crop protection using soil‐applied systemic insecticides are discussed. 相似文献
227.
对川牛膝种子开展室温常规贮藏、室温湿沙贮藏、室温超干燥贮藏、4℃低温贮藏、冷冻贮藏等5种贮藏试验,结果表明:①室温湿沙贮藏是川牛膝种子短期保存的最优方法,能显著提高种子发芽率,其值较常规保存高14.5%;其次为4℃低温贮藏.②冷冻贮藏是川牛膝种子长期保存的最佳方法,保存3年后当其他保存方式的种子寿命几乎丧失时,其生活力及发芽率仍保持在较高水平,分别为60.3%和49.9%;其次为超干燥贮藏,种子生活力和发芽率分别为51.3%和41.2%. 相似文献
228.
Property rights and grassland degradation: a study of the Xilingol pasture, Inner Mongolia, China 总被引:1,自引:0,他引:1
The semi-private property rights arrangement called the Household Production Responsibility System (HPRS) was started in the early 1980s in Xilingol pasture of Inner Mongolia (China), and stimulated the development of stockbreeding. The grassland has been degrading severely with increasing numbers of livestock. Based on a historical review of property rights regimes in Inner Mongolia and empirical surveys in Xilingol pasture during 2001-2003, this paper assesses the implementation of HPRS and its impacts on incomes of households as well as the environmental impact on the grassland. It was found that HPRS does not mitigate the "Tragedy of the Commons", instead it has exacerbated the situation. It was also found that co-management of grassland and livestock among a few households presents a sustainable use of grassland to develop livestock breeding. We conclude with the recommendation that small-scale collective property rights systems should be encouraged in Xilingol pasture of Inner Mongolia. 相似文献
229.
《Journal of Manufacturing Processes》2014,16(1):123-136
Human welder's experiences and skills are critical for producing quality welds in manual GTAW process. Learning human welder's behavior can help develop next generation intelligent welding machines and train welders faster. In this tutorial paper, various aspects of mechanizing the welder's intelligence are surveyed, including sensing of the weld pool, modeling of the welder's adjustments and this model-based control approach. Specifically, different sensing methods of the weld pool are reviewed and a novel 3D vision-based sensing system developed at University of Kentucky is introduced. Characterization of the weld pool is performed and human intelligent model is constructed, including an extensive survey on modeling human dynamics and neuro-fuzzy techniques. Closed-loop control experiment results are presented to illustrate the robustness of the model-based intelligent controller despite welding speed disturbance. A foundation is thus established to explore the mechanism and transformation of human welder's intelligence into robotic welding system. Finally future research directions in this field are presented. 相似文献
230.
对LNG储罐泄漏事故进行危险分析,选用PHAST软件计算模型,针对LNG储罐不同事故类型选取最大设想事故进行假设模拟,确定了不同条件下LNG储罐泄漏事故的安全距离;对结果进行分析,得出的结论对LNG储罐的安全管理和事故预防提供了一定的参考。 相似文献