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花椒红胫潜跳甲(Podagricomela flavitibialis Wang)、花椒铜色潜跳甲(Podagricomela cuprea Wang)、花椒桔啮跳甲(Clites seiahatai Chuyo)三种跳甲都以成虫在花椒树冠下周围表土层7cm以内越冬。在花椒展叶后越冬成虫开始出土活动,4月下旬至5月中旬为产卵盛期孵化盛期,这一时期是药剂防治最关键时期。试验结果表明,花椒休眠期树冠下覆膜防治花椒三种跳甲效果显著,同时花椒树覆膜后抗旱保水、提高地温,也有明显的增产效果,且对环保无污染,安全可靠,操作简便,符合无公害农产品生产的技术要求。 相似文献
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[目的]揭示泥石流小流域降雨和土地利用对流域内坡面侵蚀的影响和作用,为泥石流的生态治理提供科学依据。[方法]以白龙江流域一级支沟——甘家沟泥石流小流域为研究区,基于该流域已建的5个径流小区(裸地、坡耕地、草地、土坎梯田、经济林地)连续5年的观测资料,利用K-均值聚类法,选择降雨量(P)、降雨历时(D)和最大30 min降雨强度(I30)3个降雨指标,将该流域46次侵蚀性降雨事件划分为3类雨型(Ⅰ型、Ⅱ型、Ⅲ型),以平均径流系数和平均土壤流失量为主要指标,定量化分析了不同降雨雨型和土地利用类型对坡面产流产沙的影响和作用。[结果]径流和土壤流失对降雨的响应存在差异,平均径流系数为Ⅰ型降雨最高,其次为Ⅲ型和Ⅱ型降雨;土壤流失量为Ⅱ型降雨>Ⅰ型降雨>Ⅲ型降雨。最大30 min降雨强度与5种土地利用类型的径流系数和土壤流失量的正相关性最高,其次为降雨量、降雨历时。5种土地利用类型的平均径流系数为裸地>经济林地>坡耕地>草地>土坎梯田,土壤流失量为裸地>坡耕地>经济林地>草地>土坎梯田。降雨和土地利用相互作用下,径流... 相似文献
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为明确不同成熟度油橄榄油品品质的变化规律,建立不同品种的质量体系,让企业和种植户能够根据自己的侧重点选择需要种植的品种,以提高生产效率和产品质量。以城固(Chenggu)、莱星(Leccino)、切姆拉尔(Chemlal de kabylie)0~7个成熟度的油橄榄果实为试验材料,对3个品种的出油率、酸价、过氧化值、多酚含量、主要脂肪酸等品质指标进行测定。结果表明,第7成熟度切姆拉尔的出油率最高,为13.6%;第0成熟度城固的最低,为2.1%。脂肪酸组成中油酸含量最高,为53.31%~71.64%;棕榈酸含量为12.91%~16.53%,棕榈一烯酸含量为0.42%~2.09%,硬脂酸含量为1.25%~2.96%,亚油酸含量为7.48%~18.24%;亚麻酸含量最低,为0.63%~1.51%。多酚含量,第1成熟度以城固最多,为281.91 mg/kg;第2成熟度以切姆拉尔最低,为73.53 mg/kg。多酚含量随着成熟度的增加会有一个先增加再减小的趋势;酸价(最高为0.67 mg/g)、过氧化值(最高为0.71 g/kg)远低于国标中对特级初榨橄榄油的限度。可见,3个油橄榄品种的油脂质量均比较高,其中切姆拉尔出油率较高,城固多酚含量较高。 相似文献
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Longnan City in Gansu Province is the largest base of olive production in China. In the olive orchard locating in Wudu District of Longnan City, thirty trees were sampled each of three cultivars, ‘Leccino’, ‘Chenggu32’, ‘Ezhi8’, with monoconical and vase training system. After planted with density of 5×6 m in 1992, each sample tree was investigated to determine the yield fresh fruit in five different years. The results of survey and analysis showed that there were significant differences of fruit yield among 5 years and 3 cultivars. Different canopy shapes yielded some effect on fruit setting rate and yield of different cultivars in different years. During first fruiting period in the fourth/sixth year after planting, fruit setting rate and yield of ‘Leccino’ with monocone were more 6.7% and 0.15 kg than those with vase and those of ‘Ezhi8’ and ‘Chenggu32’ with vase were more 20%, 10% and 0.18 kg, 0.09 kg than those with monocone. With the increase of tree age, fruit set and yield of ‘Leccino’ and ‘Ezhi8’ with vase was more than those of monocone. In 2011, average yields per tree of ‘Leccino’ and ‘Ezhi8’ with vase were more 13.35 kg and 6.85 kg than those with monocone. And the highest yield per tree of ‘Leccino’ with vase was 75 kg, more 16 kg than that of monocone. Fruit trees with yield over 35 kg of ‘Leccino’ and 25 kg of ‘Ezhi8’ with vase accounted for 80% and 46.7%, more 40% and 30.01% than those of monocone. It was concluded that vase training system would produce higher yield of ‘Leccino’ and ‘Ezhi8’ and its effect and advantages were gradually prominent with increase age. As for ‘Chenggu32’, monocone got a slightly higher yield than that of vase and in 2011 fruit trees with yield over 15 kg accounted for 25%, more 8.34% than vase. The difference between two training system of this cultivar was not obvious. 相似文献
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由于气溶胶的介电常数不易直接测量,气溶胶的复折射指数的实部与其介电常数之间存在的一定关系,利用这一关系,可以用气溶胶的复折射指数的实部来求出其介电常数,并对4种基本粒子、3种常见类型的气溶胶以及任意体积比混和建立的气溶胶类型的介电常数进行了研究。 相似文献