共查询到20条相似文献，搜索用时 906 毫秒
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山东省枣庄市山亭区桑村镇地处枣庄西北部,周围5公里内没有大型工厂,土壤肥沃,水质优美,是全市典型的无污染区,使无公害黄花菜(又称金针菜)种植获得了得天独厚的地理优势。因为种金针菜比种植其它农作物赚钱多(一般情况下,露地一级黄花菜卖到12元/千克,特级卖到15-16元/千克;大棚早期卖36-38元/千克。),且省时、省力,黄花菜便成了农民们的“香饽饽”。山亭区桑村镇王庙村青年农民、区农广校优秀学员陈家珍栽种的1亩黄花菜,年收益八千余元。现将其栽培技术介绍如下。1繁育壮苗黄花菜主要采用分株繁殖,时间在花蕾采毕后到冬苗萌发前,也可在冬苗枯萎后春苗抽生前的一段时间,但以前者为好。挖苗分苗时应尽量少 相似文献
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根据英国某权威医学杂志公布的美国军医的一项调查显示,部署在亚洲某地的美国海军陆战士兵中,90%都曾受到过攻击,大多数人都看到过战友阵亡或受伤.由于常期处于紧张状态和时刻面临危险,陆战队员的心理健康受到了严重的损害.该调查表明,1/6的上兵在完成任务后出现了心理问题,这个比例和"越战"时期不相上下. 相似文献
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底栖鱼类对水田上覆水中磷素动态的扰动效应 总被引：2，自引：0，他引：2
[目的]研究底栖鱼类泥鳅对水田上覆水中磷素动态的扰动效应,探讨生物扰动机制.[方法]基于模拟试验,使用离子色谱法和分光光度法,对比分析上覆水中磷素含量在有/无泥鳅活动时的差异.[结果]扰动组的TP、DTP和PP浓度在试验开始阶段与对照组无显著差异,在试验中、后期显著高于对照(P<0.05).扰动组要的PP/TP高于对照组,扰动组中TP浓度的增加主要是由于PP的增加,扰动组的DIP/DT在试验中、后期显著高于对照(P<0.05).[结论]底栖鱼类对水田上覆水中的磷素产生了扰动作用,增加了水稻生长可利用的的磷素养分.
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[Objective] The research aimed to investigate the bioturbation effects of benthic fish Misgurnus anguillicaudatus on phosphorus dynamic in overlying water of paddy field,as well as to explore the bioturbation mechanism.[Method]Based on simulation experiment,the phosphorus contents in overlying water were analyzed comparatively with and without Misgurnus anguillicaudatus by the using of ion chromatography and spectrophotometry. [Result] The concentrations of total phosphorus (TP),dissolved total phosphorus(DTP)and particular phosphorus(PP) in bioturbation group had no significant differences with those in control group in initial stage of experiment,and became significantly higher than control group in middle and late stages of experiment(P<0.05).The PP/TP ratios in bioturbation group were bigger than those in control group,the increase of TP concentration in bioturbation group was mainly due to the increase of PP.The ratios of dissolved inorganic phosphorus(DIP) to DTP (DIP/DTP) were significantly bigger than those in control group in middle and late stages of experiment (P<0.05). [Conclusion] The benthic fish had bioturbation effects on phosphorus in overlying water of paddy field,which increased the available phosphorus for rice growth. 相似文献
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王守红是安徽省临泉县长官镇人,在经历几次创业失败后,决定养牛.刚开始,王守红对养牛一窍不通,就去咨询畜牧专家,专家说:"养牛和养猪是不一样的,牛是草食动物,夏天你就多喂些青草,冬天就喂酒糟加青贮饲料."王守红跑到临泉一家酒厂,发现墙外扔掉的酒糟堆积如山,他如获至宝,雇辆大卡车,将酒糟拉回家. 相似文献
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氨基酸广泛应用于药品、饲料(鱼饲料、猪饲料)及添加剂,是氨基酸叶面肥的主要原料,武汉都兴农资有限公司开发出直接应用于农作物作肥料施用的"都兴隆"氨基酸原粉,其优点有:1.养分含量高内含17种氨基 相似文献
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加拿大的农业科技及其组织管理 总被引：1，自引：0，他引：1
本文详细介绍了加拿大农业科技体制改革及其组织,其总的研究发展方向由加拿大政府掌握.把科技政策、研究发展方向和国家需要结合起来通盘考虑,自上而下提出科研项目. 相似文献
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对秦汉时期中国与印度的交流进行考证,在丰富的史料基础上,研究了当时中印的交通状况与农业科技文化交流。 相似文献
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Pait CF 《Science (New York, N.Y.)》1963,142(3598):1422-1424
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Lykken L 《Science (New York, N.Y.)》1966,151(3715):1172-1174
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《山东省农业管理干部学院学报》2019,(6):139-140
近年来,在社会经济的不断推动之下,互联网技术得到了飞速发展,随之而来的则是网络文化的兴起,这对于高校思想政治工作带来了较大的冲击,但同时也是一种新的挑战;因而各高校要对网络文化树立正确的认知,将其与高校思想政治工作相互结合,因势利导,才能推动高校思想政治工作的不断深入。本文针对当前网络文化与高校的思想政治工作展开进一步的研究与分析。 相似文献
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A comparative study of small temperate lakes (<20 square kilometers) indicates that the mixing depth or epilimnion is directly related to light penetration measured as Secchi depth. Clearer lakes have deeper mixing depths. This relation is the result of greater penetration of incident solar radiation in lakes and enclosures with high water clarity. Data show that light penetration is largely a function of size distribution and biomass of algae as indicated by a relation between the index of plankton size distribution (slope) and Secchi depth. Larger or steeper slopes (indicative of communities dominated by small plankton) are associated with shallower Secchi depth. In lakes with high abundances of planktivorous fish, water clarity or light penetration is reduced because large zooplankton, which feed on small algae, are reduced by fish predation. The net effect is a shallower mixing depth, lower metalimnetic temperature and lower heat content in the water column. Consequently, the biomass and size distribution of plankton can change the thermal structure and heat content of small lakes by modifying light penetration. 相似文献