小学英语“1+N”课程资源建构研究

当今各国教育部都在聚焦人的核心素养的培养,而落实核心素养,需要以课程为依托,将核心素养转化为学生学习的生产力。这就要求我们必须建立一个适合学生整体、多元发展的课程体系。为此,在我校小学英语教学中,教师要基于每个年龄段学生的不同特点,努力开发丰富的个性化的课程资源,为学生提供多样化和发展个性的空间,最大限度地开发学生潜能,全面提升综合素质,为学生快乐学习、个性学习和全面发展提供坚实的基础。

Effects of different N sources on growth, nutrient uptake and ionic balance of Larlix gmelini seedlings

The effect of different sources and levels of N on dry matter production, nutrient uptake and ionic balance ofLarlix gmelini was studied. The results showed that the growth of the plants fertilized with ammonium was not as good as the control treatment. The growth of the plants fertilized with ammonium nitrate did not differ significantly from that in control or nitrate treatment, but was better than that in the ammonium treatment. Total cation concentrations in shoots varied little with N level in the ammonium and ammonium nitrate treatments, while those in the shoot increased with N level in the nitrate treatment. The treatments had little effect on the anion concentrations in the shoot. In the roots, the concentrations of both cations and anions changed little except for SO4 2? and Ca2+. There existed a higher carboxylate production in the plants fertilized with nitrate. The ratio between the production of carboxylate and the production of organic N Δ(C-A)/ΔNorg was constant with N supply in the plants receiving nitrate, but obviously declined with N supply for ammonium-fed plants. Δ (C-A)/ΔNorg values were intermediate between those of the nitrate and the ammonium-fed plants as for the mixed N source.

内陆河水资源利用模式的推论和讨论

作者试图从理论上对内陆河流域水资源多次重复用于灌溉进行公式推导,最后得出,在n次重复利用情况下,水资源毛引用量总和W毛与水资源量W之比(亦即水资源引用系数)k=[1-((1-η)αβ)n][/1-(1-η)αβ)],灌溉净耗水量总和W净=Wη。并举例说明,当渠系水有效利用系数由η=0.40提高到η=0.50时,下游绿洲区被迫超采地下水,导致终端湖泊干涸这一普遍现象。为了拯救绿洲和改善生态环境,提出"中、上游在节水中求发展"的方针,并修建专用输水工程,进行行政干预向下游输送必要的水量,有条件时从外流域向下游调水以拯救日益萎缩的绿洲。