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作者评定了烧荒对3种牧草生产力的影响。整个生长季节,每2周测定一次蓝茎冰草、格兰马草和线叶苔的产草量,此外,亦测定了植被的盖度和土壤水份。产草量高低随不同牧草种类、采样日期和试验处理而异。春季烧荒使蓝茎冰草和格兰马草6月中旬至下旬的产草量增加,秋季烧荒亦有助于提高这两种牧草的产量,但其效果稍逊于春季烧荒。相对而论,春季烧荒对线叶苔的产草量影响不显著,而秋季烧荒甚至会降低其产草量。在北部大平原,烧荒可以作为增加牧草产量的有效措施之一,但为了获得最大限度之效益,必须慎重考虑家畜的放牧时间。
The authors assessed the impact of burning on the productivity of three forages. The production of bluegrass, gramagrass and leaf moss was determined every two weeks throughout the growing season, in addition to vegetation coverage and soil moisture. Yield levels vary with different forage species, sampling date and test treatment. Spring burns led to the increase of grass production of bluegrass and granged grass from mid-June to late June, and the burning of autumn also helped to increase the yield of both pastures, but the effect was slightly lower than that in spring. On the other hand, the effects of spring burns on the yield of moss were insignificant, while the fall burned even reduced its yield. In the northern Great Plains, burning can be one of the effective measures to increase pasture production, but in order to get the maximum benefit, livestock grazing time must be carefully considered.