沙滩试验苗圃,地处白龙江支流拱坝河上游谷地冲积台,沟谷走向:东南—西北向,海拔2357米,属高寒山区,无霜期100—110天。过去培育落叶松、云杉苗木,播后多采用竹帘或荒草覆盖,地温低,发芽出土需30～50天,即4月下旬播种,5月下旬、6月上中旬方能出土;播种期提早或推迟,又易遭晚霜和日灼危害。为促使种子提前发芽,延长生长期,我们进行了塑料薄膜覆盖试验。 Beach test nursery, located in Bailong River arch dam upstream alluvial valley, valley to: southeast - northwest to 2357 meters above sea level, is an alpine mountain, frost-free period of 100-110 days. In the past, larch and spruce seedlings were cultivated. After the sowing, the bamboo or the weeds were mostly used to cover larvae and grassland. The ground temperature was low and the germination time was 30 to 50 days, that is, sowing in late April and late May and mid June. Early or delayed, but also vulnerable to night cream and sunburn hazards. In order to promote seed germination in advance, to extend the growth period, we conducted a plastic film covering test.