Study on the initial planting density and its adjustment of Pinus sylvestris var. Mongolica Litvin. Artificial forest in the sand land.是什么意思_Study on the initial planting density and its adjustment of Pinus sylvestris var. Mongolica Litvin. Artificial forest in the sand land.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句