低山丘陵地区林草结合立体开发模式调查浅析

THE INVESTIGATION OF STEREO DEVELOPING MODEL TO COMBINE WOODS WITH GRASSES IN LOW MOUNTAIN HILLY AREA

低山丘陵地带在黑龙江省占有相当大的比例，其山坡上的天然植被资源早经开发利用，并已趋殆尽。碾子山区自１９９０年开始，对低山丘陵进行二次深度开发，采取在“山顶人工造林、山腰开辟林间草场、山脚和山川种粮”的多层次立体构造，使高树与矮草紧密结合、山上与山下协调发展。经过３～５年的造林育草，使牧草产量提高５～７倍，近期可获得草牧业收益，远期有林果业收益，不仅发挥出长短期相结合的经济效益，而且还显露出防止水土流失、改善气候、美化环境的生态效应，为北方低山丘陵的合理有效地进行二次开发利用提供较佳模式。

Low mountain hilly area accounts for a quite big proportion in Heilongjiang Province,andthe natural vegetation resources have been developed for a long time and nearly used up. The sec-ond deep development has been being since l990 in Nianzishan area. To adopt stereo structure ofdifferent levels i.e. artificial afforestation on the top of the mountain and starting grassland inforest on the half way up the mountain and planting crops on the foot of the hill, so as to combinetalI trees with low grasses and harmonize all over the mountain, After afforestation and growinggrass three to five years,the yield of forage grasses increased by five to seven times. Therefore,there will be grasses obtained in the near future, and there will be fruits at specified future date.Not only was the economic benefit brought into play but ecological effect of defending soil erosionand improving climate and beautifying the environment had been appeared. It has provided a bet-ter model for the low mountain hilly area of northem China.