黄河故道地区梨园生草栽培的生态效应

为了探讨生草对梨园栽培生态效应的影响,在梨园种植了不同的牧草,测定0～100cm不同土层的含水量、有机质质量分数、全N、速效P、速效K质量分数及土壤的pH值,同时,对果园的生物多样性、环境温、湿度变化进行观察。结果表明,生草降低了梨园土壤含水量,果树与草主要在0～60cm土层存在水分竞争;增加了0～20cm耕作层土壤有机质及N质量分数,种植白三叶可增加土壤K的质量分数,种植紫花苜蓿可增加土壤P的质量分数,pH值总体是降低的;20～80cm土层土壤有机质质量分数等指标均降低。生草可增加龟纹瓢虫、草蛉等天敌的数量,使环境温度下降2～3℃,湿度增加10%～15%,减轻了梨树病虫害的发生。梨园生草初期,应加强灌溉,并注意合理施肥。不同牧草应混合种植。

Study on the ecological effects of inter-planting herbage in pear orchards in the old flooded area of Yellow River

In order to study the ecological effects of the inter-cultivated grass in pear orchards in the old flooded area of Yellow River,different grasses were inter-planted.The content of soil moisture, total N, available P and available K, organic matter and pH value at different depth of soil layers(0 to 100 cm) were measured and the biodiversity and the changes of the environmental temperature and humidity in the orchards were analyzed.Results showed that the content of soil moisture was decreased;the water competition between grass and pear trees existed at the soil depth of 0 to 60 cm;the content of organic matter and total N was increased in the layer of 0 to 20 cm;the content of available K increased in the plot cultivated with white clover and the content of available P increased in the plot cultivated with alfalfa;the pH value declined;the content of organic matter etc decreased in the soil layer of 20 to 80 cm.In addition, inter-planting grasses could increase the number of the natural enemies for pear pests, such as Propylaea japonica,lacewing,etc, reducing the occurrence of pear pests.In the orchards cultivated with inter-plants the temperature was declined by about 2 to 3℃, humidity increased by 10% to 15% but at the early stage irrigation should be strengthened,and reasonably cultivating different grasses is necessary.