草坪根系层基质和氮肥类型对氮淋失的影响

Effects of Rootzone Materials and Nitrogen Sources on Nitrogen Leaching from Greens of Golf Course

为更好地了解高尔夫球场草坪施用氮肥对水环境的影响,在温室里模拟高尔夫果岭用PVC管建造4种基质类型的小型蒸渗仪播种建植匍匐翦股颖(Agrostis stolonifera L. cv. Penncross),出苗后施用Hoagland和Arnon营养液培育至成坪,成坪后选用速效氮尿素和控释肥丁异叉双缩脲进行氮肥类型处理,每两周施1.8 g.m-2N。结果表明:4种基质类型的草坪幼坪期都存在污染地下水的可能性,但随草坪的成熟而降低,其中改良沙基质的草坪可能性最小;速效氮肥处理的草坪氮的淋失显著高于缓释氮肥处理。综合比较,高尔夫果岭根系层采用改良沙基质、少量多次地施用缓释肥可以有效控制氮的淋失。

Nitrogen leaching of simulated golf greens was studied using PVC lysimeters filled with four rootzone mixture materials in greenhouse in order to investigate the effect of nitrogen fertilizers on grounder water in golf course. The creeping bentgrass （Agrostis stolonifera L. cv. Penncross） was sowed in 32 lysimeters and fertilized with Hoagland and Arnon nutrient solution at the rate of 100 mL/lysimeter every week for 8 weeks. And then 16 lysimeters were fertilized with readily water-soluble nitrogen fertilizer （urea） and another half were fertilized with control-release nitrogen fertilizer （IBDU） every two weeks at same rate of 1.8 g ·m ^-2 N for 24 weeks, respectively. In seedling stage, four rootzone mixtures were all likely to degrade groundwater quality. However the possibility decreased along with the turf maturity. Among four rootzone mixtures, fully amended medium sand was least possible to pollute groundwater. At the beginning, more N leaching occurred for the lysimeters treated with water-soluble nitrogen than those fertilized with control-release nitrogen. Nitrogen leaching could be effectively reduced by frequent nitrogen application, using slow-release nitrogen fertilizer at appropriate rate, and amelioration of sandy rootzone materials.