脐橙果园杂草对地表径流和土壤流失的影响

江西省赣州市是我国最大的脐橙主产区,但长期以来果园水土流失问题未得到有效解决。试验于2015年3-8月雨季分别在江西省赣县和信丰县2个县各选择1个脐橙果园进行,在每个试验区果园设置3个径流小区,每个小区为1个处理,分别是清耕裸露(CK)、全园保留杂草(T1)和杂草条带(T2),观测地表径流和土壤流失情况。共调查到45种果园杂草,分属27科43属,其中马唐和宽叶雀稗为优势草种。径流小区观测结果显示,与清耕裸露地相比,果园全园保留杂草和杂草条带能减少地表径流量15.5%~50.3%、土壤流失量30.9%~45.4%,T1处理减幅总体比T2处理大。表明脐橙果园杂草在防治果园水土流失方面发挥着重要作用,值得深入研究。

Impact of Weeds on Surface Runoff and Soil Loss in a Navel Orange Orchard

The Ganzhou prefecture of Jiangxi Province is well known with its largest navel orange production area in China;however,soilerosion has been a long-time issue still to be resolved effectively. Field experiments were carried out in two orchards from two counties inGanzhou during the rainy season,from March to August 2015. In order to determine runoff and soil loss,three runoff plots in each experimental orchard were designed with three different treatments for every plot including absence of groundcover(CK),all weeds remaining(T1) and weeds belt(T2). There were 45 weeds species within the two orchards,belongingto 27 families and 43 genera,with crabgrass [Digitaria sanguinalis(L.) Scop.] and broadleaf paspalum(Paspalum wettsteinii Hackel.) as the dominant species. Compared with the CK,treatment T1 and T2 reduced runoff by 15.5~50.3% and soil loss by 30.9~45.4% respectively. In general,T1 was more effective than T2. The results demonstrate that orchard weeds play a significant role in soil and water conservation,thus shall be further studied in future.