撂荒地生物除草效果及其对土壤肥力的影响

作为一种有效的除草方式,生物除草具有众多优势,研究生物除草后杂草的变化规律和土壤肥力变化特征,为生态农业的发展提供技术支撑。采取小区试验,通过设置不同生物组合模式在不同季节进行撂荒地的过渡放牧试验,分析除草前后杂草种类、杂草生物量、土壤性质的变化,从而筛选出简便高效的撂荒地除草模式。结果表明：鸡春季旱地除草效果和鹅冬季水田除草效果受到放养密度的影响,且鹅+鸡组合模式的除草效果好于其单一投放模式。鸡、鹅分别对旱地和水田除草后,土壤中有机质、铵态氮和有效磷含量均有所增加,但在不同季节增幅含量有所不同,pH值都有所下降;鹅+鸡组合模式在旱地和水田除草后,除pH值有所下降外,其余养分含量都有所增加。利用家禽对撂荒地进行除草不仅能够达到除草目的,且在一定程度上提升了土壤肥力水平,但需注意其粪便腐熟引起的土壤pH降低问题。

Biological Weeding in Abandoned Land: Effect and Its Influence on Soil Fertility

As an effective weeding method, biological weeding has many advantages. The change law of weeds and the soil fertility after biological weeding are studied to provide technical support for the development of ecological agriculture. In the localized experiment, overgrazing experiment in abandoned land was conducted in different seasons by setting up different bio-combination modes. The weed species, the weed biomass and the soil properties before and after weeding were analyzed, and the easy and efficient weeding mode was screened. The results showed that the weeding effect of chicken in dry land in spring and the weeding effect of goose in paddy field in winter were affected by stocking density, and the herbicidal effect of goose+chicken combination mode was better than any single mode. The contents of organic matter, ammonium nitrogen and available phosphorus in the soil increased after the weeding of chickens in the dry land and geese in paddy field, but the increasing amount varied from different seasons, while the pH value decreased. Applying the weeding of goose+chicken combination mode in dry land and paddy fields, all the nutrients’ content increased except pH value. The use of poultry to weed the wasteland can not only achieve the purpose of weeding, but also improve the soil fertility level to a certain extent, but attention should be paid to the soil pH reduction caused by manure decomposing.