Impact of mechanical and chemical weeding on the floristic diversity of citrus orchards in Tlemcen (Northwestern Algeria)

Abstract

This study was conducted to evaluate the impact of weeding (chemical, mechanical and control) on the floristic composition of citrus orchards in the region of Tlemcen (Northwestern Algeria). A comparative approach between two methods of weeding (mechanical vs. chemical) compared to a control (without weeding) was carried out at 3 stations of 100 m2 inside the citrus orchard studied. The floristic surveys were performed in the stations at different times (before and after each weeding). In the floristic inventory, 168 surveys were carried out and a total of 88 species were identified belonging to 71 genera and 30 botanical families. This adventitious flora was dominated by the Mediterranean ele ments (64%), the therophytes (51%) and dicotyledons (64%). Statistical elaboration of floristic data by means of multifactorial ANOVA revealed the existence of a significant spatial-temporal difference in the mean species richness between the stations (control vs. chemical and mechanical). In addition, the species richness before weeding tended to be higher than that after it. Weeding methods practised by crop growers need to be reconsidered. The benefits that weeds can provide should be considered as well as the damage caused by the different weeding techniques.