An ecological future for weed science to sustain crop production and the environment. A review

Abstract

Sustainable strategies for managing weeds are critical to meeting agriculture’s potential to feed the world’s population while conserving the ecosystems and biodiversity on which we depend. The dominant paradigm of weed management in developed countries is currently founded on the two principal tools of herbicides and tillage to remove weeds. However, evidence of negative environmental impacts from both tools is growing, and herbicide resistance is increasingly prevalent. These challenges emerge from a lack of attention to how weeds interact with and are regulated by the agroecosystem as a whole. Novel technological tools proposed for weed control, such as new herbicides, gene editing, and seed destructors, do not address these systemic challenges and thus are unlikely to provide truly sustainable solutions. Combining multiple tools and techniques in an Integrated Weed Management strategy is a step forward, but many integrated strategies still remain overly reliant on too few tools. In contrast, advances in weed ecology are revealing a wealth of options to manage weeds at the agroecosystem level that, rather than aiming to eradicate weeds, act to regulate populations to limit their negative impacts while conserving diversity. Here, we review the current state of knowledge in weed ecology and identify how this can be translated into practical weed management. The major points are the following: (1) the diversity and type of crops, management actions and limiting resources can be manipulated to limit weed competitiveness while promoting weed diversity; (2) in contrast to technological tools, ecological approaches to weed management tend to be synergistic with other agroecosystem functions; and (3) there are many existing practices compatible with this approach that could be integrated into current systems, alongside new options to explore. Overall, this review demonstrates that integrating systems-level ecological thinking into agronomic decision-making offers the best route to achieving sustainable weed management.

Combined effect of crop rotation and carabid beetles on weed dynamics in arable fields

“…Integrated weed management applied in conventional agricultural systems has always aimed at combining multiple approaches to increase the efficiency of weed management. However, the complexity and the level of integration of ecological processes regulating the density and controlling for weed outbreaks is often very limited (MacLaren et al, 2020; Petit et al, 2018). Because seeds in the seedbank are buried in the soil and remain invisible to farmers, it is challenging to explicitly accounted for in weed management plans.…”

“…Better integration of ecological understanding is urgent, not only to reduce the impact on the environment but also to increase its efficiency and secure long-term productivity of arable systems (Petit et al, 2018). To harness their full potential, integrated weed management approaches must adopt strategies that target different stages of the life cycle to contain their density above ground and their accumulation in the seedbank (MacLaren et al, 2020). By carefully designing crop rotations, farmers can influence weed demography by altering the degree of crop-weed competition, the timing of crop emergence, as well as the density and the height of the vegetation cover.…”

Impact of Organic Farming on Sustainable Agriculture System and Marketing Potential: A Review

“…[118] Complicated weed management is another drawback of organic farming but studies reveal that weed population density and biomass production may be noticeably control using the crop rotation and intercropping method. [119][120][121][122]…”

Spatial Distribution of Pollinating Butterflies in Yunnan Province, Southwest China with Resource Conservation Implications

“…When most farmlands belong to smaller households rather than industries, biodiversity in montane agroecosystems is better preserved than homogenous monocultures in intensive farms. In this way, butterflies can be sheltered by higher biodiversity in agroecosystems such as unmanaged ridges and hedges [101][102][103][104][105][106]. This is more effective for widespread species than those narrow-ranged ones.…”