Trajectories of weed communities explained by traits associated with species’ response to management practices

Environmental factors including management practices as correlates of weed community composition in spring seeded crops

Canadian Journal of Botany ◽

10.1139/b92-240 ◽

1992 ◽

Vol 70 (10) ◽

pp. 1931-1939 ◽

Cited By ~ 58

Author(s):

M. R. T. Dale ◽

A. G. Thomas ◽

E. A. John

Keyword(s):

Community Composition ◽

Correspondence Analysis ◽

Canonical Correspondence Analysis ◽

Environmental Variables ◽

Management Practices ◽

Geographic Region ◽

Climatic Conditions ◽

Weed Species ◽

Weed Communities ◽

Seed Crops

The relationship between the weed communities and environmental variables such as soil, crop, and management was investigated in two provinces of Canada. The frequencies of weed species were recorded in cereal and oilseed fields in Saskatchewan (2244 fields over 4 years) and Manitoba (864 fields over 3 years), Canada. Information on some of the physical characteristics of the fields and on the management practices imposed on them was also collected, in part by questionnaire. The two kinds of data were ordinated together using canonical correspondence analysis to assess the relationships between the species and the environmental variables. In the Saskatchewan data, there was a clear and consistent separation of the species into groups along an axis correlated with soil zone and the associated climatic gradient. In the Manitoba data, the same groups of species did not separate as clearly or as consistently, although geographic region was a major determinant of the weed communities. The greater variability may be due to the fact that the gradient of soil types is much more restricted in Manitoba and not as closely correlated with climatic conditions. In both provinces, culture practices were less important as correlates of the weed community composition than soil type or, to a certain extent, the previous crop. Key words: canonical correspondence analysis, cereal crops, oil seed crops.

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Generating a Visual Effects Analysis for the Deepwater Horizon Endangered Species Act Biological Assessment

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2014-1-300294.1 ◽

2014 ◽

Vol 2014 (1) ◽

pp. 300294

Author(s):

Travis Coley ◽

Jessica Odell ◽

Doug Anderson

Keyword(s):

Endangered Species ◽

Best Management Practices ◽

Management Practices ◽

Endangered Species Act ◽

Deepwater Horizon ◽

The United States ◽

Biological Assessment ◽

Incident Command ◽

Species Response ◽

Species Responses

Although species expertise, professional judgment, and scientific literature pave the way for making determinations of effects, the vastness of the Deepwater Horizon Incident response inspired a systematic approach. The United States Coast Guard (USCG) Endangered Species Act Biological Assessment (BA) for this response began with the development of ecological models for each of the listed species potentially affected by the response. These models are tabular and connect individual strands of logic, referred to as effects pathways, which relate a potential cleanup activity to the anticipated species response. Effects pathways cannot be used alone, as they are inherently isolated and independent of any response action data. To bring the effects pathways into the context of the actual cleanup effort, a forensic geographically aware action record was generated. This record was primarily built using prescriptions for cleanup, known as Shoreline Cleanup Recommendations (STRs), Incident Command System (ICS) Forms, and Best Management Practices (BMP) Checklists. The combination of effects pathways and the action record was completed using table joining techniques. The anticipated species responses to actions were then used to create a series of heat maps. These show the accumulation of species responses along the landscape based on temporal components of activities, such as frequency and intensity. These maps provide a visual means of consuming the vast occurrences of the response to facilitate the effects analysis of the BA.

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Relative importance of region, seasonality and weed management practices effects on the functional structure of weed communities in French vineyards

10.1101/2021.10.26.465884 ◽

2021 ◽

Author(s):

Marie-Charlotte Bopp ◽

Elena Kazakou ◽

Aurelie Metay ◽

Guillaume Fried

Keyword(s):

Weed Management ◽

Management Practices ◽

Environmental Gradients ◽

Cropping Systems ◽

Seed Mass ◽

Soil Disturbance ◽

Lateral Spread ◽

Maximum Height ◽

Weed Communities ◽

Mechanical Disturbance

Winegrowers have diversified their weed management practices over the last two decades changing the structure and the composition of weed communities. Complementary to taxonomic studies, trait-based approaches are promising ways for a better understanding of weed communities responses to environmental and agronomic filters. In the present study, the impacts of climate, soil characteristics, seasons and weed management practices (chemical weeding, tillage and mowing) were assessed on weed communities from 46 plots in three French wine-growing regions (Champagne, Languedoc and Rhone valley). These agro-environmental gradients structuring weed communities according to their combinations of traits were highlighted using multivariate analysis (RLQ). The impacts of these filters on Community Weighted Means (CWM) and Community Weighted Variance (CWV) of weed communities were analysed using mixed and null modelling. Our results showed that spatio-temporal and weed management practices variables explained from 13% to 48% of the total variance of CWM (specific leaf area, maximum height, seed mass, flowering onset and duration and lateral spread). Region, seasonality and management practices explained 53%, 28% and 19% of CWM marginal variance, respectively. Weed management impacted CWM and CWV through two main gradients: (i) a soil disturbance gradient with high mechanical disturbance of soil in tilled plots and low mechanical disturbance in chemically weeded plots and (ii) a vegetation cover gradient with high vegetation abundance in mowed plots compared to more bare soils in tilled and chemically weeded plots. In Languedoc, chemical weeding filtered weed communities with ruderal strategy trait values (low seed mass, small-stature) while mowed communities were more competitive (higher seed mass, higher stature and lower SLA). In Languedoc and Champagne, tillage favoured communities with high seed mass that increases the viability of buried seeds and high lateral spread values associated to the ability to resprout after tillage. This study demonstrated that trait-based approaches can be successfully applied to perennial cropping systems such as vineyards, in order to understand community assembly to better guide weed management practices.

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Weed communities associated with arable Saskatchewan farm management systems

Canadian Journal of Plant Science ◽

10.4141/p99-039 ◽

2000 ◽

Vol 80 (1) ◽

pp. 177-185 ◽

Cited By ~ 26

Author(s):

J. Y. Leeson ◽

J. W. Sheard ◽

A. G. Thomas

Keyword(s):

Life History ◽

Correspondence Analysis ◽

Canonical Correspondence Analysis ◽

Management System ◽

Management Practices ◽

Farming System ◽

Management Systems ◽

Weed Communities ◽

History Of ◽

The Impact

The objective of this study was to determine the impact of a range of management systems on weed communities in cropped fields on farms in Saskatchewan. Farms (n = 28) with management systems defined by a combination of different cropping histories and chemical input levels were selected. Fields were surveyed on each farm in 1995, 1996, and 1997 after any post-emergent weed control to ensure that their weed communities reflected the impact of all agronomic management practices typical of the management system. Canonical correspondence analysis was used to determine whether weed communities were significantly correlated with management system after removal of variance due to ecoregion and year. The largest difference in weed communities attributable to farming system was between the systems with annual cropping histories and those that included perennials in the cropping history. Thus, the life history of the weeds reflected the life history of the crops. Herbicide use was correlated with the next largest difference between systems. A significant association between weed communities and different management systems indicates that weed species are being selected for by these systems. If such selection pressure continues, these species may become a threat to the system's sustainability. Key words: Weed communities, chemical input level, cropping history, canonical correspondence analysis, correspondence analysis, farming system

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Weed Functional Diversity as Affected by Agroecological Service Crops and No-Till in a Mediterranean Organic Vegetable System

Plants ◽

10.3390/plants9060689 ◽

2020 ◽

Vol 9 (6) ◽

pp. 689

Author(s):

Corrado Ciaccia ◽

Laura Armengot Martinez ◽

Elena Testani ◽

Fabrizio Leteo ◽

Gabriele Campanelli ◽

...

Keyword(s):

Functional Traits ◽

Management Practices ◽

Weed Suppression ◽

Soil Tillage ◽

Weed Communities ◽

Long Run ◽

Before And After ◽

Long Term Experiment ◽

Flowering Onset ◽

Selection Of

This paper explores the effect of agroecological service crops (ASCs), i.e., crops included in the crop rotation for their ecosystem services, terminated with an in-line tillage roller crimper (ILRC) on weed community composition and their functional traits in comparison to a tilled control without ASC. A two-year study was performed in a long-term experiment with vegetables under organic management. Four different cereal crops were introduced as ASCs. Weed abundance and richness and the functional traits were assessed at three different stages, i.e., before and after ASC termination and before harvest of the following crop, melon. All the ASCs showed strong weed suppression, with few differences between the cereals tested. Weed communities with ASCs had later flowering onset and wider flowering span compared to the control, which positively affects weed dispersal and attraction of beneficial insects. However, weed communities with ASCs had higher values for traits related to competition (specific leaf area, seed weight and more perennials). A trade-off between weed suppression and selection of more competitive weed communities by the introduction of ASCs managed with the ILRC should be evaluated in the long-run. The use of the ILRC alternating with other soil management practices seems the more effective strategy to benefit from the minimal soil tillage while avoiding the selection of disservice-related traits in the weed community.

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Management practices influence the competitive potential of weed communities and their value to biodiversity in South African vineyards

Weed Research ◽

10.1111/wre.12347 ◽

2019 ◽

Vol 59 (2) ◽

pp. 93-106 ◽

Cited By ~ 3

Author(s):

C MacLaren ◽

J Bennett ◽

K Dehnen-Schmutz

Keyword(s):

South African ◽

Management Practices ◽

Weed Communities

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The dynamics of experimental arable weed communities under different management practices

Journal of Vegetation Science ◽

10.2307/3236458 ◽

1996 ◽

Vol 7 (6) ◽

pp. 799-808 ◽

Cited By ~ 52

Author(s):

M. McCloskey ◽

L.G. Firbank ◽

A.R. Watkinson ◽

D.J. Webb

Keyword(s):

Management Practices ◽

Weed Communities ◽

Arable Weed

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Weed Management in Asian Vegetable Cropping Systems

Weed Science ◽

10.1017/s004317450005565x ◽

1980 ◽

Vol 28 (4) ◽

pp. 445-451 ◽

Cited By ~ 1

Author(s):

R. D. William ◽

M. Y. Chiang

Keyword(s):

Weed Management ◽

Crop Production ◽

Management Practices ◽

Climatic Factors ◽

Cropping Systems ◽

Management Strategies ◽

Cropping System ◽

Competitive Balance ◽

Weed Communities ◽

Control Technologies

In tropical and subtemperate regions of the world, farmers plant vegetables and other crops in a vast array of cropping systems that often involve more than one crop being grown on the same parcel of land in a year. Weed communities within each cropping system shift depending on physical and climatic factors and the specific crop and weed management practices employed. Modern weed management strategies involve combinations of crop production practices and specific weed control technologies intended to reduce weed competition, thereby shifting the competitive balance in favor of the crop. Weed research and, training efforts, therefore, must focus on the entire cropping system with emphasis on year-round and multi-year management of weed communities.

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Timing of tillage is an important filter on the assembly of weed communities

Weed Science ◽

10.1614/ws-05-177r1.1 ◽

2006 ◽

Vol 54 (4) ◽

pp. 705-712 ◽

Cited By ~ 45

Author(s):

Richard G. Smith

Keyword(s):

Weed Management ◽

Management Practices ◽

Light Availability ◽

Species Traits ◽

Weed Communities ◽

Ecological Principles ◽

Arable Weed ◽

C3 Grasses ◽

Soil Disturbances ◽

Resource Levels

A trait-based community assembly approach to weed management may enhance our understanding of how weed communities respond to specific management practices and increase the utility of weed management based on ecological principles. Therefore, identifying management practices that operate as assembly filters and the species traits upon which they act is an important first step in developing a more predictive weed science. Here, I report results from a 3-yr investigation of the effects of timing of annual tillage (spring vs. fall) on the annual assembly of arable weed communities. The timing of tillage had consistent and dramatic effects on the composition of weed communities; spring tillage led to weed communities dominated by early emerging spring annual forbs and C4 grasses, and fall tillage led to communities dominated by later-emerging forbs and C3 grasses. Traits determining a species' susceptibility to tillage time likely include germination syndrome and life cycle, both of which influence how species respond to changes in soil resource levels and light availability driven by seasonal disturbance regime. Manipulating the timing of tillage and other major soil disturbances may therefore be an important tool for managers interested in influencing community composition or targeting species with similar germination and life-history traits.

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