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Cirsium arvense (L.) Scop. is one of the most problematic perennial weeds in European countries, causing notable yield losses in both conventional and organic arable cropping systems. C. arvense control is essential because its infestation spreads rapidly and has negative impacts for several years due to its biological characteristics. Herbicidal treatments are the main control methods used in conventional input-based systems, but they are not always more effective than cultural practices. However, the cultural practices currently employed in arable cropping systems are often expensive and time-consuming. To guarantee the efficiency of these control practices, knowledge of C. arvense biology is essential. This review synthesizes the key points from the previous literature on C. arvense biology that can be mobilized to this end and analyzes the literature on different strategies of C. arvense control without herbicides. These strategies are (1) limitation of C. arvense dispersal, (2) weakening of root reserves, (3) extraction of roots, (4) competition with cultivated species, and (5) physical destruction. There is also a review of reported experiences using these strategies for C. arvense control, and relevant information is presented on associated biological processes to optimize the efficacy of each practice. The benefits and drawbacks of these strategies for C. arvense control are also emphasized, as well as the possibility of combining them in cropping systems, even though some knowledge gaps remain. This review confirms that one individual practice, implemented in 1 year only, is not sufficient to provide satisfactory, long-term control of C. arvense; therefore, further studies on combinations of control strategies and processes are required. There is a particular lack of knowledge about the duration of the effect of C. arvense control strategies. [ABSTRACT FROM AUTHOR]

The delivery of multiple ecosystem services from intensively managed cropping systems remains challenging mainly because increases in crop yields are rarely associated with greater soil carbon (C) sequestration or efficient ecosystem nitrogen (N) cycling. The sustainability of intensive cropping systems depends on trade-offs between multiple ecosystem services but experimental evidence from long-term field studies remains limited. The common expectation is that highly productive agroecosystems will be associated with lower soil C and reduced nutrient use efficiency. Here we use data spanning 30 years of a long-term field experiment established in 1985 near Lodi in Northern Italy where four arable systems (i.e., three crop rotations and a grain maize monoculture) and a no-till permanent meadow were all compared across two levels of agronomic inputs. We asked how (i) soil C stocks, (ii) fertilizer N-use efficiency, (iii) productivity, (iv) crude protein, and (v) feed units for lactation might differ across the five traditional cropping systems. We found that soil C sequestration, N-use efficiency, and crude protein production were all significantly higher in the no-till permanent meadow, which was however associated with lower dry matter yields and reduced feed units for lactation when compared with the arable systems. These findings suggest that converting arable soil into no-till permanent meadow is a win-lose solution. The most productive annual rotation (silage maize + Italian ryegrass) offers a complementary win-lose solution whereby high yields and feed units for lactation can be obtained from a smaller cropland area. The other cropping systems are less productive and provide little (or none) soil C storage benefits. Our study is one of the first to show clear trade-offs between multiple ecosystem services and to demonstrate that high fertilization rates might be only justified when the management goal is to spare land for less intensive uses such as permanent meadow. [ABSTRACT FROM AUTHOR]

This study has reviewed 66 long-term experimental comparisons on Soil Organic Carbon (SOC) and tillage systems in Mediterranean arable crops (from 15 sites located in Greece, Italy, Morocco and Spain), with the aim to identify the biophysical and agronomic variables most associated with C sequestration rate. Data were organized in a dataset containing basic environmental descriptors (elevation, temperature, rainfall), information on soil tillage system (conventional, minimum, no-tillage), soil attributes (pH, particle size distribution and texture), crop rotation, fertilization, time length of the experiment, initial and final SOC stocks. The collected information were analyzed using a data mining approach including Spearman non-parametric correlations, Principal Component Analysis (PCA), hierarchical clustering and step-wise multiple regression. Tillage, crop rotation, and fertilization were the most significant factors affecting C sequestration rate. Non-parametric correlations reported negative coefficients for initial SOC stock, length of the experiment, mineral fertilization, tillage and production system. C sequestration rate increased significantly under no-tillage. Hierarchical clustering indicates that geographical proximity reflects similarity in biophysical conditions and agronomic practices. PCA outlined a positive correlation of SOC with soil depth, elevation and sites located in Spain and a negative correlation with mean air temperature, mineral fertilization, irrigation, experiment's length and sites located in Greece. C sequestration rate was positively associated with mean air temperature. Finally, a step-wise multiple regression indicated that C sequestration rate increased in sites exposed to colder climate conditions and under no-tillage. [ABSTRACT FROM AUTHOR]

An ideal agricultural system should both maximize food production and minimize undesirable effects on the environment. The long-term Apelsvoll cropping system experiment, located in southeast Norway, was used in this study, to compare yields, major N flows (in particular measured leaching/runoff losses) and the N loss-to-food production ratios (LFP-ratios) in six different cropping systems over a 4-year period. The experiment included three systems with cash-cropping (CA1: conventional arable farming; CA2: arable farming practice with environmentally sound management; OA: organic arable farming with 25% of the area as green manure, and three systems with both arable and fodder crops, representing mixed dairy production (CM: conventional farming practice with 50% grass–clover ley; OM1: organic farming with 50% grass–clover ley; OM2: organic farming with 75% grass–clover ley). The forage production was assumed to be used for milk and meat production, in amounts calculated on the basis of available feed and estimated requirements for dairy cattle. All farm produce (cereals, potatoes, milk and meat) was converted into metabolizable energy for human consumption. Organic cropping gave significantly lower yields than conventional cropping, for both arable and mixed dairy systems, most likely due to sub-optimal plant nutrition and the lack of plant protection in the organic systems. The average net energy production in CA1 and CA2 was 2.4–5.3 times greater than that in the other systems, which illustrates the energy costs of taking 25% of the area out of food production to produce green manure (OA) and the energy cost of including an extra trophic level in the nutrient chain (CM, OM1 and OM2). Only CA2 and CM appeared to have a balanced N budget, whereas the other systems all had N deficits, in particular CA1 and OA. The total N losses to drainage were largest from CA1, but not significantly larger than those from OA, which had the largest N runoff of the systems, most likely due to the green manure in its rotation. The conventional system with environmentally sound management (CA2) had the lowest LFP-ratios overall. Among the arable cropping systems, the organic system with 25% green manure (OA) had the highest LFP-ratios. The mixed dairy systems had generally higher LFP-ratios than the arable systems. Including leaching/runoff N losses in the LFP-ratio, CA1, CA2, OA, CM, OM1 and OM2 appeared to lose 0.6, 0.4, 1.1, 0.9, 1.2 and 1.1kg N, respectively, per GJ of produced metabolizable energy for human consumption. [Copyright &y& Elsevier]