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In the past, the floristic diversity of arable fields has been described in terms of species diversity (SD) and their degree of coverage (C), but never in combination with the recording of the actually flowered species (FS) and their flowering intensity (FI) to striking differences in the cultivation methods on arable land. In relation to SD and C, however, FS and FI may provide important additional information on the functional biodiversity of fields. The aim was therefore to investigate the effects of (a) conventional, (b) organic, and (c) smallholder (never application of herbicides) on the floristic diversity. Using a region in Germany, we investigated SD, C, FS, and FI synchronously in (a), (b), and (c), by 356 vegetation surveys (5 × 5 m plots) conducted in spring and summer in 2019 in winter cereals. Statistical tests were used to analyze the differences between (a), (b), and (c). The medians were used to compare the floristic diversity of (a), (b), and (c) and finally relationships of FS and FI to SD were analyzed in relation to the cultivation methods. Significant differences in SD, C, FS, and FI were found between the (a), (b), and (c) in spring and summer characterized by sharp declines from (c) to (b) to (a). A drastic reduction in floristic diversity from (c) 100 to (b) 52 to (a) 3 was determined. Plants in flower (FS, FI) were very poorly in (a), moderately well to well in (b), and well to very well represented in (c). (C) to (a) was characterized by a sharp decline and from (a) to (b) by sharp increase in floristic diversity. With current acreage proportions of (a) in mind, this would affect, about one third of land area in Germany, associated with a drastic reduction in functional biodiversity for insects., Significant differences in species diversity (SD), coverage (C), flowering species (FS) and flowering intensity (FI) were found between the three fundamentally different cultivation methods of arable fields: (a) conventional farmland; (b) organic farmland; and (c) smallholder farmland that had never been treated with pesticides. These were characterised by sharp declines in SD, C, FS and FI from (c) to (b) to (a), summarised in a relation of the floristic diversity from 100 to 52 to 3 associated with a drastic reduction in functional biodiversity for insects.

1) Carabid beetles are major predators in agro-ecosystems. The composition of their communities within crop environments governs the pest control services they provide. An understudied aspect is the distribution of predacious carabid larvae in the soil. 2) We used novel subterranean trapping with standard pitfall trapping, within a multi-crop rotation experiment, to assess the responses of above- and below-ground carabid communities to management practices 3) Crop and trap type significantly affected pooled carabid abundance with an interaction of the two, the highest numbers of carabids were caught in subterranean traps in barley under sown with grass. 4) Trap type accounted for the most variance observed in carabid community composition, followed by crop. 5) Tillage responses were only apparent at the species level for three of the eight species modelled. 6) Responses to crop type varied by species. Most species had higher abundance in under-sown barley, than grass, wheat and barley. Crop differences were greater in the subterranean trap data. For predaceous larvae standard pitfalls showed lowest abundances in under-sown barley, yet subterranean traps revealed actual abundances to be highest in this crop. 7) Comprehensive estimation of ecosystem services should incorporate both above- and below ground community appraisal, towards appropriate management.

While climate change mainly applies to global warming and subsequent drought periods, freezing periods also are changing and may trigger genetic adaptation. However, there are few prospective, experimental demonstrations. This paper investigates how effectively genetic frost-resistant variants can respond differently to frost periods, especially in farmers’ fields where various other selection pressures occur. An experiment using Avena fatua variants was set up in the field over 8 years of winter crop rotation. The frequency of each variant identified by their leaf isozymes was estimated every year. Six years were necessary to observe a weak trend towards an increased frequency of the frost-resistant phenotype, while the other variants had apparent erratic behaviour. Selection of the frost-resistant variant was challenged by irregular low temperature selection pressure, differential dormancy, germination and seed production, and possibly herbicide sensitivity that mitigated the expression of the selection response. This experiment shows how plant polymorphism and farmers’ practices that superimpose habitat unpredictability diversify possible responses to selection pressures and delay adaptation. However, if climate change brings both higher mean temperatures and extreme values, changes of apparent plant phenology could happen for weeds species displaying the appropriate genetic variability within the time-frame of farmers’ career, thus necessitating correlative adaptation of farming practices.

Fayoum region is the most fertile agricultural land in Egypt and one of the oldest agricultural city in the world. The present study aimed to determine its weed flora composition and its distribution through different habitats. Results recorded 175 species of vascular plants belonging to 124 genera and 35 families distributed in eight habitats. The richest families were Poaceae, Asteraceae (Compositae) and Fabaceae (Leguminoseae), while genera with the highest number of species were Euphorbia, Amaranthus and Cyperus. Cynodon dactylon and Alhagi graecorum were the present species, recorded at all habitats. Old cultivated lands recorded the highest species number followed by orchard habitats, on the contrast road side and wasteland habitats recorded the lowest species numbers. Therophytes were the dominant life form, while Phanerophytes were the smallest group in this study, 5%. The highest Jaccard similarity index was recorded between healthy land and orchard habitats, which supported also by ward classification. RESUMO: A região de Faium é a área agrícola mais fértil do Egito e uma das mais antigas cidades agrícolas do mundo. O presente estudo teve como objetivo determinar a composição da flora de plantas daninhas e sua distribuição através de diferentes habitats. Os resultados registraram 175 espécies de plantas vasculares pertencentes a 124 gêneros e 35 famílias, distribuídos em oito habitats. As famílias mais ricas foram Poaceae, Asteraceae (Compositae) e Fabaceae (Leguminoseae), enquanto os gêneros com maior número de espécies foram Euphorbia, Amaranthus e Cyperus. Cynodon dactylon e Alhagi graecorum foram as espécies presentes, registradas em todos os habitats. As antigas terras cultivadas registraram o maior número de espécies, seguidas dos habitats com pomares, ao contrário das margens de estradas e dos habitats de terras baixas, que registraram o menor número. Os terófitos foram a forma de vida dominante, e os fanerófitos foram o menor grupo neste estudo (5%). O maior índice de similaridade de Jaccard foi registrado entre as terras saudáveis e o habitat com pomares, o que também foi confirmado pelo método de Ward.

Question How does the conservation (rarity) value of arable weed communities differ along intensification gradients? Which functional traits best distinguish the weed communities of more and less extensively managed fields? Can the same traits predict the rarity of individual weed species? Location Hungary. Methods Using relevé data from 60 cereal and 70 stubble fields, together with weed trait data, we characterized community responses to arable intensification using functional trait analyses based on trait‐convergence and trait‐divergence assembly patterns. We also examined how well the broad‐scale rarity status of species predicts their occurrence along intensification gradients, and how it maps onto our functional classifications describing intensification responses. Results The response of weeds to intensification in cereal fields was best described by a functional classification based on species' flowering duration, maximum height and seed weight: weeds of extensively managed fields have short flowering seasons (2–5 mo) and particularly large or small seeds. The highest proportions of rare species also happen to be found in these groups. The rarest weeds among these species tend to be late‐winter and early‐summer annuals, while the rare species of stubble fields tend to be broad‐leaved with low nitrogen requirements, small seeds and short height. Stubble fields showed a decline in weed cover with increasing application of fertilizer and distance from the field edge, but we could detect no strong associations of management factors with trait composition, perhaps because the intensification gradient across these fields was shorter. Conclusions Many rare Hungarian weeds are associated with traditional extensive farming practices. They are particularly characterized by short, midsummer flowering periods and by preference for low nitrogen levels, but a range of trait syndromes must be considered to understand their ecology and conservation. Analyses based on trait‐divergence patterns, rather than trait‐convergence patterns, provide better insights into the functional composition of weed communities, emphasizing the importance of disruptive filters in weed community assembly and the need for improved methods to detect such effects., Weed floras of extensively‐managed cereal fields in western Hungary, compared to nearby intensive ones, were biased towards species with short flowering periods, particularly large or small seeds and species listed as nationally rare or declining. Compared to other species, cereal and stubble weeds listed as rare or declining tended to be broad‐leaved late winter annuals, shorter, smaller‐seeded and less nitrophilous.

Floristic research on segetal communities was carried out in 2000 on arable fields in the Skierbieszów Landscape Park and its protected zone. Three communities of segetal weeds in cereal crops, and two communities of segetal weeds in root crops were separated in the arable fields of the Skierbieszów Landscape Park. The community Vicietum tetraspermae typicum commonly occurred in cereal crops on brown soils developed from loess soils. The community Echinochloo-Setarietum, which belongs to root crops, was noted in the same habitat. The greatest richness of species was found in Consolido-Brometum and Lamio Veronicetum politae, with the average of 25 species in one record. Both communities were abundant in rare segetal species which are considered to be endangered in our country: Adonis aestivalis, Euphorbia exigua, Lathyrus tuberosus, Muscari comosum, Thlaspi perfoliatum, Veronica polita, Agrostemma githago.

International audience; Landscape ecology has highlighted the role of the surrounding landscape in structuring arthropod communities at a given place. Previous studies have confirmed that non-crop habitats in agricultural landscapes increase the abundance and diversity of natural enemies in crop fields, which can generate a positive impact on pest control. However, landscape structure may differentially affect generalist predator communities within a year. Our knowledge about how such intra-annual variation affects the biological control of pests is still scarce. In this study, we surveyed predator carabid and spider assemblages and estimated biological control potential using experimentally added aphids in 21 winter wheat fields from mid-March until harvest. We investigated whether landscape structure differentially affected predator activity density, species richness and species composition across months, as well as how the relationship between biological control potential and landscape structure changed over time. We also investigated whether different time steps (15-day sampling period vs. whole sampling season) influenced the detection and significance of landscape effects, Spider assemblages benefit from tine-grained landscapes in spring, but this effect disappeared later in summer, For carabids, species richness was the only biodiversity measure related to grain size, and the relationship was strongest when considering the whole sampling season, No relationship was found between landscape structure and biological control potential. Our study showed that the influence of landscape structure can be inconsistent across taxa, biodiversity measures and time. The results demonstrate the importance of time steps and seasonality in the relationship between landscape structure and biodiversity.

Multivariate analysis of data obtained from 184 cereal and stubble fields in low-input agricultural systems located in western Hungary was undertaken in order to asses environmental factors affecting weed species composition. For each variable, the gross and net effect on weed species composition was calculated. All variables considered in this study had a significant effect on weed species composition and explained 26.99% of the total variation. Most variation in species composition was explained by the aspect (cereal vs. stubble), followed by soil pH, mean annual precipitation, soil texture, mean annual temperature, and altitude. Separating the cereals and stubbles soil pH became the most important factor. Our results suggest that during the long vegetation period, cereal weed communities dominated by winter annuals are replaced by stubble-field weed communities dominated by summer annuals. This seasonal change may also have the same important effect on weed species composition as crop types.

Techniques such as rewetting, topsoil removal, diaspore transfer or combinations of these are increasingly applied in fen meadow and flood meadow restoration in Western Europe. In this paper, we present a quantitative assessment of the effectiveness of the commonly used meadow restoration methods. We use the change in 'saturation index' to evaluate the degree of success. The index reflects the completeness of restored communities in comparison to regional target communities. Meadow restoration has limited success in most cases, with an average increase in species richness below 10% of the regional species pool. Restoration success was partly determinated by the starting situation. The more species-rich the starting situation, the higher the saturation index after restoration but, at the same time, the smaller the increase in the number of target species due to restoration. Top soil removal and diaspore transfer were found to contribute most to restoration success. A combination of top soil removal and diaspore transfer and a combination of all three techniques appeared to be the most effective measure and resulted in an increase in the saturation index of up to 16%. Rewetting alone had no measurable effect on restoration success.

Species distribution models (SDM) are increasingly used to understand the factors that regulate variation in biodiversity patterns and to help plan conservation strategies. However, these models are rarely validated with independently collected data and it is unclear whether SDM performance is maintained across distinct habitats and for species with different functional traits. Highly mobile species, such as bees, can be particularly challenging to model. Here, we use independent sets of occurrence data collected systematically in several agricultural habitats to test how the predictive performance of SDMs for wild bee species depends on species traits, habitat type, and sampling technique. We used a species distribution modeling approach parametrized for the Netherlands, with presence records from 1990 to 2010 for 193 Dutch wild bees. For each species, we built a Maxent model based on 13 climate and landscape variables. We tested the predictive performance of the SDMs with independent datasets collected from orchards and arable fields across the Netherlands from 2010 to 2013, using transect surveys or pan traps. Model predictive performance depended on species traits and habitat type. Occurrence of bee species specialized in habitat and diet was better predicted than generalist bees. Predictions of habitat suitability were also more precise for habitats that are temporally more stable (orchards) than for habitats that suffer regular alterations (arable), particularly for small, solitary bees. As a conservation tool, SDMs are best suited to modeling rarer, specialist species than more generalist and will work best in long-term stable habitats. The variability of complex, short-term habitats is difficult to capture in such models and historical land use generally has low thematic resolution. To improve SDMs' usefulness, models require explanatory variables and collection data that include detailed landscape characteristics, for example, variability of crops and flower availability. Additionally, testing SDMs with field surveys should involve multiple collection techniques., info:eu-repo/semantics/published

The presence of earthworms in relation to clay soil structure problems in arable fields in the Flevopolders (the Netherlands) was studied. Recently, farmers in this area have had difficulty in harvesting potatoes in predominantly wet years. After a dry period, soil particles in the top layer of the potato ridges form a platy structure and are difficult to sieve. Locally, this resulted in many clods, and sometimes harvesting proved impossible. In the field, significantly more earthworms (mainly Aporrectodea caliginosa and A. rosea) were observed in the problem parts than in the non-problem parts. A macrocosm study showed significantly more settlement and soil stickiness and an increasing number of large clods caused by greater numbers of A. caliginosa. The results of this study reveal earthworms to be the main factor affecting the state of the soil and causing the harvesting problems.