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The objectives of this paper were to review the literature on the responses of root systems to elevated CO # in intact, native grassland ecosystems, and to present the results from a 2-yr study of root production and mortality in an intact calcareous grassland in Switzerland. Previous work in intact native grassland systems has revealed that significant stimulation of the size of root systems (biomass, length density or root number) is not a universal response to elevated CO # . Of the 12 studies reviewed, seven showed little or no change in root-system size under elevated CO # , while five showed marked increases (average increase 38%). Insufficient data are available on the effects of elevated CO # on root production, mortality and life span to allow generalization about effects. The diversity of experimental techniques employed in these native grassland studies also makes generalization difficult. In the present study, root production and mortality were monitored in situ in a species-rich calcareous grassland community using minirhizotrons in order to test the hypothesis that an increase in these two measures would help explain the increase in net ecosystem CO # uptake (net ecosystem exchange) previously observed under elevated CO # at this site (600 vs 350 µl CO # l −" ; eight 1.2-m# experimental plots per CO # level using the screen-aided CO # control method). However, results from the first 2 yr showed no difference in overall root production or mortality in the top 18 cm of soil, where 80-90% of the roots occur. Elevated CO # was associated with an upward shift in root length density : under elevated CO # a greater proportion of roots were found in the upper 0-6-cm soil layer, and a lower proportion of roots in the lower 12-18 cm, than under ambient CO # . Elevated CO # was also associated with an increase in root survival probability (RSP ; e.g. for roots still alive 280 d after they were produced under ambient CO # , RSP l 0.30 ; elevated CO # , RSP l 0.56) and an increase (48%) in median root life span in the deepest (12-18 cm) soil layer. The factors driving changes in root distribution and longevity with depth under elevated CO # were not clear, but might have been related to increases in soil moisture under elevated CO # interacting with vertical patterns in soil temperatures. Thus extra CO # taken up in this grassland ecosystem during the growing season under elevated CO # could not be explained by changes in root production and mortality. However, C and nutrient cycling might be shifted closer to the soil surface, which could potentially have a substantial effect on the activities of soil heterotrophic organisms as CO # levels rise.

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Summary Rumex crispus and R. obtusifolius are among the most important perennial weeds in agriculture throughout the world. This literature survey revealed that the majority of studies on Rumex ecology, which were conducted under field conditions are of a descriptive nature, while experimental studies mainly report data derived under laboratory or greenhouse conditions. Areas on Rumex ecology which deserve more research include: historical development of Rumex infestations, field studies on seed and root ecology, population ecology, Rumex longevity, and impacts of global climate change on the performance of these species. Although biological, mechanical and cultural control methods were often effective in controlling Rumex populations, they were rarely successful enough to eradicate the weeds. As both species are considered to be indicators of agricultural mismanagement, there is a definite need for well‐replicated, full‐factorial, long‐term field experiments to assess the role of management factors most often stated to be responsible for Rumex infestation and distribution (e.g. high soil N and K levels, slurry and farmyard manure application, sward disturbance, cutting frequency, grazing management, ploughing, soil compaction). It is recommended that future research on non‐chemical Rumex control should focus more on the efficacy of combined applications of biological, mechanical and cultural control methods.

At the global scale, vineyards are usually managed intensively to optimize wine production without considering possible negative impacts on biodiversity and ecosystem services (ES) such as high soil erosion rates, degradation of soil fertility or contamination of groundwater. Winegrowers regulate competition for water and nutrients between the vines and inter‐row vegetation by tilling, mulching and/or herbicide application. Strategies for more sustainable viticulture recommend maintaining vegetation cover in inter‐rows, however, there is a lack of knowledge as to what extent this less intensive inter‐row management affects biodiversity and associated ES.We performed a hierarchical meta‐analysis to quantify the effects of extensive vineyard inter‐row vegetation management in comparison to more intensive management (like soil tillage or herbicide use) on biodiversity and ES from 74 studies covering four continents and 13 wine‐producing countries.Overall, extensive vegetation management increased above‐ and below‐ground biodiversity and ecosystem service provision by 20% in comparison to intensive management. Organic management together with management without herbicides showed a stronger positive effect on ES and biodiversity provision than inter‐row soil tillage.Soil loss parameters showed the largest positive response to inter‐row vegetation cover. The second highest positive response was observed for biodiversity variables, followed by carbon sequestration, pest control and soil fertility. We found no trade‐off between grape yield and quality vs. biodiversity or other ES. Synthesis and applications. Our meta‐analysis concludes that vegetation cover in inter‐rows contributes to biodiversity conservation and provides multiple ecosystem services. However, in drier climates grape yield might decrease without irrigation and careful vegetation management. Agri‐environmental policies should therefore focus on granting subsidies for the establishment of locally adapted diverse vegetation cover in vineyard inter‐rows. Future studies should focus on analysing the combined effects of local vineyard management and landscape composition and advance research in wine‐growing regions in Asia and in the southern hemisphere.

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Post transplant success after nursery stage is strongly influenced by plant morphology. Cultural practices strongly shape plant morphology, and substrate choice is one of the most determining factors. Peat is the most often used amendment in commercial potting substrates, involving the exploitation of non-renewable resources and the degradation of highly valuable peatland ecosystems and therefore alternative substrates are required. Here the feasibility of replacing peat by compost or vermicompost for the production of tomato plants in nurseries was investigated through the study of the effect of increasing proportions of these substrates (0%, 10%, 20%, 50%, 75% and 100%) in target plant growth and morphological features, indicators of adequate post-transplant growth and yield. Compost and vermicompost showed to be adequate substrates for tomato plant growth. Total replacement of peat by vermicompost was possible while doses of compost higher than 50% caused plant mortality. Low doses of compost (10 and 20%) and high doses of vermicompost produced significant increases in aerial and root biomass of the tomato plants. In addition these treatments improved significantly plant morphology (higher number of leaves and leaf area, and increased root volume and branching). The use of compost and vermicompost constitute an attractive alternative to the use of peat in plant nurseries due to the environmental benefits involved but also due to the observed improvement in plant quality.Additional key words: peat moss, plant nursery, soil-less substrate, Solanum lycopersicum L. Resumen Compost y vermicompost como componentes de sustratos artificiales de cultivo en viveros: efectos en el crecimiento y morfología del tomateTanto las prácticas de cultivo en los viveros como la elección del tipo de sustrato tienen una gran influencia sobre la morfología de las plántulas y por lo tanto en su adaptación post transplante. Aunque la turba es uno de los sustratos más utilizados en viveros, su uso conlleva la explotación de un recurso no renovable y la degradación de las turberas, por lo que se hace necesaria la búsqueda de sustratos alternativos que puedan reemplazarla total o parcialmente. En este trabajo se investigó la posibilidad de reemplazar la turba por compost o vermicompost en la producción de plántulas de tomate, mediante el estudio de los efectos de proporciones crecientes de estos sustratos (0%, 10%, 20%, 50%, 75% y 100%) en parámetros morfológicos y de crecimiento claves para la adaptación post transplante. Compost y vermicompost mostraron ser sustratos adecuados para el crecimiento de las plántulas. La sustitución total de la turba sólo fue posible con vermicompost mientras que las dosis de compost mayores que el 50% produjeron la mortalidad de las plántulas. Las dosis bajas de compost (10 y 20%) y altas de vermicompost, produjeron incrementos significativos en la biomasa aérea y radicular de las plantas. Además estas dosis mejoraron de forma significativa su morfología (número de hojas, superficie foliar, volume...

Herbicide use is increasing worldwide both in agriculture and private gardens. However, our knowledge of potential side-effects on non-target soil organisms, even on such eminent ones as earthworms, is still very scarce. In a greenhouse experiment, we assessed the impact of the most widely used glyphosate-based herbicide Roundup on two earthworm species with different feeding strategies. We demonstrate, that the surface casting activity of vertically burrowing earthworms (Lumbricus terrestris) almost ceased three weeks after herbicide application, while the activity of soil dwelling earthworms (Aporrectodea caliginosa) was not affected. Reproduction of the soil dwellers was reduced by 56% within three months after herbicide application. Herbicide application led to increased soil concentrations of nitrate by 1592% and phosphate by 127%, pointing to potential risks for nutrient leaching into streams, lakes, or groundwater aquifers. These sizeable herbicide-induced impacts on agroecosystems are particularly worrisome because these herbicides have been globally used for decades.