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Humulus lupulus is a dioecious twining herb, with an outstanding vertical development capacity. Hop plants are usually grown on trellises up to 4.5 to 6.0 m high, whose management requires intense use of water, fertilizers, pesticides, and labor. In semiarid Mediterranean areas, where native resources are often scarce, the adoption of low-trellis farming systems could be a sustainable option for hop cultivation. With the aim of evaluating hop suitability to low-trellis cultivation in a Mediter)ranean environment, in 2018 and 2019 three traditional hop genotypes (‘Cascade’, ‘Chinook’, and ‘Nugget’) were grown, and their development rate was evaluated and put in relation with the plants’ cone, root, and biomass yield. Moreover, organic (fragmented pine bark) and synthetic [black polyethylene (PE) plastic film] mulches were applied on the same cultivars, and both epigeal and hypogeal development were evaluated. The results showed that the faster the growth in the first two phases of plant elongation (up to 50% of the height of the upper wire), the lower the yield in both cones and total epigeal biomass. A fast growth rate was instead associated with a higher hypogeal biomass production. Mulching was able to significantly affect the hypogeal biomass, specifically for cv. Cascade, where the use of synthetic mulching allowed significant root biomass increases. The analysis of the results obtained showed that hop’s suitability to a low-trellis farming system is highly variable among varieties in the semiarid Mediterranean environment. [ABSTRACT FROM AUTHOR]

Northern oceans are in a state of rapid transition. Still, our knowledge of the likely effects of climate change and ocean acidification on key species in the food web, functionally important habitats and the structure of Arctic and sub-Arctic ecosystems is limited and based mainly on short-term laboratory studies on single species. This review discusses how tropical and temperate natural analogues of carbonate chemistry drivers, such as CO2 vents, have been used to further our knowledge of the sensitivity of biological systems to predicted climate change, and thus assess the capacity of different species to show long-term acclimation and adaptation to elevated levels of p CO2. Natural analogues have also provided the means to scale-up from single-species responses to community and ecosystem level responses. However, to date the application of such approaches is limited in high latitude systems. A range of Arctic and sub-Arctic sites, including CO2 vents, methane cold seeps, estuaries, up-welling areas, and polar fronts, that encompass gradients of pH, carbonate saturation state, and alkalinity, are suggested for future high latitude, in-situ ocean acidification research. It is recommended that combinations of monitoring of the chemical oceanography, observational, and experimental (in situ and laboratory) studies of organisms around these natural analogues be used to attain better predictions of the impacts of ocean acidification and climate change on high latitude species and ecosystems. [ABSTRACT FROM AUTHOR]