Introduced ungulates can alter understory structure and composition posing a serious threat to forest biodiversity. Yet how large-herbivore impacts in forested regions vary along major environmental gradients remains little explored. If ungulate effects shift with habitat conditions, then management could be tailored to protect most vulnerable forests. We tested the hypothesis that the extent of livestock impact on understory vegetation increases with habitat moisture across Nothofagus dombeyi forests in Nahuel Huapi National Park, NW Patagonia, Argentina. Understory composition and species diversity were compared for paired sites (N = 5), which were historically used by cattle or remained free of livestock for more than 50 yr, and were located along a regional precipitation gradient (1500-2800 mm/yr). Long-term cattle presence reduced the cover of sub-canopy trees, shrubs and bamboo by 57-83%, and increased the relative cover of ground-layer herbs, regardless of habitat moisture. Livestock effects on species composition increased towards the wettest forests, which contained more species exclusive to either browsed or unbrowsed sites. Livestock presence increased species richness (a diversity) and within-site heterogeneity (b diversity) in some locations, but mostly reduced species evenness (30%) throughout the moisture gradient. Species turnover at the gradient scale was lower across browsed sites than for livestock-free sites. Our results indicate that the historical presence of domestic cattle induced region-wide changes in understory communities, highlighting the vulnerable nature of the local flora to ungulate disturbance. The greater impact of livestock browsing on the species composition of wetter forests was consistent with the role of plant growth-defence trade-offs along resource gradients. We suggest that the erosion of understory vegetation attributed to domestic herbivores in Patagonian beech forests can be mitigated by adjusting current animal stocks, while moister forests should be given the highest conservation priority.

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We wanted to understand how the competitive scientific system affected researchers in Argentina, whose budget to finance science is noticeably lower than in other countries and historically unstable. The objective was to identify factors that influence scientific vocation, main publication strategies and time-management tactics. A structured survey was designed and circulated online for 6 months (2018/2019). The 684 valid responses were separated per academic stage: PhD students (41%), postdoc fellows (21%) and senior researchers (38%). National science policies (answer frequency = 0.69) and resources/funding availability (0.62) had a negative influence on scientific vocation. The difficulties to access to scholarships/full-time positions (0.48) had a negative influence mainly for younger researchers. Peer interaction activities were selected as positive factors for scientific vocation, for example work-team (0.51), which also stimulated the generation of new ideas together with the collaboration with other groups (0.76) and conference attendance (0.59). The most frequent publishing strategy to become a full-time researcher was publishing in high impact journals (0.87). However, young researchers mainly chose to make their findings public at conferences (0.57). Time devoted to scientific production was relevant (0.73) and followed by teaching (0.39), although the last was also the least stimulating activity for the generation of new ideas. Three highlights emerge from our results. First, scientific vocation is negatively affected by structural factors related to the scientific system and positively influenced by peer interaction instances. Second, to publish in high impact journals is the most advisable strategy to become a full-time researcher. Third, the most time-demanding activities are not those that most stimulate the generation of ideas. Emerging recommendations for National Science, Technology, and Innovation Ministry, Universities, and/or research organisms for earlycareer Argentine researchers are as follows: increase national science budget, encourage work-team meetings and stays abroad, keep contact with local communities, stakeholders and decision-makers.