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Abstract Arctic rodents influence tundra plant communities by altering species diversity, structure, and nutrient dynamics. These dynamics are intensified during rodent population peaks. Plants are known to induce defenses in response to rodent herbivory. However, changes in plant tissue digestibility may also play a role in deterring rodents or impacting their survival. This study presents a first look at the impacts of rodent herbivory on crude protein (CP) and acid detergent fiber (ADF) of three of the most common graminoid species (Calamagrostis sp.,Carex nigraandDeschampsia cespitosa) in the tundra meadows of the Varanger Peninsula, Norway. We selected 32 experimental plots representing both rodent-disturbed and adjacent, undisturbed control graminoid patches. During a rodent population peak, the disturbed plots had higher ADF (28.5%) values than less disturbed ones (26.6%), controlling for plant species. We also found differences between species, withCarex nigrahaving the lowest fiber content (24.3%, ADF) and highest protein content (18.2% CP) – making it the most palatable species. These results show that rodent activity can potentially alter plant food quality, suggesting that increased fiber content may be a defensive adaptation against herbivory. 

Abstract Science, engineering, and society increasingly require integrative thinking about emerging problems in complex systems, a notion referred to as convergence science. Due to the concurrent pressures of two main stressors—rapid climate change and industrialization, Arctic research demands such a paradigm of scientific inquiry. This perspective represents a synthesis of a vision for its application in Arctic system studies, developed by a group of disciplinary experts consisting of social and earth system scientists, ecologists, and engineers. Our objective is to demonstrate how convergence research questions can be developed via a holistic view of system interactions that are then parsed into material links and concrete inquiries of disciplinary and interdisciplinary nature. We illustrate the application of the convergence science paradigm to several forms of Arctic stressors using the Yamal Peninsula of the Russian Arctic as a representative natural laboratory with a biogeographic gradient from the forest‐tundra ecotone to the high Arctic. 

Abstract Photosynthetic traits suggest that shade tolerance may explain the contrasting success of two conifer taxa, Podocarpaceae and Pinaceae, in tropical forests. Needle‐leaved species fromPinus(Pinaceae) are generally absent from tropical forests, whereasPinus krempfii, a flat‐leaved pine, and numerous flat‐leaved Podocarpaceae are abundant. Respiration (R) traits may provide additional insight into the drivers of the contrasting success of needle‐ and flat‐leaved conifers in tropical forests.We measured the short‐term respiratory temperature (RT) response between 10 and 50°C and foliar morphological traits of three needle‐ and seven flat‐leaved conifer species coexisting in a tropical montane forest in the Central Highlands of Vietnam containing notable conifer diversity. We fit a lognormal polynomial model to each RT curve and extracted the following three parameters:a(basalR), andbandc(together describing the shape of the response).Needle‐leaved species (Pinus kesiya,Pinus dalatensisandDacrydium elatum) had higher rates of area‐basedRat 25°C (R_25‐area) as well as higher area‐based modelled basal respiration (a) than flat‐leaved species (P. krempfii,Podocarpus neriifolius,Dacrycarpus imbricatus,Nageia nana,Taxus wallichiana,Keteeleria evelynianaandFokienia hodginsii). No significant differences were found between needle‐ and flat‐leaved species in mass‐basedR₂₅(R_25‐mass) or in the shape of the RT response (bandc); however, interspecific differences inR_25‐mass,Rat nighttime temperature extremes (R_4.1andR_20.6) and leaf traits were apparent.Differences inR_25‐areaandasuggest that needle‐leaved foliage may be more energetically costly to maintain than flat‐leaved foliage, providing new insight and additional support for the hypothesis that shade tolerance is an important driver of Podocarpaceae success and Pinaceae absence in the majority of tropical forests.Interspecific differences inR_25‐massand leaf traits highlight that varying ecological strategies are employed by conifers to coexist and survive in the Central Highlands of Vietnam. Ultimately, these data further our understanding of current conifer biogeographical distributions and underscore the need for additional studies to elucidate the effects of extreme temperature events on the continued survival of conifers in this unique forest. A freePlain Language Summarycan be found within the Supporting Information of this article.