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Biology subjects

Klanderud, K.

Publications and source records attributed to Klanderud, K..

3 recordsLinked to original sources

Temperature and precipitation interactively shape the plant microbiome by regulating the start of the growing season

Climate change is altering associations between plants and soil microbiota, threatening ecosystem functioning and stability. Predicting these effects requires understanding how concomitant changes in temperature and precipitation influence plant-soil microbiota associations. We identify the pathways via which temperature and precipitation shape prokaryote and fungal rhizosphere and root-associated communities of the perennial grass Festuca rubra in cold-climate ecosystems. We found that interactive effects of temperature and precipitation are key in shaping plant-soil microbiota associations, with the start of the growing season as a critical mediating factor. Specifically, the start of the growing season is advanced by increasing temperature, but delayed by increasing precipitation. This interactive pathway particularly shaped rhizosphere organic matter degrading microbiota, and root-associated plant pathogen and beneficial microbiota. We conclude that understanding local temperature, precipitation, and seasonal changes is crucial to accurately predict how the unique plant-microbiota interactions shaping cold-climate ecosystems are evolving with the ongoing change in climate.

ecology↗

Macro-environment strongly interacts with warming in a global analysis of decomposition

Empirical studies worldwide show substantial variability in plant litter decomposition responses to warming, leaving the overall impact of climate change on this process uncertain. We conducted a meta-analysis of 109 experimental warming studies across seven continents, utilizing natural and standardized plant material, to assess the overarching effect of warming on decomposition and identify potential moderating factors. Warming influences decomposition differently across macro-environmental gradients of moisture and temperature. Negative warming effects on decomposition in warmer, low-moisture areas were counterbalanced by the positive, though not significant, warming effects in colder areas, resulting in an overall non-significant effect. We determine that at least 5.2 degrees of warming is required for a significant increase in decomposition. This is particularly relevant given the past decades global warmth in higher latitudes, holding a significant proportion of terrestrial carbon. Low-quality plant litter was more sensitive to warming. Therefore, future vegetation changes toward low-quality, temperature-sensitive plants could increase carbon release and reduce the net supply of stored organic matter in the soil by increasing the decomposition of low-quality litter with warming. Our findings emphasize the connection between warming responses, macro-environment, and litter characteristics, refining predictions of climate changes consequences on key ecosystem processes and its contextual dependencies.

ecology↗

Dispersal limitation and stage-specific local filtering processes vary with climate across a network of alpine grasslands

Dispersal dynamics and local filtering interactively generate regional vegetation patterns, but empirical evidence of their combined influence in nature is scarce, representing a missing link between our theoretical understanding of community assembly and real-world observation. Here, we compare seed and adult plant communities at twelve grassland sites with different climates in southern Norway to explore the degree to which community membership is shaped by dispersal limitation and local niche-based filtering, and how this varies with climate. To do this, we first divide species at each site into two groups: \"locally-transient\" species, which occur as seeds but are rare or absent as adults (i.e., they arrive but are filtered out), or \"locally-persistent\" species, which occur consistently as adults in annual vegetation surveys. We then ask questions to reveal where, when, why, and how locally-transient species are systematically disfavored during community assembly. Our results led to four main conclusions: (1) the strength of local filtering on community membership increased with temperature, (2) surprisingly, local filtering was stronger during seedling emergence than during seedling establishment, (3) climate-based niche differences drove differential performance among species, especially for seeds dispersing outside of their realized climate niches into more stressful (colder and drier) climates, and (4) locally-transient species had traits that may made them better dispersers (smaller seeds) but poorer competitors for light (shorter statures, less persistent clonal connections) than locally-persistent species, providing a potential explanation for why they arrived to new sites but failed to establish persistent adult populations. Our study is one of the first to combine seed, seedling, and adult survey data across multiple sites with different climates to provide a rigorous empirical evaluation of the combined influence of dispersal limitation and local filtering on the generation and maintenance of climate-associated vegetation patterns.

ecology↗