Pierre Liancourt

State Museum of Natural History Stuttgart | SMNS · Department of Botany

Predicting the future of any given species represents an unprecedented challenge in light of the many environmental and biological factors that affect organismal performance and that also interact with drivers of global change. In a three-year experiment set in the Mongolian steppe, we examined the response of the common grass Festuca lenensis to m...

Climate change is expected to modify plant assemblages in ways that will have major consequences for ecosystem functions. How climate change will affect community composition will depend on how individual species respond, which is likely related to interspecific differences in functional traits. The extraordinary plasticity of some plant traits is...

Background and aims: The stress gradient hypothesis (SGH), the view that competition prevails in undisturbed and productive environments, and shifts to facilitation in disturbed or stressful environments, has become a central paradigm in ecology. However, an alternative view proposes that the relationship between biotic interactions and environmen...

Understanding the relationship between biodiversity and ecosystem functioning has been a core ecological research topic over the past decades. Although a key hypothesis is that the diversity of functional traits determines ecosystem functioning, we do not know how much trait diversity is needed to maintain multiple ecosystem functions simultaneousl...

Explaining species geographic distributions by macroclimate variables is the most common approach for getting mechanistic insights into large scale diversity patterns and range shifts. However, species’ traits influencing biophysical processes can produce a large decoupling from ambient air temperature, which can seriously undermine biogeographical...

Belowground niche partitioning presents a key mechanism maintaining species coexistence and diversity. Its importance is currently reinforced by climate change that alters soil hydrological conditions. However, experimental tests examining the magnitude of its change under climate change are scarce. We combined measurements of oxygen stable isotope...

Plant lifespan has important evolutionary, physiological, and ecological implications related to population persistence, community stability, and resilience to ongoing environmental change impacts. Although biologists have long been puzzled over the extraordinary variation in plant lifespan and its causes, our understanding of interspe-cific variab...

Plant lifespan has important evolutionary, physiological, and ecological implications related to population persistence, community stability, and resilience to ongoing environmental change impacts. Although biologists have long puzzled over the extraordinary variation in plant lifespan and its causes, our understanding of interspecific variability...

Grazing represents the most extensive use of land worldwide. Yet its impacts on ecosystem services remain uncertain because pervasive interactions between grazing pressure, climate, soil properties, and biodiversity may occur but have never been addressed simultaneously. Using a standardized survey at 98 sites across six continents, we show that in...

The relationship between competition and productivity in plant communities is unclear, likely due to (i) a confusion in the literature between productivity and biomass, (ii) the lack of studies assessing variation in competition in all combinations of biomass and productivity. We assessed the outcome of plant‐plant interactions by removing neighbor...

Invasions of alien plants pose a serious threat to native biodiversity and ecosystem processes. Forests are considered more resistant to invasion due to limited light availability in understories. However, disturbance and abiotic stress may open tree canopies and promote invasion. Their combined effects together with the resistance of resident spec...

Nonstructural carbohydrates (NSC) are the crucial components of plant metabolism, and NSC dynamics provide essential information on plant carbon balance, which usually changes toward the distribution limits of plants. NSC have been extensively used to study the elevational limit in trees all around the world. For alpine herbs, which occupy vast are...

Under climate change, extreme droughts will limit water availability for plants. However, the species‐specific responses make it difficult to draw general conclusions. We hypothesized that changes in species’ abundance in response to extreme drought can be best explained by a set of water economic traits under ambient conditions in combination with...

Question Which vegetation and soil parameters limit species establishment in restored grasslands? Do these parameters operate predominantly on a fine or a community scale? Location White Carpathian Mountains, SE Czech Republic. Methods We compared 16 grasslands restored on former arable land with 9 well‐preserved reference grasslands. We sampled...

Aim Untangling multiple drivers influencing biodiversity along elevation gradients is necessary for predicting the consequences of climate change on mountain communities. We examine the direct and indirect effects of macroclimate, edaphic conditions, fire frequency and putative biotic interactions on species richness and abundance of co‐occurring p...

Both chemical and physical properties of soils have been used for two centuries for explaining differences in species composition and diversity between plant communities from calcareous and siliceous soils. Here, we examine the prediction from the ‘physical hypothesis’, which proposes that species from siliceous soils are absent from calcareous soi...

Deciphering the effect of neutral and deterministic processes on community assembly is critical to understand and predict diversity patterns. The information held in community trait distributions is commonly assumed as a signature of these processes, but empirical and modelling attempts have most often failed to untangle their confounding, sometime...

Increased drought is predicted to have a major impact on plant performance under environmental change. Yet leaf hydraulic traits directly related to drought tolerance, such as leaf turgor loss point ( π tlp ), are under‐represented in trait‐based studies and have been largely overlooked within the main frameworks evaluating trait–trait coordination...

How the relationship between species richness and productivity changes along environmental gradients remains poorly understood. We examined the context dependency of complementarity processes underpinning this relationship (biotic feedbacks, resource partitioning and facilitation) using the framework of Grime's (1973) humped‐back model. We consider...

The habitat fragmentation and isolation threaten populations of rare species. Organisms become endangered because of the primary habitat loss, but also due to limited dispersal capacity. Whether threatened species are limited more by their dispersal capacity or by lack of suitable habitats is an unresolved question critical to effective conservatio...

Understanding how climate influences plant reproduction and growth at contrasting range limits is crucial for predicting how species' ranges may shift in response to ongoing climate change. Trees and shrubs have shown warming‐induced increases in performance at upper elevation limits but reduced performance at lower distributional limits due to war...

The large majority of ‘facilitation studies’ focus on benefactor–beneficiary interactions. However, this may skew our view of the role of facilitation toward systems where it is most conspicuous, and perhaps toward harsh environments where discrete vegetation cover and pattern suggestive of facilitation are more common. Here we argue that a particu...

The study of insular systems has a long history in ecology and biogeography. Island plants often differ remarkably from their noninsular counterparts, constituting excellent models for exploring eco-evolutionary processes. Trait-based approaches can help to answer important questions in island biogeography, yet plant trait patterns on islands remai...

Abstract Questions We asked how plant community composition responded to experimentally produced warmer and drier climate conditions at the landscape scale with existing variation in local species composition and environmental conditions. We aimed to identify changes in community composition overall and the species with greatest response in abundan...

Background and aims: Alpine cushion plants can initially facilitate other species during ecological succession, but later on can be negatively affected by their development, especially when beneficiaries possess traits allowing them to overrun their host. This can be reinforced by accelerated warming favouring competitively strong species over col...

1.Understanding what determines the high elevation limits of trees is crucial for predicting how treelines may shift in response to climate change. Treeline formation is commonly explained by a low‐temperature restriction of meristematic activity (sink limitation) rather than carbon assimilation (source limitation). In arid mountains, however, tree...

Global climate change is affecting and will continue to affect ecosystems worldwide. Specifically, temperature and precipitation are both expected to shift globally, and their separate and interactive effects will likely affect ecosystems differentially depending on current temperature, precipitation regimes, and other biotic and environmental fact...

Mountain plant diversity results from a myriad of factors, including evolutionary history, species pools, abiotic and biotic constraints. For instance, increasing stress (e.g., elevation) often selects communities with species originating from fewer, and more closely-related clades. We assessed phylogenetic diversity and turnover of plant communiti...

Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about mi...

The environmental filtering hypothesis predicts that the abiotic environment selects species with similar trait values within communities. Testing this hypothesis along multiple – and interacting – gradients of climate and soil variables constitutes a great opportunity to better understand and predict the responses of plant communities to ongoing e...

A rapid warming in Himalayas is predicted to increase plant upper distributional limits, vegetation cover and abundance of species adapted to warmer climate. We explored these predictions in NW Himalayas, by revisiting uppermost plant populations after ten years (2003–2013), detailed monitoring of vegetation changes in permanent plots (2009–2012),...

It is trite to say “publish or perish,” yet many early career researchers are often at a loss on how to best get one’s work published. With strong competition and many manuscripts submitted, it is difficult to convince editors and reviewers to opt for acceptance. A pragmatic approach to publishing may increase one’s odds of success. Here, we-- a gr...

Vascular plants in the western Tibetan Plateau reach 6000 m-the highest elevation on Earth. Due to the significant warming of the region, plant ranges are expected to shift upwards. However, factors governing maximum elevational limits of plant are unclear. To experimentally assess these factors, we transplanted 12 species from 5750 m to 5900 m (up...

The skewness and kurtosis of community trait distributions (CTDs) can provide important insights on the mechanisms driving community assembly and species coexistence. However, they have not been considered yet when describing global patterns in CTDs. We aimed to do so by evaluating how environmental variables (mean annual temperature [MAT] and prec...

The skewness and kurtosis of community trait distributions (CTDs) can provide important insights on the mechanisms driving community assembly and species coexistence. However, they have not been considered yet when describing global patterns in CTDs. We aimed to do so by evaluating how environmental variables (mean annual temperature [MAT] and prec...

Abstract Questions: How does plant productivity and community composition in the mountain steppe of northern Mongolia respond to increased precipitation? Do these changes differ with the timing of precipitation? Location: Mountain steppe at ecotone between steppe and taiga, Dalbay Valley, Lake Ho€vsgo€l International Long Term Ecological Research...

Alien and native plant species often differ in functional traits. Trait differences could lead to niche differences that minimize competitive interactions and stabilize coexistence. However, trait differences could also translate into average fitness differences, leading to a competitive hierarchy that prevents coexistence. We tested whether trait...

The capability of ecosystems to deliver services, such as agricultural production, in the future is largely dependent upon human land use. Land use change resulting in habitat loss negatively alters ecosystem services. In particular, services mobile organisms provide, such as insects and wild pollination, are negatively impacted. Negative effects o...

Background/Question/Methods Maintaining species interactions is critical to preserving important ecological services. Land use change can alter biodiversity directly and trophic interactions indirectly. Commonly, the changes involve modifications to active land management, such as increases in agricultural intensity or urbanization. However, the...

Background/Question/Methods Some of the most diverse bacterial communities are found in soils.Very little is known about temporal and spatial variation in the composition of soil bacterial communities and the drivers of these differences. We undertook a multi-year experiment to test effects of climate change and grazing on soil bacterial communit...

Socio-economic changes threaten nomadic pastoralism across the world, changing traditional grazing patterns. Such land-use changes will co-occur with climate change, and while both are potentially important determinants of future ecosystem functioning, interactions between them remain poorly understood. We investigated the effects of grazing by lar...

1.The importance of competition has been defined as the impact or role of competition relative to the total impact of the environment, and the intensity of competition is its absolute impact. Understanding the distinction has been proposed as key in reconciling long-running ecological debates. 2.An index of competition importance, Cimp, has been u...

Background/Question/Methods Soils are amongst the most biodiverse habitats on the planet. Bacteria constitute a significant portion of this diversity, yet neither the impact of bacterial diversity on an ecosystem, nor the drivers that shape this diversity are well understood. An especially pressing question is how soil bacterial communities may b...

Background/Question/Methods Community-level pollination studies have increasingly used network analysis to describe the visitation of pollinator species to plant species. Many focus on network topology rather than the basic biotic and abiotic factors shaping plant-pollinator interactions. Our work is motivated by sources of variation in plant-pol...

Background/Question/Methods Societal and economic changes threaten traditional practices of nomadic pastoralism worldwide, sometimes altering grazing patterns that have been in place for millennia. Climate change is occurring simultaneously. While both are likely to affect ecosystem functioning, interactions between the two are poorly studied. In...

QuestionWhat are the interacting effects of stress and disturbance on both competition and facilitation, and ultimately their impact on diversity and species ranges? LocationSimulated data. Method We extended the spatially explicit model of Xiao etal. (Oikos, 118, 2009, 1343) to consider how stress and disturbance - operating alone or together - af...

Background/Question/Methods Recent monitoring in the Lake Hövsgöl region of northern Mongolia has shown that mean annual air temperature has increased by 1.8 °C over the last 40 years, greater than global average temperature increases. Although it is hypothesized that warmer temperatures will cause greater soil CO2 efflux, responses of soil efflu...

Topography should create spatial variation in water and nutrients and play an especially important role in the ecology of water-limited systems. We use stable isotopes to discern how plants respond both to ecological gradients associated with elevation and to neighboring legumes on a south-facing slope in the semi-arid, historically grazed steppe o...

The semiarid, northern Mongolian steppe, which still supports pastoral nomads who have used the steppe for millennia, has experienced an average 1.78C temperature rise over the past 40 years. Continuing climate change is likely to affect flowering phenology and flower numbers with potentially important consequences for plant community composition,...

The semiarid, northern Mongolian steppe, which still supports pastoral nomads who have used the steppe for millennia, has experienced an average 1.7 degrees C temperature rise over the past 40 years. Continuing climate change is likely to affect flowering phenology and flower numbers with potentially important consequences for plant community compo...

Adler et al. (Reports, 23 September 2011, p. 1750) reported “weak and variable” relationships between productivity and species richness and dispute the “humped-back” model (HBM) of plant diversity. We show that their analysis lacks sufficient high-productivity sites, ignores litter, and excludes anthropogenic sites. If corrected, the data set of Ad...

Compared to the vast literature linking competitive interactions and speciation, attempts to understand the role of facilitation for evolutionary diversification remain scarce. Yet, community ecologists now recognize the importance of positive interactions within plant communities. Here, we examine how facilitation may interfere with the mechanisms...