Alexandru Milcu

Alexandru Milcu
Centre d'Ecologie Fonctionnelle et Evolutive | CEFE · Functional Ecology

PhD in Ecology

About

112
Publications
38,842
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
4,520
Citations
Citations since 2016
63 Research Items
3355 Citations
20162017201820192020202120220100200300400500600
20162017201820192020202120220100200300400500600
20162017201820192020202120220100200300400500600
20162017201820192020202120220100200300400500600
Introduction
I am an ecosystem ecologist interested in the consequences of biodiversity loss and climate change for the functioning of terrestrial ecosystems. In my research I often take advantage of controlled environment facilities for ecosystem research (ECOTRONs) for their capacity to measure ecosystem-level of carbon and water fluxes while controlling the environmental conditions. Websites: http://www.cefe.cnrs.fr/fr/recherche/ef/bioflux http://www.ecotron.cnrs.fr/
Additional affiliations
July 2018 - present
CNRS Ecotron
Position
  • Research Director
October 2014 - present
CNRS, Centre d'Ecologie Fonctionnelle et Evolutive
Position
  • Researcher (CR1)
March 2012 - July 2018
CNRS Ecotron
Position
  • Research Associate

Publications

Publications (112)
Article
Full-text available
Ecosystems integrity and services are threatened by anthropogenic global changes. Mitigating and adapting to these changes requires knowledge of ecosystem functioning in the expected novel environments, informed in large part through experimentation and modelling. This paper describes 13 advanced controlled environment facilities for experimental e...
Article
Full-text available
Earth is home to over 350,000 vascular plant species that differ in their traits in innumerable ways. A key challenge is to pre- dict how natural or anthropogenically driven changes in the identity, abundance and diversity of co-occurring plant species drive important ecosystem-level properties such as biomass production or carbon storage. Here, we...
Article
Full-text available
Significance Ecosystems are responding to climate change and increasing atmospheric CO 2 concentrations. Interactions between these factors have rarely been assessed experimentally during and after extreme climate events despite their predicted increase in intensity and frequency and their negative impact on primary productivity and soil carbon sto...
Article
Full-text available
Many scientific disciplines are currently experiencing a 'reproducibility crisis' because numerous scientific findings cannot be repeated consistently. A novel but controversial hypothesis postulates that stringent levels of environmental and biotic standardization in experimental studies reduce reproducibility by amplifying the impacts of laborato...
Preprint
Full-text available
Earthworms can stimulate plant productivity, but their impact on soil greenhouse gases (GHG) is still debated. Methodological challenges of measuring GHG in experiments with plants are presumably contributing to the status quo, with the majority of studies being conducted without plants. Here we report the effect of earthworms (without, anecic, end...
Preprint
Full-text available
The isotopic composition of dioxygen in the atmosphere is a global tracer which depends on the biosphere flux of dioxygen toward and from the atmosphere (photosynthesis and respiration) as well as exchanges with the stratosphere. When measured in fossil air trapped in ice cores, the relative concentration of 16O, 17O and 18O of O2 can be used for s...
Article
Full-text available
Plant community composition influences soil microbial communities through plant trait variations that lead to changes in nutrient and organic carbon inputs into the soil by root exudates and plant litter. Although plant litter and living roots are known to influence microbial functioning independently, their relative effects are rarely measured sim...
Article
Full-text available
Plant diversity is an important driver of below‐ground ecosystem functions, such as root growth, soil organic matter (SOM) storage and microbial metabolism, mainly by influencing the interactions between plant roots and soil. Dissolved organic matter (DOM), as the most mobile form of SOM, plays a crucial role for a multitude of soil processes that...
Article
The importance of species richness to ecosystem functioning and services is a central tenet of biological conservation. However, most of our theory and mechanistic understanding is based on diversity found aboveground. Our study sought to better understand the relationship between diversity and belowground function by studying root biomass across a...
Article
Full-text available
The circadian clock is a molecular timer of metabolism that affects the diurnal pattern of stomatal conductance (gs), amongst other processes, in a broad array of plant species. The function of circadian gs regulation remains unknown and here, we test whether circadian regulation helps to optimize diurnal variations in stomatal conductance. We subj...
Article
Full-text available
Predicted increases in drought frequency and severity may change soil microbial functioning. Microbial resistance and recovery to drought depend on plant community characteristics, among other factors, yet how changes in plant diversity modify microbial drought responses is uncertain. Here, we assessed how repeated drying-rewetting cycles affect so...
Article
Full-text available
The success of tree recruitment in Mediterranean holm oak (Quercus ilex) forests is threatened by the increasing intensity, duration and frequency of drought periods. Seedling germination and growth are modulated by complex interactions between abiotic (microhabitat conditions) and biotic factors (mycorrhiza association) that may mitigate the impac...
Preprint
Full-text available
The success of tree recruitment in Mediterranean Quercus ilex forests is threatened by the increasing intensity, duration and frequency of drought periods. Seedling germination and growth are modulated by complex interactions between abiotic (microhabitat conditions) and biotic factors (mycorrhiza association) that may mitigate the impacts of clima...
Article
Full-text available
Long generation times have been suggested to hamper rapid genetic adaptation of organisms to changing environmental conditions. We examined if environmental memory of the parental Scots pines (Pinus sylvestris L.) drive offspring survival and growth. We used seeds from trees growing under naturally dry conditions (control), irrigated trees (irrigat...
Article
Full-text available
Aims There is evidence that different facets of biodiversity such as species richness (SR), phylogenetic diversity (PD) and functional diversity (FD) can modulate ecosystem functioning via niche-complementarity or mass-ratio effects, but the support for these hypotheses on fine root biomass remains unclear. Methods In a tree diversity gradient in...
Preprint
Full-text available
Earth is home to over 350,000 vascular plant species ¹ that differ in their traits in innumerable ways. Yet, a handful of functional traits can help explaining major differences among species in photosynthetic rate, growth rate, reproductive output and other aspects of plant performance 2–6 . A key challenge, coined “the Holy Grail” in ecology, is...
Conference Paper
Full-text available
Geotechnical operations such as embankments construction influence soil carbon (C) storage since massive amounts of C-poor subsoil are brought to the surface. We hypothesize that subsoil can sequester relatively more C than C-rich topsoil due to its lower C-saturation. We excavated topsoil (0.0 to 0.3 m) and subsoil (1.1 to 1.4 m) from the same pro...
Article
Full-text available
Critical examination of the approaches ecologists employ to understand complex ecological systems is integral to advancing our science. Recently, Korell et al. (2019) argued that climate change experiments would yield more relevant information on future functioning of ecosystems if the treatments imposed more closely reflected model‐projected clima...
Article
Full-text available
Locally, plant species richness supports many ecosystem functions. Yet, the mechanisms driving these often‐positive biodiversity–ecosystem functioning relationships are not well understood. Spatial resource partitioning across vertical resource gradients is one of the main hypothesized causes for enhanced ecosystem functioning in more biodiverse gr...
Article
Full-text available
Climate and plant diversity are major determinants of carbon (C) and nitrogen (N) dynamics in decomposing plant litter. However, the direction and extent to which these dynamics are affected by combined changes in climate and biodiversity are not well understood. We used a field experiment in a Mediterranean shrubland ranging from one to four shrub...
Article
Full-text available
Numerous experiments have shown positive diversity effects on plant productivity, but little is known about related processes of carbon gain and allocation. We investigated these processes in a controlled environment (Montpellier European Ecotron) applying a continuous ¹³CO2 label for three weeks to 12 soil-vegetation monoliths originating from a g...
Data
Average air δ13C-CO2 signature during the pre-enrichment phase and daily means of δ13C-CO2 at the outlet of the experimental units based on measurements every two hours during the period of continuous atmospheric 13CO2 labelling. (PDF)
Data
Species composition of studied mixtures. (PDF)
Data
Analysis of leaf non-structural carbohydrate concentrations and δ13C in relation to species richness and functional groups. (PDF)
Data
Analysis of leaf non-structural carbohydrate concentrations and δ13C in relation to functional traits. (PDF)
Data
Analysis of functional traits in relation to species richness and functional group identity. (PDF)
Data
Data on species-level shoot biomass, δ13C in shoot biomass. (PDF)
Data
Data on non-structural carbohydrate concentrations and δ13C in bulk shoot and root samples. (PDF)
Data
Data on non-structural carbohydrate concentrations and δ13C in leaf samples. (PDF)
Data
Measurement of aboveground functional traits. (PDF)
Data
Analysis of community-level shoot 13C abundance and 13C excess in relation to functional composition. (PDF)
Data
Scatterplots between species-level 13C abundance in shoots and functional traits. (PDF)
Data
Non-structural carbohydrate concentrations and δ13C in relation to functional groups. (PDF)
Chapter
Full-text available
Concern about the functional consequences of unprecedented loss in biodiversity has prompted biodiversity-ecosystem functioning (BEF) research to become one of the most active fields of ecological research in the past 25 years. Hundreds of experiments have manipulated biodiversity as an independent variable and found compelling support that the fun...
Article
Evidence suggests that biodiversity supports ecosystem functioning. Yet, the mechanisms driving this relationship remain unclear. Complementarity is one common explanation for these positive biodiversity–ecosystem functioning relationships. Yet, complementarity is often indirectly quantified as overperformance in mixture relative to monoculture (e....
Preprint
Full-text available
Numerous experiments have shown positive diversity effects on plant productivity, but little is known about related processes of carbon gain and allocation. We investigated these processes in a controlled environment (Montpellier European Ecotron) applying a continuous 13CO2 label for three weeks to 12 soil-vegetation monoliths originating from a g...
Article
Leaf litter mixtures and the amount of litter biomass in the litter standing stocks can affect the decomposition rates by modifying physical properties and resource heterogeneity in the litter layers. However, the potential interactive effects of litter mixtures and the amount of litter biomass on decomposition have been overlooked in the literatur...
Article
Full-text available
Models predict that vertical gradients of foliar nitrogen (N) allocation, increasing from bottom to top of plant canopies, emerge as a plastic response to optimise N utilisation for carbon assimilation. While this mechanism has been well documented in monocultures, its relevance for mixed stands of varying species richness remains poorly understood...
Poster
Full-text available
This poster aims to describe the aims and methodology implemented at Ecotron (Montpellier) to study differences in carbon sequestration between top organic soil and deep mineral soils
Article
Full-text available
1.Efficient extraction of soil water is essential for the productivity of plant communities. However, research on the complementary use of resources in mixed plant communities, and especially the impact of plant species richness on root water uptake, is limited. So far, these investigations have been hindered by a lack of methods allowing for the e...
Preprint
Full-text available
Optimal stomatal theory is an evolutionary model proposing that leaves trade-off Carbon (C) for water to maximise C assimilation ( A ) and minimise transpiration ( E ), thereby generating a marginal water cost of carbon gain (λ) that remains constant over short temporal scales. The circadian clock is a molecular timer of metabolism that controls A...
Article
Full-text available
In the past two decades, a large number of studies have investigated the relationship between biodiversity and ecosystem functioning, most of which focussed on a limited set of ecosystem variables. The Jena Experiment was set up in 2002 to investigate the effects of plant diversity on element cycling and trophic interactions, using a multi-discipli...
Article
Full-text available
Different tree species influence litter decomposition directly through species-specific litter traits, and indirectly through distinct modifications of the local decomposition environment. Whether these indirect effects on decomposition are influenced by tree species diversity is presently not clear. We addressed this question by studying the decom...
Article
Studies on the dependence of the rates of ecosystem gas exchange on environmental parameters often rely on the up-scaling of leaf-level response curves (‘bottom-up’ approach), and/or the down-scaling of ecosystem fluxes (‘top-down’ approach), where one takes advantage of the natural diurnal covariation between the parameter of interest and photosyn...
Article
Full-text available
This study aimed at quantifying the consequences of reduced precipitation and plant diversity on soil microbial community functioning in a Mediterranean shrubland of southern France. Across a natural gradient of shrub species diversity, we established a total of 92 plots (4 × 4 m) with and without a moderate rain exclusion treatment of about 12 % o...
Article
Full-text available
Abstract The potential of the vegetation to sequester C is determined by the balance between assimilation and respiration. Respiration is under environmental and substrate-driven control, but the circadian clock might also contribute. To assess circadian control on night-time dark respiration (RD) and on light enhanced dark respiration (LEDR) − the...
Article
Full-text available
There is increasing evidence that the circadian clock is a significant driver of photosynthesis that becomes apparent when environmental cues are experimentally held constant. We studied whether the composition of photosynthetic pigments is under circadian regulation, and whether pigment oscillations lead to rhythmic changes in photochemical effici...
Article
Full-text available
Human-caused declines in biodiversity have stimulated intensive research on the consequences of biodiversity loss for ecosystem services and policy initiatives to preserve the functioning of ecosystems. Short-term biodiversity experiments have documented positive effects of plant species richness on many ecosystem functions, and longer-term studies...
Article
Full-text available
Higher plant diversity reduces nitrate leaching by complementary resource use, while its relation to leaching of other N species is unclear. We determined the effects of plant species richness, functional group richness, and the presence of specific functional groups on ammonium, dissolved organic N (DON), and total dissolved N (TDN) leaching from...
Article
Full-text available
Background Molecular clocks drive oscillations in leaf photosynthesis, stomatal conductance, and other cell and leaf-level processes over ~24 h under controlled laboratory conditions. The influence of such circadian regulation over whole-canopy fluxes remains uncertain; diurnal CO2 and H2O vapor flux dynamics in the field are currently interpreted...
Conference Paper
Full-text available
The ability to control environmental conditions while simultaneously measure ecosystem-level carbon and water fluxes, makes controlled environment facilities for ecosystem research (Ecotrons) useful tools for understanding the responses of ecosystems to global changes. Here we present the key findings from two experiments, one investigating the res...
Preprint
Full-text available
Molecular clocks drive oscillations in leaf photosynthesis, stomatal conductance and other cell and leaf level processes over ~24 h under controlled laboratory conditions. The influence of such circadian regulation over whole canopy fluxes remains uncertain and diurnal CO 2 and H 2 O vapor flux dynamics in the field are currently interpreted as res...
Conference Paper
Full-text available
University of Innsbruck, (5) Ecotron, CNRS Plants are sessile and poikilothermic organisms that need to respond and adjust promptly to an ever-changing environment. Over a single 24 h period, a plant may experience the same level of variation in radiation as in its entire lifetime and, in some climates, the oscillation in day-night temperature and...
Poster
Full-text available
Effects of species and functional diversity of plants on ecosystem evapotranspiration and carbon fluxes have been rarely assessed simultaneously. Here we present the results from an experiment that combined a lysimeter setup in a controlled environment facility (Ecotron) with large ecosystem samples/ monoliths originating from a longterm biodiversi...
Article
The impact of species richness and functional diversity of plants on ecosystem water vapor fluxes has been little investigated. To address this knowledge gap, we combined a lysimeter setup in a controlled environment facility (Ecotron) with large ecosystem samples/monoliths originating from a long-term biodiversity experiment (The Jena Experiment)...