Functional ecology often analyses a few selected traits and relates them either to environmental conditions or ecosystem properties. However, not the individual trait, but the whole plant with a set ...of coordinated traits responds to the environment or affects ecosystem properties. Here we argue that the correlation among traits of all major plant organs should be an integral part of response or effect studies. Plants allocate elements and biomass among roots, perennial clonal organs, stems, leaves and seeds to ensure growth and reproduction. Assessment of trait responses to the environment and effects on ecosystems is hardly possible without simultaneously considering all plant organs and the biological functions they perform, namely resource uptake, vegetative regeneration, support and hydraulic pathways, photosynthesis and generative reproduction. Suitable traits to indicate these functions include those of mass, density, size, volume, and element contents of the main plant organs. In principle, we do not propose to collect many traits, but those of similar significance across organs. For instance, specific leaf area should be complemented by specific root length and specific stem length. We present some thoughts on how coordinated allocation to biological functions sets boundaries to the range of trait expressions in successional series and consequently also to species responses to the environment and effects on ecosystems. Considering the coordination of traits amongst all major plant organs will improve our understanding of plant strategies ensuring survival in patterned landscapes.
Die funktionelle Ökologie analysiert häufig nur einige wenige ausgewählte biologische Merkmale und setzt sie mit Umweltbedingungen oder Ökosystemeigenschaften in Beziehung. Allerdings reagiert nicht nur das einzelne ausgewählte Merkmal auf Umweltveränderungen bzw. beeinflusst Ökosystemeigenschaften, sondern die ganze Pflanze mit einer Reihe untereinander koordinierter Merkmale. Wir vertreten die Auffassung, dass die Korrelationen zwischen Merkmalen aller relevanten Pflanzenorgane integraler Bestandteil von Untersuchungen sein sollten, welche Merkmale in Bezug zur Umwelt setzen. Gefäßpflanzen verteilen Elemente und Biomasse auf Wurzeln, klonale Organe wie Rhizome, Stängel, Blätter und Samen, um Wachstum und Reproduktion sicherzustellen. Die Bewertung von Reaktionen von biologischen Merkmalen auf die Umwelt oder ihres Effektes auf Ökosystemeigenschaften sind kaum möglich, wenn nicht alle Organe und ihre biologischen Funktionen berücksichtigt werden, namentlich Nährstoffaufnahme, vegetative Regeneration, Stützfunktionen und Wassertransport, Photosynthese und generative Reproduktion. Geeignete Merkmale, die diese Funktionen kennzeichnen können, sind unter anderem Masse, Dichte, Größe, Volumen und Elementgehalt der Pflanzenorgane. Es kommt unserer Meinung nach nicht auf die Quantität von Traits an, die an einem Individuum bestimmt werden, sondern auf solche mit ähnlicher Bedeutung. So sollte die spezifische Blattfläche mit spezifischer Wurzel- und Stängellänge ergänzt werden. Im Folgenden diskutieren wir, wie eine koordinierte Allokation zu den wichtigsten biologischen Funktionen den Umfang an Merkmalsexpressionen in Sukzessionsserien begrenzt und damit auch die Reaktionen von Arten auf die Umwelt sowie ihre Effekte auf Ökosystemeigenschaften. Die Berücksichtigung der Merkmalskorrelationen aller Organe kann unser Verständnis von Pflanzenstrategien wesentlich verbessern.
Pampered inside, pestered outside? Poorter, Hendrik; Fiorani, Fabio; Pieruschka, Roland ...
The New phytologist,
December 2016, Letnik:
212, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Plant biologists often grow plants in growth chambers or glasshouses with the ultimate aim to understand or improve plant performance in the field. What is often overlooked is how results from ...controlled conditions translate back to field situations. A meta-analysis showed that labgrown plants had faster growth rates, higher nitrogen concentrations and different morphology. They remained smaller, however, because the lab plants had grown for a much shorter time.We compared glasshouse and growth chamber conditions with those in the field and found that the ratio between the daily amount of light and daily temperature (photothermal ratio) was consistently lower under controlled conditions. This may strongly affect a plant’s source: sink ratio and hence its overall morphology and physiology. Plants in the field also grow at higher plant densities. A second meta-analysis showed that a doubling in density leads on average to 34% smaller plants with strong negative effects on tiller or side-shoot formation but little effect on plant height. We found the r
2 between lab and field phenotypic data to be rather modest (0.26). Based on these insights, we discuss various alternatives to facilitate the translation from lab results to the field, including several options to apply growth regimes closer to field conditions.
QUESTIONS: As biodiversity losses increase due to global change and human‐induced habitat destruction, the relationships between plant traits and ecosystem properties can provide a new level of ...understanding ecosystem complexity. Using a functional response–effect approach, we show that multiple components of the carbon cycle are determined by a few plant traits, which in turn are strongly affected by environmental conditions. LOCATION: Salt marshes, northwest Germany. METHODS: We explored responses of morphological, chemical and biomass‐related plant traits to environmental drivers and examined their effects on carbon cycle properties, i.e. above‐ground biomass, above‐ground net primary productivity and decomposition. The combined analysis between environmental parameters, functional traits and ecosystem properties used structural equation modelling (SEM). RESULTS: Important response and effect traits were leaf dry matter content (LDMC) and below‐ground dry mass (BDM, responding to groundwater level and salinity) and leaf C:N ratio (responding to inundation frequency). Inundation and salinity led to increased allocation to below‐ground biomass and salt stress adaptation in leaves, which translated into increased decomposition rates. Release from these abiotic controls resulted in standing biomass accumulation, which was controlled by LDMC and canopy height as key traits. CONCLUSIONS: These findings demonstrate the interacting effects of non‐consumable environmental factors and soil resources on morphological, chemical and biomass traits, which affected carbon cycle properties. Loss of species from the community has the potential to change the relationships between environment and vegetation‐based ecosystem properties and therefore elicit effects on the multifunctionality of the entire and adjacent ecosystems.
Question: How do multivariate methods perform in relating species- and community-level trait responses to the environment? Location: (1) Field data from grazed semi-natural grasslands, NE Germany; ...(2) artificial data. Methods: Research questions associated with trait—environment relationships were briefly reviewed and seven available methods evaluated. The main distinction between research questions is whether trait—environment relationships should be addressed at community or species level. A redundancy analysis (RDA) of mean trait values of species in a plot weighted by their abundances (CWM-RDA) is exclusively suitable for the community level. The other six methods address the species level. A double inertia analysis of two arrays (RLQ) and double canonical correspondence analysis (double CCA) use combinations of ordinations to simultaneously analyse species and trait responses to the environment. A combination of the outlying mean index with generalized additive models (OMI-GAM) predicts the response of species to environmental variables on trait gradients. RDA-RegTree first analyses species responses to the environment with RDA and then uses a regression tree to classify trait expressions according to scores of species responses on the ordination axes. Cluster regression uses cluster analyses and logistic regression to search for trait combinations with the best response to the environmental variables. This method models the distribution of functional groups on environmental gradients. All methods and data are available as R scripts. Results: All methods consistently revealed the main trait responses to environment in the field data set, namely that life history was associated with available phosphorus while grazing intensity was related to leaf C:N ratio and canopy height. At community level, CWM-RDA gave a good overview of trait— environment relationships, as also provided by the species-based methods RLQ and double CCA. OMI-GAM revealed non-linear relationships in the field data set. Field and artificial data gave that the number and stability of functional groups produced by Cluster regression and RDA-RegTree varied more strongly than RLQ, double CCA and OMI-GAM. Conclusions: Each method addresses particular ecological concepts and research questions. If a user asks for the response of average trait expressions of communities to environmental gradients, CWM-RDA may be the first choice. However, species-based methods should be applied to address questions regarding co-existence of different life histories or to assess how groups of species respond to environmental changes. The artificial data set revealed that the methods differed in sensitivity to gradient lengths and random data.
The ecosystem services concept has been introduced as a decisive approach to include ecosystem functioning in land-use planning and stakeholder-driven sustainable development. Early integration of ...stakeholders in participatory processes in the nexus of ecosystem services, climate adaption, and land-use management is still a demanding challenge. This investigation followed a cognitive approach to archetype analysis. We defined cognitive archetypes as recurrent patterns in individual perceptions of social-ecological relations. Our aim was to identify cognitive archetypes based on stakeholders' perceived relation between land-use elements and ecosystem services as exemplified in a German North Sea coastal region. Land-use elements were spatially explicit and delivered a variety of different ecosystem services. The stakeholders were regional decision makers and experts who represented key societal sectors, i.e., water management, agriculture, nature conservation, regional policy, and tourism. Within a participatory process, these stakeholders individually evaluated a matrix of 19 land-use elements and 18 ecosystem services. In terms of archetype analysis, the stakeholders were considered as different cases, and the evaluation of relationships between land-use elements and ecosystem services built the attributions to identify archetypes. They independently agreed on the relevance of close to one-third of 342 attributions, whereas there was disagreement on approximately two-thirds of the possible attributions. By identifying agreements across different sectors, 2 archetypes in land-use element–ecosystem service attributions were identified. The first archetype built on monofunctional attributions, i.e., one land-use element was relevant for the provision of one ecosystem service. The second archetype described land-use elements attributed to bundles of ecosystem services, indicating multifunctionality of land-use elements. Disagreement can result primarily from sector or individual viewpoints. In the case of disagreements, land-use–ecosystem relationships can reveal archetypical mutually exclusive interests, the third archetype. We found that disagreements were mainly individual and not sector specific. This indicated that individual knowledge on service outputs of multiple land uses differed strongly among the stakeholders, particularly with respect to regulatory services.
•An unprecedented set of plots with soil and management data, plant species cover and traits.•Relevant for herbaceous agricultural plant communities in northwest Europe.•Predictions to estimate farm ...income, plant rarity and soil carbon contents from plant traits.•Trade-offs favoring either high farm income, species conservation, or high carbon sequestration.
Although well recognised in ecology, the concept of ecosystem services is still not widely applied in practical environmental planning. Environmental planning often has to evaluate whole landscapes in a spatially explicit way, including marginal landscape elements for which data on provisional, regulatory, and cultural ecosystem properties and services are not readily available or are costly to provide. On the other hand, many planning schemes include a habitat- or vegetation survey, raising the question whether ecosystem services can be predicted from vegetation properties alone. I used a large data set of herbaceous plant communities collected across Germany, The Netherlands, and Denmark, as well as additional data, to predict (i) the probability of obtaining a high marginal income from forage production, (ii) the probability of a high conservation value based on the occurrence of regionally rare plants, and (iii) carbon stocks in mineral soils (SOC). The predictions are based on 22 plant traits of 123 common species of reeds and of dry, mesic, wet, and ruderal grasslands. The individual traits were aggregated to trait modules representing major biological functions that affect the provision of services. High marginal income from forage production was predicted for plant communities functionally composed of intermediate levels of above-ground size and allocation, and an acquisitive leaf economy on the one hand, but little lateral expansion, generative reproduction and root mass on the other. The probability of finding regionally rare plants increased in communities with small-to-intermediate above-ground size, a conservative leaf economy, low C:N ratios, few and large seeds, and little lateral expansion. Communities displaying pronounced lateral expansion and above-ground size were linked to high soil organic-carbon stocks. The models predict trade-offs between these ES that are relevant to environmental planning. Where income from forage production is high, regionally rare plants will not be found, and SOC will be low. Where SOC is high, income from forage production will be low and rare plants infrequent. Where many rare plants are found, neither income from forage production nor SOC will be high. Using the predictive functions and the trait data provided in the Appendix S3, users can evaluate the supply of the three services for many perennial herbaceous communities in northwestern Europe.
Species' functional traits set the blueprint for pair-wise interactions in ecological networks. Yet, it is unknown to what extent the functional diversity of plant and animal communities controls ...network assembly along environmental gradients in real-world ecosystems. Here we address this question with a unique dataset of mutualistic bird-fruit, bird-flower and insect-flower interaction networks and associated functional traits of 200 plant and 282 animal species sampled along broad climate and land-use gradients on Mt. Kilimanjaro. We show that plant functional diversity is mainly limited by precipitation, while animal functional diversity is primarily limited by temperature. Furthermore, shifts in plant and animal functional diversity along the elevational gradient control the niche breadth and partitioning of the respective other trophic level. These findings reveal that climatic constraints on the functional diversity of either plants or animals determine the relative importance of bottom-up and top-down control in plant-animal interaction networks.
1. Ecological research produces a tremendous amount of data, but the diversity in scales and topics covered and the ways in which studies are carried out result in large numbers of small, ...idiosyncratic data sets using heterogeneous terminologies. Such heterogeneity can be attributed, in part, to a lack of standards for acquiring, organizing and describing data. Here, we propose a terminological resource, a Ṯhesaurus O̱f P̱lant characteristics (TOP), whose aim is to harmonize and formalize concepts for plant characteristics widely used in ecology. 2. TOP concentrates on two types of plant characteristics: traits and environmental associations. It builds on previous initiatives for several aspects: (i) characteristics are designed following the entity-quality (EQ) model (a characteristic is modelled as the 'Quality' of an 'Entity' ) used in the context of Open Biological Ontologies; (ii) whenever possible, the Entities and Qualities are taken from existing terminology standards, mainly the Plant Ontology (PO) and Phenotypic Quality Ontology (PATO) ontologies; and (iii) whenever a characteristic already has a definition, if appropriate, it is reused and referenced. The development of TOP, which complies with semantic web principles, was carried out through the involvement of experts from both the ecology and the semantics research communities. Regular updates of TOP are planned, based on community feedback and involvement. 3. TOP provides names, definitions, units, synonyms and related terms for about 850 plant characteristics. TOP is available online (www.top-thesaurus.org), and can be browsed using an alphabetical list of characteristics, a hierarchical tree of characteristics, a faceted and a free-text search, and through an Application Programming Interface. 4. Synthesis. Harmonizing definitions of concepts, as proposed by TOP, forms the basis for better integration of data across heterogeneous data sets and terminologies, thereby increasing the potential for data reuse. It also allows enhanced scientific synthesis. TOP therefore has the potential to improve research and communication not only within the field of ecology, but also in related fields with interest in plant functioning and distribution.
Land use and climate changes induce shifts in plant functional diversity and community structure, thereby modifying ecosystem processes. This is particularly true for litter decomposition, an ...essential process in the biogeochemical cycles of carbon and nutrients. In this study, we asked whether changes in functional traits of living leaves in response to changes in land use and climate were related to rates of litter potential decomposition, hereafter denoted litter decomposability, across a range of 10 contrasting sites. To disentangle the different control factors on litter decomposition, we conducted a microcosm experiment to determine the decomposability under standard conditions of litters collected in herbaceous communities from Europe and Israel. We tested how environmental factors (disturbance and climate) affected functional traits of living leaves and how these traits then modified litter quality and subsequent litter decomposability. Litter decomposability appeared proximately linked to initial litter quality, with particularly clear negative correlations with lignin-dependent indices (litter lignin concentration, lignin: nitrogen ratio, and fiber component). Litter quality was directly related to community-weighted mean traits. Lignin-dependent indices of litter quality were positively correlated with community-weighted mean leaf dry matter content (LDMC), and negatively correlated with community-weighted mean leaf nitrogen concentration (LNC). Consequently, litter decomposability was correlated negatively with community-weighted mean LDMC, and positively with community-weighted mean LNC. Environmental factors (disturbance and climate) influenced community-weighted mean traits. Plant communities experiencing less frequent or less intense disturbance exhibited higher community-weighted mean LDMC, and therefore higher litter lignin content and slower litter decomposability. LDMC therefore appears as a powerful marker of both changes in land use and of the pace of nutrient cycling across 10 contrasting sites.
Assessments of ecosystem services (ES), that aim at informing decisions on land management, are increasing in number around the globe. Despite selected success stories, evidence for ES information ...being used in decision making is weak, partly because ES assessments are found to fall short in targeting information needs by decision makers. To improve their applicability in practice, we compared existing concepts of ES assessments with focus on informing land use decisions and identified opportunities for enhancing the relevance of ES assessments for decision making. In a process of codesign, building on experience of four projects in Brazil, China, Madagascar, and Vietnam, we developed a step-wise approach for better targeting ES assessments toward information needs in land use decisions. Our problem-oriented approach aims at (1) structuring ES information according to land use problems identified by stakeholders, (2) targeting context-specific ES information needs by decision makers, and (3) assessing relevant management options. We demonstrate how our approach contributes to making ES assessments more policy relevant and enhances the application of ES assessments as a tool for decision support.
PDF
