Littérature scientifique sur le sujet « Bio-Ecological trait »

The largest part of forest biomass consists of wood. A global estimate of carbon stored in lignified tissues rises up to 400 Pg. Given these quantities, there is a growing interest of implementing wood research in diagnoses and evaluations of the carrying capacity of the global ecosystem and its forests. The question arises how disciplines like wood anatomy could respond to the increasing demands of a trait-based ecology, understood as a paradigmatic shift in addressing global changes. Dendrochronology and ecological wood anatomy, traditionally operating within the paradigm of species-based ecology, developed robust methods to address ecological questions. However, sampling strategies and database design will likely be different when wood traits are to be used to study individual tree performance, including responses to stress.Aiming at optimally involving wood research in trait-based ecology, some trait concepts are analysed. The value of the IAWA standard lists of wood anatomical features as starting points for trait databases is recognized. A summary of the functionality of wood is given to inform the trait-research community of basic aspects of tree performance. The time dimension is highlighted, as well as the foundations for understanding bio-hydraulics, bio-mechanics and metabolism of wood and relevant traits.Guidelines are given for sampling strategies and database concepts. Prospects of time axis construction and system integration are discussed, as well as the importance of standardizing for size.

Abstract. Stemflow transports nutrient-enriched precipitation to the rhizosphere and functions as an efficient terrestrial flux in water-stressed ecosystems. However, its ecological significance has generally been underestimated because it is relatively limited in amount, and the biotic mechanisms that affect it have not been thoroughly studied at the leaf scale. This study was conducted during the 2014 and 2015 rainy seasons at the northern Loess Plateau of China. We measured the branch stemflow volume (SFb), shrub stemflow equivalent water depth (SFd), stemflow percentage of incident precipitation (SF %), stemflow productivity (SFP), funnelling ratio (FR), the meteorological characteristics and the plant traits of branches and leaves of C. korshinskii and S. psammophila. This study evaluated stemflow efficiency for the first time with the combined results of SFP and FR, and sought to determine the inter- and intra-specific differences of stemflow yield and efficiency between the two species, as well as the specific bio-/abiotic mechanisms that affected stemflow. The results indicated that C. korshinskii had a greater stemflow yield and efficiency at all precipitation levels than that of S. psammophila. The largest inter-specific difference generally occurred at the 5–10 mm branches during rains of ≤ 2 mm. Precipitation amount was the most influential meteorological characteristic that affected stemflow yield and efficiency in these two endemic shrub species. Branch angle was the most influential plant trait on FR. For SFb, stem biomass and leaf biomass were the most influential plant traits for C. korshinskii and S. psammophila, respectively. For SFP of these two shrub species, leaf traits (the individual leaf area) and branch traits (branch size and biomass allocation pattern) had a great influence during lighter rains ≤ 10 mm and heavier rains > 15 mm, respectively. The lower precipitation threshold to start stemflow allowed C. korshinskii (0.9 mm vs. 2.1 mm for S. psammophila) to employ more rains to harvest water via stemflow. The beneficial leaf traits (e.g., leaf shape, arrangement, area, amount) might partly explain the greater stemflow production of C. korshinskii. Comparison of SFb between the foliated and manually defoliated shrubs during the 2015 rainy season indicated that the newly exposed branch surface at the defoliated period and the resulting rainfall intercepting effects might be an important mechanism affecting stemflow in the dormant season.

The present investigation was conducted to study the impact of bio-inoculants under low input field conditions on the magnitude and direction of gene effects and the mean performance of nitrogen (N) and phosphorus (P) use in wheat. Three wheat cultivars suitable for different agro-ecological conditions, i.e. WH 147 (low mineral input), WH 533 (water deficit), Raj 3077 (high mineral input), and six generations (P 1 , P 2 , F 1 , F 2 , BC 1 and BC 2 ) of three crosses, namely WH 147 × WH 533, WH 533 × Raj 3077 and WH 147 × Raj 3077, were evaluated in a randomized block design with three replications under low input field conditions (80 kg N + 40 kg P + 18 kg ZnSO 4 doses applied in each treatment) with three treatments, i.e. control, inoculation with arbuscular mycorrhiza fungi (AMF, Glomus fasciculatum ) and dual inoculation with AMF and Azotobacter chroococcum ( Azc ). Bioinoculation with AMF and AMF+ Azc had a positive impact on the mean performance of all the wheat crosses. The mean performance of AMF was maximum in the cross WH 147 × WH 533 for N and P response (%), N and P use index (%) and P content (ppm), whereas for N and P uptake it was maximum in the cross WH 147 × Raj 3077. The response and use index for N and P were better in the combined AMF+ Azc treatment in all three crosses. The adequacy of the additive-dominance model for the phosphorus uptake (mg/plant) by all three crosses in all three treatments (i.e. control, AMF, AMF+ Azc ) suggested that additive (d) and dominance (h) gene effects mainly governed the inheritance of this trait. In all cases, digenic interactions were present, where the duplicate type of epistasis prevailed except for the P content in the control in the cross WH 147 × WH 533, where the complementary type of interaction was present. Pedigree selection in crosses WH 147 × WH 533 and WH 147 × Raj 3077 could be effective for breeding pure lines of wheat for sustainable agriculture (low input genotypes responsive to biofertilizers such as AMF and Azotobacter ).

Abdelhady AA, Abdalla MM. 2018. Short Communication: Categorization models as a powerful tool in paleontological data analyses – the Phanerozoic bivalves. Biodiversitas 19: 1769-1776. Predicting biotic responses to current and future global change can be acquired through understanding how biological and environmental traits shaped the past origination, dispersion and extinction patterns. A global dataset encompasses 161,357 taxon occurrences belonging to 2,378 bivalve genera from past and recent environments were analyzed based on the categorization model, a widely-used machine-learning analysis, using MS-SQL and Excel PowerView. The occurrence data was standardized using square-root transformation to downplay the effect of sampling effort. Thus, the examined traits are resulting from reliable ecological interactions. The results indicate that the biotic traits of the bivalve can be determined by the abiotic ones. Moreover, ecological traits such as life habit (i.e., infaunal vs. epifaunal), diet (suspension vs. deposit feeders, herbivores vs. carnivores), composition (aragonite vs. calcite), and locomotion (stationary vs. mobile) all exhibit significant relation to a specific environment. The results demonstrated that decision tree and association rules are primary powerful tools in analyzing huge biological data and in testing many useful bio-ecological hypotheses.

Context: Compare the effect of different ecological conditions on phenotypical traits of Phlomis olivieri.Objective: To observe morphological variation between and within different populations of Phlomis olivieri Benth.Materials and Methods: Morphological characters of eleven populations of Phlomis olivieri were investigated in the both levels: between and within populations. Samples were collected from different parts of Iran and from each population, 3 to 4 samples were elected randomly and sixteen quantitative and qualitative morphological traits from the both vegetative and reproductive organs were examined.Results: Analysis of variance test as well as one-sample test confirmed significant variations for quantitative morphological traits. Morphological features varied between populations, consequently populations were separated from each other in the UPGMA tree and also PCO and PCA plots, among these, populations K, A, D and B placed far from others. Some degrees of polymorphism in morphological traits occurred within populations and individuals of each stand separated from others.Conclusion: This study showed that ecological factors had strong effect on morphological features of different populations of same plant species. This phenomenon was called phenotypic plasticity which created infraspecific variations at both levels interpopulation and intrapopulation or morphological polymorphism among populations.J. bio-sci. 22: 59-67, 2014

In the April of 2007, pseudomyiasis was detected in alimentary tract of two years old boy from South Moravia (Czech Republic). Contamination was caused by larvae of family Calliphoridae (Diptera), accidentally consummated with half-rotten fruits from bio compost. It is the first recent documented case of pseudomyiasis, and is closely connected with bio waste and ecological waste disposal. Usage of organic waste composting is increasing all around the world, motivated by demand for maximum recycling. While workrooms of bigger compost facilities are usually separated from public, waste containers in front of the houses or small composts in the gardens serving one family are freely accessible to public. These bio composts and waste containers attract many species of insects, especially from order Diptera. so for inhabitants of neighbouring houses this can represent certain health risk. In the location of findings, Dipteras were caught and their species spectrum was evaluated considering their ability to cause myiases or pseudomyiases.

The paper presents some preliminary results of the monitoring of Fritillaria meleagroides Partin ex Schult. et Schult. fil. and Tulipa biebersteiniana Schult. et Schult. fil. plants (category of rare and endangered plant species). The results of the field study fulfilled in 2012-2016 in two population groups of quarter 80 and cenopopulation of quarter 69 in the Krasnosamarsky forestry (Samara Region) were used to determine morphometric parameters of plant species. The data also helped us to assess the variability level and to make a comparison with plant quantitative traits given in the literature. It has been found that the sample indicators fit into the range of values specified in literature sources, with a significant proportion of large fruit 2,0-3,0 cm in length. The dynamics of the fruit size of Fritillaria meleagroides Partin ex Schult. et Schult. fil. and Tulipa biebersteiniana Schult. et Schult. fil. plants in population groups of quarter 80, as a whole, has general patterns in the difference during some seasons of vegetation. Prevailing values of fruit length of plants in cenopopulations of quarter 69 changed slightly according to year of vegetation, these populations are more resistant and numerous comparing with the populations of quarter 80. As for variability of signs, the values of fruit length and width coefficients of variation does not exceed 25% for Fritillaria meleagroides Partin ex Schult. et Schult. fil. plants and 20% for Tulipa biebersteiniana Schult. et Schult. fil. plants which is optimal for this type of indicators and is consistent with the bioecological specificity of fruit plant. The conditions of ecosystems in 69 and 80 quarters of Krasnosamarsky forestry are favorable for the vegetation of two species plants, the successful preservation and restoration in natural communities can be in the absence of anthropogenic factors limits.

The level of alteration in response to the same level of exposure can vary greatly among different ecosystems: in particular, effects provoked by chemicals are not only relying on their “absolute toxicity” and on their concentration, but also on the ecological vulnerability of the system. Vulnerability is often overlooked in current risk assessment procedure, but its knowledge is pivotal in site-specific studies, where the object of the protection is shifted from a generic scenario to a real ecological system. The study of ecological vulnerability confirms that risk assessment, as becoming site-specific, needs more ecological knowledge. In this path, the use of ecological and biological traits of organisms has proven to be a promising approach to evaluate the ecological vulnerability at different level of biological organization. In this work the issue of the ecological vulnerability has been considered from several different perspectives, using multiples methodologies and working at completely different scales. The leading thread is to show how an ecologically based approach can enhance our understanding of environmental processes and thus improving risk assessment methodologies.

Un’approfondita conoscenza circa le risposte delle popolazioni selvatiche ai cambiamenti ambientali e climatici rappresenta un obiettivo primario per migliorare le politiche ambientali e promuovere la conservazione della biodiversità. La capacità di una popolazione nel rispondere ai cambiamenti che avvengono negli ecosistemi è uno dei principali fattori che può determinare la sua traiettoria nel tempo e nello spazio. La presente tesi illustra, sia da un punto di vista metodologico che applicativo, quattro studi che analizzano alcuni tipi di risposte a lungo termine delle popolazioni di uccelli, fornendo nuovi e significativi risultati in una prospettiva ecologica di ampio respiro. Il primo lavoro si è focalizzato su aspetti metodologici che riguardano la modellizzazione dei trend di popolazione al fine di fornire un utile contributo per migliorare i processi di stima. Proponendo un approccio a step multipli, il lavoro ha investigato gli effetti dell’environmental bias, causato da variazioni avvenute nello sforzo o nel disegno di campionamento nello spazio e nel tempo, e di due proprietà statistiche dei dati di conteggio, cioè overdispersion e zero inflation, sul processo di stima. I risultati hanno evidenziato che l’environmental bias è il fattore principale nel determinare differenze tra i trend stimati dai diversi modelli. In aggiunta, l’overdispersion e la zero inflation sono in grado di influenzare, anche in modo significativo, le stime, perciò devono essere tenuti in considerazione nell’approccio statistico. Nel secondo lavoro, tale proposta modellistica è stata impiegata per stimare i trend di popolazione a lungo termine per gli uccelli nidificanti in nord Italia. Inoltre, attraverso un trait-based approach, è stato investigato se specie con analoghe caratteristiche life-history ed ecologiche (traits) condividessero simili dinamiche di popolazione. I risultati hanno identificato le specie che richiedono maggiore attenzione di conservazione e per le quali sono necessarie misure di gestione per evitare ulteriori declini di popolazione in futuro. Il trait-based approach ha individuato i gruppi ecologici e funzionali sottoposti a maggiori pressioni, enfatizzando l’utilità delle informazioni dei traits in un’ottica di conservazione. Il terzo lavoro presenta un caso studio in cui si è investigata la capacità delle specie, di adattare, lungo periodi di tempo relativamente lunghi, la propria nicchia Grinnelliana realizzata come risposta ai cambiamenti ambientali. Inoltre, si è valutato se i cambiamenti di nicchia fossero collegati ai trend di popolazione, ottenuti dal precedente lavoro, e ai traits delle specie. L’analisi ha evidenziato che la conservazione della nicchia non è una condizione ubiquitaria, e alcune specie la stanno anzi modificando. In aggiunta, si è dimostrata un’associazione non casuale tra i cambiamenti di nicchia e i trend di popolazione, così come una relazione tra i cambiamenti di nicchia e i gruppi ecologici e funzionali. L’ultima ricerca ha investigato gli effetti di eventi climatici estremi, il cui crescente aumento di frequenza e intensità pone nuove sfide per la conservazione della biodiversità. Usando il programma di censimento a lungo termine degli uccelli nidificanti nel Regno Unito (UK BBS), e attraverso un’analisi condotta su specie multiple, si è studiato l’effetto degli eventi estremi e sono state identificate le specie con maggiore sensibilità nelle risposte. I risultati hanno evidenziato ampi effetti degli eventi climatici estremi sull’abbondanza delle popolazioni, suggerendo che essi potrebbero rappresentare un fattore chiave nel plasmare le future dinamiche di popolazione. I dati a lungo termine si sono rivelati essere di estrema importanza per valutare le risposte delle popolazioni ai cambiamenti ambientali, e sono essenziali per arrivare ad una comprensione esaustiva dei processi ecologici che possono influenzare le biocenosi e gli ecosistemi.
An extensive knowledge about population responses to ongoing environmental and climatic changes is a primary goal to enhance environmental policies and promote biodiversity conservation. The capacity of a population in responding to rapid changes occurring within ecosystems is one of the most important aspects that can determine its trajectory over space and time. This thesis describes four studies that analyse some long-term responses of bird populations from both a methodological and applicative point of view, providing novel and valuable findings not only for bird studies but also in a broad ecological perspective. The first research focused on some methodological issues in population trend modelling. Changes in population size over time (i.e. population trends) are one of the clearest responses of populations to environmental changes and represent a key tool for wildlife conservation. Thus, improving the capacity of estimating trends is pivotal. The study investigated the effects of the environmental bias, which may affect many existing surveys because of a variation in the sampling effort or design over space and time, and of two statistical properties of count data, namely overdispersion and zero inflation, on the estimation process of population trends. A multi-step modelling approach was proposed, and findings highlighted that the environmental bias was the most important factor that causes differences in trend estimates across models. Additionally, overdispersion and zero inflation can influence, also significantly, the estimates, and modelling frameworks should consider their evaluation in the statistical approach. In the second work, this modelling framework was applied to assess the long-term population trends for common breeding birds at regional scale (northern Italy). Additionally, through a trait-based approach, the study investigated whether species with similar life-history and ecological traits shared similar population dynamics. Findings allowed identifying species that need more conservation attention and for which management measures are required to avoid further population declines. The trait-based approach allowed identifying which ecological and functional groups need greater attention, emphasising the usefulness of traits’ information to plan further studies aimed at identifying the drivers at the basis of the observed population changes. Then, the third study focused on niche modelling to understand whether a species can adapt its realised Grinnellian niche along relatively long-term periods as results of ongoing environmental changes. Moreover, the study assessed whether the observed changes were linked to population trends, obtained from the previous work, and to species traits. The multi-species analysis on common breeding birds highlighted that niche conservatism is not a ubiquitous condition, and some species are changing their niches. Findings also showed the existence of non-random associations between niche changes and both population trends and groups of species sharing similar life-history and ecological traits. The last research dealt with assessing the effects of climate change on bird populations focusing on the extreme climatic events, which exacerbation and increase in frequency poses new global challenges for nature conservation. Using the UK Breeding Bird Survey, a long-term large-scale monitoring program, a multi-species analysis investigated how populations respond to extreme climatic events and which species are more sensitive to such climatic conditions. Findings highlighted widespread effects of extreme climatic events on the abundance of bird populations, suggesting that they could be a key driver for shaping future population dynamics. Long-term data revealed to be extremely important for assessing responses of populations in a changing environment and are essential to achieve a comprehensive perspective of ecological processes that can affect biocenoses and ecosystems.