Economics Traits Research Articles

Effects of climate, soil, and leaf traits on nutrient resorption efficiency and proficiency of different plant functional types across arid and semiarid regions of northwest China

BackgroundPlant nutrient resorption is crucial for the efficient conservation of nutrients. However, the mechanisms through which abiotic and biotic factors control nutrient resorption remain controversial. We investigated leaf nitrogen (N) and phosphorus (P) resorption efficiency (NRE and PRE) and resorption proficiency, as well as the underlying mechanisms for each plant functional type (PFT: non-legume herbs, non-legume shrubs, and legumes) by collecting green and senescent leaves of 59 species covering 106 sites from arid and semiarid regions of northwest China.ResultsLegumes had much lower leaf NRE and much higher senesced leaf N than the other two PFTs; they had similar leaf PRE to non-legume shrubs. Non-legume herbs exhibited the highest leaf P resorption. Climate, particularly temperature, increased leaf N resorption in non-legume herbs; however, climate, particularly decreasing precipitation, decreased leaf P resorption in legumes. Leaf nutrient resorption in non-legume shrubs decreased with increasing soil fertility, but leaf NRE in legumes increased. Leaf traits contributed more to leaf N and P resorption than climate and soil. Senesced leaf N and P concentrations increased along the resource-conservative to resource-acquisitive strategy axis. There were strong negative relationships between leaf NRE and senesced leaf N concentration and between leaf PRE and senesced leaf P concentration, in which legumes had a lower slope than non-legumes.ConclusionsThese findings suggest that ecological strategies and N-fixing plant types modulate nutrient resorption. Plants with the resource-conservative strategy are highly proficient in nutrient resorption. We highlight the importance of leaf economics traits and spectrum in regulating leaf nutrient resorption in drylands in the context of global climate change, potentially modulating plant traits and community composition. The higher proficient and efficient N and P resorption of plant species suggests the crucial importance of nutrient resorption in the nutrient cycling of harsh drylands.

A Trade-Off Between Leaf Carbon Economics and Plant Size Among Mangrove Species in Dongzhaigang, China.

Plant size is closely linked to its leaf trait characteristics, which are essential for determining its form and function. These relationships constitute a fundamental component of the global spectrum of plant diversity. Despite this, the size-trait relationships in coastal mangroves have often been overlooked, with a common assumption that they would mirror those found in terrestrial tropical trees. However, recent studies have begun to challenge this assumption, revealing unique adaptations and trait variations in mangroves that are influenced by their specific environmental conditions, such as salinity and nutrient availability. In this research, we investigated the leaf structural traits, plant height, and diameter at breast height or basal height (DBH) of 10 shrub and tree species. This study was carried out along an intertidal gradient within a mangrove forest located in Southeast China. We found that leaf traits differed significantly between shrubs and trees in their response to intertidal gradients, indicating that different species have evolved specific adaptations to thrive in their respective intertidal zones. This insight can help us decipher the selective pressures that have shaped trait evolution. Among all species, leaf carbon (C) economics (leaf dry mass content, leaf mass per area, and leaf density) decreased significantly with increasing plant height and DBH. For each growth form and intertidal zone, the relationships between plant size (height or DBH) and leaf C economics traits were consistent with those in the pooled dataset. Our study reveals that mangrove plants exhibit size-related adjustments in leaf C economic strategies, indicating that plant size potentially acts as a proxy for the "slow-fast" continuum of plant performance. This discovery is pivotal for advancing our understanding of plant functional ecology and for enhancing the precision of global C cycle models, which are highly responsive to perturbations in atmospheric CO2 and climate change.

Molecular-level carbon traits underlie the multidimensional fine root economics space.

Carbon influences the evolution and functioning of plants and their roots. Previous work examining a small number of commonly measured root traits has revealed a global multidimensionality of the resource economics traits in fine roots considering carbon as primary currency but without considering the diversity of carbon-related traits. To address this knowledge gap, we use data from 66 tree species from a tropical forest to illustrate that root economics space co-varies with a novel molecular-level traits space based on nuclear magnetic resonance. Thinner fine roots exhibit higher proportions of carbohydrates and lower diversity of molecular carbon than thicker roots. Mass-denser fine roots have more lignin and aromatic carbon compounds but less bioactive carbon compounds than lighter roots. Thus, the transition from thin to thick fine roots implies a shift in the root carbon economy from 'do-it-yourself' soil exploration to collaboration with mycorrhizal fungi, while the shift from light to dense fine roots emphasizes a shift from acquisitive to conservative root strategy. We reveal a previously undocumented role of molecular-level carbon traits that potentially undergird the multidimensional root economics space. This finding offers new molecular insight into the diversity of root form and function, which is fundamental to our understanding of plant evolution, species coexistence and adaptations to heterogeneous environments.

Variation in leaf carbon economics, energy balance, and heat tolerance traits highlights differing timescales of adaptation and acclimation.

Multivariate leaf trait correlations are hypothesized to originate from natural selection on carbon economics traits that control lifetime leaf carbon gain, and energy balance traits governing leaf temperatures, physiological rates, and heat injury. However, it is unclear whether macroevolution of leaf traits primarily reflects selection for lifetime carbon gain or energy balance, and whether photosynthetic heat tolerance is coordinated along these axes. To evaluate these hypotheses, we measured carbon economics, energy balance, and photosynthetic heat tolerance traits for 177 species (157 families) in a common garden that minimizes co-variation of taxa and climate. We observed wide variation in carbon economics, energy balance, and heat tolerance traits. Carbon economics and energy balance (but not heat tolerance) traits were phylogenetically structured, suggesting macroevolution of leaf mass per area and leaf dry matter content reflects selection on carbon gain rather than energy balance. Carbon economics and energy balance traits varied along a common axis orthogonal to heat tolerance traits. Our results highlight a fundamental mismatch in the timescales over which morphological and heat tolerance traits respond to environmental variation. Whereas carbon economics and energy balance traits are constrained by species' evolutionary histories, photosynthetic heat tolerance traits are not and can acclimate readily to leaf microclimates.

Contrasting coordination of non-structural carbohydrates with leaf and root economic strategies of alpine coniferous forests.

Non-structural carbohydrates (NSCs), as the labile fraction and dominant carbon currency, are essential mediators of plant adaptation to environments. However, whether and how NSC coordinates with plant economic strategy frameworks, particularly the well-recognized leaf economics spectrums (LES) and root economics space (RES), remains unclear. We examined the relationships between NSC and key plant economics traits in leaves and fine roots across 90 alpine coniferous populations on the Tibetan Plateau, China. We observed contrasting coordination of NSC with economics traits in leaves and roots. Leaf total NSC and soluble sugar aligned with the leaf economic spectrum, conveying a trade-off between growth and storage in leaves. However, NSC in roots was independent of the root economic spectrum, but highly coordinated with root foraging, with more starch and less sugar in forage-efficient, thinner roots. Further, NSC-trait coordination in leaves and roots was, respectively, driven by local temperature and precipitation. These findings highlight distinct roles of NSC in shaping the above- and belowground multidimensional economics trait space, and NSC-based carbon economics provides a mechanistic understanding of how plants adapt to heterogeneous habitats and respond to environmental changes.

Effects of Leaf Size and Defensive Traits on the Contribution of Soil Fauna to Litter Decomposition

Leaf litter quality has been acknowledged as a crucial determinant affecting litter decomposition on broad spatial scales. However, the extent of the contribution of soil fauna to litter decomposability remains largely uncertain. Nor are the effects of leaf size and defensive traits on soil fauna regulating litter decomposability clear when compared to economics traits. Here, we performed a meta-analysis of 81 published articles on litterbag experiments to quantitatively evaluate the response ratio of soil fauna to litter decomposition at the global level. Our results revealed that soil fauna significantly affected litter mass loss across diverse climates, ecosystems, soil types, litter species, and decomposition stages. We observed significantly positive correlations between the response ratio of soil fauna and leaf length, width, and area, whereas the concentrations of cellulose, hemicellulose, total phenols, and condensed tannins were negatively correlated. Regarding economic traits, the response ratio of soil fauna showed no relationship with carbon and nitrogen concentrations but exhibited positive associations with phosphorus concentration and specific leaf area. The mean annual temperature and precipitation, and their interactions were identified as significant moderators of the effects of soil fauna on litter decomposition. We evidenced that the contribution of soil fauna to litter decomposability is expected to be crucial under climate change, and that trait trade-off strategies should be considered in modulating litter decomposition by soil fauna.

Intraspecific leaf trait variation mediates edge effects on litter decomposition rate in fragmented forests.

There is strong trait dependence in species-level responses to environmental change and their cascading effects on ecosystem functioning. However, there is little understanding of whether intraspecific trait variation (ITV) can also be an important mechanism mediating environmental effects on ecosystem functioning. This is surprising, given that global change processes such as habitat fragmentation and the creation of forest edges drive strong trait shifts within species. On 20 islands in the Thousand Island Lake, China, we quantified intraspecific leaf trait shifts of a widely distributed shrub species, Vaccinium carlesii, in response to habitat fragmentation. Using a reciprocal transplant decomposition experiment between forest edge and interior on 11 islands with varying areas, we disentangled the relative effects of intraspecific leaf trait variation versus altered environmental conditions on leaf decomposition rates in forest fragments. We found strong intraspecific variation in leaf traits in response to edge effects, with a shift toward recalcitrant leaves with low specific leaf area and high leaf dry matter content from forest interior to the edge. Using structural equation modeling, we showed that such intraspecific leaf trait response to habitat fragmentation had translated into significant plant afterlife effects on leaf decomposition, leading to decreased leaf decomposition rates from the forest interior to the edge. Importantly, the effects of intraspecific leaf trait variation were additive to and stronger than the effects from local environmental changes due to edge effects and habitat loss. Our experiment provides the first quantitative study showing that intraspecific leaf trait response to edge effects is an important driver of the decrease in leaf decomposition rate in fragmented forests. By extending the trait-based response-effect framework toward the individual level, intraspecific variation in leaf economics traits can provide the missing functional link between environmental change and ecological processes. These findings suggest an important area for future research on incorporating ITV to understand and predict changes in ecosystem functioning in the context of global change.

Leaf habit and plant architecture integrate whole-plant economics and contextualize trait-climate associations within ecologically diverse genus Rhododendron.

Plant resource strategies negotiate a trade-off between fast growth and stress resistance, characterized by specific leaf area (SLA). How SLA relates to leaf structure and function or plant climate associations remains open for debate, and leaf habit and plant architecture may alter the costs versus benefits of individual traits. We used phylogenetic canonical correspondence analysis and phylogenetic least squares to understand the relationship of anatomy and gas exchange to published data on root, wood, architectural and leaf economics traits and climate. Leaf anatomy was structured by leaf habit and carbon to nitrogen ratio was a better predictor of gas exchange than SLA. We found significant correspondence of leaf anatomy with branch architecture and wood traits, gas exchange corresponded with climate, while leaf economics corresponded with climate, architecture, wood and root traits. Species from the most seasonal climates had the highest trait-climate correspondence, and different aspects of economics and anatomy reflected leaf carbon uptake versus water use. Our study using phylogenetic comparative methods including plant architecture and leaf habit provides insight into the mechanism of whole-plant functional coordination and contextualizes individual traits in relation to climate, demonstrating the evolutionary and ecological relevance of trait-trait correlations within a genus with high biodiversity.

Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America

Characterizing foliar trait variation in sun and shade leaves can provide insights into inter- and intra-species resource use strategies and plant response to environmental change. However, datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse, which limits our ability to investigate trait-trait, trait-environment relationships and trait coordination in both sun and shade leaves. We presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy, including 424 individuals of 110 plant species from 19 sites across eastern North America. We investigated trait variation, covariation, scaling relationships with leaf mass, and the effects of environment, canopy position, and taxonomy on trait expression. Generally, sun leaves had higher leaf mass per area, nonstructural carbohydrates and total phenolics, lower mass-based chlorophyll a + b, carotenoids, phosphorus, and potassium, but exhibited species-specific characteristics. Covariation between sun and shade leaf traits, and trait-environment relationships were overall consistent across species. The main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits, photosynthetic pigments, defense, and structural traits. Taxonomy and canopy position collectively explained most of the foliar trait variation. This study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem functions. Our findings have implications for efficient field sampling, and trait mapping with remote sensing.

Wood density and leaf size jointly predict woody plant growth rates across (but not within) species along a steep precipitation gradient

Abstract Functional traits have been proposed to define key dimensions of plant ecological strategies, but we lack consensus on whether traits can accurately predict plant demography. Despite theoretical expectations, it has been challenging to find consistent relationships between functional traits and growth. In this study, we quantified inter‐ and intraspecific trait variation (ITV) and individual growth rates of woody plants across a steep moisture gradient that varies 10‐fold in annual precipitation (350–3700 mm) in southern Chile and used a hierarchical Bayesian model to predict growth as a function of trait values. We show that large‐leaved species with lower stem tissue density exhibited the fastest growth rates, and these two traits exhibited the highest proportion of interspecific variation. Predictions of growth improved considerably (R2 of the best model increased from 0.28 to 0.49) when species‐level multiple traits and their interactions were considered. The inclusion of ITV, however, did not improve models of growth rate. We found that trait–growth rate relationships were not always consistent across levels of biological organization; relationships observed at the interspecific level did not necessarily hold at the intraspecific level. We found that the relationships between wood density or leaf size and growth were consistent in direction across the precipitation gradient, and the relationships between leaf economics traits and growth were weak and site‐specific. Synthesis. Although using more than one functional trait considerably improved growth predictions, wood density and leaf size successfully predicted growth rates across (not within) species, which is consistent with a whole‐plant carbon economy. We assert that these two traits are intimately linked and ultimately describe a continuum of plant architecture and carbon economy that covers multiple trait syndromes.

חייה וקיימא: סיוע הג'וינט לישיבות בישראל

From the very first years of the JDC's establishment, the organization supported Torah institutions. In 1920, it founded a designated cultural committee to coordinate activity which until the Holocaust, was religion-centric and devoted to Eastern Europe. However, from the 1950s onwards, most resources were directed to Israel. With the establishment of the State of Israel, the JDC believed that the responsibility for handling the yeshivas should be transferred to the Jewish Agency and the government. However, due to economic straits and the neglect of the state, the JDC continued to provide help to yeshivas and their students. The infrastructure and sanitary conditions of the post-Holocaust yeshivas in Eretz Israel were abysmal and visitors from the JDC became concerned about the nutrition and living conditions of students. The economic plan for Israeli yeshivas had been non-viable from the start, and as the number of yeshiva students increased, the institutions found it more and more difficult to provide them with the necessary resources. The situation necessitated renewed planning on the part of the JDC, and in 1954, the Cultural Committee decided to establish a special department to handle the yeshivas in Israel. The JDC did not see yeshivas merely as educational institutions but as communal organizations with social needs and as early as the 1940s, had supported their nutritional needs, constructed and renovated kitchens, purchased modern kitchen equipment, and provided them with guidelines regarding hygiene and food quality as well raw materials. The JDC likewise supported the introduction of occupational training programs for yeshiva students, thereby responding to their needs well-beyond the provision of financial support.

Soil water content and nitrogen differentially correlate with multidimensional leaf traits of two temperate broadleaf species

The variation and correlation of leaf economics and vein traits are crucial for predicting plant ecological strategies under different environmental changes. However, correlations between these two suites of traits and abiotic factors such as soil water and nitrogen content remain ambiguous. We measured leaf economics and vein traits as well as soil water and nitrogen content for two different shade-tolerant species (Betula platyphylla and Acer mono) in four mixed broadleaved-Korean pine (Pinus koraiensis) forests along a latitudinal gradient in Northeast China. We found that leaf economics traits and vein traits were decoupled in shade-intolerant species, Betula platphylla, but significantly coupled in a shade-tolerant species, A. mono. We found stronger correlations among leaf traits in the shade tolerant species than in the shade intolerant species. Furthermore, leaf economic traits were positively correlated with the soil water gradient for both species, whereas vein traits were positively correlated with soil water gradient for the shade intolerant species but negatively correlated in the shade tolerant species. Although economic traits were positively correlated with soil nitrogen gradient in shade intolerant species but not correlated in shade tolerant species, vein traits were negatively correlated with soil nitrogen gradient in shade tolerant species but not correlated in shade intolerant species. Our study provides evidence for distinct correlations between leaf economics and vein traits and local abiotic factors of species differing in light demands. We recommend that the ecological significance of shade tolerance be considered for species when evaluating ecosystem functions and predicting plant responses to environmental changes.

Using root economics traits to predict biotic plant soil-feedbacks

Plant-soil feedbacks have been recognised as playing a key role in a range of ecological processes, including succession, invasion, species coexistence and population dynamics. However, there is substantial variation between species in the strength of plant-soil feedbacks and predicting this variation remains challenging. Here, we propose an original concept to predict the outcome of plant-soil feedbacks. We hypothesize that plants with different combinations of root traits culture different proportions of pathogens and mutualists in their soils and that this contributes to differences in performance between home soils (cultured by conspecifics) versus away soils (cultured by heterospecifics). We use the recently described root economics space, which identifies two gradients in root traits. A conservation gradient distinguishes fast vs. slow species, and from growth defence theory we predict that these species culture different amounts of pathogens in their soils. A collaboration gradient distinguishes species that associate with mycorrhizae to outsource soil nutrient acquisition vs. those which use a “do it yourself” strategy and capture nutrients without relying strongly on mycorrhizae. We provide a framework, which predicts that the strength and direction of the biotic feedback between a pair of species is determined by the dissimilarity between them along each axis of the root economics space. We then use data from two case studies to show how to apply the framework, by analysing the response of plant-soil feedbacks to measures of distance and position along each axis and find some support for our predictions. Finally, we highlight further areas where our framework could be developed and propose study designs that would help to fill current research gaps.

Demographic trade-offs and functional shifts in a hurricane-impacted tropical forest.

Understanding shifts in the demographic and functional composition of forests after major natural disturbances has become increasingly relevant given the accelerating rates of climate change and elevated frequency of natural disturbances. Although plant demographic strategies are often described across a slow-fast continuum, severe and frequent disturbance events influencing demographic processes may alter the demographic trade-offs and the functional composition of forests. We examined demographic trade-offs and the shifts in functional traits in a hurricane-disturbed forest using long-term data from the Luquillo Forest Dynamics Plot (LFPD) in Puerto Rico. We analysed information on growth, survival, seed rain and seedling recruitment for 30 woody species in the LFDP. In addition, we compiled data on leaf, seed and wood functional traits that capture the main ecological strategies for plants. We used this information to identify the main axes of demographic variation for this forest community and evaluate shifts in community-weighted means for traits from 2000 to 2016. The previously identified growth-survival trade-off was not observed. Instead, we identified a fecundity-growth trade-off and an axis representing seedling-to-adult survival. Both axes formed dimensions independent of resprouting ability. Also, changes in tree species composition during the post-hurricane period reflected a directional shift from seedling and tree communities dominated by acquisitive towards conservative leaf economics traits and large seed mass. Wood specific gravity, however, did not show significant directional changes over time. Our study demonstrates that tree demographic strategies coping with frequent storms and hurricane disturbances deviate from strategies typically observed in undisturbed forests, yet the shifts in functional composition still conform to the expected changes from acquisitive to conservative resource-uptake strategies expected over succession. In the face of increased rates of natural and anthropogenic disturbance in tropical regions, our results anticipate shifts in species demographic trade-offs and different functional dimensions.

Convergent relationships between flower economics and hydraulic traits across aquatic and terrestrial herbaceous plants

Maintaining open flowers is critical for successful pollination and depends on long-term water and carbon balance. Yet the relationship between how flower hydraulic traits are coordinated in different habitats is poorly understood. Here, we hypothesize that the coordination and trade-offs between floral hydraulics and economics traits are independent of environmental conditions. To test this hypothesis, we investigated a total of 27 flower economics and hydraulic traits in six aquatic and six terrestrial herbaceous species grown in a tropical botanical garden. We found that although there were a few significant differences, most flower hydraulics and economics traits did not differ significantly between aquatic and terrestrial herbaceous plants. Both flower mass per area and floral longevity were significantly positively correlated with the time required for drying full-hydrated flowers to 70% relative water content. Flower dry matter content was strongly and positively related to drought tolerance of the flowers as indicated by flower water potential at the turgor loss point. In addition, there was a trade-off between hydraulic efficiency and the construction cost of a flower across species. Our results show that flowers of aquatic and terrestrial plants follow the same economics spectrum pattern. These results suggest a convergent flower economics design across terrestrial and aquatic plants, providing new insights into the mechanisms by which floral organs adapt to aquatic and terrestrial habitats.

Predicting ecosystem productivity based on plant community traits.

With the rapid accumulation of plant trait data, major opportunities have arisen for the integration of these data into predicting ecosystem primary productivity across a range of spatial extents. Traditionally, traits have been used to explain physiological productivity at cell, organ, or plant scales, but scaling up to the ecosystem scale has remained challenging. Here, we show the need to combine measures of community-level traits and environmental factors to predict ecosystem productivity at landscape or biogeographic scales. We show how theory can extend the production ecology equation to enormous potential for integrating traits into ecological models that estimate productivity-related ecosystem functions across ecological scales and to anticipate the response of terrestrial ecosystems to global change.

Comprehensive description of body shapes, sizes and plumage colorations of domestic pigeons in Benue State of Nigeria

The domestic Pigeons (Columbia livia domestica) are hardy birds that can be raised with little effort. They are able to survive in hostile climates and fend for themselves, often ranging over many kilometers in attempt to locate seeds and edible scraps. In Nigeria pigeons are well distributed in the different agro-ecological zones of the country. In Benue State and indeed Nigeria, the available domestic pigeon population is largely genetically and phenotypically uncharacterized. Considering this fact, the present study was conducted on Comprehensive Description of Body Shapes, Sizes and Plumage Colorations of Domestic Pigeons in Benue State, Nigeria. Field data collection phase of the study was carried out through combined use of questionnaire and fortnightly visits for a period of six months. A total of sixty pigeon farmers and three hundred domestic pigeons were covered during the survey. Mature body weights were measured to the nearest grammes on all the adult birds covered during the field data phase using a 5kg capacity weighing scale. Plumage, beak and shank colourations/colour patterns were measured via visual observations during the two phases of the experiment. Body, shank, beak, thigh and wing lengths and breast girth were measured at maturity using a graduated linear scale (rule) and tailor’s tape. Bird height (from leg on the ground up to the level of the back of the bird) was also measured. Qualitative data collected were subjected to descriptive statistics such as percentages and averages, while the data quantitative (economics) traits were analyzed through the use of Analysis of Variance (ANOVA) technique and correlation analysis based on the SPSS II programme. Ash plumage predominated other colours, constituting 16.94% of all the observed plumage colours. This was closely followed by brown (12.78%), black (12.22%) and white (12.22%) with black and grey colour being the rarely observed (1.39%). About 56% of the pigeons surveyed had muffed feet (feathered feet). The overall mean weight of 326.63±1.69 for male and 312.25±1.83 for female pigeons kept on semi-intensive system is slightly lower. In terms of morphological traits, the pigeons demonstrated a great deal of variations and complexities in plumage, shank and beak colourations. The variations observed in other quantitative traits such as linear body measurements (body, shank and beak lengths breast girth and bird height) revealed no significant difference ((P>0.05).

Socio-economic characteristics of pigeon farmers in Benue State of Nigeria

In Nigeria pigeons are well distributed in the different agro-ecological zones of the country. Their widespread distribution in the urban and rural areas demonstrates the socio-economic and cultural importance of these small and easily managed birds. Pigeon production may never rise enough to compete with commercial poultry as a major source of food, but for the poor farmers and some urban dwellers, these birds could become a significant addition to their diet (as per animal protein intake) as well as a source of substantial supplemental income. It is therefore imperative to study the socio-economic characteristics of pigeon farmers in the study area. Three Local Government Areas namely Okpokwu (Ugbokolo), Katsina-Ala, and Vandeikya were chosen for the study. A total of sixty (60) pigeon farmers and three hundred (300) domestic pigeons were covered during the survey. Qualitative data collected were subjected to descriptive statistics such as percentages and averages, while the data quantitative (economics) traits were analyzed through the use of Analysis of Variance (ANOVA) technique and correlation analysis based on the SPSS II programme. The data showed that men were more involved in domestic pigeon production (87.77%) than women (12.23%). Students constituted the majority involved in domestic pigeon production (38.89%) followed by food crop producers (32.22%) and farmers/traders being in the least (5.56%). The major crops cultivated were yam (30.00%), cassava (15.67%), rice (13.67%), maize (11.67%) respectively. It was recommended that Proper housing for domestic pigeons should be adopted by pigeon farmers.

Venus Betrayed: The Private World of Édouard Vuillard by Julia Frey

Reviewed by: Venus Betrayed: The Private World of Édouard Vuillard by Julia Frey Stephanie Rauschenbusch (bio) venus betrayed: the private world of Édouard vuillard Julia Frey Reaktion Books http://www.reaktionbooks.co.uk/display.asp?ISB=9781789141603 424 pages; Cloth, $42.09 Julia Frey, biographer of Toulouse-Latrec, has written a biography of Édouard Vuillard that begins with her explanation of her own amazement at his work: I was around twenty when I first saw art by Édouard Vuillard (1868–1940). … I felt summoned, magnetized by their (the art works') subtly constructed beauty. They seemed nearly abstract, composed with conflicting proportions and perspectives and using wildly contrasting patterns: flowered wallpaper; striped upholstery; draperies; tapestries; tile work. … As I came close, I realized that these canvases nearly always included figures who blended so seamlessly into the background as to be nearly invisible. Most often they were women, dressed in marvellous, complicated fabrics; cloth with symbolic impact. Vuillard wraps his women in climbing vines, barricades them behind brick walls or makes them into femmes fleurs. Each chapter is a separate investigation into Vuillard's life and relationships, and each chapter reads like the chapter of a novel. First we learn of Vuillard's family at dinner, and the discussion surrounds an 1889 painting reproduced in color, which Frey characterizes as "like a puppet-show maquette. … This is not surprising, since Vuillard worked with experimental puppet theatres for several years about this time." She goes on to liken the figures to the three witches in Macbeth and describes their rite as "involving a match, a tiny candle, a huge bottle of wine, a table with no food, and a baguette as big as a [End Page 166] truncheon." This is indeed a totally strange painting in which only the mother is fully visible wearing black and silhouetted against golden candlelight. The other figures are either totally veiled (the grandmother) or standing uncertainly in the doorway. Using Vuillard's sketchbooks, Frey finds five images that seem to supply the key to this mysterious event. The biographical explanation for the painting follows: After his father's death in 1884, the family, in economic straits, was almost entirely dependent on Madame Vuillard's cottage industry as a corset-maker, which she ran from their dining room. Édouard, the youngest child,—then fifteen—fell into the first of what became a repetitive, frightening depression. A typical adolescent, he dealt with misery by slipping out secretly, pursuing forbidden pleasures. So Vuillard paints his home as a sort of trap, in which he and his older sister are squashed into the very wallpaper by the dominance of their mother. One of Vuillard's most amazing oils is set in the dining room as a confrontation between mother and sister, in which the sister bends almost in half as she seems to disappear into the wall. Frey points out that Vuillard used this vivid and visually variegated home studio, where the corsets were made and young girls were employed as seamstresses, as his theater, and the seamstresses and his mother and sister as characters in a perpetual play in which he controlled the movements of each one. He himself is often just a pair of black eyes, staring in an otherwise anonymous face. He huddles in doorways, eats non-existent meals, tries to be the only male present, since his father died when Édouard was fifteen. He himself has no thought of becoming a naval officer like his father, but like his friends from school, he attends art classes and begins to paint his own scenes. Frey takes a chapter to discuss Vuillard's arrangement with his grandmother, whose private bedroom is allowed to be his studio. He paints her often, in her widow's weeds, against the brilliant light from her window, likened to that of Tachiste paintings. She had her daughter before she was married and is somehow always tarred by this brush of the daughter's (Vuillard's mother's) illegitimacy. Vuillard's mother is also seen as cramped by this opprobrium. Another chapter covers the men of Vuillard's family—his pathetic, wounded [End Page 167] father, his disappointed brother, retired from the military, who also...

How detritivores, plant traits and time modulate coupling of leaf versus woody litter decomposition rates across species

Abstract Plant functional traits are increasingly used to understand ecological relationships and (changing) ecosystem functions. For understanding ecosystem‐level biogeochemistry, we need to understand how (much) traits co‐vary between different plant organs across species and its implications for litter decomposition. However, we do not know how the degree of synchronous variation in decomposition rates between organs across species could be influenced by different keystone invertebrates decomposing different senesced plant organs, especially in warm‐climate forests. Here we asked whether interspecific patterns in wood and leaf decomposition rates and in the spectra of resource economics traits underpinning them, co‐vary across woody species; and how (much) the keystone invertebrate decomposers of the litter of these organs enhance or lower such co‐variation of decomposition rates through time. We addressed these questions through an 18‐month ‘common‐garden’ decomposition experiment using leaf, twig and branch litter of 41 woody species in two distant subtropical forest sites in east China. We quantified the effects of leaf, twig and branch functional traits and their respective key invertebrates (moth larvae, termites) on the decomposition rates of those organs. Interspecific variation in wood traits was partly decoupled from that in leaf traits across species, while strong coupling was found between twigs and branches. The co‐variation between leaf and woody organ decomposition rates was altered dynamically through the shifting activities of the key decomposers, which created nonlinear relationships of invertebrate litter consumption as a function of species rankings along the resource economic trait spectra of leaves and branches. The deviations from coupling of decomposition rates between organs were likely caused by combinations of three mechanisms: (1) (de‐)coupling between organs of other traits, not commonly considered in resource economics spectra (e.g. resins) (2) leaf and wood decomposers having specific diet requirements and (3) temporal patterns of the decomposers' activity. Synthesis. Our study highlights the importance of considering the different ways by which invertebrate detritivores drive decomposition processes through time. Under the ongoing biodiversity decline, future research would benefit from a better understanding of the role of the dynamic interactions between detritivore activities and plant functional traits on the carbon turnover in ecosystems.