TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

TRY plant trait database - enhanced coverage and open access

Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Improving rheological and mechanical properties of non-plastic clay soil from Bensmim region (Morocco) using bentonite additions: Suitability for building application

The present study aims to develop an innovative scientific methodology for adjusting the phys-icochemical composition of any clay soil to make it appropriate for construction applications. The realized research was carried out on unexploited clayey soil extracted from Bensmim village (Morocco). Another clay sample from "Extrabrick" brick manufactory was also used as a reference since it is used to produce high-quality bricks. Raw materials physicochemical and geotechnical properties were determined. Results demonstrated that the studied clay is an unsuitable raw material for clay bricks production. This is due to its low plasticity resulting from its significant sand content, low clay fraction, and absence of swelling clay. Therefore, improving the plasticity of our clay was taken as a critical factor to enhance the properties of this clay. Different per-centages of bentonite, which is known for its high plasticity, ranging from 0 to 10%, were added to study the effect of this addition on the characteristics of the studied clay. The rheological and mechanical analysis showed that increasing the percentage of bentonite has a beneficial effect on the properties of the studied clay bricks. In fact, the addition of 10% bentonite showed an increase in the yield stress, viscosity, and the mixture exhibited a rheological behavior very close to the reference sample. The founded results were fitted to Herschel-Bulkley classical. The findings suggest that the addition of bentonite decreases the flow index value and increases the consis-tency index of the studied clay. Furthermore, compressive strength went from 5.3 MPa for the studied clay without additive to 19.33 MPa after 10% of bentonite addition. This value of compressive strength is very close to the compressive strength of the reference brick 23.83 MPa. These results confirmed that rheology could be a powerful tool to tune the formulation of con-struction materials

Physico-chemical, mineralogical, and technological characterization of stabilized clay bricks for restoration of Kasbah Ait Benhadou- Ouarzazate (south-east of Morocco)

3rd International Congress on Materials and Structural Stability (CMSS), Rabat, MOROCCO, NOV 24-26, 2021International audienceDue to ageing, the unfired brick masonry may detach and fall off, or deteriorate to such an extent that it becomes necessary to restore them. Such is the case, for instance, of the Ksar of Ait Benhadou in Ouarzazate, Morocco. Our study aims to provide compatible and sustainable earthen bricks to restore this monument. Samples were collected from facades that were under conservation/restoration at the time when sampling was performed. Clayey soil samples were collected vicinity to the Ksar and analyzed by X-ray diffraction and X-ray fluorescence. A representative sample was stabilized with three aggregates (lime, cement and straw). The effect of ageing of the stabilized briquettes on shrinkage, water absorption, mechanical and thermal properties, compressive strength and thermal conductivity was studied on stabilized specimens. The samples consist mainly of clay minerals, calcite and quartz. They are rich in iron, aluminium and potassium. These samples are sandy with low plasticity (PI = 7%), which is slightly lower than the plasticity value required by the Moroccan standard for earth constructions. The results showed that the stabilized clayey soils have suitable properties such as density, porosity, water absorption and high thermal insulation. The best compressive strength performance is obtained for clay-stabilized samples with a high sand fraction. The thermal conductivity of clay-stabilized specimens increases as the specimens become denser and more compact, lime and straw have the opposite effect. Copyright (C) 2022 Elsevier Ltd. All rights reserved

Tracking the Ti4+ substitution in phlogopite by spectroscopic imaging: A tool for unravelling the growth of micas at HP-HT conditions

Phlogopite solid-solutions have a wide pressure-temperature (P-T) stability field and are ubiquitous in a wide variety of geological settings, from deep lithosphere magmatic environments to upper crust metamorphic domains. Phlogopite composition represents therefore a valuable physical-chemical archive and may provide important information regarding its crystallization and the petrogenesis of the host-rock. In this paper we examine the phlogopite phenocrysts from the well-known Fort Regent mica-bearing lamprophyre minette from St. Helier (Island of Jersey, UK). Phlogopite phenocrystals from lamprophyres generally show normal -step and continuous compositional zoning, however those from the Fort Regent minette show a peculiar texture characterized by dark brown high-Ti (average TiO2 ⠁ 8.5 wt.%) cores enveloped by euhedral low- to mid-amplitude zonation due to oscillatory contents in Ti, Fe and Mg. Thermo-barometry modelling based on biotite-only composition yields relatively high P-T estimates (T ⠁ 970 +/- 54 degrees C at P ⠁ 0.73 +/- 0.13 GPa) for cores whereas lower values (T ⠁ 790 +/- 54 degrees C at P ⠁ 0.29 +/- 0.13 GPa) are obtained for the outer rims. Comparable temperatures (T ⠁ 1075 +/- 54 degrees C) but extremely high and anomalous pressure values (P ⠁ 1.82 +/- 0.13 GPa) are obtained for the yellowish inner rims. The combination of electron micro probe (EMP) analysis and single-crystal infra -red (FTIR) imaging in the OH-stretching region shows that the exceptional and oscillatory Ti contents are due to the Ti-vacancy substitution, typical of crystallization and growth processes of HP/HT environments. Raman imaging provides additional insight for this process, confirming the dominant dioctahedral nature for the Ti-Fe-rich cores and outer rims. Interpretation of thermobaric estimates obtained from the phlogopite compositiononly model, based on the fine-scale compositional evolution, shows that pressure-temperature values from low-Ti high-Mg domains should be carefully evaluated because the substitution mechanisms during the dark mica growth are not univocally related to pressure-temperature variation of the crystallizing environment. Our results demonstrate how a multidisciplinary approach based on the combination of chemical investigations and vibrational spectroscopies could represent a valuable tool to evaluate pressure-temperature estimates from biotite composition-only thermo-barometry models and therefore to correctly unravel HP/HT petrogenetic processes at a very fine scale. (c) 2024 China University of Geosciences (Beijing) and Peking University. Published by Elsevier B.V. on behalf of China University of Geosciences (Beijing). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Tracking the Ti4+ substitution in phlogopite by spectroscopic imaging: A tool for unravelling the growth of micas at HP-HT conditions

Phlogopite solid-solutions have a wide pressure–temperature (P-T) stability field and are ubiquitous in a wide variety of geological settings, from deep lithosphere magmatic environments to upper crust metamorphic domains. Phlogopite composition represents therefore a valuable physical–chemical archive and may provide important information regarding its crystallization and the petrogenesis of the host-rock. In this paper we examine the phlogopite phenocrysts from the well-known Fort Regent mica-bearing lamprophyre minette from St. Helier (Island of Jersey, UK). Phlogopite phenocrystals from lamprophyres generally show normal-step and continuous compositional zoning, however those from the Fort Regent minette show a peculiar texture characterized by dark brown high-Ti (average TiO2 ca. 8.5 wt.%) cores enveloped by euhedral low- to mid-amplitude zonation due to oscillatory contents in Ti, Fe and Mg. Thermo-barometry modelling based on biotite-only composition yields relatively high P-T estimates (T ca. 970 ± 54 °C at P ca. 0.73 ± 0.13 GPa) for cores whereas lower values (T ca. 790 ± 54 °C at P ca. 0.29 ± 0.13 GPa) are obtained for the outer rims. Comparable temperatures (T ca. 1075 ± 54 °C) but extremely high and anomalous pressure values (P ca. 1.82 ± 0.13 GPa) are obtained for the yellowish inner rims. The combination of electron micro probe (EMP) analysis and single-crystal infra-red (FTIR) imaging in the OH-stretching region shows that the exceptional and oscillatory Ti contents are due to the Ti-vacancy substitution, typical of crystallization and growth processes of HP/HT environments. Raman imaging provides additional insight for this process, confirming the dominant dioctahedral nature for the Ti-Fe-rich cores and outer rims. Interpretation of thermobaric estimates obtained from the phlogopite composition-only model, based on the fine-scale compositional evolution, shows that pressure–temperature values from low-Ti high-Mg domains should be carefully evaluated because the substitution mechanisms during the dark mica growth are not univocally related to pressure–temperature variation of the crystallizing environment. Our results demonstrate how a multidisciplinary approach based on the combination of chemical investigations and vibrational spectroscopies could represent a valuable tool to evaluate pressure–temperature estimates from biotite composition-only thermo-barometry models and therefore to correctly unravel HP/HT petrogenetic processes at a very fine scale

TRY plant trait database - enhanced coverage and open access

10.1111/gcb.14904GLOBAL CHANGE BIOLOGY261119-18