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Purpose. To determine and evaluate some ceramic properties (plasticity index, linear shrinkage, porosity, and bulk density) of clay deposits from Anambra Basin of South Eastern Nigeria. Methods. Fifteen clay samples were collected by trenching methods. Samples were tested for plasticity index, linear shrinkage, loss on ignition, porosity, and bulk density using test standards developed by the American Society of Test and Materials. Result data were evaluated using tabulation and statistical graphs. Findings. Mean plasticity index of the samples range from 14.3 to 21.3. Mean linear shrinkage is from 2.5 to 5.5%. Mean loss on ignition is from 6.56 to 9.75%. Mean porosities is from 6.9 to 30.1%. Mean bulk density is between 2362 and 1692 kg/m3. The ceramic properties of the deposits varied across location, and no single deposit has the complete set of ceramic properties needed in ceramic industries. Originality. To the best of the authors' knowledge, this is the first research that looked into the distributions of ceramic properties of clay deposits in Anambra geologic Basin. Practical implications. The findings will help investors to make informed decisions on clay deposits in their investment plans and can be used as supporting document when applying for mining titles. [ABSTRACT FROM AUTHOR]

Some species intrinsically have a high invasiveness capacity, shown by high phenotypic plasticity and rapid growth, enabling a wide distribution across their native habitats and successful invasion in the introduced range. For such species, information from native habitats is critically important. An example is Glechoma hederacea, native to Eurasia but introduced and widespread in the USA. Our main objective was to investigate variation in traits of native G. hederacea populations across contrasting habitats: open, forest edge and understory. Vegetation was sampled and the ecophysiological and morphological traits were measured with accompanying environmental parameters. Results showed that in native habitats environmental conditions cover wide gradients of light and soil moisture. Plants had the highest cover in nutrient-rich, shaded habitats, representing the optimal habitat, indicating shade tolerance of G. hederacea. Plants from forest understory exhibited strong similarities in investigated traits to plants from the forest edge, even though this was a drier, sunnier habitat. Plants from open, sunny habitats experienced stress as indicated by the quantum efficiency of PSII and significantly higher sexual reproduction. Results show that G. hederacea is moderately tolerant simultaneously to shade and drought, a characteristic that has been reported for numerous invasive species, while at the same time it shares some characteristics with weedy plants. [ABSTRACT FROM AUTHOR]

Platanus acerifolia (Aiton) Willd was generated spontaneously around the beginning of the 1600s in Spain between Platanus orientalis L. and Platanus occidentalis L. The study was carried out on P. acerifolia trees in different sites in Rome in the period April-July 2019. Trees comparable for size were selected in A sites (historical parks), B sites (high traffic density streets) and in C sites (high traffic density avenues along the Tevere River characterized by a large water availability). At the morphological level, leaf area (LA) was significantly higher in A and C sites and leaf tissue density (LTD) in C sites. At anatomical level, the total leaf thickness (LT). the palisade parenchyma thickness (Pt), the spongy parenchyma thickness (St) and the abaxial epidermis thickness (Abet) were significantly higher in A sites, while the adaxial cuticle thickness (Adct) and the adaxial epidermis thickness (Adet) in B sites. The ratio between palisade and spongy parenchyma thickness (P/S) was significantly higher in C sites. The plasticity index (PI, 0.42) was calculated on all the considered leaf traits. Among the morphological traits, LTD had the highest plasticity (0.49) and among the anatomical traits, trichomes density (TD) and Adet (0.74 and 0.54, respectively). Overall, the results highlight the large adaptability of P. acerifolia to grow in different sites in Rome through several changes in leaf morphological and anatomical traits. [ABSTRACT FROM AUTHOR]

Morphological and ecophysiological traits showed by male and female Populus tomentosa Carr. trees were studied under various degrees of water and alkaline stresses. The results showed that different adaptations to drought and alkaline stresses were adopted by each gender; males possessed a much higher tolerance to both stresses compared to females. In contrast to females, the males exhibited a lower inhibition in total biomass, total leaf area, net photosynthetic rate, stomatal conductance, leaf carbon and nitrogen concentrations as well as water- and nitrogen-use efficiency in response to drought and alkaline stresses. Nevertheless, compared to the males, the females showed a higher plasticity in root biomass/shoot biomass ratio, fine root/coarse root ratio, and intrinsic water-use efficiency, indicating that the males and females differed in some of trade-offs between growth and stress defence to maximize water and nitrogen gains under both stress conditions. [ABSTRACT FROM AUTHOR]

Copyright of Academic Journal of Agriculture / Akademik Ziraat Dergisi is the property of University of Ordu, Faculty of Agriculture, Academic Journal of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: We studied the phenotypic plasticity of physiological and growth traits in two distinct clones of common reed (Phragmites australis (Cav.) Trin. Ex Steud.). Replicates of a clone from Denmark (DK clone) belonging to the European temperate P. australis and a clone from Algeria (ALG clone) belonging to the African-Mediterranean gene pool of P. australis were grown in phytotrons in a factorial block design at 15°C or 25°C daytime temperature and high or low fertilization level. Plant growth, tissue nutrient concentrations, photosynthetic pigments and photosynthetic characteristics were measured. Phenotypic plasticity was quantified for the measured traits as plasticity indices in relation to temperature and fertilization. The plasticity index was calculated as the difference between the maximum and the minimum mean value divided by the maximum mean value of a parameter within a treatment. The functional significance of the plasticity and its contribution to plant fitness was assessed by correlation of the plant traits to plant biomass as a proxy for fitness. The DK clone responded much more to temperature than the ALG clone, which responded more to fertilization, and both clones responded to high fertilization with lower allocation of biomass to roots and rhizomes. The ALG clone had a higher nutrient demand due to its large and fast biomass development. Hence, for most traits, the calculated plasticity indices for fertilization were highest for the ALG clone, especially within photosynthetic parameters and pigments, and the plasticity indices for temperature were highest for the DK clone, especially within growth parameters. In both clones, photosynthetic pigments, biomass allocation to leaf blades and rhizomes, the shoot:root ratio as well as leaf and shoot production rates were highly correlated to fitness. These traits also had a relatively high degree of plasticity, indicating a functional significance of plasticity, but several traits that showed high plasticity did not correlate with fitness (e.g. P max). We conclude that the responses of the two contrasting P. australis genotypes to temperature and fertilization are genetically determined and related to the climatic conditions at the site of their origin. Although phenotypic plasticity per se is not a precondition for plant fitness, the genetically determined differences in the degree of phenotypic plasticity of distinct P. australis genotypes to temperature and nutrient availability affect fitness and may influence how the genotypes will respond to global environmental change. [Copyright &y& Elsevier]

Abstract: The low nutrient availability of the acidic and sandy soils of Galicia (Northwest Spain) is probably the main environmental factor limiting forest primary productivity in the area. These particular edaphic conditions could have imposed selective pressures on maritime pine populations leading to specific local adaptations. We first assessed the nutritional status of 22 young contemporary Pinus pinaster plantations in Northwest Spain, and then analysed the response to fertilization in three family×fertilization trials, and how this response varied across sites and genotypes. Growth of P. pinaster in Northwest Spain appeared to be largely limited by nutrient availability, where most of the plantations showed severe nutrient deficiencies, especially in P and Mg. According to these deficiencies, a strong positive response to nutrient additions was observed in the three trials, with height increments of up to 30% compared with the unfertilized control. However, the response to fertilizers was very variable from site to site, and in some cases did not agree with the foliar nutritional diagnosis. The response to fertilization was also significantly affected by pine genotype, suggesting that the plastic response to nutrient additions within each environment was under genetic control. However, the family response to nutrient availability was not consistent across sites, and no significant differences among families were observed for the RDPI plasticity index – a single index that summarizes the phenotypic change in multiple environments – when analysed across environments. The strong environmental component modulating phenotypic responses to fertilization could impose an important obstacle to evolve specific adaptations to the local edaphic conditions, as well as to artificially select genotypes adapted to different environments and silviculture regimes. [Copyright &y& Elsevier]

Abstract: The main objective of this study was to look into the phenotypic plasticity of the semi-deciduous Mediterranean shrub, Halimium halimifolium. We studied morphological, allocation and physiological traits to determine which characters were more plastic and contribute in a greater extent to the acclimation ability of the species. We present a phenotypic plasticity index for morphological, physiological and allocation traits, which we have applied in the most contrasted plant communities where the species grows naturally. Data published by Díaz Barradas, M.C., García Novo, F. [1987. The vertical structure of Mediterranean scrub in Doñana National Park (SW Spain). Folia Geobotanica Phytotaxonomica 22, 415–433; 1988. Modificación y extinción de la luz a través de la copa en cuatro especies de matorral en el Parque Nacional de Doñana. Monografias Instituto Pirenaico de Ecologia 4, 503–516; 1990. Seasonal changes in canopy structure in two mediterranean dune shrubs. Journal of Vegetation Science 1, 31–40.], Díaz Barradas, M.C., Zunzunegui, M., García Novo, F. [1999a. Autoecological traits of Halimium halimifolium in contrasted habitats under Mediterranean type climate. Folia Geobotanica 34, 189–208.] and Zunzunegui et al. [Zunzunegui, M., Díaz Barradas, M.C., García Novo, F. 1997. Autoecological notes of Halimium halimifolium. Lagascalia 19, 725–736. Sevilla, Spain; Zunzunegui, M., Díaz Barradas, M.C., Fernández Baco, L., García Novo, F. 1999. Seasonal changes in photochemical efficiency in leaves of Halimium halimifolium a Mediterranean semideciduous shrub. Photosynthetica 36, 17–31; Zunzunegui, M., Díaz Barradas, M.C., García Novo, F. 2000. Different phenotypic response of Halimium halimifolium in relation to groundwater availability. Plant Ecology 148, 165–174; Zunzunegui, M., Díaz Barradas, M.C., Aguilar, F., Ain-Lhout, F., Clavijo, A., García Novo, F. 2002. Growth response of Halimium halimifolium at four sites with different soil water availability regimes in two contrasted hydrological cycles. Plant and Soil 247, 271–28.] have been re-appraised and combined with original data. Phenotypic plasticity index showed that the highest plasticity of the species was physiological, and especially for the traits related with water control. This high physiological plasticity appears mainly between seasons (September–November) rather than between sites. Plasticity in allocation traits showed intermediate values between physiological and morphological traits. [Copyright &y& Elsevier]