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1.
Int J Phytoremediation ; 24(10): 1014-1024, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34694940

RESUMEN

Treated wastewater can partly meet the requirements of water for irrigating tree crops in dry areas to better utilize, produce biomass and reduce land degradation. Seedlings of Acacia nilotica, Azadirachta indica, Eucalyptus camaldulensis, Prosopis cineraria, P. juliflora, Tamarix aphylla, Salvadora persica, S. oleoides and Tecomella undulata were planted and irrigated with bore-well (BW) and treated wastewater (WW) at ½ET (Evaporation-transpiration) and ¾ET. Plants irrigated at BW1/2 attained less height and collar diameter, and showed low growth increments and dry biomass. These variables increased by 1.2-2.0-fold at WW3/4 irrigation. Plants produced 1.4-fold higher biomass with WW over BW, whereas it was 1.5-fold higher at ¾ET over ½ET. Responses of species to BW/WW irrigation differed in biomass allocation to roots and other parts as a mechanism to uptake water and nutrients. Conclusively, A. nilotica, A. indica, P. juliflora and T. aphylla had stronger preference to increased irrigation level, whereas E. camaldulensis, S. persica, S. oleoides and T. undulata had preferred nutrients added through treated wastewater. A. nilotica, E. camaldulensis, P. juliflora and A. indica were best species in growth and biomass production and wastewater utilization. These can be replicated in urban afforestation to enhance bio-product and reduce degradation in environmental quality.


Wastewater (WW) is an alternative source of water in dryland afforestation. Wastewater was characterized and utilized in growing tree plantation in Indian arid zone. Plant growth and biomass increased with treated wastewater irrigation. Responses of different species to wastewater differed depending on their phytoremediation ability by nutrient uptake and biomass distribution. Tree species differed in their preferences to increased quantity of irrigation water and nutrients added through wastewater application.


Asunto(s)
Árboles , Aguas Residuales , Biodegradación Ambiental , Biomasa , Agua
2.
Mar Environ Res ; 162: 105195, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33129167

RESUMEN

The Alborán Sea sardine (Sardina pilchardus) is the most abundant small pelagic fish in the Mediterranean Sea. Along the northern coast of the Alborán Sea, Málaga and Almería Bay are two important nursery grounds with contrasting oceanographic characteristics. Post-larval stages of S. pilchardus were collected during the late autumn and late winter along with the mesozooplankton community. We examined the influence of feeding behavior on larval growth using environmental variables, daily growth metrics, otolith biometry, stable isotope analysis and trophodynamics. Trophic positions were calculated using mesoozooplankton as potential prey for S. pilchardus. During both seasons, we observed faster growth in larger otoliths that also corresponded to higher trophic positions. Our results indicate that the isotopic signature of larvae is highly influenced by the mesozooplankton community structure. Moreover, the trophic variables showed a significant linear relationship with the estimated ages for all larvae indicating dietary changes throughout ontogenic development.


Asunto(s)
Bahías , Peces , Animales , Ecosistema , Mar Mediterráneo , Alimentos Marinos
3.
Biol Rev Camb Philos Soc ; 94(3): 1161-1178, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30681759

RESUMEN

The concept of growth rings is little discussed in the literature and their treatment remains somewhat confusing in terms of the diversity of structures described. This situation has a major impact on the study of growth rings in tropical species, in which variations and complexity are greater and accuracy of identification less good. The rigid conceptual delimitations used by dendrochronologists and wood anatomists of temperate regions cannot be applied to the study of growth rings in most tropical species, which has led to neglect of this subject. With the objective of discussing the concept of growth rings, the present study consists of a survey of anatomical, periodicity, causal and evolutionary aspects of the treatment of these structures as evidenced in previous studies, and the evaluation of their application and limitations to the development of this concept. Anatomical aspects arise through radial integrity, or the presence of early and late wood; the degree of distinction of the rings, which may vary from well to poorly defined; and tangential continuity, meaning that rings may form a complete circle in the transverse section of the trunk, or instead be tangentially discontinuous, lens-shaped or in wedges. In addition there are a diversity of anatomical markers which enable us to recognize growth rings. Regarding periodicity, the rings may be annual, infra-annual or supra-annual. Causal aspects include genetic, endogenous and environmental components. Evolutionary aspects continue to be insufficiently investigated, and although most comparative studies treat growth rings recognized by different markers as though they were a single character, it remains questionable whether they can be regarded as homologous or the result of homoplasy. We conclude that the elaboration of a robust but broad definition which can include all the variation observed in growth rings of tropical species is a complex task, which is only possible by overcoming the restrictions adopted by dendrochronologists and wood anatomists of temperate regions for whom growth rings are essentially annual, strongly demarcated, tangentially continuous and restricted to the most pronounced markers.


Asunto(s)
Desarrollo de la Planta/fisiología , Plantas/clasificación , Clima Tropical , Ecosistema , Especificidad de la Especie , Madera/anatomía & histología , Madera/fisiología
4.
Neotrop. ichthyol ; 16(4): e180051, out. 2018. tab, graf, ilus, mapas
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-976299

RESUMEN

Using morphometric measurements and wavelets functions, the asterisci otoliths of curimatã, Prochilodus nigricans were analysed to identify the variation in shape and growth increment of individuals from Solimões, Japurá and Negro rivers of the Amazon basin, Brazil. The morphometric and morphological analyses did not reveal evidences of population segregation among rivers, but variations were found in the estimation of otolith growth increment. Also, the otolith shape showed a high variability between individuals, identifying four morphotypes. Morphotype 1 shows a more oval shape with a posterior zone clearly rounded; Morphotype 2 shows the posterior zone rounded, but the anterior end is more elongated; Morphotype 3 shows a completely different shape, elliptic-pentagonal and Morphotype 4 shows the posterior zone rounded, but the anterior end is more elongated and it is the pattern with antirostrum and rostrum more pointed and a deep notch. Therefore, the otolith shape exhibited a phenotypic plasticity that it was not associated with the metabolism of otolith growth. Whereas the otolith shape indicated a homogeneity in the sound perception through Amazon basin, the growth rates revealed an adaptive mechanism to environmental conditions or migratory process of this species.(AU)


Medidas e funções wavelets dos otólitos asteriscus de curimatã, Prochilodus nigricans foram analisados para identificar a variação da forma e do incremento de crescimento dos indivíduos dos rios Solimões, Japurá e Negro da bacia Amazônica, Brasil. As análises morfométricas e morfológicas não revelaram evidências de segregação populacional entre os rios, mas foram encontradas variações na estimativa do incremento do crescimento dos otólitos. Além disso, a forma do otólito mostrou uma alta variabilidade entre os indivíduos, identificando quatro morfotipos. O Morfotipo 1 mostra uma forma mais oval, com zona posterior levemente arredondada; Morfotipo 2 mostra a zona posterior arredondada, mas a extremidade anterior é mais alongada; Morfotipo 3 mostra uma forma completamente diferente, elíptico-pentagonal e Morfotipo 4 mostra a zona posterior arredondada, mas a extremidade anterior mais alongada e ele tem padrão com antirostrum e rostrum mais pontiagudos e abertura profunda. Portanto, a forma do otólito exibiu uma plasticidade fenotípica que não foi associada ao metabolismo do crescimento do otólito. No entanto a forma do otólito indicou uma homogeneidade através da percepção do som na bacia Amazônica, e as taxas de crescimento revelaram um mecanismo adaptativo às condições ambientais ou ao processo migratório da espécie.(AU)


Asunto(s)
Animales , Membrana Otolítica/crecimiento & desarrollo , Migración Animal/fisiología , Characiformes/crecimiento & desarrollo , Peces/crecimiento & desarrollo
5.
J Fish Biol ; 86(3): 907-23, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25545134

RESUMEN

The main goal of this study was to examine otolith microstructure and to estimate the age and growth of European hake Merluccius merluccius from the eastern Mediterranean Sea. One hundred and twenty-nine specimens ranging from 102 to 438 mm in total length (LT ) were used. Age estimations were based on the study of the otolith microstructure, which was revealed after grinding both frontal sides of otoliths. The enumerations of the daily growth increments (DGI) as well as their width (WDGI ) measurements were made on calibrated digital images. The number of DGI in otoliths ranged between 163 and 717. Four phases in the WDGI evolution were distinguished: (1) larval-juvenile pelagic phase, with an increasing trend in WDGI up to the 60th DGI, (2) settlement phase, with a short-term deceleration in WDGI between the 61st and 150th DGI, (3) juvenile demersal phase, characterized by a stabilization of WDGI from 151st to 400th DGI and (4) adult phase, with a decreasing trend in WDGI after the 400th DGI. Age, sex and month of formation were found to affect the WDGI in all phases, with the exception of age at the juvenile demersal phase. The power curve with intercept model described best the relationship of M. merluccius LT with age (TDGI ), according to Akaike criteria, revealing differences in growth between females [LT = 65 · 36(TDGI )(0 · 40) - 388 · 55] and males [LT = 69 · 32(TDGI )(0 · 37) - 352 · 88] for the sizes examined. The mean daily growth rates were 0·61 mm day(-1) for females and 0·52 mm day(-1) for males, resulting in an LT of 283 and 265 mm at the end of their first year of life. In comparison with previous studies on the Mediterranean Sea, the results of this study showed a greater growth rate, similar to results from tagging experiments and otolith microstructure analyses for M. merluccius in other geographic areas.


Asunto(s)
Gadiformes/crecimiento & desarrollo , Membrana Otolítica/anatomía & histología , Animales , Femenino , Masculino , Mar Mediterráneo , Modelos Estadísticos , Análisis de Regresión
6.
Ecol Evol ; 4(10): 1972-80, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24963390

RESUMEN

This research is the first published study to report a relationship between climate variables and plastron growth increments of turtles, in this case the endangered Nova Scotia Blanding's turtle (Emydoidea blandingii). We used techniques and software common to the discipline of dendrochronology to successfully cross-date our growth increment data series, to detrend and average our series of 80 immature Blanding's turtles into one common chronology, and to seek correlations between the chronology and environmental temperature and precipitation variables. Our cross-dated chronology had a series intercorrelation of 0.441 (above 99% confidence interval), an average mean sensitivity of 0.293, and an average unfiltered autocorrelation of 0.377. Our master chronology represented increments from 1975 to 2007 (33 years), with index values ranging from a low of 0.688 in 2006 to a high of 1.303 in 1977. Univariate climate response function analysis on mean monthly air temperature and precipitation values revealed a positive correlation with the previous year's May temperature and current year's August temperature; a negative correlation with the previous year's October temperature; and no significant correlation with precipitation. These techniques for determining growth increment response to environmental variables should be applicable to other turtle species and merit further exploration.

7.
Proc Natl Acad Sci U S A ; 110(29): 11736-41, 2013 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-23818577

RESUMEN

Above-ground thermonuclear weapons testing from 1952 through 1962 nearly doubled the concentration of radiocarbon ((14)C) in the atmosphere. As a result, organic material formed during or after this period may be radiocarbon-dated using the abrupt rise and steady fall of the atmospheric (14)C concentration known as the bomb-curve. We test the accuracy of accelerator mass spectrometry radiocarbon dating of 29 herbivore and plant tissues collected on known dates between 1905 and 2008 in East Africa. Herbivore samples include teeth, tusks, soft tissue, hair, and horn. Tissues formed after 1955 are dated to within 0.3-1.3 y of formation, depending on the tissue type, whereas tissues older than ca. 1955 have high age uncertainties (>17 y) due to the Suess effect. (14)C dating of tissues has applications to stable isotope (paleo)ecology and wildlife forensics. We use data from 41 additional samples to determine growth rates of tusks, molars, and hair, which improve interpretations of serial stable isotope data for (paleo)ecological studies. (14)C dating can also be used to calculate the time interval represented in periodic histological structures in dental tissues (i.e., perikymata), which in turn may be used as chronometers in fossil teeth. Bomb-curve (14)C dating of confiscated animal tissues (e.g., ivory statues) can be used to determine whether trade of the item is legal, because many Convention of International Trade of Endangered Species restrictions are based on the age of the tissue, and thus can serve as a powerful forensic tool to combat illegal trade in animal parts.


Asunto(s)
Animales Salvajes/metabolismo , Radioisótopos de Carbono/análisis , Ciencias Forenses/métodos , Armas Nucleares , Plantas/química , Datación Radiométrica/métodos , África Oriental , Animales , Conservación de los Recursos Naturales/métodos , Ecología/métodos , Cabello/química , Espectrometría de Masas/métodos , Diente/química
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