Papers by Juan Luis Aguirre
Energies
The effects of biochar on different horticultural crops (lettuce, tomato, sweet pepper, and radis... more The effects of biochar on different horticultural crops (lettuce, tomato, sweet pepper, and radish) were evaluated in the Mediterranean climate. Biochar was produced by pyrolysis of Pinus pinaster wood chips at 550 °C and used at 1 (B1) and 2 (B2) kg/m2 application rates on six 3.5 m2 plots in each treatment, with two control plots (B0). No fertilizer was used. Treatment B1 led to a significant increase (p < 0.01) of 35.4%, 98.1%, 28.4%, and 35.2% in the mean fresh weight of radishes, lettuce, tomatoes, and sweet peppers, respectively. Treatment B2 resulted in an improvement of 70.7% in radishes, 126.1% in lettuce, 38.4% in tomatoes, and 95.0% in sweet peppers (p < 0.01). Significant differences between treatments B1 and B2 were observed in the radish, tomato, and sweet pepper crops but not in lettuce. The profitability of biochar application to these crops was studied by considering a biochar price of 800 EUR/t and applying a CO2 fixation subsidy, assuming the updated Februar...
Energies, 2022
In this work, chemical recycling as an alternative to conventional end-of-life treatments was stu... more In this work, chemical recycling as an alternative to conventional end-of-life treatments was studied. Two different types of end-of-life tires (ELT), truck tires and mix tires (50:50 mixture of passenger car and truck tires), were pyrolyzed in a batch microwave reactor. The influence of specific power (10, 20, and 30 W/g) on mass distribution was analyzed. The maximum liquid yield was attained at 10 W/g, while the maximum gas yield is obtained at 30 W/g. Liquid fractions were characterized by gas chromatography/quadrupole mass spectrometry (GC/qMS) to identify the main components, and major compounds were quantified. In all samples, limonene (3.76 ± 0.31–6.80 ± 2.37 wt. %) and BTEX (3.83 ± 0.20–1.19 ± 2.80 wt. %) were the main components. Major limonene concentration is obtained in oil produced from truck ELT while higher yields of aromatic compounds are obtained from mix ELT. The maximum BTEX concentration is obtained at 10 W/g being toluene the main compound with a concentration ...
Energies
This study assessed the effect of soil amendment with biochar on the production of some Mediterra... more This study assessed the effect of soil amendment with biochar on the production of some Mediterranean crops. Pine-derived biochar (B1) and partially pyrolyzed pine-derived biochar (B2) were used with a dose of 8 L/m2 in a corn crop, reporting a production increase of 38–270% over three years with B1, and no effect of B2 due to its poor quality. Olive stone-derived biochar (B3) was used in lavandin and vineyard crops with doses of 0.04–0.9 L/m2 and 0.37–2.55 L/m2, respectively. An increase of 23–25% in plant volume of lavandin was reported, while the production of grapes per plant was not significantly altered, although it increased by up to 66%. Soil analysis indicated that biochar does not significantly alter soil physicochemical parameters; therefore, biochar may affect plants by altering soil structure and increasing its cation exchange capacity and water management efficiency. Depending on its price, biochar application may be profitable for lavandin and corn crops, with a retur...
Molecules
The effects of two types of biochar on corn production in the Mediterranean climate during the gr... more The effects of two types of biochar on corn production in the Mediterranean climate during the growing season were analyzed. The two types of biochar were obtained from pyrolysis of Pinus pinaster. B1 was fully pyrolyzed with 55.90% organic carbon, and B2 was medium pyrolyzed with 23.50% organic carbon. B1 and B2 were supplemented in the soil of 20 plots (1 m2) at a dose of 4 kg/m2. C1 and C2 (10 plots each) served as control plots. The plots were automatically irrigated and fertilizer was not applied. The B1-supplemented plots exhibited a significant 84.58% increase in dry corn production per square meter and a 93.16% increase in corn wet weight (p << 0.001). Corn production was no different between B2-supplemented, C1, and C2 plots (p > 0.01). The weight of cobs from B1-supplemented plots was 62.3%, which was significantly higher than that of cobs from C1 and C2 plots (p < 0.01). The grain weight increased significantly by 23% in B1-supplemented plots (p < 0.01) and...
Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology
Energies
Lignocellulosic biomass pyrolysis could be an economically feasible option for forest management ... more Lignocellulosic biomass pyrolysis could be an economically feasible option for forest management as it reduces the need to burn litter and helps in fire prevention thus avoiding the release of carbon dioxide and other greenhouse gases into the atmosphere. This study characterises wood vinegar (WV) obtained via a continuous fast pyrolysis process in terms of its composition, ageing and herbicidal properties. The aqueous WV fraction had a moisture content of 84% in weight and contained more than 200 compounds. Acetic acid, hydroxyacetaldehyde and hydroxyacetone were the major components. No significant differences were found in WV composition according to the starting material (poplar, pine, pruning litter, forest waste). No residual aromatic polycyclic compounds that could be harmful to the environment were detected. In a series of climate-controlled glass chamber experiments, the WV proved to be as effective an inhibitor of seed germination and seedling growth as a contact herbicide...
Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology
Acta Botanica Mexicana, 2014
En este trabajo se abordan las relaciones entre el clima y la vegetación en el territorio de la v... more En este trabajo se abordan las relaciones entre el clima y la vegetación en el territorio de la vertiente del Pacífico Mexicano, considerada como una franja de 100 km de ancho que desde el litoral se extiende hacia tierra adentro y cuyos extremos norte y sur coinciden con la frontera de México con los Estados Unidos de América y con Guatemala respectivamente. Las relaciones fueron establecidas a partir del análisis bioclimático efectuado con los datos de precipitación y temperatura de 691 estaciones meteorológicas existentes en el área de estudio. La diagnosis bioclimática permitió identificar los macrobioclimas Mediterráneo y Tropical, los bioclimas Mediterráneo Pluviestacional Oceánico, Mediterráneo Xérico Oceánico, Mediterráneo Desértico Oceánico, Mediterráneo Hiperdesértico Oceánico, Tropical Pluvial, Tropical Pluviestacional, Tropical Xérico, Tropical Desértico y Tropical Hiperdesértico, y 30 isobioclimas. Los muestreos de campo se dirigieron hacia la caracterización fisionómic...
Open Journal of Ecology, 2016
This paper describes and analyzes floristic, structural and conservation features of the shrublan... more This paper describes and analyzes floristic, structural and conservation features of the shrubland occupied by Chersophilus duponti in the northwest corner of its world distribution range. This study relates the coverage, floristic composition with estimated lark density in the area. We identified four types of shrublands, three of them varied significantly in floristic composition for the habitats of this species in contrast with those of their world distribution: Cistus ladanifer scrubs; heaths dominated by Ericaceae, and scrubs dominated by the genera Lavandula, Thymus and Cytisus. The fourth type, dominated by aromatic chamaephytes and grass, fits descriptions of the bird's typical habitat. The areas sampled are subject to different categories of threats, the most significant being the natural succession process due to the cessation of grazing, reforestation measures and the use of flat areas for farmlands or other uses. The density of larks in this area was directly related to coverage-composition of plant community.
Southwest Naturalist, 2005
ABSTRACT. -A study of the growth of beech seedlings (F. sylvatica) in Central Spain , with medite... more ABSTRACT. -A study of the growth of beech seedlings (F. sylvatica) in Central Spain , with mediterranean climate, is presented. Two phases can be recognized; establishment and diferentiation, with diferent diameter and longitudinal growths . Summer rainfall affects both growth, with major weight than spring rainfall . A sumary table is presented with diameter, longitudinal growth and rainfall relations during seedling developement. Key words; Fagus sylvatica; seedlings; .growth; rainfalls; establishment; mediterranean climate .
Producción, depredación de hayucos y polini-zación cruzada en un hayedo mediterráneo (F sylvatica... more Producción, depredación de hayucos y polini-zación cruzada en un hayedo mediterráneo (F sylvaticaJ en dos Seed production and predated, parasited and empty seed percent age were studied in mast and non mast year. We examined search efficiency and fruit selection by Cydia fagiglandana. Parasited percentage over sound seeds was 18.54 and 52.07 for mast and non-mast. Empty seeds are related to total production and percentage of viable seeds was 66.75 and 26.8 for mast and non-m ast year. Results show that masting. strategy have accurancy even differences between mast and non-mast year are not very high. Fruit selection by Cydia just acts in the earliest phase when higher weight fruits are lacking of moth. Results suggest that the moth have a low searching range.
In this study we give data about sorne regenerative and competitive e processes in Mediterranean ... more In this study we give data about sorne regenerative and competitive e processes in Mediterranean beech fores t (Fagus sylvatica L.). We investigate mortality of seedlings of the current year, diameters distribution , and age of the seedlings. The data indicate that the first limitant factor of the beech regeneration is the drought summer of the first year. Another evidences show good regeneration of the beech under Pinus sylvestris L. canopy.
American Journal of Plant Sciences, 2012
This study was designed to examine relationships between climate and vegetation of the Pacific ri... more This study was designed to examine relationships between climate and vegetation of the Pacific rim of North America, from the Mediterranean deserts of California to Alaska's boreal taiga. Relations were inferred from temperature and rainfall data recorded at 457 weather stations and by sampling the vegetation around these stations. Climate data were used to construct climatograms, calculate forty one variables and detect main latitudinal and longitudinal gradients. In order to identify the best functions able to relate our variables, polynomial and non-polynomial regressions were performed. The k-means algorithm was the clustering method used to validate the variables that could best support our bioclimatic classification. The variable that best fitted our classification was finally used to prepare a discriminatory key for bioclimates. Across this extensive area three macrobioclimates were identified, Mediterranean, Temperate and Boreal, within which we were able to distinguish nine bioclimates. Finally, we relate the different types of potential natural vegetation to each of these bioclimates and describe their floristic composition and physiognomy.
In this study we address the relationship between climate and vegetation in the territory of the ... more In this study we address the relationship between climate and vegetation in the territory of the Mexican Pacific rim, a strip of 100 km wide that extends from the coast landwards with its north and south limits coinciding with Mexico's border with the United States of America and Guatemala, respectively. Relationships were established from bioclimatic analysis performed with temperature and precipitation data from 691 weather stations existing in the study area. The bioclimatic diagnosis identified the Mediterranean and Tropical macrobioclimates,
A comparative study of the North American salt marshes between Magdalena Plain (Baja California, ... more A comparative study of the North American salt marshes between Magdalena Plain (Baja California, 24 ° N) and the north of San Francisco (California 38 ° N) is made in order to establish relationships between fioristic and zonal gradients. The sigmatistic-phytosociological method along with Average Linkage Clustering are used to describe the zonation of these salt marshes and to define the optimum zone of several halophilous plants and communities.
Uploads
Papers by Juan Luis Aguirre