Juan Arroyo | Universidad de Sevilla (original) (raw)
Papers by Juan Arroyo
La necesidad de la experimentación en ecología y conservación: una aproximación para la restaurac... more La necesidad de la experimentación en ecología y conservación: una aproximación para la restauración forestal en el Campo de Gibraltar. VI Jornadas de Flora, Fauna y Ecología del Campo de Gibraltar. Algeciras, Octubre 2003.<br><br>
Reivindicacion de la figura de Darwin como botanico, muchas veces ignorada por el publico en gene... more Reivindicacion de la figura de Darwin como botanico, muchas veces ignorada por el publico en general, ademas el autor llama la atencion sobre la gran deuda que tienen todos los botanicos con el.
Pollen transfer, and hence sharing of pollinators, among Primula veris, Narcissus assoanus, and P... more Pollen transfer, and hence sharing of pollinators, among Primula veris, Narcissus assoanus, and Potentilla tabernaemontani in Northern Spain is demonstrated in the study of pollen loads on their stigmas. The length of style in both P. veris and N. assoanus is dimorphic (the former being a typical distylous species); they resemble each other in flower morphology (narrow-tubed), color, and nectar characteristics. Therefore, interspecific pollen transfer between these two species shows a pattern related to these similarities. It is inferred that the pattern of interspecific pollen transfer is mediated mainly by long-tongued pollinators seeking nectar, and that of intraspecific pollen transfer by long- and short-tongued pollinators feeding on nectar and pollen, respectively. The floral features of P. tabernaemontani are markedly different, especially in flower architecture (open) and reward (pollen). Accordingly, pollen transfer to other species is reduced, the long-styled flowers of N....
Santos-Gally, R., Perez-Barrales, R., Arroyo, J., Jordano, P., Valido, A., Pico, X., Narbona, E. ... more Santos-Gally, R., Perez-Barrales, R., Arroyo, J., Jordano, P., Valido, A., Pico, X., Narbona, E. (2013). X Reunion anual de Ecoflor. Ecosistemas 22(2):125. Doi.: 10.7818/ECOS.2013.22-2.20
Acta Botanica Malacitana, 2007
RÉSUMÉ. Structure et diversité de la strate arbustive des forêts de la Péninsule Tingitane (Maroc... more RÉSUMÉ. Structure et diversité de la strate arbustive des forêts de la Péninsule Tingitane (Maroc). Cette étude concerne les communautés végétales arbustives des massifs forestiers sur substrat gréseux couvrant la Péninsule Tingitane au nord ouest du Maroc. La structure et la diversité de ces communautés ont été étudiées sur la base de 98 relevés représentatifs. Les subéraies (Quercus suber) sont les formations forestières naturelles les plus représentatives et les plus diversifiées de l´aire d´étude. L´altitude s’est révélée être un facteur écologique très discriminant, en séparant clairement les communautés arbustives des forêts des hautes montagnes. Au niveau des zones de basses altitudes, la fertilité, l´acidité et la perturbation anthropique jouent un rôle déterminant dans la distribution des communautés végétales arbustives. Cette distribution semble exprimer la dynamique de la végétation selon un gradient de conservation-perturbation. En conclusion, l´étude souligne l´intérêt...
Plant biology (Stuttgart, Germany), Jan 4, 2017
Narcissus papyraceus is a style dimorphic species with two floral forms, with anthers at similar ... more Narcissus papyraceus is a style dimorphic species with two floral forms, with anthers at similar height and stigmas above (long-styled L) and below (short-styled S) the anther level. The species is self-incompatible, but intra and inter-morph compatible. Populations are either dimorphic (including both morphs) in the region of the Strait of Gibraltar, or L-monomorphic (with only L plants) in the inland of the Iberian Peninsula. This variation correlates with the most common floral visitors, be these primarily long-tongued and short-tongued pollinators respectively, a rare condition in Mediterranean plants. The maintenance of S-flowers relies on long-tongued insects, as only those deliver pollen to short-styled stigmas. Narcissus flowers present a long and narrow tube, at the bottom of which nectar accumulates, and a floral corona, which has been proposed as an important trait for the attraction of pollinators. Here we tested the importance of the corona on the pollination of L and S...
Plant biology (Stuttgart, Germany), Jan 4, 2017
Plant populations invading new environments might compromise their fitness contribution to the ne... more Plant populations invading new environments might compromise their fitness contribution to the next generation, owing to the lack of native specialist pollinators and/or potential mates. Thus, changes in plant mating system and traits linked to it are expected in populations colonising new environments where selection would favour selfing and floral traits that maximise reproductive output. To test this, we studied native (Mexico) and non-native (Spain) populations of the obligate sex reproducing annual weed Datura stramonium. Flower size, herkogamy, total number of seeds per plant, number of visits by and type of pollinators, and inbreeding depression, were assessed in native and non-native populations. Finally, we measured phenotypic selection on corolla size and herkogamy in each population. Flower size and herkogamy showed wide and similar variation in both ranges. However, the largest average flower size was found in one non-native population whereas the highest average positiv...
Flora, 1990
Results: The project comes with an innovative design that was achieved through the aforementioned... more Results: The project comes with an innovative design that was achieved through the aforementioned methodology using the Araucoply material and solving the initial problem for which the project is made. Conclusions: Two arc options are made where the significant change is in the design of the joints that takes a tensegrity to another, this change is made in order to save material and facilitate the processing of the parts.
Quercus, 2004
Biblioteca de la Universidad Complutense de Madrid, Base de datos de artículos de revistas, ...
Forest Systems, Aug 1, 2003
El paisaje forestal mediterráneo que vemos en la actualidad es el resultado de la actuación del h... more El paisaje forestal mediterráneo que vemos en la actualidad es el resultado de la actuación del hombre y su gestión de los recursos a lo largo de la Historia (Le Houérou, 1981; McNeill, 1992; Marañón y Ojeda, 1998). Entre los procesos que han contribuido a la deforestación de la Cuenca Mediterránea, Thirgood (1981) ha destacado los siguientes: la transformación del bosque en cultivos y pastos, la explotación de ma-dera para la construcción de barcos, la extracción de combustible para uso doméstico o para la minería, las guerras e invasiones, los incendios y el sobrepastoreo. Los bosques del Rif, y en particular de la Península Tingitana (norte de Marruecos), han sufrido episodios intensos de perturbación que han sido más acentuados en la época reciente (Mikesell, 1960; Reille, 1977; Taiqui, 1997). La mayor parte de los bosques actuales de Marruecos son testigos de una explotación intensa, que se refleja en su estructura y composición. Excepcionalmente, los morabitos o «bosques sagrados» han sido respetados en señal de respeto hacia el santo musul
Proceedings. Biological sciences / The Royal Society, Aug 22, 2015
Many of the macroevolutionary processes that have shaped present-day phylogenetic patterns were c... more Many of the macroevolutionary processes that have shaped present-day phylogenetic patterns were caused by geological events such as plate tectonics and temporary land-bridges. The study of spatial patterns of phylogenetic diversity can provide insights into these past events. Here we focus on a western Mediterranean biodiversity hotspot located in the southern Iberian Peninsula and northwest Africa, two regions that are separated by the Strait of Gibraltar. We explore the spatial structure of the phylogenetic relationships within and across large-scale plant assemblages. Significant turnover in terminal lineages tends to occur between landmasses, whereas turnover in deep lineages tends to occur within landmasses. Plant assemblages in the western ecoregions of this hotspot tend to be phylogenetically overdispersed but are phylogenetically clustered on its eastern margins. We discuss our results in the light of potential scenarios of niche evolution (or conservatism) and lineage diver...
98 relevés représentatifs des massifs forestiers du nord du Maroc ont été réalisés. Les subéraies... more 98 relevés représentatifs des massifs forestiers du nord du Maroc ont été réalisés. Les subéraies sont les formations forestières les plus représentatives et les plus diversifiées dans l'aire d'étude. En effet, elles représentent une richesse spécifique et une richesse en taxons endémiques remarquables. Chez les formations forestières dominées par Quercus suber et Q. canariensis, l'altitude, la fertilité du sol et la perturbation anthropique jouent un rôle primordial dans la distribution des espèces. Cette distribution semble exprimer la dynamique de la végétation selon un gradient de conservation-perturbation. D'autres parts, la structure démographique des subéraies étudiées a montré un déficit évident de régénération naturelles.
Botanical Journal of the Linnean Society, 2015
Heterostyly and related polymorphisms (e.g. stigma-height dimorphism) have been used as model sys... more Heterostyly and related polymorphisms (e.g. stigma-height dimorphism) have been used as model systems for studying the origin and maintenance of plant population variability. Stigma-height dimorphism frequently occurs in Narcissus and is associated with a particular flower shape. In the present study, we describe a new, peculiar case of stigma-height dimorphism in Narcissus broussonetii, a species on the margin of the geographical distribution of the genus. We determined the stylar condition of N. broussonetii and its variation across populations, analyzed perianth morphology and its relationship with stylar variation, and compared this species with other stylar dimorphic species of the genus. We also studied the incompatibility system and pollination ecology of the species. Narcissus broussonetii is a style-dimorphic species, as suggested in early studies that were subsequently neglected, and displays unusual flower morphology, with a long floral tube and a virtual absence of a corona. The species shows a late-(ovarian) acting incompatibility system and crosses within and between morphs are fertile. We observed short-tongued diurnal and long-tongued nocturnal pollinators. Our findings confirm that the presence of the observed dimorphism across populations is most probably the result of the joint action of a nonheteromorphic incompatibility system, extremely long and narrow floral tubes, and a combined role of short-and long-tongued pollinators.
La necesidad de la experimentación en ecología y conservación: una aproximación para la restaurac... more La necesidad de la experimentación en ecología y conservación: una aproximación para la restauración forestal en el Campo de Gibraltar. VI Jornadas de Flora, Fauna y Ecología del Campo de Gibraltar. Algeciras, Octubre 2003.<br><br>
Reivindicacion de la figura de Darwin como botanico, muchas veces ignorada por el publico en gene... more Reivindicacion de la figura de Darwin como botanico, muchas veces ignorada por el publico en general, ademas el autor llama la atencion sobre la gran deuda que tienen todos los botanicos con el.
Pollen transfer, and hence sharing of pollinators, among Primula veris, Narcissus assoanus, and P... more Pollen transfer, and hence sharing of pollinators, among Primula veris, Narcissus assoanus, and Potentilla tabernaemontani in Northern Spain is demonstrated in the study of pollen loads on their stigmas. The length of style in both P. veris and N. assoanus is dimorphic (the former being a typical distylous species); they resemble each other in flower morphology (narrow-tubed), color, and nectar characteristics. Therefore, interspecific pollen transfer between these two species shows a pattern related to these similarities. It is inferred that the pattern of interspecific pollen transfer is mediated mainly by long-tongued pollinators seeking nectar, and that of intraspecific pollen transfer by long- and short-tongued pollinators feeding on nectar and pollen, respectively. The floral features of P. tabernaemontani are markedly different, especially in flower architecture (open) and reward (pollen). Accordingly, pollen transfer to other species is reduced, the long-styled flowers of N....
Santos-Gally, R., Perez-Barrales, R., Arroyo, J., Jordano, P., Valido, A., Pico, X., Narbona, E. ... more Santos-Gally, R., Perez-Barrales, R., Arroyo, J., Jordano, P., Valido, A., Pico, X., Narbona, E. (2013). X Reunion anual de Ecoflor. Ecosistemas 22(2):125. Doi.: 10.7818/ECOS.2013.22-2.20
Acta Botanica Malacitana, 2007
RÉSUMÉ. Structure et diversité de la strate arbustive des forêts de la Péninsule Tingitane (Maroc... more RÉSUMÉ. Structure et diversité de la strate arbustive des forêts de la Péninsule Tingitane (Maroc). Cette étude concerne les communautés végétales arbustives des massifs forestiers sur substrat gréseux couvrant la Péninsule Tingitane au nord ouest du Maroc. La structure et la diversité de ces communautés ont été étudiées sur la base de 98 relevés représentatifs. Les subéraies (Quercus suber) sont les formations forestières naturelles les plus représentatives et les plus diversifiées de l´aire d´étude. L´altitude s’est révélée être un facteur écologique très discriminant, en séparant clairement les communautés arbustives des forêts des hautes montagnes. Au niveau des zones de basses altitudes, la fertilité, l´acidité et la perturbation anthropique jouent un rôle déterminant dans la distribution des communautés végétales arbustives. Cette distribution semble exprimer la dynamique de la végétation selon un gradient de conservation-perturbation. En conclusion, l´étude souligne l´intérêt...
Plant biology (Stuttgart, Germany), Jan 4, 2017
Narcissus papyraceus is a style dimorphic species with two floral forms, with anthers at similar ... more Narcissus papyraceus is a style dimorphic species with two floral forms, with anthers at similar height and stigmas above (long-styled L) and below (short-styled S) the anther level. The species is self-incompatible, but intra and inter-morph compatible. Populations are either dimorphic (including both morphs) in the region of the Strait of Gibraltar, or L-monomorphic (with only L plants) in the inland of the Iberian Peninsula. This variation correlates with the most common floral visitors, be these primarily long-tongued and short-tongued pollinators respectively, a rare condition in Mediterranean plants. The maintenance of S-flowers relies on long-tongued insects, as only those deliver pollen to short-styled stigmas. Narcissus flowers present a long and narrow tube, at the bottom of which nectar accumulates, and a floral corona, which has been proposed as an important trait for the attraction of pollinators. Here we tested the importance of the corona on the pollination of L and S...
Plant biology (Stuttgart, Germany), Jan 4, 2017
Plant populations invading new environments might compromise their fitness contribution to the ne... more Plant populations invading new environments might compromise their fitness contribution to the next generation, owing to the lack of native specialist pollinators and/or potential mates. Thus, changes in plant mating system and traits linked to it are expected in populations colonising new environments where selection would favour selfing and floral traits that maximise reproductive output. To test this, we studied native (Mexico) and non-native (Spain) populations of the obligate sex reproducing annual weed Datura stramonium. Flower size, herkogamy, total number of seeds per plant, number of visits by and type of pollinators, and inbreeding depression, were assessed in native and non-native populations. Finally, we measured phenotypic selection on corolla size and herkogamy in each population. Flower size and herkogamy showed wide and similar variation in both ranges. However, the largest average flower size was found in one non-native population whereas the highest average positiv...
Flora, 1990
Results: The project comes with an innovative design that was achieved through the aforementioned... more Results: The project comes with an innovative design that was achieved through the aforementioned methodology using the Araucoply material and solving the initial problem for which the project is made. Conclusions: Two arc options are made where the significant change is in the design of the joints that takes a tensegrity to another, this change is made in order to save material and facilitate the processing of the parts.
Quercus, 2004
Biblioteca de la Universidad Complutense de Madrid, Base de datos de artículos de revistas, ...
Forest Systems, Aug 1, 2003
El paisaje forestal mediterráneo que vemos en la actualidad es el resultado de la actuación del h... more El paisaje forestal mediterráneo que vemos en la actualidad es el resultado de la actuación del hombre y su gestión de los recursos a lo largo de la Historia (Le Houérou, 1981; McNeill, 1992; Marañón y Ojeda, 1998). Entre los procesos que han contribuido a la deforestación de la Cuenca Mediterránea, Thirgood (1981) ha destacado los siguientes: la transformación del bosque en cultivos y pastos, la explotación de ma-dera para la construcción de barcos, la extracción de combustible para uso doméstico o para la minería, las guerras e invasiones, los incendios y el sobrepastoreo. Los bosques del Rif, y en particular de la Península Tingitana (norte de Marruecos), han sufrido episodios intensos de perturbación que han sido más acentuados en la época reciente (Mikesell, 1960; Reille, 1977; Taiqui, 1997). La mayor parte de los bosques actuales de Marruecos son testigos de una explotación intensa, que se refleja en su estructura y composición. Excepcionalmente, los morabitos o «bosques sagrados» han sido respetados en señal de respeto hacia el santo musul
Proceedings. Biological sciences / The Royal Society, Aug 22, 2015
Many of the macroevolutionary processes that have shaped present-day phylogenetic patterns were c... more Many of the macroevolutionary processes that have shaped present-day phylogenetic patterns were caused by geological events such as plate tectonics and temporary land-bridges. The study of spatial patterns of phylogenetic diversity can provide insights into these past events. Here we focus on a western Mediterranean biodiversity hotspot located in the southern Iberian Peninsula and northwest Africa, two regions that are separated by the Strait of Gibraltar. We explore the spatial structure of the phylogenetic relationships within and across large-scale plant assemblages. Significant turnover in terminal lineages tends to occur between landmasses, whereas turnover in deep lineages tends to occur within landmasses. Plant assemblages in the western ecoregions of this hotspot tend to be phylogenetically overdispersed but are phylogenetically clustered on its eastern margins. We discuss our results in the light of potential scenarios of niche evolution (or conservatism) and lineage diver...
98 relevés représentatifs des massifs forestiers du nord du Maroc ont été réalisés. Les subéraies... more 98 relevés représentatifs des massifs forestiers du nord du Maroc ont été réalisés. Les subéraies sont les formations forestières les plus représentatives et les plus diversifiées dans l'aire d'étude. En effet, elles représentent une richesse spécifique et une richesse en taxons endémiques remarquables. Chez les formations forestières dominées par Quercus suber et Q. canariensis, l'altitude, la fertilité du sol et la perturbation anthropique jouent un rôle primordial dans la distribution des espèces. Cette distribution semble exprimer la dynamique de la végétation selon un gradient de conservation-perturbation. D'autres parts, la structure démographique des subéraies étudiées a montré un déficit évident de régénération naturelles.
Botanical Journal of the Linnean Society, 2015
Heterostyly and related polymorphisms (e.g. stigma-height dimorphism) have been used as model sys... more Heterostyly and related polymorphisms (e.g. stigma-height dimorphism) have been used as model systems for studying the origin and maintenance of plant population variability. Stigma-height dimorphism frequently occurs in Narcissus and is associated with a particular flower shape. In the present study, we describe a new, peculiar case of stigma-height dimorphism in Narcissus broussonetii, a species on the margin of the geographical distribution of the genus. We determined the stylar condition of N. broussonetii and its variation across populations, analyzed perianth morphology and its relationship with stylar variation, and compared this species with other stylar dimorphic species of the genus. We also studied the incompatibility system and pollination ecology of the species. Narcissus broussonetii is a style-dimorphic species, as suggested in early studies that were subsequently neglected, and displays unusual flower morphology, with a long floral tube and a virtual absence of a corona. The species shows a late-(ovarian) acting incompatibility system and crosses within and between morphs are fertile. We observed short-tongued diurnal and long-tongued nocturnal pollinators. Our findings confirm that the presence of the observed dimorphism across populations is most probably the result of the joint action of a nonheteromorphic incompatibility system, extremely long and narrow floral tubes, and a combined role of short-and long-tongued pollinators.