Figure 1 - uploaded by Mariana Hernandez
Content may be subject to copyright.
The Pedregal de San Ángel Ecological Reserve (REPSA) in Mexico City (Distrito Federal), Mexico. Orthophotomap modified from de la Fuente (2005).
Source publication
Fire causes a reduction of plant cover due to the death of several structures, especially of those that are not isolated from high temperatures; such as seeds and fruits. After a disturbance the availability of diaspores is crucial for the recovery of the community. This work studied the composition and abundance of the seed rain in the xerophytic...
Contexts in source publication
Context 1
... site. The Ecological Reserve "El Pedregal de San Ángel" hosts a xerophytic shrubland and is located in southwest Mexico City (19°18'31"-19°19'17" N, 99°10'20"-99°11'52" W) at an altitude of 2 300 m. It covers a total area of 237.3 ha (171 ha correspond to a nucleus area and 66 ha to a buffer area) (de la Fuente, 2005) (Fig. 1). The climate of the REPSA, including the university campus, in general is temperate sub humid, type Cb (w1)(w) (García, 1988), with a mean annual temperature of 15.5° C and a mean annual precipitation of 835 mm. There is a marked rainy season from June to October and a dry season from November to ...
Context 2
... have been reported for this reserve (CastilloArgüero et al., 2009). Several authors have suggested that the high diversity found here is closely related to a peculiar environmental heterogeneity generated by a lava flow from the Xitle volcano some 2000 years ago and its posterior cooling off (Martin del Pozzo, 1995;CastilloArgüero et al., 2004) (Fig. 1). Families such as Asteraceae, Poaceae, and Fabaceae have the greatest number of species in the community. Most are perennial, with herbaceous and shrubby species as dominant (Castillo-Argüero et al., ...
Citations
... The first group comprised empirical descriptions of the ecological interactions involving the model's variables and was used for the construction of the reaction network and hence the mathematical model (Rzedowski 1954;Hernández Islas, 1984;Soberón-M. et al., 1991;Segura-Burciaga and Martínez-Ramos, 1994;Segura-Burciaga, 1995;Cano-Santana and Meave, 1996;Olvera Carrillo, 2001;Segura-Burciaga and Meave, 2001;Mendoza Hernández, 2002, 2003Rodríguez de la Vega, 2003;Flores Vázquez, 2004;Camacho Altamirano, 2007;Antonio-Garcés et al., 2009;Castillo-Argüero et al., 2009;Valverde and Chávez, 2009;Martínez-Orea et al., 2012;Mendoza-Hernández et al., 2013;Santillán Carvantes, 2013). The second group included longitudinal demographic monitoring of the densities of the three species and were used for parameterizing the mathematical model. ...
Data-based modelling of the dynamic behaviour of ecological communities is a big challenge in systems ecology and conservation biology. Implementing such models to forecast future scenarios is key for supporting decisionmaking in ecological reserves, given the multiple disturbances threatening their future. Using demographic and dynamic data for three tree (or tree-like) species from the Pedregal de San ´Angel Ecological Reserve (Mexico City, Mexico), we constructed a family of dynamical models (using systems of ordinary differential equations) to reconstruct their dynamic interactions. The first two models considered two native species (Pittocaulon praecox and Buddleja cordata), with either antagonistic or cooperative interactions between them. These species have been considered ecosystem engineers playing different roles in the system and determining several community attributes. These models predict the transition from a stable steady state dominated by P. praecox (as reported in the 1950s) to the current community whose structure is apparently shifting to an alternative stable state dominated by B. cordata. The second pair of models additionally incorporate the invasive tree Eucalyptus camaldulensis, which exerts negative effects on all native plant species. The prediction of these models is an E. camaldulensis-dominated state with the exclusion of the native species from the reserve, provided this invasive species follows current population growth trends, without external intervention to check this process. Bifurcation analysis of this latter model allowed us to rationally design optimal intervention strategies that could potentially divert the trajectory from converging to an E. camaldulensis-only configuration into the stable coexistence of the native species. For the two-species and three-species models we made two versions, one with only competitive interactions and another one including a facilitation interaction between B. cordata and P. praecox. This analysis shows that facilitation is a requirement to achieve stable coexistence between the two native species, even in the presence of E. camaldulensis. The models constructed here, which integrate multiple data sources, help clarify conflicting empirical information regarding potential ecological mechanisms, and allow making predictions for strengthening the future management and E. camaldulensis control programs before its effects irreversibly modify the functioning and biodiversity of the biotic community protected in the reserve.
... This reserve covers 237.3 ha, and is inhabited by least 1,821 species of different tax, including 130 birds, 20 reptiles and 33 mammals among others (CASTILLO-ARGUERO et al., 2007;ESTAÑOL-TECUATL & CANO-SANTANA, 2017). Buildings and wide avenues are surrounding this reserve and it has been constantly affected by irregular garbage deposition and invasion of feral fauna, among other problems (MARTÍNEZ-OREA et al., 2012). With respect to the feral fauna, it has been particularly worrisome with the presence of antibody titers in dogs against rabies, Toxoplasma gondii, and parvovirus (SUZÁN & CEBALLOS, 2005), suggesting an important risk for public and ecosystem health. ...
Free-ranging and feral dogs represent a group of unattended companion animals. They impact wild animal populations by predating native species, displacing predators and introducing exotic pathogens. The aim of this work was to describe the molecular occurrence of Rickettsia, Ehrlichia, Anaplasma, Mycoplasma and Bartonella in feral dogs. The study was carried out in the last relict of a protected area in Mexico City. Blood clots samples from 19 dogs were obtained and analyzed for detection of specific fragments of the 16S-rRNA gene for Anaplasma, Ehrlichia and Mycoplasma and citrate synthase (gltA) for Bartonella and Rickettsia. Our results showed that DNA from three bacteria species (Bartonella vinsonii subsp. berkhoffii, Ehrlichia canis and Mycoplasma haemocanis) was present with frequencies ranging from 5.3 to 15.8%. This is the first record of B. vinsonii subsp. berkhoffii and M. haemocanis in dogs from México, and also the first finding of Ehrlichia canis in Mexico City. It is important to perform surveillance of feral dog populations in order to identify the impact of these pathogens on wild animal populations and Public Health in order to establish prevention and protection programs.
... Su alta presencia se debe a que se desarrolla bien sobre lutita y caliza, y es pionera en ecosistemas degradados por actividades mineras, debido a sus sistemas de raíces profundas, las cuales pueden establecerse sobre suelos pobres y altamente rocosos. Otra estrategia evolutiva es su gran cantidad de semillas pequeñas con cerdas plumosas, estas últimas características de diásporas con dispersión pogonócora (Martínez et al., 2012), que les confiere una alta eficiencia a la dispersión en largas distancias (Cain et al., 2012). Asimismo, Brickellia veronicifolia pierde la parte aérea en los períodos críticos del año (hemicriptófita), lo que le permite adaptarse a las condiciones de carencia de agua y escapar de factores que ponen en peligro su supervivencia en estos hábitats (Franco, 2005). ...
Antecedentes y Objetivos:
Las estrategias de restauración tienen como objetivo favorecer la recuperación de los ecosistemas alterados, para lograr el restablecimiento de su estructura y funcionamiento naturales. La presente investigación evaluó la abundancia, dominancia, frecuencia y diversidad de especies en tres áreas de matorral espinoso tamaulipeco.
Métodos:
Dos áreas fueron sometidas durante siete años (2000-2006) a procesos de aprovechamiento a cielo abierto. A una se le aplicaron técnicas de restauración y a la otra no, y se compararon con un área en la que no se tiene perturbación registrada llamada área referencia. En el año 2013 se establecieron 36 sitios de muestreo, 12 por cada una de las áreas cuyas dimensiones fueron de 100 m² (10 x 10 m), en las que se registraron los atributos ecológicos de las comunidades vegetales establecidas.
Resultados clave:
En el área sin restaurar no se registró regeneración de la comunidad vegetal. La riqueza específica (S), índice de Margalef (DMg) e índice de Shannon (H') mostraron diferencias significativas entre el área restaurada y la de referencia (Valores medios S 4.75 y 8.25, DMg 0.87 y 1.80, H' 0.7 y 1.54, respectivamente), mientras que las variables de densidad, área de copa e índice de Pretzsch (A) no mostraron diferencias.
Conclusiones:
Se concluye que la técnica de restauración activa, la cual consiste en el depósito de material rocoso y edáfico en el área, y su exclusión de actividades productivas, generan condiciones favorables para que la comunidad vegetal del matorral espinoso tamaulipeco se establezca teniendo similitud en la densidad y área de copa a un área de referencia en siete años.
... Although the three vegetation types in our study are contiguous within a temperate forest, they host different communities and are characterized by their own composition and characteristic variations in altitude, slope, aspect, and canopy cover (Á vila 2002, Santibáñ ez 2009, Gutiérrez 2011, Castro 2013); these differences have proven to affect regeneration sources (Rees et al. 2000). Another source of variation is related to the fact that our study site is a forest immersed in a city where anthropogenic disturbance has resulted in a matrix of mature forest, secondary vegetation patches, and deforested sites (Á vila 2002, Calderó n and Rzedowski 2005, Martínez et al. 2012); this can also modify the quantities and composition of seed rain (Cheptou et al. 2008). These spatial variations in the abundance and richness of regeneration sources (i.e., seed rain) characterize the functional variability in a community (Rees et al. 2000), and this variability is also generally linked to seasonality. ...
... The propagule pressures of native and of introduced weed species in the seed rain could have implications for natural regeneration if they are capable of storing their seeds in a permanent seed bank (Martínez et al. 2012). In this study, weed species were present in the following proportions: 24% in oak forest, 25% in fir forest, and 17% in pine forests. ...
The regeneration of temperate forests is important, especially for those located in urban areas. Sources of propagules, such as seed rain, shape the structure and composition of systems where the availability of diaspores from forest species contribute to both local biodiversity and ecosystem services; these elements are crucial in Mexico City. Over the course of one year, we estimated natural regeneration potential through an analysis of the seed rain deposited in traps that were placed at soil level in plots in three vegetation types: oak, fir and pine forests. We addressed the following questions: Do abundance, density, species composition and diversity of seed rain differ among vegetation types and seasons? How similar is the seed rain to the standing vegetation? Is seed rain a potential source for the natural regeneration of temperate forests? The results showed that the abundance and density of seeds were significantly higher for oak and fir forests due to a higher number of herb, shrub, and tree species in the standing vegetation. The most abundant species in the total seed rain was Ageratina enixa (B.L. Rob.) R.M. King & H. Rob. (12%), but inside individual forest plots, the most abundant were Quercus rugosa Née (16%), Abies religiosa (Kunth) Schltdl. & Cham. (17.5%) and Pinus hartwegii Lindl. (41%). Diversity index values differed among vegetation types but not seasons. Most diaspores in the seed rain corresponded to native species (97%). The similarity between seed rain and the standing vegetation was 40%. In total, 62% of the species are anemochorous, as a result of the high number of Asteraceae species present, and endozoochory is the second most important (17%) dispersal syndrome. A slight asynchrony was observed between the peaks of anemochorous and zoochorous species.
... Su dispersión por viento favorece su transporte a larga distancia (Martínez et al., 2009). En esta categoría se incluye Buddleia cordata, característica de sitios de bosque templado en condiciones secundarias como terrenos deforestados y aledaños a zonas urbanas, presente en la lluvia y banco de semillas de la CRM y que se ha encontrado también (Martínez-Orea et al., 2012) en otros sistemas aledaños a grandes ciudades como matorrales xerófilos (Figura 4). ...
Los bosques templados mexicanos tienen una alta diversidad
de especies y endemismos, por lo que merecen atención
prioritaria en materia de conservación. El estudio de su regeneración
natural es determinante para entender los procesos
de remplazo de especies y para su restauración. Se analizó la
composición y abundancia de la lluvia y del banco de semillas
en la dos épocas del año (seca y lluviosa), con el propósito de
evaluar su contribución a la regeneración natural en bosques
templados (bosque de Quercus spp., de Abies religiosa y de Pinus
hartwegii) de la cuenca del río Magdalena (CRM). Particularmente
se cuantificaron la riqueza y cantidad de diásporas
en la lluvia de semillas, la riqueza y cantidad de plántulas
del banco de semillas, ambos se compararon entre sí y con la
composición de la vegetación en pie. La riqueza fue mayor en
la lluvia de semillas y se registró un aporte importante de especies
herbáceas, arbustivas y arbóreas características de bosque
templado. En el banco de semillas destacó la ausencia de
dos de las tres especies arbóreas más importantes en la zona
y abundaron las especies herbáceas de estadios sucesionales
tempranos. La menor similitud de especies se encontró entre el
banco de semillas y la vegetación en pie. Conocer el potencial
de regeneración natural en lluvia y banco de semillas permite
considerar ciertas especies para prescribir planes de manejo,
con el fin de producir condiciones de vegetación parecidas a
las originales del bosque templado.
... Su dispersión por viento favorece su transporte a larga distancia (Martínez et al., 2009). En esta categoría se incluye Buddleia cordata, característica de sitios de bosque templado en condiciones secundarias como terrenos deforestados y aledaños a zonas urbanas, presente en la lluvia y banco de semillas de la CRM y que se ha encontrado también (Martínez-Orea et al., 2012) en otros sistemas aledaños a grandes ciudades como matorrales xerófilos (Figura 4). Categoría B. Las especies arbustivas y arbóreas de frutos carnosos indican presencia de vertebrados que están asociados a zonas más conservadas y que las dispersan a distintas áreas: Como ejemplos figuran Phytolaca iccosandra, Solanum cervantesii, Cestrum anagyris, Prunus serotina, Sambucus nigra, nothus coeruleus y Fuchsia thymifolia, esta última indicadora de un buen estado de conservación pues habita sitios de bosque no perturbado, mientras que P. iccosandra y S. nigra son malezas nativas que se distribuyen en bosques templados en condiciones de disturbio (Rzedowski y Rzedowski, 2005), por lo que son especies tolerantes. ...
a regeneración natural es determinante en la conservación de un sis-tema y su estudio es básico para enten-der el remplazo de especies en una co-munidad (Vieira y Scariot; 2006). Exis-ten tres fuentes esenciales para la rege-neración natural: las semillas incorporadas y almacenadas en el banco del suelo o en la planta madre (seroti-nia), la entrada de propágulos a través de la lluvia de semillas y el rebrote de estructuras perennes aéreas o subterrá-neas (Young et al., 1987). 0378-1844/13/06/400-10 $ 3.00/0
... Although the three vegetation types in our study are contiguous within a temperate forest, they host different communities and are characterized by their own composition and characteristic variations in altitude, slope, aspect, and canopy cover (Á vila 2002, Santibáñ ez 2009, Gutiérrez 2011, Castro 2013); these differences have proven to affect regeneration sources (Rees et al. 2000). Another source of variation is related to the fact that our study site is a forest immersed in a city where anthropogenic disturbance has resulted in a matrix of mature forest, secondary vegetation patches, and deforested sites (Á vila 2002, Calderó n and Rzedowski 2005, Martínez et al. 2012); this can also modify the quantities and composition of seed rain (Cheptou et al. 2008). These spatial variations in the abundance and richness of regeneration sources (i.e., seed rain) characterize the functional variability in a community (Rees et al. 2000), and this variability is also generally linked to seasonality. ...
... The propagule pressures of native and of introduced weed species in the seed rain could have implications for natural regeneration if they are capable of storing their seeds in a permanent seed bank (Martínez et al. 2012). In this study, weed species were present in the following proportions: 24% in oak forest, 25% in fir forest, and 17% in pine forests. ...
Mexican temperate forests show a high species diversity as well as endemisms; therefore, the development of strategies for their conservation is a priority. Studies on their natural regeneration are crucial in order to understand the changes in species composition and for their restoration. The composition and abundance of seed rain and seed bank was analyzed during a year (dry and rainy seasons included), with the objective to evaluate their contribution to natural regeneration in temperate forests (Quercu spp., Abies religiosa and Pinus hartwegii forests) in the Magdalena river basin (MRB). Particularly, richness and quantity of diaspores in the seed rain, and the richness and quantity of seedlings in the seed bank were quantified. Comparison was carried out between them and also with respect to the extant vegetation. Richness resulted higher in the seed rain, with an important fraction of herbaceous, shrub and tree species characteristic of temperate forests. In the seed bank, two of the three main tree species in the area were absent, and there was a high abundance of herbaceous species characteristic of the early succession. The smallest similarity of species was found between the seed bank and the extant vegetation. Knowledge of the natural regeneration potential in the seed rain and in the seed bank allows for the consideration of certain species to be prescribed in management plans, with the aim to produce vegetation conditions similar to those of the original temperate forests.
Circular economy (CE) describes a sustainable alternative approach to the current linear economy system. It is a growing topic among scholars, practitioners, and decisionmakers; it encompasses several concepts related to sustainability and requires the synergy of multiple actors for success, including higher education institutions (HEIs) as one of the most relevant ones. Current CE is based mostly on experiences in Global North developed countries, where the concept has gained great attention and has already influenced policies and strategies. However, CE in Latin American countries (LA countries) have not yet received such attention. Thus, some “unique problems” may remain unattended, and efforts to attain a CE are more likely to fail. Likewise, the study shows how the role of HEIs in CE in LA countries has not yet been fully explored, as the literature on this topic is scarce. This paper aims to address the main research question: what is the role of HEIs in the transition to a CE in Latin American countries? For this, a two-fold methodology was performed: (i) a systematic review which allows understanding of the trends of CE research in LA and the extent of the HEIs involvement; and (ii) a narrative review, which provides insights into the state of the art of CE research (gaps, drivers, and barriers) in LA countries and how this relates to HEIs. This approach drew implications for the role of HEIs in the implementation of CE in LA countries. HEIs are key actors in this transition, contributing in several ways to the CE by collaborating with industry, assisting policy makers, building human and intellectual capital, supporting community engagement projects, influencing campus culture, linking with international CE networks, and promoting an inclusive CE discourse. This research contributes to the CE body of knowledge from a Latin-American Global South perspective by discussing the factors that aim to define the role of HEIs in the CE transition in LA countries.
The investigations of the effect of different habitat conditions on the composition of the seed rain and seedling pool were conducted in the years 2014 and 2015 in abandoned patches of Molinion caeruleae dominated by small-stature meadow taxa (patch I), tall-growing grasses (patch II), as well as shrubs and trees (patch III). Observations showed that along the successional gradient the seed rain and seedling pool diminishes. The prevalence of perennials and native taxa in the seed rain and seedling pool occurred in all the study sites. Moreover, in the propagule and seedling pools of all the patches hemicryptophytes and meadow taxa prevailed but their number decreased in successional sites. Also, the abundance of ruderal and grassland taxa decreased gradually, at expense of number of forest species. Zoochorous species prevailed in the seed rain and seedling pool of all patches. Number of hydrohorous species decreased in successional patches, while the abundance of species with other dispersal modes were similar. Irrespective of patch character, the species producing propagules with medium size dominated in the seed rain and seedling pools, whereas a significant decrease of number of small-seeded species was noticed only in the seedling pool. Despite the diminishing of the seed rain and seedling pool along the successional gradient, the gap creation might be a very effective way of active protection of Molinion caeruleae meadows. However, the gap colonisation requires permanent monitoring to avoid further spreading of undesired taxa. ARTICLE INFO Regular research paper Pol.
RESUMEN La restauración ecológica de espacios afectados por la explotación minera a cielo abierto debe tener como objetivo reconstruir y recuperar algunos atributos de los ecosis-temas naturales del entorno. La presente investigación tiene la finalidad de evaluar un área sujeta a la restauración activa en el matorral espinoso tamaulipeco, la cual estuvo bajo procesos de aprovechamiento a cielo abierto para la obtención de caliza, materia prima en los procesos de construc-ción. La técnica de restauración consistió en depositar material rocoso y edáfico en el área, proveniente de los desechos del aprovechamiento y excluirla de cualquier actividad productiva. Después de siete años se evaluó la comunidad vegetal mediante 2 sitios de muestreo de 00 m 2 (0 x 0 m). Con la información recabada se determina-ron a nivel especie los indicadores ecológi-cos de: abundancia, dominancia, frecuencia e índicie de valor de importancia, y a nivel comunidad los índice de Margalef (DMg) e índice de Shannon-Wiener (H´). Se regis-traron un total de 22 especies pertenecientes a 9 géneros y 3 familias. La familia con mayor presencia fue la Fabaceae, con cinco especies. La especie que presenta la mayor importancia en el área estudiada fue Bric-kellia veronicifolia cuyo índice de valor de importancia fue de 59.9%. A nivel comuni-dad, se registró un valor de H´deH´de .49 y un valor DMg de 3.2. Con esta investigación se concluye que las técnicas de restauración de depositar material rocoso y edáfico en el área y excluirla de cualquier actividad productiva generan condiciones favorables para que la comunidad vegetal del matorral espinoso tamaulipeco se establezca después de la actividad minera a cielo abierto. Palabras clave: restauración ecológica, referencia, restauración pasiva, minería, indicadores ecológicos.
