Evaluación de la tolerancia al cobre de dos poblaciones de Oenothera picensis Phil. subsp. picensis (Onagraceae)

Oenothera picensis Phil. subsp. picensis can grow in soils that have been contaminated with copper from the metal smeltingindustry in central Chile, presenting characteristics that make it a candidate for phytoremediation processes. In order toknow the real tolerance and capacity for copper extraction and to identify whether this characteristic is present solelyin the exposed population, a hydroponic test was carried out using two populations of O. picensis, originated from LosMaitenes and Maitencillo, areas with high and normal Cu concentrations in the soil, respectively. The plants were exposedto copper concentration in solution between 0 and 0.16 mM, for one month. The plants presented symptoms of toxicityat 0.04 mM of Cu in the solution, without significant differences in the tolerance of both populations. The shoot copperconcentrations observed in O. picensis reached the maximum of 1660±857 mg kg-1, in the treatment of 0.16 mM of Cu inthe solution. However, in this treatment, the plant presented severe toxicity symptoms. Thus, it is not possible to classify itas a hyperaccumulating species.Oenothera picensis Phil. subsp. picensis puede crecer en suelos contaminados por cobre proveniente de una fundición demetal en Chile central, y presenta características que la hacen candidata para procesos de fitorremediación. Para conocerla tolerancia real y capacidad de extracción de cobre, y si ello ocurre sólo en la población expuesta, se realizaron ensayoshidropónicos utilizando dos poblaciones de O. picensis, provenientes de los sectores Los Maitenes y Maitencillo, áreascon concentraciones altas y normales de Cu en el suelo, respectivamente. Las plantas fueron expuestas a concentracionesde cobre entre 0 y 0,16 mM en la solución, por un período de 1 mes. Las plantas mostraron síntomas de toxicidad a unaconcentración de 0,04 mM de Cu en la solución, sin diferencias significativas en la tolerancia de ambas poblaciones. Lasconcentraciones de cobre foliar observadas en O. picensis alcanzaron un máximo de 1660±857 mg kg-1, en el tratamientode 0,16 mM de Cu en la solución. Sin embargo, en este tratamiento, la planta presentó severos síntomas de toxicidad. Porlo tanto, no es posible clasificarla como una especie hiperacumuladora

Modelo predictivo de la distribución espacial de cobre en suelos agrícolas de la cuenca del Río Aconcagua, Chile

Se presenta una propuesta metodológica que permitirá, sin necesidad de realizar un muestreo en terreno ni análisis de laboratorio, pronosticar preliminarmente la distribución del cobre en los suelos de una cuenca hidrológica. Esta información será de utilidad para posteriormente diseñar una estrategia de muestreo representativa y focalizada en áreas con potencialidad de contener el elemento en cuestión. Se espera que esta propuesta signifique finalmente un ahorro de recursos, tanto materiales como humanos. El modelo propuesto se fundamenta en la localización espacial y posterior clasificación de las eventuales fuentes contaminantes. El modelo fue sometido a prueba mediante el pronóstico de las concentraciones de cobre en los suelos agrícolas de la cuenca del Río Aconcagua. Finalmente, los resultados pronosticados fueron comparados con los resultados de un muestreo real efectuado en la cuenca. El pronóstico se validó en un 65% respecto a la distribución espacial y concentraciones de cobre observadas en la realidad

Biodegradable chelate enhances the phytoextraction of copper by Oenothera picensis grown in copper-contaminated acid soils

Oenothera picensis plants grow in the acid soils contaminated by copper smelting in the coastal region of central Chile. We evaluated the effects of the biodegradable chelate MGDA on copper extraction by O. picensis and on leaching of copper through the soil profile, using an ex situ experiment with soil columns of varying heights. MGDA was applied in two doses, one month apart, at concentrations of 0 (control), 2, 6 and 10 mmol plant-1. MGDA application significantly increased biomass production and foliar concentration, permitting an effective increase in copper extraction, from 0.09 mg plant-1 in the control, to 1.3 mg plant-1 in the 6 and 10 mmol plant-1 treatments. With 10 mmol plant-1 of MGDA, the copper concentration in the leachate from the 30 cm columns was 20 times higher than in the control. For the 60 cm columns, copper concentration was 2 times higher than the control. It can be concluded that at increased soil depths, copper leaching would be minimal and that MGDA applications at the studied concentrations would not pose a high risk for leaching into groundwater. It can thus be stated that applications of MGDA are an effective and environmentally safe way to improve copper extraction by O. picensis in these soils

Prosociality and proenvironmentalism as components of sustainable behavior: toward an integrated approach to sustainability education

The concept of sustainable development includes three interdependent and mutually reinforcing pillars: economic development, social development and environmental protection [1]. Below, we provide arguments that proenvironmentalism and prosociality are components of a broader behavior, named “sustainable behavior”. We thus suggest that traditional emphasis of environmental education on protecting and/or preserving the environment may be reinforced with prosocial education. Such a combined educational approach can promote sustainable behavior, contributing to multi- and inter-disciplinary efforts to create an ecologically, socially and perhaps even economically sustainable society. Proenvironmental behavior is defined as actions which contribute towards environmental preservation and/or conservation [2]. In turn, prosocial behavior is defined as voluntary behavior intended to benefit others or promote harmonious relationship with others [3], [4]. Previous studies demonstrate correlations between proenvironmental and prosocial behavior [5], [7]. For example, Joireman et al. [8] found an association between prosociality and the use of public transport, which has a lower impact on the environment, in comparison to the use of individual motorized transport. Furthermore, [5] and [6] empirically demonstrated that prosociality and proenvironmentalism are components of a broader behavior, which they called “sustainable behavior” since it includes actions aimed at protecting both the natural and the human (social) environments. With regards to the environmental aspects of sustainability, some authors suggest that “environmental problems” are actually problems of human behavior [9]. The first definition of environmental education [10] emphasized the importance of educating the general public about taking action to solve environmental problems. Based on the in-depth analysis of [11], the main emphasis of environmental education is limited to the protection and/or preservation of the environment, while education for sustainable development (or sustainability education) is usually defined as a tool for achieving sustainable development [12]. Prosocial education aims at educating people to share with acquaintances and strangers, to make friends, to work cooperatively, and to develop a sense of self as a moral person [13]. The term “prosocial education” is actually an umbrella concept since it conceptually overlaps with other terms, such as soft-skills development, social-emotional learning, whole child education, service learning, civic education, character education and moral education [2]. Schonert-Reichl & O’Brien [14] reviewed several social-emotional learning programs that have empirical evidence to support their effectiveness, demonstrating that it is possible to promote prosocial behavior through creating a prosocial classroom environment, which emphasizes caring for others, mutual respect and cooperation. Prosocial education could help to gradually bridge this gap of “otherness,” with the aim of helping students overcome alienation, emerging from oneself towards the other by learning to be concerned for the other as we are concerned for ourselves [15]. Since on the individual level prosocial and proenvironmental behaviors are parts of the same behavior, prosocial and environmental educational approaches can reinforce each other. Thus, we suggest that the traditional emphasis of environmental education on protecting and/or preserving the environment could be reinforced with prosocial education. Such a combined educational approach would promote sustainable behavior, contributing to multi- and inter-disciplinary efforts to create an ecologically and socially sustainable society. With regard to the economic aspect of sustainable development, some leading economists [16], [17] claim that the current economic system requires the installation of a more social aspect in order to manage today’s interconnected reality. To prevent the enormous damage that is caused to the community as a whole by behavior triggered by fierce economic competition [18], there is a need to react educationally. One possible reaction may be to promote prosocial educational approaches that aim to increase our sense of responsibility towards others. Since the economy is considered a reflection of our relationships [19], the economy might perhaps adjust itself if we change our perception of others and our sensitivity toward others by promoting prosocial educational approaches. One of the biggest paradoxes of contemporary reality is that on the one hand, people, corporations and nations are being increasingly tied together in complex global networks, but on the other, human interactions within these networks are becoming more fragmented, alienated and in many cases motivated by self or local interest [19]. Perhaps the collision between these two opposite tendencies is one of the main reasons for the escalation of the financial crisis worldwide. As the contradiction between our interconnectedness and the nature of human interactions widens – so widens the crisis [20]. In summary, prosocial education could not only reinforce environmental education but also contribute significantly to financial and economic sustainability, by cultivating in students a more socially oriented attitude to the world. This in turn can result in sustainable behavior in local and global social networks [21], [22]. Such an approach is aligned with the proposals of UNESCO [23] that promote the Decade of Education for Sustainable Development, stressing that education must provide specific skills, such as learning to live together

Toward an Integrated Approach to Environmental and Prosocial Education

Environmental education programs neglect the aspect of prosocial behavior as a correlate of pro-environmental behavior. This article examines the possible benefits of increasing the emphasis on prosocial behavior as a way to reinforce environmental education. In our study, prosocial behavior was positively related to pro-environmental behavior (r = 0.34, p < 0.001), and even a combined scale consisting of prosocial and pro-environmental behavior items showed an acceptable reliability (separation reliability = 0.82, at the level of the separated scales), which implies that prosocial and pro-environmental behaviors are a similar class of behavior. We can assume that the two underlying propensities (prosocial behavior and pro-environmentalism) are probably only two facets of an overarching common propensity that supports both kinds of behavior. Therefore, promoting one facet will, through its relationship with the other facet, also foster the respective other facet. Even more so, it might be most effective to relate to both propensities equally

Clonal propagation of the avocado: effects of the rooting step on graft union formation and development

The etiolation and layering technique that is used on avocados has two critical steps, namely, the rooting of clonal rootstock and graft union formation between the commercial variety and clonal rootstock. This study analyzed the rooting step of the clonal rootstock regarding its influence on graft union formation and development. The optimum times for grafting the commercial variety onto clonal avocado rootstock were determined under two greenhouse conditions, heating and no heating. The results showed that under greenhouse conditions without heating, there was higher survival (%) in plants that were grafted 60 days after the rooting steps in the clonal scion, and, in the experiments in a heated greenhouse, the highest survival rate (%) was observed in plants that were grafted 15 days after the rooting treatments. For both assays, the lowest survival rate was observed for grafts performed 30 days after the wounding and auxin application process. In histological cross sections of rootstocks at the wounding zone and in auxin treatments, a large number of emerging adventitious roots were developed at 30 days.La técnica de etiolación y acodo utilizada en palto presenta dos etapas críticas: el enraizamiento del portainjerto clonal y el prendimiento del injerto entre la variedad comercial y el portainjerto clonal. En este estudio se evaluó la influencia de la fase de enraizamiento del portainjerto clonal sobre el prendimiento y desarrollo del injerto. Definiendo los momentos óptimos para realizar la injertación de la variedad comercial sobre el portainjerto clonal de palto, en dos condiciones de invernadero con y sin calefacción. Los resultados mostraron para las condiciones de invernadero sin calefacción, mayor prendimiento (%) en plantas injertadas a los 60 días después de los pasos de enraizamiento en la púa clonal, mientras que en el ensayo realizado en invernadero calefaccionado el mayor prendimiento (%) se observó en plantas injertadas a los 15 días después de realizados los tratamientos de enraizamiento. Para ambos ensayos, el menor prendimiento (%) se observó en plantas injertadas a los 30 días después de realizado el lesionado y la aplicación de auxinas. En cortes histológicos realizados al portainjerto, en la zona del lesionado y aplicación de la mezcla auxínica, a los 30 días, se observó gran cantidad de raíces adventicias emergiendo