2025
Martínez, D. N.; de la Barrera, E.
Enzymatic activity responses to transport and low-temperature storage: implication for plant nitrogen metabolism studies Journal Article
In: Nitrogen, vol. 6, 2025, ISBN: 2504-3129.
Abstract | Links | BibTeX | Tags: disturbance, neotropical, nitrate reductase, nitrogen deposition, phosphorus, planetary boundaries, plant nutrition, tropical forest, urban ecology
@article{Martínez2025,
title = {Enzymatic activity responses to transport and low-temperature storage: implication for plant nitrogen metabolism studies},
author = {D. N. Martínez and E. de la Barrera},
url = {https://www.mdpi.com/2504-3129/6/1/5
https://agro.mx/wp-content/uploads/2025/01/077-Martinez-N-cold-enzymes.pdf},
doi = {10.3390/nitrogen6010005},
isbn = {2504-3129},
year = {2025},
date = {2025-01-16},
urldate = {2025-01-16},
journal = {Nitrogen},
volume = {6},
abstract = {Understanding how transport and storage conditions affect enzymatic activity is essential for accurate biomonitoring of nitrogen metabolism in plants. This study evaluated the effects of transport conditions and low-temperature storage on the enzymatic activities of nitrate reductase (NR), glutamine synthetase (GS), and phosphomonoesterase (PME) for Chloris gayana, Fraxinus uhdei, and Trifolium repens. Enzymatic activities were measured for leaf samples immediately after collection, after 18 h at room temperature, or after 18 h on ice. Additionally, samples were stored at –16°C or –45°C for up to 28 days. NR activity decreased to near-zero levels under all storage conditions, indicating that this enzyme is unsuitable for delayed analysis. In contrast, GS and PME activities showed species-dependent responses to storage, with increased activity ob-served for T. repens and C. gayana, potentially reflecting tissue degradation processes. F. uhdei exhibited greater stability in enzyme activities, suggesting a higher resilience to storage. These findings highlight the importance of minimizing storage time to preserve enzymatic integrity, particularly for NR, while providing insight into the potential for delayed analysis of GS and PME in specific species. This work offers practical recommendations for future biomonitoring ef-forts in nitrogen deposition studies.},
keywords = {disturbance, neotropical, nitrate reductase, nitrogen deposition, phosphorus, planetary boundaries, plant nutrition, tropical forest, urban ecology},
pubstate = {published},
tppubtype = {article}
}
Understanding how transport and storage conditions affect enzymatic activity is essential for accurate biomonitoring of nitrogen metabolism in plants. This study evaluated the effects of transport conditions and low-temperature storage on the enzymatic activities of nitrate reductase (NR), glutamine synthetase (GS), and phosphomonoesterase (PME) for Chloris gayana, Fraxinus uhdei, and Trifolium repens. Enzymatic activities were measured for leaf samples immediately after collection, after 18 h at room temperature, or after 18 h on ice. Additionally, samples were stored at –16°C or –45°C for up to 28 days. NR activity decreased to near-zero levels under all storage conditions, indicating that this enzyme is unsuitable for delayed analysis. In contrast, GS and PME activities showed species-dependent responses to storage, with increased activity ob-served for T. repens and C. gayana, potentially reflecting tissue degradation processes. F. uhdei exhibited greater stability in enzyme activities, suggesting a higher resilience to storage. These findings highlight the importance of minimizing storage time to preserve enzymatic integrity, particularly for NR, while providing insight into the potential for delayed analysis of GS and PME in specific species. This work offers practical recommendations for future biomonitoring ef-forts in nitrogen deposition studies.
2024
Pérez-Torres, L.; Yépez, E. A.; Lindig-Cisneros, R.; Moreno-Calles, A. I.; de la Barrera, E.
Indicadores para la evaluación de una dieta sostenible Proceedings Article
In: Ayón, J. M. Hérnandez; Balcorta, C Chapa; González, MA Bolaños; A, A López Serrano; Ibarra, AP (Ed.): Estado actual del conocimiento del ciclo del carbono y sus interacciones en México: Síntesis a 2024. , pp. 242-247, Programa Mexicano del Carbono & Universidad del Mar, 2024, ISBN: 2954–4882.
Abstract | Links | BibTeX | Tags: anthropocene, carbon, diet, nitrogen, planetary boundaries, sustainability, sustainable agriculture, sustainable development goals
@inproceedings{Pérez-Torres2024,
title = {Indicadores para la evaluación de una dieta sostenible},
author = {L. Pérez-Torres and E. A. Yépez and R. Lindig-Cisneros and A. I. Moreno-Calles and E. de la Barrera},
editor = {J.M. Hérnandez Ayón and C Chapa Balcorta and MA Bolaños González and A López Serrano A and AP Ibarra},
url = {https://agro.mx/wp-content/uploads/2025/01/076-Perez-Torres-etal-PMC-huella-alimentaria.pdf
},
isbn = {2954–4882},
year = {2024},
date = {2024-12-16},
urldate = {2024-12-16},
booktitle = {Estado actual del conocimiento del ciclo del carbono y sus interacciones en México: Síntesis a 2024. },
pages = {242-247},
publisher = {Programa Mexicano del Carbono & Universidad del Mar},
series = {Síntesis Nacionales},
abstract = {La intensificación de las prácticas agrícolas en respuesta a la creciente demanda de alimentos contribuye a la degradación ambiental. Los patrones alimentarios actuales agravan estos problemas, favoreciendo alimentos que son económicamente accesibles pero perjudiciales tanto para el medio ambiente como para la salud. Este trabajo propone un marco teórico para la evaluación de la sostenibilidad alimentaria, denominado "huella alimentaria", que integra indicadores ambientales, sociales y económicos. En particular, se destaca el impacto de las emisiones de gases de efecto invernadero, que juegan un papel clave en la degradación ambiental vinculada a la producción de alimentos. El marco se aplicó a las dietas Occidental, Mediterránea, Atlántica y Mexicana, y se comparó con una dieta Planetaria saludable. Se calculó un índice sintético de la Huella Alimentaria
para estas dietas, revelando que la dieta Occidental tiene el mayor impacto, lo que indica su insostenibilidad, mientras que la dieta Mexicana es la más sostenible. Este marco puede informar políticas y prácticas alimentarias sostenibles, para disminuir la huella alimentaria e impulsar la transición hacia dietas sostenibles, guiando tanto las decisiones individuales como las políticas
gubernamentales hacia un sistema alimentario más resiliente y responsable.},
keywords = {anthropocene, carbon, diet, nitrogen, planetary boundaries, sustainability, sustainable agriculture, sustainable development goals},
pubstate = {published},
tppubtype = {inproceedings}
}
La intensificación de las prácticas agrícolas en respuesta a la creciente demanda de alimentos contribuye a la degradación ambiental. Los patrones alimentarios actuales agravan estos problemas, favoreciendo alimentos que son económicamente accesibles pero perjudiciales tanto para el medio ambiente como para la salud. Este trabajo propone un marco teórico para la evaluación de la sostenibilidad alimentaria, denominado "huella alimentaria", que integra indicadores ambientales, sociales y económicos. En particular, se destaca el impacto de las emisiones de gases de efecto invernadero, que juegan un papel clave en la degradación ambiental vinculada a la producción de alimentos. El marco se aplicó a las dietas Occidental, Mediterránea, Atlántica y Mexicana, y se comparó con una dieta Planetaria saludable. Se calculó un índice sintético de la Huella Alimentaria
para estas dietas, revelando que la dieta Occidental tiene el mayor impacto, lo que indica su insostenibilidad, mientras que la dieta Mexicana es la más sostenible. Este marco puede informar políticas y prácticas alimentarias sostenibles, para disminuir la huella alimentaria e impulsar la transición hacia dietas sostenibles, guiando tanto las decisiones individuales como las políticas
gubernamentales hacia un sistema alimentario más resiliente y responsable.
para estas dietas, revelando que la dieta Occidental tiene el mayor impacto, lo que indica su insostenibilidad, mientras que la dieta Mexicana es la más sostenible. Este marco puede informar políticas y prácticas alimentarias sostenibles, para disminuir la huella alimentaria e impulsar la transición hacia dietas sostenibles, guiando tanto las decisiones individuales como las políticas
gubernamentales hacia un sistema alimentario más resiliente y responsable.
2022
de la Barrera, E.
The role of CAM ecophysiology in the Anthropocene Journal Article
In: Acta Horticulturae, vol. 1343, pp. 267-281, 2022.
Abstract | Links | BibTeX | Tags: anthropocene, arid, arid agriculture, atmospheric pollution, biomonitors, climate change, environmental productivity index, food security, nitrogen, nitrogen deposition, planetary boundaries
@article{delaBarrera2022,
title = {The role of CAM ecophysiology in the Anthropocene},
author = {E. de la Barrera},
url = {https://agro.mx/wp-content/uploads/2022/09/071-delaB-CAM-Anthropocene.pdf},
doi = {10.17660/ActaHortic.2022.1343.35},
year = {2022},
date = {2022-09-19},
urldate = {2022-09-19},
journal = {Acta Horticulturae},
volume = {1343},
pages = {267-281},
abstract = {Human impact on the planet is such that geologists have acknowledged the start of a new geological epoch, the Anthropocene, which is characterized by an environmental emergency with multiple open fronts such as climate change, biodiversity loss, decreased fresh water availability, alterations to the nitrogen cycle, and chemical pollution. Activities such as food production and the increasing aggregation of people in urban areas are simultaneously major drivers and vulnerable points of such environmental change. For example, climate change represents a major threat to food production, considering that a reduction of annual precipitation, in addition to temperature increases, is likely to occur especially in tropical agricultural regions. The use of CAM crops has been recognized as a useful strategy for climate change adaptation, owing to their tolerance of high temperatures and their inherently high water use efficiency. The potential performance of Opuntia ficus-indica and Agave tequilana is modeled as an application of the Environmental Productivity Index for identifying potential areas for cultivation under climate change. Regarding alterations to the nitrogen biogeochemical cycle, CAM epiphytes can be useful to characterize environmental pollution in tropical environments, especially when electrochemical monitoring networks are lacking. Indeed, CAM epiphytes are particularly promising to characterize the prevalent levels of heavy metals, persistent organic pollutants and, especially, nitrogen deposition. This is illustrated with the use of the orchid Laelia speciosa and the bromeliad Tillandsia recurvata as biomonitors of atmospheric nitrogen deposition. From fundamental research on the mechanisms behind plant responses to environmental change to applications in agriculture and biomonitoring, CAM ecophysiology will be essential in the Anthropocene.},
keywords = {anthropocene, arid, arid agriculture, atmospheric pollution, biomonitors, climate change, environmental productivity index, food security, nitrogen, nitrogen deposition, planetary boundaries},
pubstate = {published},
tppubtype = {article}
}
Human impact on the planet is such that geologists have acknowledged the start of a new geological epoch, the Anthropocene, which is characterized by an environmental emergency with multiple open fronts such as climate change, biodiversity loss, decreased fresh water availability, alterations to the nitrogen cycle, and chemical pollution. Activities such as food production and the increasing aggregation of people in urban areas are simultaneously major drivers and vulnerable points of such environmental change. For example, climate change represents a major threat to food production, considering that a reduction of annual precipitation, in addition to temperature increases, is likely to occur especially in tropical agricultural regions. The use of CAM crops has been recognized as a useful strategy for climate change adaptation, owing to their tolerance of high temperatures and their inherently high water use efficiency. The potential performance of Opuntia ficus-indica and Agave tequilana is modeled as an application of the Environmental Productivity Index for identifying potential areas for cultivation under climate change. Regarding alterations to the nitrogen biogeochemical cycle, CAM epiphytes can be useful to characterize environmental pollution in tropical environments, especially when electrochemical monitoring networks are lacking. Indeed, CAM epiphytes are particularly promising to characterize the prevalent levels of heavy metals, persistent organic pollutants and, especially, nitrogen deposition. This is illustrated with the use of the orchid Laelia speciosa and the bromeliad Tillandsia recurvata as biomonitors of atmospheric nitrogen deposition. From fundamental research on the mechanisms behind plant responses to environmental change to applications in agriculture and biomonitoring, CAM ecophysiology will be essential in the Anthropocene.
2021
Alcántara-Plazola, J. J.; de la Barrera, E.
Quantification of embedded phosphorus in Mexican agriculture Journal Article
In: Sustainable Production and Consumption, vol. 28C, pp. 824-828, 2021, ISSN: 2352-5509.
Abstract | Links | BibTeX | Tags: agriculture, embedded phosphorus, food security, phosphorus, planetary boundaries, telecoupling
@article{Alcántara-Plazola2021,
title = {Quantification of embedded phosphorus in Mexican agriculture},
author = {J. J. Alcántara-Plazola and E. de la Barrera},
url = {https://www.sciencedirect.com/science/article/abs/pii/S2352550921002104},
doi = {10.1016/j.spc.2021.07.011},
issn = {2352-5509},
year = {2021},
date = {2021-07-14},
journal = {Sustainable Production and Consumption},
volume = {28C},
pages = {824-828},
abstract = {Phosphorus is an essential element for agricultural production, and for life in general, whose availability as a mineral is geographically restricted. Considering that Mexico is a major contributor to the global flow of water embedded in agricultural commodities, it is likely that this country is also a major exporter of embedded phosphorus. Thus, we quantified the embedded phosphorus for the 38 major crops produced in Mexico from 1980 to 2015, which were grouped into forages, fruits and vegetables, cereals, legumes, and cash crops. The total phosphorus extracted was 4.4 × 106 tonnes for an agricultural production of 5,844 × 106 tonnes, which respectively increased by 86% and 145% over 35 years. Food crops, i.e., cereals, fruits and vegetables, and legumes, accounted for 44% of the total phosphorus extracted, forages for 38%, and cash crops for 18%. Forage production exhibited a substantial increase since 1995, becoming the largest phosphorus extractor by 2000. Our estimation of embedded phosphorus is susceptible of utilization in other countries and is a first step to estimate a country's phosphorus balance, which is necessary to understand the magnitude of the anthropogenic alteration of a biogeochemical cycle that is essential for the maintenance of life on earth.},
keywords = {agriculture, embedded phosphorus, food security, phosphorus, planetary boundaries, telecoupling},
pubstate = {published},
tppubtype = {article}
}
Phosphorus is an essential element for agricultural production, and for life in general, whose availability as a mineral is geographically restricted. Considering that Mexico is a major contributor to the global flow of water embedded in agricultural commodities, it is likely that this country is also a major exporter of embedded phosphorus. Thus, we quantified the embedded phosphorus for the 38 major crops produced in Mexico from 1980 to 2015, which were grouped into forages, fruits and vegetables, cereals, legumes, and cash crops. The total phosphorus extracted was 4.4 × 106 tonnes for an agricultural production of 5,844 × 106 tonnes, which respectively increased by 86% and 145% over 35 years. Food crops, i.e., cereals, fruits and vegetables, and legumes, accounted for 44% of the total phosphorus extracted, forages for 38%, and cash crops for 18%. Forage production exhibited a substantial increase since 1995, becoming the largest phosphorus extractor by 2000. Our estimation of embedded phosphorus is susceptible of utilization in other countries and is a first step to estimate a country's phosphorus balance, which is necessary to understand the magnitude of the anthropogenic alteration of a biogeochemical cycle that is essential for the maintenance of life on earth.
Martínez, D. N.; Díaz-Álvarez, E. A.; de la Barrera, E.
Selecting biomonitors of atmospheric nitrogen deposition: guidelines for practitioners and decision makers Journal Article
In: Nitrogen, vol. 2, no. 3, pp. 308-320, 2021, ISSN: 2504-3129.
Abstract | Links | BibTeX | Tags: atmospheric pollution, environmental indicators, environmental management, planetary boundaries, public health, public policy
@article{Martínez2021b,
title = {Selecting biomonitors of atmospheric nitrogen deposition: guidelines for practitioners and decision makers},
author = {D. N. Martínez and E. A. Díaz-Álvarez and E. de la Barrera },
url = {https://www.mdpi.com/2504-3129/2/3/21},
doi = {10.3390/nitrogen2030021},
issn = {2504-3129},
year = {2021},
date = {2021-07-12},
journal = {Nitrogen},
volume = {2},
number = {3},
pages = {308-320},
abstract = {Environmental pollution is a major threat to public health and is the cause of important economic losses worldwide. Atmospheric nitrogen deposition is one of the most significant components of environmental pollution, which, in addition to being a health risk, is one of the leading drivers of global biodiversity loss. However, monitoring pollution is not possible in many regions of the world because the instrumentation, deployment, operation, and maintenance of automated systems is onerous. An affordable alternative is the use of biomonitors, naturally occurring or transplanted organisms that respond to environmental pollution with a consistent and measurable ecophysiological response. This policy brief advocates for the use of biomonitors of atmospheric nitrogen deposition. Descriptions of the biological and monitoring particularities of commonly utilized biomonitor lichens, bryophytes, vascular epiphytes, herbs, and woody plants, are followed by a discussion of the principal ecophysiological parameters that have been shown to respond to the different nitrogen emissions and their rate of deposition.},
keywords = {atmospheric pollution, environmental indicators, environmental management, planetary boundaries, public health, public policy},
pubstate = {published},
tppubtype = {article}
}
Environmental pollution is a major threat to public health and is the cause of important economic losses worldwide. Atmospheric nitrogen deposition is one of the most significant components of environmental pollution, which, in addition to being a health risk, is one of the leading drivers of global biodiversity loss. However, monitoring pollution is not possible in many regions of the world because the instrumentation, deployment, operation, and maintenance of automated systems is onerous. An affordable alternative is the use of biomonitors, naturally occurring or transplanted organisms that respond to environmental pollution with a consistent and measurable ecophysiological response. This policy brief advocates for the use of biomonitors of atmospheric nitrogen deposition. Descriptions of the biological and monitoring particularities of commonly utilized biomonitor lichens, bryophytes, vascular epiphytes, herbs, and woody plants, are followed by a discussion of the principal ecophysiological parameters that have been shown to respond to the different nitrogen emissions and their rate of deposition.