This page has only limited features, please log in for full access.

Dr. Carlos G.H. Diaz-Ambrona
Department of Agricultural Production, Research Group AgSystems, Innovation and Technology for Development Centre (itdUPM) (CEIGRAM), Higher Technical School of Agronomic, Food and Biosystems Engineering (ETSIAAB), Polytechnic University of Madrid (UPM), Madrid, Spain

Basic Info


Research Keywords & Expertise

0 Agroforestry
0 Climate Change
0 Sustainable Agriculture
0 System Dynamics
0 Dehesas

Fingerprints

Climate Change
Agroforestry
Sustainable Agriculture
System Dynamics

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 07 May 2021 in Entropy
Reads 0
Downloads 0

Estimates suggest that more than 70% of the world’s rangelands are degraded. The Normalized Difference Vegetation Index (NDVI) is commonly used by ecologists and agriculturalists to monitor vegetation and contribute to more sustainable rangeland management. This paper aims to explore the scaling character of NDVI and NDVI anomaly (NDVIa) time series by applying three fractal analyses: generalized structure function (GSF), multifractal detrended fluctuation analysis (MF-DFA), and Hurst index (HI). The study was conducted in four study areas in Southeastern Spain. Results suggest a multifractal character influenced by different land uses and spatial diversity. MF-DFA indicated an antipersistent character in study areas, while GSF and HI results indicated a persistent character. Different behaviors of generalized Hurst and scaling exponents were found between herbaceous and tree dominated areas. MF-DFA and surrogate and shuffle series allow us to study multifractal sources, reflecting the importance of long-range correlations in these areas. Two types of long-range correlation appear to be in place due to short-term memory reflecting seasonality and longer-term memory based on a time scale of a year or longer. The comparison of these series also provides us with a differentiating profile to distinguish among our four study areas that can improve land use and risk management in arid rangelands.

ACS Style

Ernesto Sanz; Antonio Saa-Requejo; Carlos Díaz-Ambrona; Margarita Ruiz-Ramos; Alfredo Rodríguez; Eva Iglesias; Paloma Esteve; Bárbara Soriano; Ana Tarquis. Generalized Structure Functions and Multifractal Detrended Fluctuation Analysis Applied to Vegetation Index Time Series: An Arid Rangeland Study. Entropy 2021, 23, 576 .

AMA Style

Ernesto Sanz, Antonio Saa-Requejo, Carlos Díaz-Ambrona, Margarita Ruiz-Ramos, Alfredo Rodríguez, Eva Iglesias, Paloma Esteve, Bárbara Soriano, Ana Tarquis. Generalized Structure Functions and Multifractal Detrended Fluctuation Analysis Applied to Vegetation Index Time Series: An Arid Rangeland Study. Entropy. 2021; 23 (5):576.

Chicago/Turabian Style

Ernesto Sanz; Antonio Saa-Requejo; Carlos Díaz-Ambrona; Margarita Ruiz-Ramos; Alfredo Rodríguez; Eva Iglesias; Paloma Esteve; Bárbara Soriano; Ana Tarquis. 2021. "Generalized Structure Functions and Multifractal Detrended Fluctuation Analysis Applied to Vegetation Index Time Series: An Arid Rangeland Study." Entropy 23, no. 5: 576.

Preprint content
Published: 28 April 2021
Reads 0
Downloads 0

Rangelands ecosystem comprises more than a third of the global land surface, sustaining key ecosystem services and livelihoods. Unfortunately, they suffer from severe degradation on a global scale. Tailored-monitoring of rangeland will allow us to improve their management and maintain their social-ecological systems.

MODIS data are commonly used to calculate Normalized Differenced Vegetation Index (NDVI) and NDVI anomaly (NDVIa) to monitor rangelands. In this study, we compare summary statistics and multifractal analysis to see if using complexity based tools improves our ability to differentiate land uses and types using remote sensing.

We collected time series using satellite data of MODIS (MOD09Q1.006) from 2000 to 2019. An area from southeastern Spain (Murcia province) of 6.25 Km2 was selected. This area comprised 132 pixels with a spatial resolution of 250 x 250 m2 and a temporal resolution of 8 days. This area includes irrigated and rainfed crops, shrubs and forested patches.

Multifractal detrended fluctuation analysis (MF-DFA) focuses on measuring variations of the moments of the absolute difference of their values at different scales. This allows us to use different multifractal exponent such as generalized Hurst exponent (H(q)), and its range (ΔH) to characterize the area. Here, we have selected H(1), H(2) and ΔH, to reflect variance, persistence and multifractality, respectively. Then, we compare them to the average, standard deviation and kurtosis of our NDVI and NDVIa series.

Our results indicate that MF-DFA, allow us to see more clearly the differences among the pixels than the summary statistics. Particularly H(1) and H(2) of NDVI reflects more precisely the vegetation profile and land uses of the selected area. On the other hand, NDVIa allows us to highlight those pixels where several uses occur, or some feature such as roads interact with NDVI. MF-DFA appears as a promising tool to classify and monitor rangelands.

Acknowledgements: The authors acknowledge the support of Project No. PGC2018-093854-B-I00 of the Ministerio de Ciencia, Innovación y Universidades of Spain, “Garantía Juvenil” scholarship from Comunidad de Madrid, and the financial support from Boosting Agricultural Insurance based on Earth Observation data - BEACON project under agreement Nº 821964, funded under H2020EU, DT-SPACE-01-EO-2018-2020.

ACS Style

Ernesto Sanz; Andrés Almeida-Ñauñay; Carlos G. Diaz Ambrona; Antonio Saa-Requejo; Margarita Ruiz-Ramos; Alfredo Rodríguez; Ana M. Tarquis. Spatial rangeland variability: using summary statistics and multifractal analysis to classify and monitor rangelands. 2021, 1 .

AMA Style

Ernesto Sanz, Andrés Almeida-Ñauñay, Carlos G. Diaz Ambrona, Antonio Saa-Requejo, Margarita Ruiz-Ramos, Alfredo Rodríguez, Ana M. Tarquis. Spatial rangeland variability: using summary statistics and multifractal analysis to classify and monitor rangelands. . 2021; ():1.

Chicago/Turabian Style

Ernesto Sanz; Andrés Almeida-Ñauñay; Carlos G. Diaz Ambrona; Antonio Saa-Requejo; Margarita Ruiz-Ramos; Alfredo Rodríguez; Ana M. Tarquis. 2021. "Spatial rangeland variability: using summary statistics and multifractal analysis to classify and monitor rangelands." , no. : 1.

Preprint content
Published: 08 April 2021
Reads 0
Downloads 0

Rangeland and agricultural landscapes are complex and multifractal based on the interaction of biotic and abiotic factors such as soil, meteorology, and vegetation. The effects of land-uses on these areas modify their characteristics and dynamics.  The use of Normalized Difference Vegetation Index (NDVI) and NDVI anomalies (NDVIa) from satellite time series can effectively aid on understanding the differences among rangeland uses and types.

Multifractal detrended fluctuation analysis (MDFA) focuses on measuring variations of the moments of the absolute difference of their values at different scales. This allows us to use different multifractal exponent such as generalized Hurst exponent (H(q)), and the scaling exponent (ζ(q)) to characterize each area.

We collected the time series using satellite data of MODIS (MOD09Q1.006) from 2002 to 2019. Two areas from southeastern Spain (Murcia province) of 6.25 Km2 were selected. Each area has 132 pixels with a spatial resolution of 250 x 250 m2 and a temporal resolution of 8 days. The areas were selected to compare two types of arid rangeland. Area 1 (A1) is mainly covered by a mixed herbaceous cropland and grassland, Area 2 (A2) presents tree crops as well as a small patch of Mediterranean scrubland.

MDFA was used on every pixel of each area and H(q), and ζ(q) were plotted and compared. Our results report different exponent behaviours for diverse rangeland type or use. Within each area when different vegetation types are present MFDFA can allow us to distinguish among them such as in A2 where the pixels composing the river that crosses the area show less antipersistent character than the surrounding tree crops.
Comparing the scaling exponent of NDVI and NDVIa also suggest a difference of influence on the multifractal character of long-range correlations. This influence is much stronger in A4 than the three others, having their multifractal character due more heavily to probability density function.

We conclude that MDFA is a good tool to characterize arid rangelands spatial heterogeneity, particularly for rangeland with different vegetation types. It can be used to monitor and manage arid rangeland. It can be useful for policy-makers for short- and long-term solutions.

Acknowledgements: The authors acknowledge the support of Project No. PGC2018-093854-B-I00 of the Ministerio de Ciencia Innovación y Universidades of Spain, “Garantía Juvenil” scholarship from Comunidad de Madrid, and the financial support from Boosting Agricultural Insurance based on Earth Observation data - BEACON project under agreement Nº 821964, funded under H2020EU, DT-SPACE-01-EO-2018-2020.

ACS Style

Ernesto Sanz Sancho; Antonio Saa-Requejo; Carlos G. Diaz-Ambrona; Margarita Ruiz-Ramos; Ana M. Tarquis. Multifractal analysis of spatial heterogeneity in Spanish arid rangelands. 2021, 1 .

AMA Style

Ernesto Sanz Sancho, Antonio Saa-Requejo, Carlos G. Diaz-Ambrona, Margarita Ruiz-Ramos, Ana M. Tarquis. Multifractal analysis of spatial heterogeneity in Spanish arid rangelands. . 2021; ():1.

Chicago/Turabian Style

Ernesto Sanz Sancho; Antonio Saa-Requejo; Carlos G. Diaz-Ambrona; Margarita Ruiz-Ramos; Ana M. Tarquis. 2021. "Multifractal analysis of spatial heterogeneity in Spanish arid rangelands." , no. : 1.

Journal article
Published: 24 February 2021 in Remote Sensing
Reads 0
Downloads 0

Rangeland degradation caused by increasing misuses remains a global concern. Rangelands have a remarkable spatiotemporal heterogeneity, making them suitable to be monitored with remote sensing. Among the remotely sensed vegetation indices, Normalized Difference Vegetation Index (NDVI) is most used in ecology and agriculture. In this paper, we research the relationship of NDVI with temperature, precipitation, and Aridity Index (AI) in four different arid rangeland areas in Spain’s southeast. We focus on the interphase variability, studying time series from 2002 to 2019 with regression analysis and lagged correlation at two different spatial resolutions (500 × 500 and 250 × 250 m2) to understand NDVI response to meteorological variables. Intraseasonal phases were defined based on NDVI patterns. Strong correlation with temperature was reported in phases with high precipitations. The correlation between NDVI and meteorological series showed a time lag effect depending on the area, phase, and variable observed. Differences were found between the two resolutions, showing a stronger relationship with the finer one. Land uses and management affected the NDVI dynamics heavily strongly linked to temperature and water availability. The relationship between AI and NDVI clustered the areas in two groups. The intraphases variability is a crucial aspect of NDVI dynamics, particularly in arid regions.

ACS Style

Ernesto Sanz; Antonio Saa-Requejo; Carlos Díaz-Ambrona; Margarita Ruiz-Ramos; Alfredo Rodríguez; Eva Iglesias; Paloma Esteve; Bárbara Soriano; Ana Tarquis. Normalized Difference Vegetation Index Temporal Responses to Temperature and Precipitation in Arid Rangelands. Remote Sensing 2021, 13, 840 .

AMA Style

Ernesto Sanz, Antonio Saa-Requejo, Carlos Díaz-Ambrona, Margarita Ruiz-Ramos, Alfredo Rodríguez, Eva Iglesias, Paloma Esteve, Bárbara Soriano, Ana Tarquis. Normalized Difference Vegetation Index Temporal Responses to Temperature and Precipitation in Arid Rangelands. Remote Sensing. 2021; 13 (5):840.

Chicago/Turabian Style

Ernesto Sanz; Antonio Saa-Requejo; Carlos Díaz-Ambrona; Margarita Ruiz-Ramos; Alfredo Rodríguez; Eva Iglesias; Paloma Esteve; Bárbara Soriano; Ana Tarquis. 2021. "Normalized Difference Vegetation Index Temporal Responses to Temperature and Precipitation in Arid Rangelands." Remote Sensing 13, no. 5: 840.

Journal article
Published: 15 December 2020 in Agronomy
Reads 0
Downloads 0

In the Amazon, the Yasuní Biosphere Reserve (YBR) is considered a natural and cultural diversity hotspot. It is populated by several indigenous groups, including the Kichwa, who are characterized by their traditional systems of production, which are a means of subsistence and socio-ecological integration. The objective of this research was to evaluate the sustainability of small farmers who use a traditional agroforestry system (chakra) within the buffer, transition, and core zones of the YBR. We conducted 133 interviews with Kichwa heads of households. The socio-demographic structure and distribution were identified, and the response-inducing sustainability evaluation (RISE) methodology was used to evaluate chakra sustainability according to social, economic, and ecological dimensions, expressed using 10 indicators from 50 parameters, valued from 0 (worst case) to 100 (best case). The results are expressed in a polygon, defined by the areas: (1) good performance, (2) medium performance, and (3) poor performance. We employed the multivariate classification hierarchical cluster technique and analysis of variance (ANOVA) to identify dissimilarities between groups of chakras and the existence of statistical differences, respectively. Among the studied indigenous Kichwas, a pyramidal structure progressive type was identified, which is characteristic of young populations and the nonexistence of significant differences between the RISE indicators and chakras. The lowest-scoring indicators using the RISE guidelines were: use of materials and environmental protection, animal production, economic viability and chakra administration. We provide suggestions for decision makers who support Kichwa populations in socio-productive management with sustainability goals. We to taking actions on the indicators identified with high priority to improve the sustainability in the chakras and sociodemographic dynamics.

ACS Style

Marco Heredia-R; Bolier Torres; Jhenny Cayambe; Nadia Ramos; Marcelo Luna; Carlos G. H. Diaz-Ambrona. Sustainability Assessment of Smallholder Agroforestry Indigenous Farming in the Amazon: A Case Study of Ecuadorian Kichwas. Agronomy 2020, 10, 1973 .

AMA Style

Marco Heredia-R, Bolier Torres, Jhenny Cayambe, Nadia Ramos, Marcelo Luna, Carlos G. H. Diaz-Ambrona. Sustainability Assessment of Smallholder Agroforestry Indigenous Farming in the Amazon: A Case Study of Ecuadorian Kichwas. Agronomy. 2020; 10 (12):1973.

Chicago/Turabian Style

Marco Heredia-R; Bolier Torres; Jhenny Cayambe; Nadia Ramos; Marcelo Luna; Carlos G. H. Diaz-Ambrona. 2020. "Sustainability Assessment of Smallholder Agroforestry Indigenous Farming in the Amazon: A Case Study of Ecuadorian Kichwas." Agronomy 10, no. 12: 1973.

Journal article
Published: 28 March 2020 in International Journal on Advanced Science, Engineering and Information Technology
Reads 0
Downloads 0

The Yasuni Biosphere Reserve (YBR) occupies a unique biogeographic position in the world, where the richness of the four taxa (amphibians, birds, mammals and vascular plants) reaches maximum diversity. However, threats to species conservation are latent: the opening of roads, illegal logging, the advance of the agricultural frontier, oil extraction and the trade of wild meat in the western sector of the reserve. This paper aims to evaluate the sustainability of natural resources in multicultural communities: 1) Waorani Indigenous and 2) Migrant settlers, settled in the Diversity and Life Strip (DLS) in the YBR. Three households were defined per community, selected from the snowball sampling method. Thus, three methodological processes were applied: 1) Sustainability of natural resources using the SAFA program (version 2.4.1), it has four dimensions Good Governance (GG), Environmental Integrity (EI), Economic Resilience (ER) and Social Welfare (SW); 2) Direct observation; and 3) Lacing algorithm with the GeoGebra program used for the calculation of areas of simple polygons. The results showed that the dimension of least sustainability was ER in indigenous households and in-migrant settler households it was ER and SW. The largest sustainability area of 25,12 u2 in the migrant settler household1, while in Waorani indigenous the worst sustainability area had a value of 18,69 u2. The programs allow to promote a better understanding of the dynamics of the sustainability of natural resources. The issues identified as limited in the communities are a priority to improve sustainability.

ACS Style

Marco Heredia; Bolier Torres; Reinaldo Aleman; Carlos Bravo; Carlos Hernández Díaz-Ambrona. SAFA and GeoGebra Allies to Evaluate Natural and Cultural Sustainability: Yasuni Biosphere Reserve. International Journal on Advanced Science, Engineering and Information Technology 2020, 10, 880 -887.

AMA Style

Marco Heredia, Bolier Torres, Reinaldo Aleman, Carlos Bravo, Carlos Hernández Díaz-Ambrona. SAFA and GeoGebra Allies to Evaluate Natural and Cultural Sustainability: Yasuni Biosphere Reserve. International Journal on Advanced Science, Engineering and Information Technology. 2020; 10 (2):880-887.

Chicago/Turabian Style

Marco Heredia; Bolier Torres; Reinaldo Aleman; Carlos Bravo; Carlos Hernández Díaz-Ambrona. 2020. "SAFA and GeoGebra Allies to Evaluate Natural and Cultural Sustainability: Yasuni Biosphere Reserve." International Journal on Advanced Science, Engineering and Information Technology 10, no. 2: 880-887.

Journal article
Published: 26 November 2019 in Agricultural and Forest Meteorology
Reads 0
Downloads 0

Robust projections of climate impact on crop growth and productivity by crop models are key to designing effective adaptations to cope with future climate risk. However, current crop models diverge strongly in their climate impact projections. Previous studies tried to compare or improve crop models regarding the impact of one single climate variable. However, this approach is insufficient, considering that crop growth and yield are affected by the interactive impacts of multiple climate change factors and multiple interrelated biophysical processes. Here, a new comprehensive analysis was conducted to look holistically at the reasons why crop models diverge substantially in climate impact projections and to investigate which biophysical processes and knowledge gaps are key factors affecting this uncertainty and should be given the highest priorities for improvement. First, eight barley models and eight climate projections for the 2050s were applied to investigate the uncertainty from crop model structure in climate impact projections for barley growth and yield at two sites: Jokioinen, Finland (Boreal) and Lleida, Spain (Mediterranean). Sensitivity analyses were then conducted on the responses of major crop processes to major climatic variables including temperature, precipitation, irradiation, and CO2, as well as their interactions, for each of the eight crop models. The results showed that the temperature and CO2 relationships in the models were the major sources of the large discrepancies among the models in climate impact projections. In particular, the impacts of increases in temperature and CO2 on leaf area development were identified as the major causes for the large uncertainty in simulating changes in evapotranspiration, above-ground biomass, and grain yield. Our findings highlight that advancements in understanding the basic processes and thresholds by which climate warming and CO2 increases will affect leaf area development, crop evapotranspiration, photosynthesis, and grain formation in contrasting environments are needed for modeling their impacts.

ACS Style

Fulu Tao; Taru Palosuo; Reimund P. Rötter; Carlos G.H. Diaz-Ambrona; M. Inés Mínguez; Mikhail A. Semenov; Kurt Christian Kersebaum; Davide Cammarano; Xenia Specka; Claas Nendel; Amit Kumar Srivastava; Frank Ewert; Gloria Padovan; Roberto Ferrise; Pierre Martre; Lucía Rodríguez; Margarita Ruiz-Ramos; Thomas Gaiser; Jukka G. Höhn; Tapio Salo; Camilla Dibari; Alan H. Schulman. Why do crop models diverge substantially in climate impact projections? A comprehensive analysis based on eight barley crop models. Agricultural and Forest Meteorology 2019, 281, 107851 .

AMA Style

Fulu Tao, Taru Palosuo, Reimund P. Rötter, Carlos G.H. Diaz-Ambrona, M. Inés Mínguez, Mikhail A. Semenov, Kurt Christian Kersebaum, Davide Cammarano, Xenia Specka, Claas Nendel, Amit Kumar Srivastava, Frank Ewert, Gloria Padovan, Roberto Ferrise, Pierre Martre, Lucía Rodríguez, Margarita Ruiz-Ramos, Thomas Gaiser, Jukka G. Höhn, Tapio Salo, Camilla Dibari, Alan H. Schulman. Why do crop models diverge substantially in climate impact projections? A comprehensive analysis based on eight barley crop models. Agricultural and Forest Meteorology. 2019; 281 ():107851.

Chicago/Turabian Style

Fulu Tao; Taru Palosuo; Reimund P. Rötter; Carlos G.H. Diaz-Ambrona; M. Inés Mínguez; Mikhail A. Semenov; Kurt Christian Kersebaum; Davide Cammarano; Xenia Specka; Claas Nendel; Amit Kumar Srivastava; Frank Ewert; Gloria Padovan; Roberto Ferrise; Pierre Martre; Lucía Rodríguez; Margarita Ruiz-Ramos; Thomas Gaiser; Jukka G. Höhn; Tapio Salo; Camilla Dibari; Alan H. Schulman. 2019. "Why do crop models diverge substantially in climate impact projections? A comprehensive analysis based on eight barley crop models." Agricultural and Forest Meteorology 281, no. : 107851.

Article
Published: 21 September 2018 in Agroecology and Sustainable Food Systems
Reads 0
Downloads 0

Food and Nutritional Security (FNS) is still an outstanding problem, and rural areas of Guatemala demonstrate this by an increase in the undernourished population from 1.4 million in 1991 to 2.5 million in 2014. Some FNS programs were developed in the past, and our research evaluates the following: (1) the critical points perceived by farmers related to the sustainability of their systems, (2) the performance of FNS program through a set of 7 indicators, and (3) how the FNS levels are related to sustainability indicators among hamlets. We used mixed methods (participatory rural appraisals and 64 semi-structured household surveys) across six hamlets. The most robust 15 indicators were selected through correlation analysis. Two series of five least squares regression models determined that the critical points had significant impacts on economic disparities but failed to explain malnutrition levels. Consequently, we compared two contrasting hamlets according to their energy and protein supply. The results showed that FNS is linked to sustainability as the more self-reliant and equitable community exhibited higher food security. However, FNS depends upon a complex array of self-sufficiency strategies that remain linked to individual household idiosyncrasies.

ACS Style

Esperanza Arnés; Marta Astier; Omar Marín González; Carlos G.H. Diaz-Ambrona. Participatory evaluation of food and nutritional security through sustainability indicators in a highland peasant system in Guatemala. Agroecology and Sustainable Food Systems 2018, 43, 482 -513.

AMA Style

Esperanza Arnés, Marta Astier, Omar Marín González, Carlos G.H. Diaz-Ambrona. Participatory evaluation of food and nutritional security through sustainability indicators in a highland peasant system in Guatemala. Agroecology and Sustainable Food Systems. 2018; 43 (5):482-513.

Chicago/Turabian Style

Esperanza Arnés; Marta Astier; Omar Marín González; Carlos G.H. Diaz-Ambrona. 2018. "Participatory evaluation of food and nutritional security through sustainability indicators in a highland peasant system in Guatemala." Agroecology and Sustainable Food Systems 43, no. 5: 482-513.

Journal article
Published: 24 August 2018 in Sustainability
Reads 0
Downloads 0

Farmer field schools (FFSs) emerged in response to the gap left by the worldwide decline in agricultural extension services. With time, this methodology has been adapted to specific rural contexts to solve problems related to the sustainability of peasant-farming systems. In this study we draw upon empirical data regarding the peasant-farming system in the Nicaraguan highlands to evaluate whether FFSs have helped communities improve the sustainability of their systems and the food security of their residents using socioeconomic, environmental, and food and nutrition security (FNS) indicators. In order to appreciate the long-term impact, we studied three communities where FFSs were implemented eight, five, and three years ago, respectively, and we included participants and nonparticipants from each community. We found that FFSs have a gradual impact, as there are significant differences between participants and nonparticipants, and it is the community that first implemented FFSs that scores highest. The impact of FFSs is broad and long lasting for indicators related to participation, access to basic services, and conservation of natural resources. Finally, this paper provides evidence that FFSs have the potential to empower farmers; however, more attention needs to be paid to critical indicators like production costs and the use of external inputs in order to scale up their potential in the future.

ACS Style

Esperanza Arnés; Carlos G. H. Díaz-Ambrona; Omar Marín-González; Marta Astier. Farmer Field Schools (FFSs): A Tool Empowering Sustainability and Food Security in Peasant Farming Systems in the Nicaraguan Highlands. Sustainability 2018, 10, 3020 .

AMA Style

Esperanza Arnés, Carlos G. H. Díaz-Ambrona, Omar Marín-González, Marta Astier. Farmer Field Schools (FFSs): A Tool Empowering Sustainability and Food Security in Peasant Farming Systems in the Nicaraguan Highlands. Sustainability. 2018; 10 (9):3020.

Chicago/Turabian Style

Esperanza Arnés; Carlos G. H. Díaz-Ambrona; Omar Marín-González; Marta Astier. 2018. "Farmer Field Schools (FFSs): A Tool Empowering Sustainability and Food Security in Peasant Farming Systems in the Nicaraguan Highlands." Sustainability 10, no. 9: 3020.

Journal article
Published: 01 July 2018 in Agricultural Systems
Reads 0
Downloads 0

Smallholder agricultural systems have an important role in world food production. Agricultural smallholders in highland areas of the Mesoamerican dry-corridor are central to improve farming systems. The key issue is that the subsistence smallholders are joint producer-consumers, with insufficient food production due to extreme environmental and weather conditions or incomes to supplement their own production from market sources. Modelling offers an approach for testing and improving knowledge about complex systems. The aim of this paper is to describe and assess a biophysical and socio-economic model of the smallholder agricultural systems based on maize-bean intercropping in highland areas of Central America. A Vensim® DSS system dynamics model was developed for assessing the impact of Smallholder endowments on food security and to identify critical points to achieve sustainable food security and poverty alleviation in Agricultural Systems in Highland Areas of Central America (SASHACA). The SASHACA model integrates scientific and practical knowledge of crop management, labour, soil water content, soil nitrogen, food consumption and economic components of the system. Model evaluation was conducted through a wide set of tests for assessment of dynamic models and statistical comparison of simulated versus observed data derived from surveys. The model simulates realistic outputs and presents logical behavioural representation. The maximum relative uncertainty of output variables ranged from 30% to 53% for univariate and multivariate sensitivity analyses respectively. The model proved to be adequate for assessing food security under scenarios in low data availability areas. The SASHACA model could be adapted to simulate a wide range of smallholder agricultural systems in highland areas of Central America, and potentially in other locations.

ACS Style

Omar Marín-González; David Parsons; Esperanza Arnes-Prieto; Carlos G.H. Díaz-Ambrona. Building and evaluation of a dynamic model for assessing impact of smallholder endowments on food security in agricultural systems in highland areas of central America (SASHACA). Agricultural Systems 2018, 164, 152 -164.

AMA Style

Omar Marín-González, David Parsons, Esperanza Arnes-Prieto, Carlos G.H. Díaz-Ambrona. Building and evaluation of a dynamic model for assessing impact of smallholder endowments on food security in agricultural systems in highland areas of central America (SASHACA). Agricultural Systems. 2018; 164 ():152-164.

Chicago/Turabian Style

Omar Marín-González; David Parsons; Esperanza Arnes-Prieto; Carlos G.H. Díaz-Ambrona. 2018. "Building and evaluation of a dynamic model for assessing impact of smallholder endowments on food security in agricultural systems in highland areas of central America (SASHACA)." Agricultural Systems 164, no. : 152-164.

Journal article
Published: 01 January 2017 in European Journal of Agronomy
Reads 0
Downloads 0
ACS Style

F Tao; Reimund Rötter; Taru Palosuo; Carlos G.H. Diaz-Ambrona; M Ines Minguez; Mikhail Semenov; Kurt Christian Kersebaum; Claas Nendel; Davide Cammarano; Holger Hoffmann; Frank Ewert; Anaelle Dambreville; Pierre Martre; Lucía Rodríguez; Margarita Ruiz-Ramos; Thomas Gaiser; Jukka G. Höhn; Tapio Salo; Roberto Ferrise; Marco Bindi; Alan H. Schulman. Designing future barley ideotypes using a crop model ensemble. European Journal of Agronomy 2017, 82, 144 -162.

AMA Style

F Tao, Reimund Rötter, Taru Palosuo, Carlos G.H. Diaz-Ambrona, M Ines Minguez, Mikhail Semenov, Kurt Christian Kersebaum, Claas Nendel, Davide Cammarano, Holger Hoffmann, Frank Ewert, Anaelle Dambreville, Pierre Martre, Lucía Rodríguez, Margarita Ruiz-Ramos, Thomas Gaiser, Jukka G. Höhn, Tapio Salo, Roberto Ferrise, Marco Bindi, Alan H. Schulman. Designing future barley ideotypes using a crop model ensemble. European Journal of Agronomy. 2017; 82 ():144-162.

Chicago/Turabian Style

F Tao; Reimund Rötter; Taru Palosuo; Carlos G.H. Diaz-Ambrona; M Ines Minguez; Mikhail Semenov; Kurt Christian Kersebaum; Claas Nendel; Davide Cammarano; Holger Hoffmann; Frank Ewert; Anaelle Dambreville; Pierre Martre; Lucía Rodríguez; Margarita Ruiz-Ramos; Thomas Gaiser; Jukka G. Höhn; Tapio Salo; Roberto Ferrise; Marco Bindi; Alan H. Schulman. 2017. "Designing future barley ideotypes using a crop model ensemble." European Journal of Agronomy 82, no. : 144-162.

Journal article
Published: 01 December 2016 in Revista de Gestão Ambiental e Sustentabilidade
Reads 0
Downloads 0

As secas estão entre os tipos mais comuns de desastres, gerando grandes impactos socioeconômicos no mundo, especialmente quando se considera o caráter silencioso que elas apresentam. Esses fenômenos são cada vez mais frequentes, intensos e duradouros, o que nos dá uma ideia do que pode acontecer com a acentuação das mudanças climáticas. Este artigo visa proporcionar uma visão geral das medidas e políticas que abordam prevenção e preparação para as secas, frente aos impactos das alterações climáticas, no Estado do Ceará, Brasil. Este estudo aborda questões de políticas públicas relacionadas à gestão do risco de secas, a fim de permitir uma maior compreensão das políticas e programas, experiências e perspectivas baseadas no processo de elaboração do Plano Integrado de Gestão de Risco de Desastres o Estado do Ceará, Brasil (PIGRD-CE), assim como no desenvolvimento do Sistema de Alerta Precoce – Monitor de Secas –, bem como aborda a coordenação política que levou à criação do Comitê das secas. Como resultado, nós entendemos essa estratégia, fundamentada em preparação para secas, como uma ferramenta capaz de aumentar a adaptabilidade e resiliência do processo político. Nesse sentido, apresenta-se a experiência acumulada pelo Estado do Ceará nos processos de gestão de secas com potencial promissor para replicabilidade em outros países latino-americanos também sujeitos a ameaças que as mudanças climáticas possam impor, em combinação com a análise de riscos relacionados – políticos/institucionais/culturais –, no desenvolvimento de políticas públicas para, assim, tecer as principais conclusões, lições aprendidas e recomendações.

ACS Style

Carlos Germano Ferreira Costa; Ana Karina Cavalcante Holanda; Carlos Gregorio Hernández Díaz-Ambrona. Riesgo, Innovación y Desarrollo en un Clima Cambiante: El Papel de las Políticas de Preparacíon para Sequías y Gestión de Riesgo de Desastres en Ceará, Brasil. Revista de Gestão Ambiental e Sustentabilidade 2016, 5, 87 -105.

AMA Style

Carlos Germano Ferreira Costa, Ana Karina Cavalcante Holanda, Carlos Gregorio Hernández Díaz-Ambrona. Riesgo, Innovación y Desarrollo en un Clima Cambiante: El Papel de las Políticas de Preparacíon para Sequías y Gestión de Riesgo de Desastres en Ceará, Brasil. Revista de Gestão Ambiental e Sustentabilidade. 2016; 5 (3):87-105.

Chicago/Turabian Style

Carlos Germano Ferreira Costa; Ana Karina Cavalcante Holanda; Carlos Gregorio Hernández Díaz-Ambrona. 2016. "Riesgo, Innovación y Desarrollo en un Clima Cambiante: El Papel de las Políticas de Preparacíon para Sequías y Gestión de Riesgo de Desastres en Ceará, Brasil." Revista de Gestão Ambiental e Sustentabilidade 5, no. 3: 87-105.

Journal article
Published: 01 November 2016 in Agricultural Systems
Reads 0
Downloads 0
ACS Style

Eva Iglesias; Karen Báez; Carlos H. Diaz-Ambrona. Assessing drought risk in Mediterranean Dehesa grazing lands. Agricultural Systems 2016, 149, 65 -74.

AMA Style

Eva Iglesias, Karen Báez, Carlos H. Diaz-Ambrona. Assessing drought risk in Mediterranean Dehesa grazing lands. Agricultural Systems. 2016; 149 ():65-74.

Chicago/Turabian Style

Eva Iglesias; Karen Báez; Carlos H. Diaz-Ambrona. 2016. "Assessing drought risk in Mediterranean Dehesa grazing lands." Agricultural Systems 149, no. : 65-74.

Journal article
Published: 01 January 2015 in Biological Conservation
Reads 0
Downloads 0
ACS Style

Ramón Perea; Ramón Perea García-Calvo; Carlos G.H. Diaz-Ambrona; Alfonso San Miguel. The reintroduction of a flagship ungulate Capra pyrenaica: Assessing sustainability by surveying woody vegetation. Biological Conservation 2015, 181, 9 -17.

AMA Style

Ramón Perea, Ramón Perea García-Calvo, Carlos G.H. Diaz-Ambrona, Alfonso San Miguel. The reintroduction of a flagship ungulate Capra pyrenaica: Assessing sustainability by surveying woody vegetation. Biological Conservation. 2015; 181 ():9-17.

Chicago/Turabian Style

Ramón Perea; Ramón Perea García-Calvo; Carlos G.H. Diaz-Ambrona; Alfonso San Miguel. 2015. "The reintroduction of a flagship ungulate Capra pyrenaica: Assessing sustainability by surveying woody vegetation." Biological Conservation 181, no. : 9-17.

Journal article
Published: 04 April 2014 in Current Sustainable/Renewable Energy Reports
Reads 0
Downloads 0

Ensuring that the food supply both keeps up with current population growth and changing food preferences are the main challenges of agriculture. Food security includes access to a sufficient amount of quality food products. Population growth, food preferences and economic wealth are variables that drive agricultural production, although agriculture does produce raw materials other than for food. The world population of 9 billion projected for 2050 will require food production to increase by 50 % to 70 %, with raw materials and waste increasing by the same percentages. However, there will be no significant changes in the amount of arable land; the increase in production will come about through agricultural intensification, the disparity between real and potential yield being known as the yield gap. Innovation in management techniques will focus on optimizing water use, both for irrigated and rain-fed crops. In addition, nutrient management will have to be intensified to fill the production gap. Sustainable management focuses on improving nutrient efficiency, but also includes waste management. Sustainable agriculture must introduce a circular economy model and reverse logistics for waste management, and in particular to the nutrient cycle.

ACS Style

Carlos G. H. Diaz-Ambrona; Emiliano Maletta. Achieving Global Food Security through Sustainable Development of Agriculture and Food Systems with Regard to Nutrients, Soil, Land, and Waste Management. Current Sustainable/Renewable Energy Reports 2014, 1, 57 -65.

AMA Style

Carlos G. H. Diaz-Ambrona, Emiliano Maletta. Achieving Global Food Security through Sustainable Development of Agriculture and Food Systems with Regard to Nutrients, Soil, Land, and Waste Management. Current Sustainable/Renewable Energy Reports. 2014; 1 (2):57-65.

Chicago/Turabian Style

Carlos G. H. Diaz-Ambrona; Emiliano Maletta. 2014. "Achieving Global Food Security through Sustainable Development of Agriculture and Food Systems with Regard to Nutrients, Soil, Land, and Waste Management." Current Sustainable/Renewable Energy Reports 1, no. 2: 57-65.

Journal article
Published: 08 May 2013 in Revista iberoamericana de estudios de desarrollo = Iberoamerican journal of development studies
Reads 0
Downloads 0

The rotation maize and dry bean provides the main food supply of smallholder farmers in Honduras. Crop model assessment of climate change impacts (2070-2099 compared to a 1961-1990 baseline) on a maize-dry ben rotation for several sites across a range of climatic zones and elevations in Honduras. Low productivity systems, together with an uncertain future climate, pose a high level of risk for food security. The cropping systems simulation dynamic model CropSyst was calibrated and validated upon field trail site at Zamorano, then run with baseline and future climate scenarios based upon general circulation models (GCM) and the ClimGen synthetic daily weather generator. Results indicate large uncertainty in crop production from various GCM simulations and future emissions scenarios, but generally reduced yields at low elevations by 0% to 22% in suitable areas for crop production and increased yield at the cooler, on the hillsides, where farming needs to reduce soil erosion with conservation techniques. Further studies are needed to investigate strategies to reduce impacts and to explore adaptation tactics. CITE AS: Diaz-Ambrona, C., Gigena, R., Mendoza, C. (2013). Climate change impacts on maize and dry bean yields of smallholder farmers in Honduras. Iberoamerican Journal of Development Studies, 2 (1): 4-22

ACS Style

Carlos G.H. Diaz-Ambrona; Ruben Gigena; Carlos Onan Mendoza. Climate change impacts on maize and dry bean yields of smallholder farmers in Honduras. Revista iberoamericana de estudios de desarrollo = Iberoamerican journal of development studies 2013, 2, 4-22 .

AMA Style

Carlos G.H. Diaz-Ambrona, Ruben Gigena, Carlos Onan Mendoza. Climate change impacts on maize and dry bean yields of smallholder farmers in Honduras. Revista iberoamericana de estudios de desarrollo = Iberoamerican journal of development studies. 2013; 2 (1):4-22.

Chicago/Turabian Style

Carlos G.H. Diaz-Ambrona; Ruben Gigena; Carlos Onan Mendoza. 2013. "Climate change impacts on maize and dry bean yields of smallholder farmers in Honduras." Revista iberoamericana de estudios de desarrollo = Iberoamerican journal of development studies 2, no. 1: 4-22.

Journal article
Published: 01 December 2008 in Acta Horticulturae
Reads 0
Downloads 0
ACS Style

C.G.H. Díaz-Ambrona; C. González De Miguel; J. Martínez-Valderrama. THREE LAYER COFFEE PLANTATION MODEL. Acta Horticulturae 2008, 319 -324.

AMA Style

C.G.H. Díaz-Ambrona, C. González De Miguel, J. Martínez-Valderrama. THREE LAYER COFFEE PLANTATION MODEL. Acta Horticulturae. 2008; (802):319-324.

Chicago/Turabian Style

C.G.H. Díaz-Ambrona; C. González De Miguel; J. Martínez-Valderrama. 2008. "THREE LAYER COFFEE PLANTATION MODEL." Acta Horticulturae , no. 802: 319-324.

Journal article
Published: 01 December 2008 in Acta Horticulturae
Reads 0
Downloads 0
ACS Style

F.C. Da Silva; C.G.H. Díaz-Ambrona; M.S. Buckeridge; A. Souza; V. Barbieri; Durval Dourado Neto. SUGARCANE AND CLIMATE CHANGE: EFFECTS OF CO2 ON POTENTIAL GROWTH AND DEVELOPMENT. Acta Horticulturae 2008, 331 -336.

AMA Style

F.C. Da Silva, C.G.H. Díaz-Ambrona, M.S. Buckeridge, A. Souza, V. Barbieri, Durval Dourado Neto. SUGARCANE AND CLIMATE CHANGE: EFFECTS OF CO2 ON POTENTIAL GROWTH AND DEVELOPMENT. Acta Horticulturae. 2008; (802):331-336.

Chicago/Turabian Style

F.C. Da Silva; C.G.H. Díaz-Ambrona; M.S. Buckeridge; A. Souza; V. Barbieri; Durval Dourado Neto. 2008. "SUGARCANE AND CLIMATE CHANGE: EFFECTS OF CO2 ON POTENTIAL GROWTH AND DEVELOPMENT." Acta Horticulturae , no. 802: 331-336.

Journal article
Published: 20 March 2007 in Climatic Change
Reads 0
Downloads 0

The first-order or initial agricultural impacts of climate change in the Iberian Peninsula were evaluated by linking crop simulation models to several high-resolution climate models (RCMs). The RCMs provided the daily weather data for control, and the A2 and B2 IPCC scenarios. All RCMs used boundary conditions from the atmospheric general circulation model (AGCM) HadAM3 while two were also bounded to two other AGCMs. The analyses were standardised to control the sources of variation and uncertainties that were added in the process. Climatic impacts on wheat and maize of climate were derived from the A2 scenario generated by RCMs bounded to HadAM3. Some results derived from B2 scenarios are included for comparisons together with impacts derived from RCMs using different boundary conditions. Crop models were used as impact models and yield was used as an indicator that summarised the effects of climate to quantify initial impacts and differentiate among regions. Comparison among RCMs was made through the choice of different crop management options. All RCM-crop model combinations detected crop failures for winter wheat in the South under control and future scenarios, and projected yield increases for spring wheat in northern and high altitude areas. Although projected impacts differed among RCMs, similar trends emerged for relative yields for some regions. RCM-crop model outputs compared favourably to others using European Re-Analysis data (ERA-15), establishing the feasibility of using direct daily outputs from RCM for impact analysis. Uncertainties were quantified as the standard deviation of the mean obtained for all RCMs in each location and differed greatly between winter (wheat) and summer (maize) seasons, being smaller in the latter.

ACS Style

María Inés Mínguez; Margarita Ruiz-Ramos; Carlos G.H. Diaz-Ambrona; Miguel Quemada; Federico Sau. First-order impacts on winter and summer crops assessed with various high-resolution climate models in the Iberian Peninsula. Climatic Change 2007, 81, 343 -355.

AMA Style

María Inés Mínguez, Margarita Ruiz-Ramos, Carlos G.H. Diaz-Ambrona, Miguel Quemada, Federico Sau. First-order impacts on winter and summer crops assessed with various high-resolution climate models in the Iberian Peninsula. Climatic Change. 2007; 81 (S1):343-355.

Chicago/Turabian Style

María Inés Mínguez; Margarita Ruiz-Ramos; Carlos G.H. Diaz-Ambrona; Miguel Quemada; Federico Sau. 2007. "First-order impacts on winter and summer crops assessed with various high-resolution climate models in the Iberian Peninsula." Climatic Change 81, no. S1: 343-355.

Journal article
Published: 17 March 2007 in Climatic Change
Reads 0
Downloads 0

The uncertainties and sources of variation in projected impacts of climate change on agriculture and terrestrial ecosystems depend not only on the emission scenarios and climate models used for projecting future climates, but also on the impact models used, and the local soil and climatic conditions of the managed or unmanaged ecosystems under study. We addressed these uncertainties by applying different impact models at site, regional and continental scales, and by separating the variation in simulated relative changes in ecosystem performance into the different sources of uncertainty and variation using analyses of variance. The crop and ecosystem models used output from a range of global and regional climate models (GCMs and RCMs) projecting climate change over Europe between 1961-1990 and 2071-2 100 under the IPCC SIZES scenarios. The projected impacts on productivity of crops and ecosystems included the direct effects of increased CO2 concentration on photosynthesis. The variation in simulated results attributed to differences between the climate models were, in all cases, smaller than the variation attributed to either emission scenarios or local conditions. The methods used for applying the climate model outputs played a larger role than the choice of the GCM or RCM. The thermal suitability for grain maize cultivation in Europe was estimated to expand by 30-50% across all SRES emissions scenarios. Strong increases in net primary productivity (NPP) (35-54%) were projected in Dorthem European ecosystems as a result of a longer growing season and higher CO2 concentrations. Changing water balance dominated the projected responses of southern European ecosystems, with NPP declining or increasing only slightly relative to preserit-day conditions. Both site and continental scale models showed large increases in yield of rain-fed winter wheat for northern Europe, with smaller increases or even decreases in southern Europe. Site-based, regional and continental scale models showed large spatial variations in the response of nitrate leaching from winter wheat cultivation to projected climate change due to strong interactions with soils and climate. The variation in simulated impacts was smaller between scenarios based on RCMs nested within the same GCM than between scenarios based on different GCMs or between emission scenarios

ACS Style

Jørgen E. Olesen; T. R. Carter; Carlos G.H. Diaz-Ambrona; Stefan Fronzek; T. Heidmann; Thomas Hickler; T. Holt; M Ines Minguez; P. Morales; J. P. Palutikof; Miguel Quemada; M. Ruiz-Ramos; Gitte Holton Rubæk; F. Sau; Benjamin Smith; Martin Sykes. Uncertainties in projected impacts of climate change on European agriculture and terrestrial ecosystems based on scenarios from regional climate models. Climatic Change 2007, 81, 123 -143.

AMA Style

Jørgen E. Olesen, T. R. Carter, Carlos G.H. Diaz-Ambrona, Stefan Fronzek, T. Heidmann, Thomas Hickler, T. Holt, M Ines Minguez, P. Morales, J. P. Palutikof, Miguel Quemada, M. Ruiz-Ramos, Gitte Holton Rubæk, F. Sau, Benjamin Smith, Martin Sykes. Uncertainties in projected impacts of climate change on European agriculture and terrestrial ecosystems based on scenarios from regional climate models. Climatic Change. 2007; 81 (1):123-143.

Chicago/Turabian Style

Jørgen E. Olesen; T. R. Carter; Carlos G.H. Diaz-Ambrona; Stefan Fronzek; T. Heidmann; Thomas Hickler; T. Holt; M Ines Minguez; P. Morales; J. P. Palutikof; Miguel Quemada; M. Ruiz-Ramos; Gitte Holton Rubæk; F. Sau; Benjamin Smith; Martin Sykes. 2007. "Uncertainties in projected impacts of climate change on European agriculture and terrestrial ecosystems based on scenarios from regional climate models." Climatic Change 81, no. 1: 123-143.