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1.
Agron Sustain Dev ; 43(6): 75, 2023.
Article En | MEDLINE | ID: mdl-37969112

Early energy analyses of agriculture revealed that behind higher labor and land productivity of industrial farming, there was a decrease in energy returns on energy (EROI) invested, in comparison to more traditional organic agricultural systems. Studies on recent trends show that efficiency gains in production and use of inputs have again somewhat improved energy returns. However, most of these agricultural energy studies have focused only on external inputs at the crop level, concealing the important role of internal biomass flows that livestock and forestry recirculate within agroecosystems. Here, we synthesize the results of 82 farm systems in North America and Europe from 1830 to 2012 that for the first time show the changing energy profiles of agroecosystems, including livestock and forestry, with a multi-EROI approach that accounts for the energy returns on external inputs, on internal biomass reuses, and on all inputs invested. With this historical circular bioeconomic approach, we found a general trend towards much lower external returns, little or no increases in internal returns, and almost no improvement in total returns. This "energy trap" was driven by shifts towards a growing dependence of crop production on fossil-fueled external inputs, much more intensive livestock production based on feed grains, less forestry, and a structural disintegration of agroecosystem components by increasingly linear industrial farm managements. We conclude that overcoming the energy trap requires nature-based solutions to reduce current dependence on fossil-fueled external industrial inputs and increase the circularity and complexity of agroecosystems to provide healthier diets with less animal products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-023-00925-5.

2.
J Environ Radioact ; 208-209: 105981, 2019 Nov.
Article En | MEDLINE | ID: mdl-31212250

Some new results were obtained by the array of EN-detectors (Electron and Neutron detectors) developed in the frame of the PRISMA (PRImary Spectrum Measurement Array) project for Extensive Air Showers detection. Our EN-detectors running both on the Earth surface and underground are continuously measuring the environmental thermal neutron flux. Neutrons are partially produced by radioactive gas radon and its daughter decays through (α,n)-reactions in soil close to the detectors. Then neutrons thermalize in media and, being in equilibrium with it, they are sensitive to many geo-dynamic phenomena including earthquakes. In this work the EN-detectors were measuring the variations of an environmental neutron flux in Tibet (30.11 N, 90.53 E, 4300 m a.s.l) at a distance of ∼600 km from the collision zone of the Asian-Indian plates subduction zone (Nepal region). We have observed some anomalies in the dynamics of the neutron flux around the time of the catastrophic earthquakes of magnitude M = 7.8 happened in Gorkha (Nepal) on 25.04.2015 followed by a series of aftershocks of M > 6. The use of nuclear physics methods can provide novel results in geophysics and this work demonstrates the sensitivity of the environmental thermal neutron flux to changes in tense-deformed crust conditions caused by earthquakes with epicentral distances greater than 500 km.


Earthquakes , Neutrons , Radiation Monitoring/methods , Electrons , Gases , Radon/analysis , Soil , Tibet
3.
Sci Total Environ ; 674: 603-614, 2019 Jul 15.
Article En | MEDLINE | ID: mdl-31026792

The aim of this paper is to test two methodologies, applicable to different spatial scales (from regional to local), to predict the capacity of agroecosystems to provide habitats for the species richness of butterflies and birds, based on the ways their socio-metabolic flows change the ecological functionality of bio-cultural landscapes. First, we use the more general Intermediate Disturbance-Complexity (IDC) model to assess how different levels of human appropriation of photosynthetic production affect the landscape functional structure that hosts biodiversity. Second, we apply a more detailed Energy-Landscape Integrated Analysis (ELIA) model that focusses on the energy storage carried out by the internal biomass loops, and the energy information held in the network of energy flows driven by farmers, in order to correlate both (the energy reinvested and redistributed) with the energy imprinted in the landscape patterns and processes that sustain biodiversity. The results obtained after applying both models in the province and the metropolitan region of Barcelona support the Margalef's energy-information-structure hypothesis by showing positive relations between butterflies' species richness, IDC and ELIA, and between birds' species richness and energy information. Our findings support the view that strong relationships between farming energy flows, agroecosystem functioning and biodiversity can be detected, and highlight the importance of farmers' knowledge and labour to maintain bio-cultural landscapes.


Conservation of Natural Resources/methods , Environmental Monitoring , Agriculture , Animals , Biodiversity , Birds , Butterflies , Ecosystem , Farms , Humans
4.
Sci Total Environ ; 619-620: 1272-1285, 2018 Apr 01.
Article En | MEDLINE | ID: mdl-29734605

The debate about the relative merits of the 'land-sparing' and 'land-sharing' approaches to biodiversity conservation is usually addressed at local scale. Here, however, we undertake a regional-scale approach to this issue by exploring the association between the Human Appropriation of Net Primary Production (HANPP) and biodiversity components (plants, amphibians, reptiles, birds and mammals) across a gradient of human-transformed landscapes in Catalonia, Spain. We propose an Intermediate Disturbance Complexity (IDC) model to assess how human disturbance of the photosynthetic capacity affects the landscape patterns and processes that host biodiversity. This model enables us to explore the association between social metabolism (HANPP), landscape structure (composition and spatial configuration) and biodiversity (species richness) by using Negative Binomial Regression (NBR), Exploratory Factor Analysis (EFA) and Structural Equation Modelling (SEM). The empirical association between IDC and landscape complexity and HANPP in Catalonia confirms the expected values of the intermediate disturbance hypothesis. There is some increase in biodiversity when high IDC values correspond to landscape mosaics. NBR and EFA show positive associations between species richness and increasing values of IDC and forest cover for all biodiversity groups except birds. SEM shows that total biodiversity is positively determined by forest cover and, to a lesser extent, by HANPP, and that both factors are negatively associated with each other. The results suggest that 'natural' landscapes (i.e. those dominated by forests) and agroforestry mosaics (i.e. heterogeneous landscapes characterized by a set of land uses possessing contrasting disturbances) provide a synergetic contribution to biodiversity conservation. This 'virtuous triangle' consisting of forest cover, HANPP and biodiversity illustrates the complex human-nature relationships that exist across landscape gradients of human transformation. This energy-landscape integrated analysis provides a robust assessment of the ecological impact of land-use policies at regional scale.


Biodiversity , Environmental Monitoring/methods , Animals , Conservation of Natural Resources/methods
5.
Reg Environ Change ; 18(4): 1089-1101, 2018.
Article En | MEDLINE | ID: mdl-31258413

Energy efficiency in biomass production is a major challenge for a future transition to sustainable food and energy provision. This study uses methodologically consistent data on agroecosystem energy flows and different metrics of energetic efficiency from seven regional case studies in North America (USA and Canada) and Europe (Spain and Austria) to investigate energy transitions in Western agroecosystems from the late nineteenth to the late twentieth centuries. We quantify indicators such as external final energy return on investment (EFEROI, i.e., final produce per unit of external energy input), internal final EROI (IFEROI, final produce per unit of biomass reused locally), and final EROI (FEROI, final produce per unit of total inputs consumed). The transition is characterized by increasing final produce accompanied by increasing external energy inputs and stable local biomass reused. External inputs did not replace internal biomass reinvestments, but added to them. The results were declining EFEROI, stable or increasing IFEROI, and diverging trends in FEROI. The factors shaping agroecosystem energy profiles changed in the course of the transition: Under advanced organic and frontier agriculture of the late nineteenth and early twentieth centuries, population density and biogeographic conditions explained both agroecosystem productivity and energy inputs. In industrialized agroecosystems, biogeographic conditions and specific socio-economic factors influenced trends towards increased agroecosystem specialization. The share of livestock products in a region's final produce was the most important factor determining energy returns on investment.

6.
Ecol Econ ; 137: 220-230, 2017 07.
Article En | MEDLINE | ID: mdl-28674463

Degrowth has evolved within a decade from an activist movement into a multi-disciplinary academic paradigm. However, an overview taking stock of the peer-refereed degrowth literature is yet missing. Here, we review 91 articles that were published between 2006 and 2015. We find that the academic degrowth discourse occupies a small but expanding niche at the intersection of social and applied environmental sciences. The discourse is shaped by authors from high-income, mainly Mediterranean, countries. Until 2012, articles largely constitute conceptual essays endorsed by normative claims. More recently, degrowth has branched out into modelling, empirical assessments, and the study of concrete implementations. Authors tend to agree in that economic growth cannot be sustained ad infinitum on a resource constraint planet and that degrowth requires far reaching societal change. Whether degrowth should be considered as a collectively consented choice or an environmentally-imposed inevitability constitutes a major debate among degrowth thinkers. We argue that the academic discourse could benefit from rigid hypotheses testing through input-output modelling, material flow analysis, life-cycle assessments, or social surveys. By analyzing the potentials for non-market value creation and identifying concrete well-being benefits, the degrowth discourse could receive wider public support and contribute to a paradigmatic change in the social sciences.

7.
Dev Med Child Neurol ; 50(12): 953-5, 2008 Dec.
Article En | MEDLINE | ID: mdl-19046189

Microduplication of the 22q11.2 chromosomal region has been recognized since 1999 and has been associated with a highly variable phenotype. Neurodevelopmental impairment and behavioural problems are very common in patients with 22q11.2 duplication. Autism spectrum disorders (ASDs) have previously been reported in only two patients with 22q11.2 duplication and striking dysmorphic features. We report here on a 4-year-old male of healthy consanguineous parents presenting with ASD according to DSMIV, revised, criteria as a primary manifestation. The child walked at 16 months and started to say one word and some sounds. Parents noticed a subsequent developmental arrest. At 4 years his functional development age, evaluated by the Psychoeducational Profile, was roughly 6 months. Mild non-specific facial dysmorphism was noted. Genetic analyses of the child demonstrated a de novo microduplication of the 22q11.2 chromosomal region. This genetic anomaly was best seen in interphases of blood lymphocytes and in buccal smear nuclei. Our case illustrates once again the clinical heterogeneity of the 22q11.2 duplication as well as the wide genetic complexity of ASD. We suggest that genetic evaluation of ASD should include fluorescence in-situ hybridization analysis of the 22q11.2 chromosomal region.


Autistic Disorder/genetics , Cell Cycle Proteins/genetics , Chromosomes, Human, Pair 22/genetics , Gene Duplication , Transcription Factors/genetics , Autistic Disorder/diagnosis , Child, Preschool , Consanguinity , Developmental Disabilities/diagnosis , Developmental Disabilities/genetics , DiGeorge Syndrome/diagnosis , DiGeorge Syndrome/genetics , Diagnosis, Differential , Genetic Heterogeneity , Histone Chaperones , Humans , In Situ Hybridization, Fluorescence , Male , Phenotype
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