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11.
Llorenç Milà i Canals Christian Bauer Jochen Depestele Alain Dubreuil Ruth Freiermuth Knuchel Gérard Gaillard Ottar Michelsen Ruedi Müller-Wenk Bernt Rydgren 《The International Journal of Life Cycle Assessment》2007,12(1):5-15
Background, Aim and Scope
Land use by agriculture, forestry, mining, house-building or industry leads to substantial impacts, particularly on biodiversity
and on soil quality as a supplier of life support functions. Unfortunately there is no widely accepted assessment method so
far for land use impacts. This paper presents an attempt, within the UNEP-SETAC Life Cycle Initiative, to provide a framework
for the Life Cycle Impact Assessment (LCIA) of land use.
Materials and Methods:
This framework builds from previous documents, particularly the SETAC book on LCIA (Lindeijer et al. 2002), developing essential
issues such as the reference for occupation impacts; the impact pathways to be included in the analysis; the units of measure
in the impact mechanism (land use interventions to impacts); the ways to deal with impacts in the future; and bio-geographical
differentiation.
Results:
The paper describes the selected impact pathways, linking the land use elementary flows (occupation; transformation) and parameters
(intensity) registered in the inventory (LCI) to the midpoint impact indicators and to the relevant damage categories (natural
environment and natural resources). An impact occurs when the land properties are modified (transformation) and also when
the current man-made properties are maintained (occupation).
Discussion:
The size of impact is the difference between the effect on land quality from the studied case of land use and a suitable reference
land use on the same area (dynamic reference situation). The impact depends not only on the type of land use (including coverage
and intensity) but is also heavily influenced by the bio-geographical conditions of the area. The time lag between the land
use intervention and the impact may be large; thus land use impacts should be calculated over a reasonable time period after
the actual land use finishes, at least until a new steady state in land quality is reached.
Conclusions:
Guidance is provided on the definition of the dynamic reference situation and on methods and time frame to assess the impacts
occurring after the actual land use. Including the occupation impacts acknowledges that humans are not the sole users of land.
Recommendations and Perspectives:
The main damages affected by land use that should be considered by any method to assess land use impacts in LCIA are: biodiversity
(existence value); biotic production potential (including soil fertility and use value of biodiversity); ecological soil quality
(including life support functions of soil other than biotic production potential). Bio-geographical differentiation is required
for land use impacts, because the same intervention may have different consequences depending on the sensitivity and inherent
land quality of the environment where it occurs. For the moment, an indication of how such task could be done and likely bio-geographical
parameters to be considered are suggested. The recommendation of indicators for the suggested impact categories is a matter
of future research. 相似文献
12.
Vicenç Méndez Daniel Campos Isaac Llopis Werner Horsthemke 《Bulletin of mathematical biology》2010,72(2):432-443
Population dynamics in spatially extended systems can be modeled by Coupled Map Lattices (CML). We employ such equations to
study the behavior of populations confined to a finite patch surrounded by a completely hostile environment. By means of the
Galerkin projection and the normal solution ansatz, we are able to find analytical expressions for the critical patch size
and show the existence of chaotic patterns. The analytical solutions provided are shown to fit, under the appropriate approximations,
the dynamics of a logistic map. This interesting result, together with our discussion, suggests the existence of a universal
class of spatially extended systems directly linked to the well-known characteristics of the logistic map. 相似文献
13.
Gabriel Blanca Miguel Cueto Julián Fuentes Llorenç Sáez Rubén Tarifa 《Nordic Journal of Botany》2018,36(8)
Linaria qartobensis, from southern Iberian Peninsula, is here newly described, illustrated and compared with its morphologically closest relatives from L. sect. Supinae: L. ricardoi and L. orbensis. The new species is characterized by longer calyx lobes, corolla and spur, violet corolla with yellow‐orangish palate, big and globose capsule, and seeds with black and prominently white‐tuberculate disc and subentire wing. Linaria qartobensis is an endemic species growing on marly deposits from the Guadalquivir river basin, in the Córdoba province (Andalusia, Spain). 相似文献
14.
Phenomics allows identification of genomic regions affecting maize stomatal conductance with conditional effects of water deficit and evaporative demand
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Santiago Alvarez Prado Llorenç Cabrera‐Bosquet Antonin Grau Aude Coupel‐Ledru Emilie J. Millet Claude Welcker François Tardieu 《Plant, cell & environment》2018,41(2):314-326
Stomatal conductance is central for the trades‐off between hydraulics and photosynthesis. We aimed at deciphering its genetic control and that of its responses to evaporative demand and water deficit, a nearly impossible task with gas exchanges measurements. Whole‐plant stomatal conductance was estimated via inversion of the Penman–Monteith equation from data of transpiration and plant architecture collected in a phenotyping platform. We have analysed jointly 4 experiments with contrasting environmental conditions imposed to a panel of 254 maize hybrids. Estimated whole‐plant stomatal conductance closely correlated with gas‐exchange measurements and biomass accumulation rate. Sixteen robust quantitative trait loci (QTLs) were identified by genome wide association studies and co‐located with QTLs of transpiration and biomass. Light, vapour pressure deficit, or soil water potential largely accounted for the differences in allelic effects between experiments, thereby providing strong hypotheses for mechanisms of stomatal control and a way to select relevant candidate genes among the 1–19 genes harboured by QTLs. The combination of allelic effects, as affected by environmental conditions, accounted for the variability of stomatal conductance across a range of hybrids and environmental conditions. This approach may therefore contribute to genetic analysis and prediction of stomatal control in diverse environments. 相似文献
15.
Llorenç Sabate Rafael Franco Enric I. Canela Josep J. Centelles Marta Cascante 《Molecular and cellular biochemistry》1995,142(1):9-17
A mathematical model based on kinetic data taken from the literature is presented for the pentose phosphate pathway in fasted rat liver steady-state. Since the oxidative and non oxidative pentose phosphate pathway can act independently, the complete (oxidative + non oxidative) and the non oxidative pentose pathway were simulated.Sensitivity analyses are reported which show that the fluxes are mainly regulated by D-glucose-6-phosphate dehydrogenase (for the oxidative pathway) and by transketolase (for the non oxidative pathway). The most influent metabolites were the group ATP, ADP, P1 and the group NADPH, NADP+ (for the non oxidative pathway).Abbreviations GK
Glucokinase, (E.C. 2.7.1.2.)
- G6PDH
D-glucose-6-phosphate dehydrogenase, (E.C. 1.1.1.49)
- PLase
6-Phosphogluconelactonase, (E.C. 3.1.1.31.)
- PGIcDH
6-Phosphogluconate dehydrogenase, (E.C. 1.1.1.44)
- RPI
D-ribose-5-phosphate keto-isomerase, (E.C. 5.3.1.6)
- TK
D-sedoheptulose-7-phosphate: D-glyceraldehyde-3-phosphate glycol-aldehyde transferase, (E.C. 2.2.1.1.)
- TA
D-sedoheptulose-7-phosphate: D-glyceraldehyde-3-phosphate dihydroxyacetone transferase, (E.C. 2.2.1.2)
- EP
D-ribulose-5-phosphate-3-epimerase, (E.C. 5.1.3.1)
- PGI
D-glucose-6-phosphate keto-isomerase, (E.C. 5.3.1.9)
- TPI
D-glyceraldehyde-3-phosphate keto-isomerase, (E.C.5.3.1.1) 相似文献
16.
Thomas Nemecek Niels Jungbluth Llorenç Milà i Canals Rita Schenck 《The International Journal of Life Cycle Assessment》2016,21(5):607-620
Purpose
This article introduces the special issue “LCA of nutrition and food consumption” and 14 papers selected from the Ninth LCA Food Conference in San Francisco in October 2014.Literature overview
The scientific literature in the field of food LCA has increased more than ten times during the last 15 years. Nutrition has a high contribution to the total environmental impacts of consumption. Agricultural production often dominates the impacts, but its importance depends on the type of product, its production mode, transport, and processing. Local or domestic products reduce transports, but this advantage can be lost if the impacts of the raw material production are substantially increased. Diets containing less meat tend to be more environmentally friendly. Several studies concluded that respecting the dietary recommendations for a healthy diet would reduce the overall environmental impacts in the developed countries, although this is not a universal conclusion.Contribution of this special issue
Eight papers analyze the environmental impacts of catering and in-house food consumption and impacts on sectoral and national levels; four papers presents tools and methods to better assess the impacts of nutrition and to implement the results in practical decision-making. Finally, two contributions analyze the impacts of food waste and reduction options.Challenges for the environmental assessment of nutrition
(i) Comprehensive assessment. Most studies only analyze climate impacts, although data, methods, and tools are readily available for a more comprehensive analysis. (ii) Assessment of sustainability. The social dimension remains the weakest pillar. (iii) Data availability is still an obstacle, but significant progress has been made in recent years. (iv) Lack of harmonization of methodologies makes comparisons among studies difficult. (v) Land use. Enhanced consideration of land use impacts on biodiversity and ecosystem services is required in LCA. (vi) Defining the functional unit including nutritional aspects, food security, and health needs further work. (vii) Consumer behavior. Its impacts are still little assessed. (viii) Communication of the environmental impact assessment results to stakeholders including policy-makers and consumers needs additional efforts.Research needs and outlook
(i) Development of holistic approaches for the assessment of sustainable food systems, (ii) assessment of land use related impacts and inclusion of ecosystem services, (iii) exploration of LCA results for policy support and decision-making, (iv) investigation of food consumption patterns in developing and emerging countries, and (v) harmonization of databases.17.
18.
Almudena Hospido Llorenç Milà i Canals Sarah McLaren Monica Truninger Gareth Edwards-Jones Roland Clift 《The International Journal of Life Cycle Assessment》2009,14(5):381-391
Background, aim and scope Considerable debate surrounds the assessment of the environmental impacts and the ethical justification for providing a year-round
supply of fresh produce to consumers in the developed countries of northern Europe. Society is seeking environmentally sustainable
supply chains which maintain the variety of fresh food on offer throughout the year. This paper compares the environmental
impacts of different supply chains providing lettuce all year round to the UK and considers consumers' meanings of—and attitudes
to—available options. Lettuce has been selected as a case study as its consumption has grown steadily during the last two
decades and the supply chains through cold months are protected cropping in the UK and field cropping in Spain; during warm
months, lettuce is sourced from field cropping in the UK.
Materials and methods Data were collected from farms supplying each of these supply chains, and life cycle assessment methodology was used to analyse
a range of impacts associated with producing (from plant propagation to harvesting and post-harvest cooling) and delivering
1 kg of lettuce to a UK Regional Distribution Centre (RDC). The downstream stages (i.e. retailing, consumption and waste management)
are the same regardless of the origin of the product and were omitted from the comparison. The impacts considered included
potential to induce global warming and acidification as well as three inventory indicators (primary energy use, land use and
water use). Qualitative data were collected in order to assess the consumer considerations of purchasing lettuce also during
winter.
Results Importation of Spanish field-grown lettuce into the UK during winter produced fewer greenhouse gas (GHG) emissions than lettuce
produced in UK-protected systems at that time (0.4–0.5 vs. 1.5–3.7 kg CO2-eq/kg lettuce in RDC). Refrigerated transport to the UK was an important element of the global warming potential associated
with Spanish lettuce (42.5% of emissions), whilst energy for heating dominated the results in UK-protected cultivation (84.3%
of emissions). Results for acidification were more variable and no overall trends are apparent. Results from qualitative social
analysis revealed complex and multidimensional meanings of freshness and suggested that the most striking seasonal variation
in vegetable/salad eating was a tendency to consume more salads in the summer and more cooked vegetables in the winter, thus
suggesting that in-home consumption alone cannot explain the rise in winter imports of lettuce to the UK.
Discussion UK field-grown lettuce had the lowest overall environmental impact; however, those lettuces are only available in summer,
so consumers therefore need to either accept the environmental impacts associated with eating lettuce in the winter or to
switch consumption to another food product in the winter. When lettuces were field-grown in Spain and then transported by
road to the UK, the overall impacts were similar to the UK field lettuces. The variation within farms of the same country
employing different cultivation regimes and practices was bigger than between farms of different countries.
Conclusions This paper has explored the environmental consequences of consuming lettuce year-round in the UK. Whilst recognising the small
sample size, the comparative analysis of the different supply chains does suggest that seasonality can be an important variable
when defining the best choice of lettuce from an environmental point of view.
Recommendations and perspectives Further studies considering more production sites and product types are required to obtain conclusions whose general validity
is clear and for different types of fresh produce. A clear distinction to be made in such studies is whether crops are produced
in open fields or under protection. New characterisation methods are needed for environmental impacts derived from the use
of key agricultural resources such as land and water. Social studies to investigate consumer preferences and the possibility
of moving to more seasonal diets should be an integral part of these studies using samples composed of both urban and rural
consumers and using a mixed methodology with both quantitative and qualitative components.
相似文献
Almudena HospidoEmail: |
19.
Assessing freshwater use impacts in LCA: Part I—inventory modelling and characterisation factors for the main impact pathways 总被引:2,自引:1,他引:1
Llorenç Milà i Canals Jonathan Chenoweth Ashok Chapagain Stuart Orr Assumpció Antón Roland Clift 《The International Journal of Life Cycle Assessment》2009,14(1):28-42
Background, aim and scope
Freshwater is a basic resource for humans; however, its link to human health is seldom related to lack of physical access to sufficient freshwater, but rather to poor distribution and access to safe water supplies. On the other hand, freshwater availability for aquatic ecosystems is often reduced due to competition with human uses, potentially leading to impacts on ecosystem quality. This paper summarises how this specific resource use can be dealt with in life cycle analysis (LCA).Main features
The main quantifiable impact pathways linking freshwater use to the available supply are identified, leading to definition of the flows requiring quantification in the life cycle inventory (LCI).Results
The LCI needs to distinguish between and quantify evaporative and non-evaporative uses of ‘blue’ and ‘green’ water, along with land use changes leading to changes in the availability of freshwater. Suitable indicators are suggested for the two main impact pathways [namely freshwater ecosystem impact (FEI) and freshwater depletion (FD)], and operational characterisation factors are provided for a range of countries and situations. For FEI, indicators relating current freshwater use to the available freshwater resources (with and without specific consideration of water ecosystem requirements) are suggested. For FD, the parameters required for evaluation of the commonly used abiotic depletion potentials are explored.Discussion
An important value judgement when dealing with water use impacts is the omission or consideration of non-evaporative uses of water as impacting ecosystems. We suggest considering only evaporative uses as a default procedure, although more precautionary approaches (e.g. an ‘Egalitarian’ approach) may also include non-evaporative uses. Variation in seasonal river flows is not captured in the approach suggested for FEI, even though abstractions during droughts may have dramatic consequences for ecosystems; this has been considered beyond the scope of LCA.Conclusions
The approach suggested here improves the representation of impacts associated with freshwater use in LCA. The information required by the approach is generally available to LCA practitionersRecommendations and perspectives
The widespread use of the approach suggested here will require some development (and consensus) by LCI database developers. Linking the suggested midpoint indicators for FEI to a damage approach will require further analysis of the relationship between FEI indicators and ecosystem health. 相似文献20.
Photosynthetic capacity of field-grown durum wheat under different N availabilities: A comparative study from leaf to canopy 总被引:1,自引:0,他引:1
Llorenç Cabrera-Bosquet Rossella Albrizio José Luis Araus Salvador Nogués 《Environmental and Experimental Botany》2009,67(1):145-152
The effect of N availability on photosynthetic capacity, growth parameters and yield was studied in field-grown durum-wheat plants at both the leaf and canopy levels. Two contrasting nitrogen levels (120 and 0 kg ha?1) were assayed in a randomised block design with nine replicates each. Total biomass was measured at anthesis and yield and its agronomical components at maturity. Photosynthetic measurements were performed 2 weeks after anthesis in two plots of each N treatment. Flag leaves were measured, using a LI-COR 6400 combined with the chlorophyll fluorescence meter, and the whole canopy by measuring CO2 and H2O fluxes in an innovative canopy-chamber system. We showed a clear increase in photosynthetic gas exchange and chlorophyll contents with N fertilisation at both canopy and leaf levels. As a consequence the increase in yield as response to N fertilisation seems the result of a larger green leaf area combined with a higher photosynthetic capacity of the leaves attributable to an increase in the maximum carboxylation velocity of Rubisco. Moreover gas-exchange measurements of the flag leaf during grain filling seem to provide a realistic characterisation, not just of the photosynthetic performance of the crop, but also about the impact of N availability on yield. Thus, measurements performed on the flag leaf matched those at the canopy level, with proportional increases in terms of gas exchange and chlorophyll content, providing a fast, cheap and reliable estimation of canopy photosynthesis and the grain yield attained by the crop. 相似文献