Calvo, E., Calatayud, V., Cerveró, J., Martin, C., Sensibilidad al ozono de especies mediterráneas y cargas críticas. 4ª Reunión de GRACCIE en Salamanca. 2011
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Mrs Kokadir enjoys gardening in her backyard and sharing about beautiful wildflowers for fellow gardeners.
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Generally global warming refers to an increase in average global temperatures. There are many gases like nitrous oxide, methane, nitrogen in atmosphere which keeps the earth warm and cause global warming or greenhouse effect. Global warming is caused by natural as well as human activities. There are number of natural factors responsible for climate change. Some of the most prominent are volcanoes, ocean currents, forest fires etc. Among human activities, emissions of greenhouse gases, industrialization, deforestation, fuel burning, etc. are most important factor contributing towards global warming. It is not new that global warming can affect agriculture through their direct and indirect effects on the crops, soils, livestock, and pests. So, because of global warming insects are effected in many ways. Increased temperature has resulted in increased northward migration of some insects, insect development rate and oviposition, potential for insect outbreaks, invasive species introductions and insect extinctions because, insects are able to respond rapidly to climate changes and adapt to the changing environment due to high reproductive potential and relatively short generation time. Here are some examples of researches conducted in ISRAEL of the species of insects named (Orius). These are the bugs which are mostly generalist predators commonly found in flowers of herbaceous vegetation In this study, there was a Comparison of the relative abundance of Orios species revealed significant differences among years (G12= 1060.2, P,0.0001). The relative abundance of O. laevigates has decreased from 50%, 38% and 60% during 1940–59, 1960–79 and 1980–99, respectively, to 4–6% during 2001–2 and the present survey. In contrast, the relative abundance of O. abidingness has increased gradually from 9% and 1% during 1940–59 and 1960–79, respectively, to 26% during 1980–99 and 65% and 62% in 2001–2 and in the present survey, respectively. There are other effect on the insects listed below
· Effect of global warming on insect biology: Temperature is probably the single most important abiotic factor influencing insect biology. Pests may become more active than they currently are, thus posing the threat of greater economic losses to farmers. It has been estimated that wit.
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Summary of the Climate and Energy Policy of Australia
Calvo_etal_2011
1. 4ª Reunión GRACCIE, Salamanca septiembre 2011
Sensibilidad al Ozono de Especies
Mediterráneas y Cargas Críticas
Esperanza Calvo, Vicent Calatayud,
Jùlia Cerveró, Carmen Martin
2. Ozono como gas de efecto invernadero
-Tropospheric ozone is an air pollution of major concern for
vegetation. Model predictions, using IPCC scenarios, suggest
that background levels of this pollutant will increase
worlwide in the future.
-Ozone Impairs assimilation reduces C sequestration, causes
leaf visible injuries, reductions on grown and productivity. It may
change the species composition of natural plant communitites.
Ozone reduces resilience to pest and diseases and increase the
sensitivity to drought.
3. Physiological, anatomical and biomass partitioning
responses to ozone in the mediterranean endeminc
plant Lamottea dianae
Calatayud,V., Garcia-Breijo, F.J., Cerveró J., Reig-Armiñana, J., Sanz M.J.
Ecotoxicology & Environmental Safety 74 (2011), 1131–1138.
4. Calatayud et al., 2011-Increasing ozone levels in eastern
Spain might represent a threat for
endemic plant Lamottea dianae.
Spring ozone concentrations in
mediterranean area might affect CO2
assimilation capacity and reducing
WUE and possibly root system
development, It contributes to
reducing the capacity of theese plants
to whitstand the subsequent drier
summer conditions
a
a
a
b
a
a
0
10
20
30
40
50
60
70
80
90
100
Total
Biomass
Above ground
B.
Below ground
B.
gDW
CF
NF+30
*
(*)
*
0
2
4
6
8
10
12
14
16
15 29 43 57 72 86 99
Days after starting fumigation
Accumulateddryweightof
senescentleaves(g)
CF
NF+30
5. Lower number of flowers per plant
Less seeds per plant and flower
García-Breijo et al., 2005
Results with regard to control treatment. More
reductions in total seed and also in viable seed,
per plant and flower.
*(
*)
*
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
21 30 36 42 48 57 64 71 78 84
Days After Starting Fumigation
NumberofFlowersperPlant
CF
NF+30
6. Ozono como gas de efecto invernadero
Mediterranean broadlef evergreen
species are comparatively ozone-
tolerant. Sensitivity of evergreen
species to ozone is largely under-
investigated.
Ozone effects on the plants depends
not only on the pollutan dose entering
throught the stomata but also on the
balance between the flux and the
effectiviness of the defence
mechanisms to cope oxidative estress
7. Contrasting ozone sensitivity in related
evergreen and decidous shrubs
Calatayud, V., Marco, F., Cerveró, J., Sánchez-Peña, G., Sanz, M.J.
Environmental Pollution 158 (2010), 3580–3587.
8. Hypotheses:
Evergreen species are more ozone
tolerant that related decidous
species
Stomatal conductance can explain
differences in ozone sensitivity
Sensitivity of species is related to its
constitutive or induced antioxidant
pool
Calatayud et al., 2010
Decidous
Pistacia terebinthus
Viburnum lantana
Evergreen
Pistacia lentiscus
Viburnum tinus
9. 0
5
10
15
20
25
30
35
40
45
50
0 10 20 30 40 50 60 70 80 90 100 110 120
Days after starting of fumigation
PlantInjuryIndex
Pistacia lentiscus
Pistacia terebinthus
Viburnum tinus
Viburnum lantana
Visible injury was common in the two
deciduous species, but only rarely
observed in evergreen ones
Calatayud et al., 2010
Decidous
Evergreen
10. Decidous species present a constitutively higher presence
of superoxide and peroxide generation
Calatayud et al., 2010
DecidousEvergreen Evergreen
11. Mediterranean forest ecosystems.
Can be related the ozone responses to
leaf traits?
Coriaceous and scerophyllous leaves,
lignified walls, and few intercellular
spaces, less cell space exposed
complicate ozone flux into the cells
12. Responses of evergreen and decidous Quercus
species to enhanced ozone levels
Calatayud,V., Cerveró J., Calvo, E., García-Breijo, F.J., Reig-Armiñana, J.,
Sanz M.J.
Environmental Pollution 74 (2011), 1131–1138.
13. Hypotheses
Ozone sensitivity in these especies is the result of
interaction between ozone uptake and species-
especific leaf characteristics.
Calatayud et al., 2011
14. Evergreen Decidous
Q. ilex Q. faginea Q. robur Q. pyrenaica
Leaf traits
of the
species
Drought tolerance
Sclerophyllia
Leaf Size
Thickness
Calatayud et al., 2011
16. Calatayud et al., 2011
Decidous Quercus (robur and pyrenaica) show ozone visible symptoms
on the leaves.
Gas exchange results underline the relative high tolerance of Q. ilex to
enhanced ozone levels.
Q. pyrenaica, the specie showing the earliest and severe symptoms and
the strongest effects on assimilation.
The initial hypotheses was basically confirmed
17. New Stomatal flux-based critical levels for
ozone effects on vegetation
Mills, G., Pleijel, H., Braun S., Büker, P., Bermejo, V., Calvo, E.,
Danielsson, H., Emberson, L., González-Fernández, I., Grünhage, L.,
Harmens, H., Hayes, F., Karlsson, P.E., Simpson, D.,
Atmospheric Environment 45 (2011), 5064–5068.
18. Ozone levels has increased over the last 100 years, with current and future effects
on health ecosystems and vegetation
Visible injury records on 30 different crops and 80 species of semi-natural
vegetation
Robust methodology for mapping the areas where ozone damage occurs.
Mills et al., 2011
19. Mills et al., 2011
CONCEPTO DE CARGA CRITICA
La concentración, exposición acumulada o flujo acumulado, de un contaminante
por encima del cual se producfen efectos directos sobre la vegetación más
sensible, según el estado de conocimiento actual
20. AOT40
(Accumulated Ozone Exposure over a
Threshold of 40 ppb)
O 3
PODy
(Phytotoxic
Ozone Dose over a Y threshold)
Exposure or Dose response function
Ozone Critical Levels
UNECE Convention
Ozone Stomatal Flux modelling (DO3SE)
gsto = gmax * [fphen * flight] * max [fmin,
(ftemp * fvpd)]
21. Y = 1.00 - 0.024 * POD6
R
2
= 48,6%
p < 0.01
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 5 10 15 20
POD6, mmol m-2
Relativeyield
IT
SP
Valor umbral de flujo de
ozono que produce una
pérdida en la producción
de tomate de un 5% =
2.3 mmol m-2
Carga Crítica: Flujo de ozono
22. Species/Vegetation
type
Wheat Wheat Wheat Potato Tomato
Critical Level
(PODy mmol m-2)
POD6 POD6 POD6 POD6 POD6
Effect parameter Grain yield 1000 grain
yield
Protein yield Tuber yield Fruit yield
% of reduction for CL 5 5 5 5 5
Time period 200ºC days before anthesis to 700ºC days
after anthesis
1130ºC days
starting at plant
emergence
3.5 months
Countries involved in
experiments
4 3 3 4 2
Number of data (nº
of cultivars)
36 (5) 33 (4) 33 (4) 17 (1) 24 (9)
Response Function RY = -0.038
POD6+1
RY = -0.033
POD6+1
RY = -0.025
POD6+1.01
RY = -0.013
POD6+1.01
RY = -0.024
POD6+1
R2 0.84 0.71 0.63 0.76 0.49
P <0.001
Mills et al., 2011
Dose Response functions for horticulturan and agricultural
crops
23. Responses of evergreen and decidous Quercus species
to enhanced ozone levels
Calatayud et al., 2011
Critical Levels
Decidous oaks
Based on AOT40 18 ppm.h
Based on POD1.6 16 mmol m-2
Critical Levels for Quercus ilex
2.5-3.5 higher than decidous
25. Futuras Líneas de
investigación
Flujos de ozono a nivel de ecosistema con
Eddy-Covariance
Estudio de interacciones entre ozono, y salinidad
en agua de riego. El injerto como paliativo
Interacciones entre ozono y estrés hídrico
27. While with crops and other decidous species exposure o dose response functions describing
the ozone effects have been stablished. These functions are still lacking for typical
Mediterranean species.
Results from Quercus experiment will be reported to UNECE convection for developing new
Critical Levels to mediterranean evergreen forest
New Critical Level for horticultural crop (tomato) has been estimated based on ozone flux
modelling and reported to UNECE Convection.
-Increasing ozone levels in eastern Spain might represent a threat for some endemic plant.
Spring ozone concentrations in mediterranean area might affect CO2 assimilation capacity
and reducing WUE and possibly root system development, It contributes to reducing the
capacity of theese plants to whitstand the subsequent drier summer conditions
Mediterranean broadlef and evergreen species are comparatively ozone-tolerant. Sensitivity
of evergreen species to ozone is largely under-investigated.
Coriaceous and scerophyllous leaves, lignified walls, and few intercellular spaces, less cell
space exposed complicate ozone flux into the cells. Ozone sensitivity in mediterranean
species not only depends on stomatal conductance. Antioxidant systems and leaf traits can
be also considered.
The adverse effects of ozone on biomass production and the consequence
for the global carbon and water cycles need to be included in global climate
modelling.
Editor's Notes
Les concentracions d’ozó de fons hemisfèric, aquelles registrades lluny de les emissions antropogèniques de precursors d’ozó, han augmentat fins a 5 vegades des de finals del segle XIX (Nolle et al., 2005). Aquest increment està relacionat en l’augment de l’emissió d’hidrocarburs i d’òxids de nitrogen degut a l’increment de l’ús de combustibles fòssils. Els esforços internacionals per a disminuir les concentracions d’ozó han aconseguit que es reduïsquen els pics màxims (disminuint un 36 % els precursors de l’ozó (EEA, 2007)) però no han influït sobre les concentracions de fons hemisfèric (Coyle et al., 2003), que continua augmentant a un ritme de 0,5-2 % anual en algunes zones de l’hemisferi nord (Vingarzan, 2004).
Les prediccions del model del Panell Intergovernamental del Canvi Climàtic (IPCC), en el que s’ha emprat diferents escenaris, indiquen que els nivells de l’ozó augmentaran en tot el món en el futur (Vingarzan, 2004). L’ozó, a part de ser un contaminant tòxic també és un gas poderós d’efecte hivernacle que contribueix al forçament radiatiu positiu (Bytnerowicz et al., 2007; IPCC, 2007). El forçament radiatiu és el canvi de flux net d’energia radiativa cap a la superfície de la Terra mesurat en la vora superior de la troposfera (12000 m sobre el nivell de la mar) com a resultat de canvis interns en la composició de l’atmosfera o canvis en l’aportament extern d’energia solar, s’expressa en W m-2. El forçament radiatiu positiu contribueix a calfar la superfície de la Terra, mentre que el negatiu afavoreix el seu refredament. El forçament radiatiu positiu més important és el del CO2, seguit pel metà (CH4), els halocarbons, l’ozó troposfèric i el diòxid de nitrogen. Per altra banda, la disminució observada en la concentració de l’ozó estratosfèric ha generat un xicotet forçament radiatiu negatiu (favorable al refredament de la superfície)
Como son las respuestas del bosque mediterráneo ante la contaminación por ozono?
Constitutivamente las deciduas tienen más SOD y GPX que sus congenericas. La formación de ROS derivada de la entrada del Ozono en la hoja, provoca la actividad enzimática, se eleva la barra blanca, que desencadena en respuestas de estrés como los síntomas visibles en hojas.
En las perennes su estado redox inicial es más favorable para contrarrestar la accion de las ROS y mantener por debajo del umbral el desencadenamiento de la presencia de síntomas en las hojas. Además las especiales características de sus hojas, más coriaceas con menos espacios intercelulares, furtemente lignificadas dificultan el flujo de ozono hacia las hojas.
El género quercus incluye especies caducas y perennnes. En España las especies más relevantes son Q. ilex, pyrenaica, robur y faginea. Q robur es muy frecuente en Europa pero ausente en la cuenca mediterranea debido al estrés hídrico. Estas especies muestran marcadas diferencias entre las hojas.
Con la modelización se consiguen valores horarios de conductancia estomática para una especie en un territorio dado. Conociendo la gmax, fenologia, radiación, temperatura, VPD (Déficit de presión de vapor) y SWC (Soil Water Content).
A partir de estos valores, se combinan con las concentraciones de ozono y se obtienen flujos horarios de ozono.
Se acumulan durante el periodo de tiempo que se desee calcular y se estiman las funciones de dosis respuesta.
El concepto de flujo de ozono es, actualmente, la forma más cercana a estimar las dosis de ozono a las que está sometido el vegetal. El flujo está regulado por los gradientes de concentración y la resistencia. La conductancia estomática es la inversa de la resistencia que ofrece la hoja a la penetración de un gas en su interior. De manera genérica, la conductancia estomática (gs) se refiere a la salida de vapor de agua por la evapotranspiración de la planta. Sin embargo cuando, los estomas están abiertos (pérdida de agua para la planta) pueden absorberse otros gases que hay en la planta, por ejemplo el ozono.
Ley de Fick
FluxO3 = 0.6999 x ([O3]e-[O3]i) x gs
La aplicación de este concepto implica conocer el valor de ozono, y de conductancia estomática para un sinfín de especies vegetales
A partir de datos fácilmente mesurables, y que son las principales condiciones climáticas que gobiernan el grado de apertura estomática, se define un modelo de conductancia estomática basado en el modelo de fotosíntesis de Purvis.
La ecuación expresa un modelo multiplicativo en el que cada variable ejerce una influencia significativa de reducción de la conductancia estomática.
Para el cálculo de los flujos de ozono modelizados se precisan datos de Temperatura, velocidad del viento, radiación, contenido hídrico del suelo y concentración de ozono. Debe conocerse la vegetación de la zona y calcular experimentalmente la fenología y el valor de conductancia máximo (gmax)
Estos datos se remiten a la conveccion para los mapeos
Estos datos se remiten a la conveccion para los mapeos
La estimulación de la producción primaria causada por niveles elevados de CO2 y la capacidad de sumideros de los ecosistemas se puede ver afectada por el O3
El ozono representa el 10% del total de forzamiento radiativo provocado por los GEIS
Les concentracions d’ozó de fons hemisfèric, aquelles registrades lluny de les emissions antropogèniques de precursors d’ozó, han augmentat fins a 5 vegades des de finals del segle XIX (Nolle et al., 2005). Aquest increment està relacionat en l’augment de l’emissió d’hidrocarburs i d’òxids de nitrogen degut a l’increment de l’ús de combustibles fòssils. Els esforços internacionals per a disminuir les concentracions d’ozó han aconseguit que es reduïsquen els pics màxims (disminuint un 36 % els precursors de l’ozó (EEA, 2007)) però no han influït sobre les concentracions de fons hemisfèric (Coyle et al., 2003), que continua augmentant a un ritme de 0,5-2 % anual en algunes zones de l’hemisferi nord (Vingarzan, 2004).
Les prediccions del model del Panell Intergovernamental del Canvi Climàtic (IPCC), en el que s’ha emprat diferents escenaris, indiquen que els nivells de l’ozó augmentaran en tot el món en el futur (Vingarzan, 2004). L’ozó, a part de ser un contaminant tòxic també és un gas poderós d’efecte hivernacle que contribueix al forçament radiatiu positiu (Bytnerowicz et al., 2007; IPCC, 2007). El forçament radiatiu és el canvi de flux net d’energia radiativa cap a la superfície de la Terra mesurat en la vora superior de la troposfera (12000 m sobre el nivell de la mar) com a resultat de canvis interns en la composició de l’atmosfera o canvis en l’aportament extern d’energia solar, s’expressa en W m-2. El forçament radiatiu positiu contribueix a calfar la superfície de la Terra, mentre que el negatiu afavoreix el seu refredament. El forçament radiatiu positiu més important és el del CO2, seguit pel metà (CH4), els halocarbons, l’ozó troposfèric i el diòxid de nitrogen. Per altra banda, la disminució observada en la concentració de l’ozó estratosfèric ha generat un xicotet forçament radiatiu negatiu (favorable al refredament de la superfície)