Profs. Josep Peñuelas and Iolanda
Filella from the Global Ecology Unit (CSIC-CREAF) have been named in the Stanford University- Elsevier list of most-cited scientists in various
disciplines worldwide. The database is created by experts at Stanford
University and includes 100,000 top-scientists according to standardized
information on citations, h-index, co-authorship adjusted hm-index, citations
to papers in different authorship positions and a composite indicator (updated
to citation year 2019).
According to this database
and for the year 2019:
Prof. Josep Peñuelas has been nominated among the four hundred most
influential scientists in all fields and among the ten most influential
scientists in ecological and environmental sciences (Meta-Research Innovation
Center at Stanford – METRICS)
Prof. Iolanda Filella has been nominated among the eight hundred most
influential scientists in plant biology (Meta-Research Innovation Center at
Stanford – METRICS)
Prof. Jordi Sardans had been nominated among the six hundred most
influential scientists in ecological and environmental sciences (Meta-Research
Innovation Center at Stanford – METRICS)
A new study published in Science reveals
that the fertilizing effect of excess CO2 on vegetation is decreasing
worldwide. The lack of water and nutrients limit the greening observed
in recent years and can cause CO2 levels in the atmosphere to rise
rapidly, temperatures to increase and there to be increasingly severe
changes in the climate.
The
lack of water and nutrients limit the greening observed in recent years
and can cause CO2 levels in the atmosphere to rise temperatures to
increase and to increase severe changes in the climate. Image: Public
Domain
Vegetation has a key role in mitigating climate change because it reduces the excess CO2
that we humans emit into the atmosphere. Just as when sportsmen and
women are doped with oxygen, plants also benefit from the large amounts
of CO2 that accumulate in the atmosphere. If more CO2 is available, they photosynthesize and grow more, which is called the fertilizing effect of CO2.
When plants absorb this gas to grow, they remove it from the atmosphere
and it is sequestered in their branches, trunk or roots.
An article published in Scienceon December 2020 shows that this fertilizing effect of CO2 is decreasing worldwide, according to the text co-directed by Professor Josep Peñuelas of the CSIC at CREAF and Professors Songhan Wang (first author of the article) and Yongguang Zhang of the University of Nanjin, with the participation of CREAF researchers Jordi Sardans and Marcos Fernández. The study, carried out by an international team, concludes that the reduction has reached 50% progressively since 1982
due basically to two key factors: the availability of water and
nutrients. “There is no mystery about the formula, plants need CO2, water and nutrients in order to grow. However much the CO2
increases, if the nutrients and water do not increase in parallel, the
plants will not be able to take advantage of the increase in this gas”,
explains Professor Josep Peñuelas. In fact, three years ago Prof. Peñuelas already warned in an article in Nature Ecology and Evolution that the fertilising effect of CO2 would not last forever, that plants cannot grow indefinitely, because there are other factors that limit them.
If the fertilizing capacity of CO2 decreases, there will
be strong consequences on the carbon cycle and therefore on the climate.
Forests have received a veritable CO2 bonus for decades,
which has allowed them to sequester tons of carbon dioxide that enabled
them to do more photosynthesis and grow more. In fact, this increased
sequestration has managed to reduce the CO2 accumulated in the air, but now it is over. “These
unprecedented results indicate that the absorption of carbon by
vegetation is beginning to become saturated. This has very important
climate implications that must be taken into account in possible climate
change mitigation strategies and policies at the global level. Nature’s
capacity to sequester carbon is decreasing and with it society’s
dependence on future strategies to curb greenhouse gas emissions is
increasing”, warns Josep Peñuelas.
The study published in Science has been carried out using
satellite, atmospheric, ecosystem and modelling information. It
highlights the use of sensors that use near-infrared and fluorescence
and are thus capable of measuring vegetation growth activity.
Less water and nutrients
According to the results, the lack of water and nutrients are the two factors that reduce the capacity of CO2 to improve plant growth. To reach this conclusion, the team based itself on data obtained from hundreds of forests studied over the last 40 years.
“These data show that concentrations of essential nutrients in the
leaves, such as nitrogen and phosphorus, have also progressively
decreased since 1990,” explains researcher Songhan Wang.
The team has also found that water availability and temporal changes
in water supply play a significant role in this phenomenon. “We have
found that plants slow down their growth, not only in times of drought,
but also when there are changes in the seasonality of rainfall, which is
increasingly happening with climate change,” explains researcher Yongguang Zhang.
The quantity, quality, and type (e.g., animal and vegetable) of human food and beverages have been correlated with cancer and life expectancy, although mostly at the population level and with many uncertainties. In a new study published in the journal Environmental Research and Human Health authors shed light on this association at country level. Picture source https://www.helpguide.org/
The quantity, quality, and type (e.g., animal
and vegetable) of human food have been correlated with human health, although
with some contradictory or neutral results. We aimed to shed light on this
association by using the integrated data at country level.
In a new study published in the journal Environmental Research and Human Health authors
hypothesized that higher N intake, lower N:P intake ratios, terrestrial animal
food, and alcoholic beverages would be associated with cancer and shorter life
expectancy (LE), whereas on the contrary, aquatic animals and vegetables would
be associated with less cancer and longer LE.
The study correlated elemental (nitrogen (N)
and phosphorus (P)) compositions and stoichiometries (N:P ratios), molecular (proteins)
and energetic traits (kilocalories) of food of animal (terrestrial or aquatic)
and vegetable origin, and alcoholic beverages with cancer prevalence and
mortality and LE at birth at the country level.
Researchers used the official databases of
United Nations (UN), Food and Agriculture Organization of the United Nations
(FAO), Organization for Economic Co-operation and Development (OECD), World Bank,
World Health Organization (WHO), U.S. Department of Agriculture, U.S.
Department of Health, and Eurobarometer, while also considering other possibly involved
variables such as income, mean age, or human development index of each country.
The per capita intakes of N, P, protein, and
total intake from terrestrial animals, and especially alcohol were
significantly and positively associated with prevalence and mortality from
total, colon, lung, breast, and prostate cancers. In contrast, high per capita
intakes of vegetable N, P, N:P, protein, and total plant intake exhibited
negative relationships with cancer prevalence and mortality. However, authors
highlighted that a high LE at birth, especially in underdeveloped countries was
more strongly correlated with a higher intake of food, independent of its
animal or vegetable origin, than with other variables, such as higher income or
the human development index.
“Our analyses, thus, yielded four generally consistent
conclusions. First, the excessive intake of terrestrial animal food, especially
the levels of protein, N, and P, is associated with higher prevalence of
cancer, whereas equivalent intake from vegetables is associated with lower
prevalence. Second, no consistent relationship was found for food N:P ratio and
cancer prevalence. Third, the consumption of alcoholic beverages correlates
with prevalence and mortality by malignant neoplasms. Fourth, in underdeveloped
countries, reducing famine has a greater positive impact on health and LE than
a healthier diet”, concluded Prof. Josep Penuelas from CREAF-CSIC Barcelona.
Reference: Penuelas, J., Krisztin, T., Obersteiner, M., Huber,
F., Winner, H., Janssens, I.A., Ciais, P., Sardans, J. 2020. Country level
relationships of the human intake of N and P, animal and vegetable food and
alcoholic beverages with cancer and life expectancy. Environmental Research and Human Health, 2020, 17, 7240;
doi:10.3390/ijerph17197240.
Ecological processes occurring at the ecosystem and foliar levels in a natural (not polluted) ecosystem (A) versus an ecosystem disturbed by increased levels of O3, figure shows the effects of elevated ozone (O3) on aboveground ecosystem processes. Figure by Agathokleous et al. Science Advances, 2020)
Elevated tropospheric ozone concentrations induce adverse effects in plants. We reviewed how ozone affects (i) the composition and diversity of plant communities by affecting key physiological traits; (ii) foliar chemistry and the emission of volatiles, thereby affecting plant-plant competition, plant-insect interactions, and the composition of insect communities; and (iii) plant-soil-microbe interactions and the composition of soil communities by disrupting plant litterfall and altering root exudation, soil enzymatic activities, decomposition, and nutrient cycling. The community composition of soil microbes is consequently changed, and alpha diversity is often reduced.
The effects depend on the environment and vary across space and time. We suggest that Atlantic islands in the Northern Hemisphere, the Mediterranean Basin, equatorial Africa, Ethiopia, the Indian coastline, the Himalayan region, southern Asia, and Japan have high endemic richness at high ozone risk by 2100.
Reference: Agathokleous, E., Feng, Z., Oksanen, E., Sicard, P., Wang, Q., Saitanis, C.J., Araminiene, V., Blande, J.D., Hayes, F., Calatayud, V., Domingos, M., Veresoglou, S.D., Peñuelas, J., Wardle, D.A., De Marco, A.D., Li, Z., Harmens, H., Yuan, X., Vitale, M., Paoletti, E. 2020. Ozone affects plant, insect, and soil microbial communities: A threat to terrestrial ecosystems and biodiversity. Science Advances, 6(33): eabc1176. Doi: 10.1126/sciadv.abc1176
Un equip internacional –amb l’investigador del CSIC al CREAF Josep Peñuelas– explora els factors decisius del comportament vegetal i com incloure’ls als models predictius. El resultat es publica a Nature Plants i vol millorar la comprensió del cicle global del carboni i els serveis ecosistèmics i el seu futur si els boscos canvien pel canvi climàtic.
Bosc de coníferes. Public Domain.
“Hem demostrat que si representem els principis d’evolució, autoorganització i maximització d’entropies (l’organització aleatòria d’alguns processos naturals) en els models, podrem predir millor el comportament de les plantes complexes i la vegetació en general en relació amb els canvis ambientals”, explica Josep Peñuelas.
Aquests factors ja s’han utilitzat anteriorment per separat per entendre aspectes concrets del funcionament de les plantes. Però les implicacions que tenen quan es combinen encara no s’havien analitzat a fons. Aprofundir-hi és important per conèixer millor com afectarà el canvi climàtic a aquestes dinàmiques.
Franklin O, Harrison S, Dewar R, Farrior C, Brännström A, Dieckmann U, Pietsch S, Falster D, Penuelas J, et al. (2020). Organizing principles for vegetation dynamics. Nature Plants DOI: 10.1038/s41477-020-0655-x
Un equip d’investigació internacional on ha participat en Josep Peñuelas explora els factors que més afecten el comportament de les plantes i com es poden incloure als models predictius per perfeccionar-los. L’estudi, publicat a Nature Plants, vol millorar la comprensió del cicle global del carboni i els serveis ecosistèmics i quin futur els espera si els boscos canvien davant el canvi climàtic.
Bosc de coníferes. Public Domain.
“Hem trobat que si representem els principis d’evolució, autoorganització i maximització d’entropies (l’organització aleatòria d’alguns processos naturals) en els models, podrien predir millor el comportament de les plantes complexes, i la vegetació en general, en relació amb els canvis ambientals”, explica en Josep Peñuelas, investigador del CSIC al CREAF.
Aquests factors que proposa l’estudi ja s’han utilitzat anteriorment per separat per entendre aspectes concrets del funcionament de les plantes, però les implicacions que tenen quan es combinen encara no s’havien entès del tot. Profunditzar-hi és important per conèixer millor com afectarà el canvi climàtic a aquestes dinàmiques.
Franklin O, Harrison S, Dewar R, Farrior C, Brännström A, Dieckmann U, Pietsch S, Falster D, Penuelas J, et al. (2020). Organizing principles for vegetation dynamics. Nature Plants DOI: 10.1038/s41477-020-0655-x
Afforestation is considered an effective strategy for increasing carbon sequestration and mitigating climate change and it has undoubtedly increased C stored in biomass. Afforestation has been widely implemented in many countries since the 1990s, increasing the area of planted forests globally by about 1.05 × 108 ha Picture by Pixabay
Afforestation is the term used to refer the establishment of forests where previously there have been none, or where forests have been missing for a long time and has been proposed as an efficient method for removing carbon dioxide and mitigating climate change. The success of the goals of mitigation, however, depends on both the area of trees planted and the potential for carbon (C) sequestration of each afforestation. However, afforestation-induced changes in soil organic C (SOC) are poorly quantified due to the paucity of large-scale sampling data.
In a new
study published in the journal Nature
plants authors provide the first comprehensive assessment of the
afforestation impact on SOC stocks with a pairwise comparative study of samples
from 619 control-and-afforested plot pairs in northern China.
Authors found
context-dependent effects of afforestation on SOC: afforestation increases SOC
density (SOCD) in C-poor soils but decreases SOCD in C-rich soils, especially
in deeper soil. Thus, the fixed biomass/SOC ratio assumed in previous studies
could overestimate the SOC enhancement by afforestation. “By extrapolating the
sampling data to the entire region, we estimate that afforestation increased
SOC stocks in northern China by only 234.9 ± 9.6 TgC over the last three
decades. The study highlights the importance of including pre-afforestation
soil properties in models of soil carbon dynamics and carbon sink projections”
explained Dr. Hong from the Sino-French Institute for Earth System Science,
College of Urban and Environmental Sciences, Peking University, China.
The results
of the study strongly suggest that estimated afforestation C sink potentials
that do not account for background soil C stocks or the potentially negative
effects of afforestation is overly optimistic. The authors claim that these
findings also indicate that the assumption of a fixed ratio between soil and
biomass C, which has been widely used in previous studies for estimating soil C
stocks is unreliable.
“According to this study pre-afforestation soil
properties and original vegetation type need to be included in models of soil
carbon dynamics; and extensive global-scale field investigations are required
to improve the estimation of soil carbon stocks. Furthermore, the dependence of
soil C changes on background soil C and tree species highlights the importance
of site and species choices for maximizing afforestation C sequestration” said
Prof. Josep Penuelas from CREAF-CSIC Barcelona.
Reference: Hong, S., Yin, G.,
Piao, S., Chen, A., Cong, N., Dybzinski, R., Peñuelas, J., Zeng, H. 2020.
Divergent responses of soil organic carbon to afforestation. Nature Sustainability, doi:
https://doi.org/10.1038/s41893-020-0557-y.
Un estudi de l’ICTA, el CREAF, el CTFC i la UAB caracteritza per primera vegada la química forestal de l’aire per sota la copa dels arbres en un alzinar mediterrani. Les concentracions màximes de monoterpens, els compostos orgànics volàtils relacionats amb la salut humana, es produeixen al juliol i agost, a primera hora del matí i de la tarda.
Montseny. Autor: Pixel (Wikimedia Commons)
La recerca Human Breathable Air in a Mediterranean Forest: Characterization of Monoterpene Concentrations under the Canopy realitzada per l’investigador Albert Bach, de l’Institut de Ciència i Tecnologia Ambientals de la Universitat Autònoma de Barcelona (ICTA-UAB), ha comprovat que els monoterpens que emeten les plantes dins d’un alzinar tenen nivells màxims durant el juliol i l’agost. Els monoterpens són les fragàncies que emeten les plantes per comunicar-se, fer fora depredadors o captar l’atenció dels pol·linitzadors, entre d’altres. Són compostos orgànics volàtils actualment en estudi per les seves propietats antiinflamatòries, neuroprotectores i antitumorogèniques. En la recerca hi han col·laborat els investigadors del CREAF Joan Llusià, Iolanda Filella i Josep Peñuelas, juntament amb altres del Centre de Ciència i Tecnologia Forestal de Catalunya (CTFC), del Consejo Superior de Investigaciones Científicas (CSIC) i del Departament de Geografia de la UAB.
L’estudi, impulsat per la Fundació Bancària La Caixa i publicat a l’ International Journal of Environmental Research and Public Health, demostra que al bosc podem trobar aquests compostos a l’aire d’una forma molt variable. N’hi haurà més o menys depenent de l’estació de l‘any i l’hora del dia, sobretot segons la temperatura que faci, la radiació solar i la humitat. De fet, l’estudi ha comprovat que les màximes concentracions es produeixen durant el juliol i l’agost a primera hora del matí (de 6 a 8h) i de la tarda (de 13 a 15h), quan fa més calor i sol.
Els resultats suggereixen que, durant l’estiu, les persones que caminen per aquest tipus de boscos estarien subjectes a una major absorció potencial de monoterpens en el seu torrent sanguini, especialment a primera hora del matí i a partir del migdia. Les concentracions obtingudes són similars o majors que en d’altres estudis que han demostrat la relació entre aquests compostos i la salut de les persones, no només al laboratori sinó també al bosc.
Bosc i salut
Quan estem en contacte amb el bosc experimentem una sèrie d’efectes en la nostra salut en general: als sistemes cardiovascular, immunitari, respiratori i nerviós, als que s’hi afegeixen canvis en el benestar fisiològic i psicològic.
Tot i el seu paper rellevant al binomi bosc-salut, aquests compostos han estat poc estudiats per sota de la copa dels arbres, que és on té lloc la interacció amb les persones. Per això, aquest estudi pioner obre un nou marc de recerca als boscos mediterranis i constitueix una aportació important per a la comunitat científica i de la sanitat pública.
According to a new study published in the journal Nature Plants authors suggest that the first of the potential factors triggering a highly variable seed production could have been, before wind pollination and predators evolved, nutrient scarcity. Picture by Pixabay
Nutrient scarcity, and climate, are long
existing evolutionary forces that have selected for multiple plant traits and
have constrained the physiology of plants since their early development.
In a new study published in the journal Nature plants authors propose a
mechanism by which nutrient scarcity may select for highly variable seed
production, with weather patterns inducing masting synchrony across
populations; they also discuss why wind-pollination and predator satiation
cannot be the only selective pressures that select for highly variable
reproduction.
Nutrient availability is a direct determinant
of the mean fruit production in agriculture and in the wild. In this study, authors
discuss why low nutrient availability may have been an important factor
selecting for highly variable and synchronized seed production, the latter in
combination with adaptation to variability in long-term climate patterns.
According to the authors, given the fact that
temporally variable sexual reproduction in nature seems to be common, they
conclude that factors others than wind pollination and predator satiation may
have played a role in shaping this reproductive trait. “We suggest that one of
these potential factors triggering a highly variable seed production, before
wind pollination and predators evolved, may have been nutrient scarcity because
of its role in determining the physiology of a broad range of organisms”, said
Dr. Fernández-Martínez from University of Antwerp and collaborator of the
Global Ecology Unit.
“This mechanism, which could have originated
during the early evolution of plants, may explain why, under low nutrient
availability, nutrient-conservative plants with highly variable reproduction
may have been preferentially selected in comparison to nutrient-spending plants
(with more constant reproduction).” said Prof. Josep Penuelas from CREAF-CSIC
Barcelona.
Reference: Fernández-Martínez,
M., Sardans, J., Sayol, F., LaMontagne, J.M., Bogdziewicz, M., Collalti, A.,
Hacket-Pain, A., Vacchiano, G., Espelta, J.M., Peñuelas, J., Janssens, I.A.
2020. Reply to: Nutrient scarcity cannot cause mast seeding. Nature Plants. DOI: 10.1038/s41477-020-0703-6.
According to a new study published in the journal Nature Ecology and Evolution the increase in gymnosperm sensitivity to drought suggests that their increasing intrinsic water use efficiency may not have alleviated the impacts of drought stress. Picture by Shutterstock
The frequency and intensity of droughts have
grown over the decades, leading to increased forest decline. The response of
forest to drought can be evaluated by its sensitivity to drought (resistance)
and the post-drought recovery rate (resilience). However, it remains uncertain
how drought resistance and resilience of forests have changed across the space
and over time under climate change.
In a new study published in the journal Nature Ecology and Evolution authors assessed
the spatio-temporal dynamics of forest resistance and resilience to drought
over the past century (1901-2015) with global tree ring data records from 2935
sites and associated plant trait data. Authors point out that this study based
on an analysis of long-term tree-ring data is the first one to report a
trade-off in their recent trends between gymnosperm resistance and resilience
to drought. According to the authors such decrease in drought resistance but
increase in their drought resilience may potentially indicate a recent
life-history strategy shift of gymnosperms in coping with changing climate and
drought stress regimes.
“Surprisingly, we found that the trade-off
between resistance and resilience for gymnosperms, previously reported only
spatially, also occurred at the temporal scale. In particular, drought
resilience significantly increased but resistance decreased for gymnosperms
between 1950-1969 and 1990-2009, indicating that previous models simulations
may have underestimated the impacts of drought on gymnosperm-dominated forests
under future climate change”, said the PhD student Xiangyi Li from the Sino-French Institute for
Earth System Science, College of Urban and Environmental Sciences, Peking
University, China.
“We suggest that the altered ecosystem carbon
cycle processes should be considered in the next generation of forest
simulators to improve their predictive capacity of future ecosystem functioning
and terrestrial carbon balance. The priority for further studies is to
establish a network for long-term and synchronized observations of plant growth
conditions and traits” said Prof. Josep Penuelas from CREAF-CSIC Barcelona.
Reference: Li, X., Piao, S.,
Wang, K., Wang, X., Wang, T., Ciais, P., Chen, A., Lian, X., Peng, S.,
Peñuelas, J. 2020. Temporal trade-off between gymnosperm resistance and
resilience increases forest sensitivity to extreme drought. Nature Ecology and Evolution.