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Stand competition determines how different tree species will cope with a warming climate.

Fernández-de-Uña L, Cañellas I, Gea-Izquierdo G - PLoS ONE (2015)

Bottom Line: Growth always decreased exponentially with increasing competition, which explained more growth variability than climate in Q. faginea and P. sylvestris.The effect of precipitation was asymptotic in all cases, while the relationship between growth and temperature reached an optimum after which growth declined with warmer temperatures.However, P. sylvestris growth would decline regardless of the competition level, whereas this decrease would be offset by reduced competition in Q. faginea.

View Article: PubMed Central - PubMed

Affiliation: Forest Research Centre, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CIFOR), Madrid, Spain.

ABSTRACT
Plant-plant interactions influence how forests cope with climate and contribute to modulate species response to future climate scenarios. We analysed the functional relationships between growth, climate and competition for Pinus sylvestris, Quercus pyrenaica and Quercus faginea to investigate how stand competition modifies forest sensitivity to climate and simulated how annual growth rates of these species with different drought tolerance would change throughout the 21st century. Dendroecological data from stands subjected to thinning were modelled using a novel multiplicative nonlinear approach to overcome biases related to the general assumption of a linear relationship between covariates and to better mimic the biological relationships involved. Growth always decreased exponentially with increasing competition, which explained more growth variability than climate in Q. faginea and P. sylvestris. The effect of precipitation was asymptotic in all cases, while the relationship between growth and temperature reached an optimum after which growth declined with warmer temperatures. Our growth projections indicate that the less drought-tolerant P. sylvestris would be more negatively affected by climate change than the studied sub-Mediterranean oaks. Q. faginea and P. sylvestris mean growth would decrease under all the climate change scenarios assessed. However, P. sylvestris growth would decline regardless of the competition level, whereas this decrease would be offset by reduced competition in Q. faginea. Conversely, Q. pyrenaica growth would remain similar to current rates, except for the warmest scenario. Our models shed light on the nature of the species-specific interaction between climate and competition and yield important implications for management. Assuming that individual growth is directly related to tree performance, trees under low competition would better withstand the warmer conditions predicted under climate change scenarios but in a variable manner depending on the species. Thinning following an exponential rule may be desirable to ensure long-term conservation of high-density Mediterranean woodlands, particularly in drought-limited sites.

No MeSH data available.


Related in: MedlinePlus

Map of the Iberian Peninsula with the location of the study sites.BP: Barriopedro (Q. faginea); NA: Navasfrías (Q. pyrenaica); RA: Rascafría (Q. pyrenaica); DU: Duruelo (P. sylvestris); NE: Neila (P. sylvestris).
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pone.0122255.g001: Map of the Iberian Peninsula with the location of the study sites.BP: Barriopedro (Q. faginea); NA: Navasfrías (Q. pyrenaica); RA: Rascafría (Q. pyrenaica); DU: Duruelo (P. sylvestris); NE: Neila (P. sylvestris).

Mentions: We selected different locations for each of the study species within the INIA network of long-term thinning experimental plots: Barriopedro (BP) for Q. faginea (QUFG); Navasfrías (NA) and Rascafría (RA) for Q. pyrenaica (QUPY); and Duruelo (DU) and Neila (NE) for P. sylvestris (PISY; Fig 1). The site characteristics are detailed in Table 1. All plots were located in even-aged, monospecific, naturally regenerated stands representative of the dominant woodlands currently found within the region. Quercus spp. stands were traditionally managed as coppice forests. Multiple stems per tree were common at the Q. faginea site, whereas the trees at the Q. pyrenaica sites generally had only one stem. At each site, 770-1600-m2 plots were marked and randomly either assigned a thinning treatment (light thinning—15–25% plot basal area [BA] reduction—, moderate thinning—35% BA reduction—, or heavy thinning—up to 50% BA reduction) or left unaltered for control purposes, with at least one repetition per treatment. Thinning from below (i.e., thinning that removes the smallest trees in the stand) was performed the year of plot establishment (Table 1) and in approximately 10-year rotation periods. Diameter at breast height (DBH) of all trees was measured in all plots every 4–10 years since plot establishment. Plots were established and are periodically thinned and inventoried with the authorization of the regional governments of Castilla-La Mancha (BP), Castilla y León (NA, DU and NE) and Madrid (RA). No specific permits were required for sampling at these sites, because the study did not involve endangered or protected species nor did it have any potential long-term effects on the sampled trees.


Stand competition determines how different tree species will cope with a warming climate.

Fernández-de-Uña L, Cañellas I, Gea-Izquierdo G - PLoS ONE (2015)

Map of the Iberian Peninsula with the location of the study sites.BP: Barriopedro (Q. faginea); NA: Navasfrías (Q. pyrenaica); RA: Rascafría (Q. pyrenaica); DU: Duruelo (P. sylvestris); NE: Neila (P. sylvestris).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4380403&req=5

pone.0122255.g001: Map of the Iberian Peninsula with the location of the study sites.BP: Barriopedro (Q. faginea); NA: Navasfrías (Q. pyrenaica); RA: Rascafría (Q. pyrenaica); DU: Duruelo (P. sylvestris); NE: Neila (P. sylvestris).
Mentions: We selected different locations for each of the study species within the INIA network of long-term thinning experimental plots: Barriopedro (BP) for Q. faginea (QUFG); Navasfrías (NA) and Rascafría (RA) for Q. pyrenaica (QUPY); and Duruelo (DU) and Neila (NE) for P. sylvestris (PISY; Fig 1). The site characteristics are detailed in Table 1. All plots were located in even-aged, monospecific, naturally regenerated stands representative of the dominant woodlands currently found within the region. Quercus spp. stands were traditionally managed as coppice forests. Multiple stems per tree were common at the Q. faginea site, whereas the trees at the Q. pyrenaica sites generally had only one stem. At each site, 770-1600-m2 plots were marked and randomly either assigned a thinning treatment (light thinning—15–25% plot basal area [BA] reduction—, moderate thinning—35% BA reduction—, or heavy thinning—up to 50% BA reduction) or left unaltered for control purposes, with at least one repetition per treatment. Thinning from below (i.e., thinning that removes the smallest trees in the stand) was performed the year of plot establishment (Table 1) and in approximately 10-year rotation periods. Diameter at breast height (DBH) of all trees was measured in all plots every 4–10 years since plot establishment. Plots were established and are periodically thinned and inventoried with the authorization of the regional governments of Castilla-La Mancha (BP), Castilla y León (NA, DU and NE) and Madrid (RA). No specific permits were required for sampling at these sites, because the study did not involve endangered or protected species nor did it have any potential long-term effects on the sampled trees.

Bottom Line: Growth always decreased exponentially with increasing competition, which explained more growth variability than climate in Q. faginea and P. sylvestris.The effect of precipitation was asymptotic in all cases, while the relationship between growth and temperature reached an optimum after which growth declined with warmer temperatures.However, P. sylvestris growth would decline regardless of the competition level, whereas this decrease would be offset by reduced competition in Q. faginea.

View Article: PubMed Central - PubMed

Affiliation: Forest Research Centre, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CIFOR), Madrid, Spain.

ABSTRACT
Plant-plant interactions influence how forests cope with climate and contribute to modulate species response to future climate scenarios. We analysed the functional relationships between growth, climate and competition for Pinus sylvestris, Quercus pyrenaica and Quercus faginea to investigate how stand competition modifies forest sensitivity to climate and simulated how annual growth rates of these species with different drought tolerance would change throughout the 21st century. Dendroecological data from stands subjected to thinning were modelled using a novel multiplicative nonlinear approach to overcome biases related to the general assumption of a linear relationship between covariates and to better mimic the biological relationships involved. Growth always decreased exponentially with increasing competition, which explained more growth variability than climate in Q. faginea and P. sylvestris. The effect of precipitation was asymptotic in all cases, while the relationship between growth and temperature reached an optimum after which growth declined with warmer temperatures. Our growth projections indicate that the less drought-tolerant P. sylvestris would be more negatively affected by climate change than the studied sub-Mediterranean oaks. Q. faginea and P. sylvestris mean growth would decrease under all the climate change scenarios assessed. However, P. sylvestris growth would decline regardless of the competition level, whereas this decrease would be offset by reduced competition in Q. faginea. Conversely, Q. pyrenaica growth would remain similar to current rates, except for the warmest scenario. Our models shed light on the nature of the species-specific interaction between climate and competition and yield important implications for management. Assuming that individual growth is directly related to tree performance, trees under low competition would better withstand the warmer conditions predicted under climate change scenarios but in a variable manner depending on the species. Thinning following an exponential rule may be desirable to ensure long-term conservation of high-density Mediterranean woodlands, particularly in drought-limited sites.

No MeSH data available.


Related in: MedlinePlus