Phenology and growth dynamics in Mediterranean evergreen oaks: Effects of environmental conditions and water relations

Pinto, Clara A.; Henriques, Manuel; Figueiredo, Joana; David, Jorge S.; Abreu, F. G.; Pereira, J. S.; Correia, Isabel; David, Teresa S.

doi:10.1016/j.foreco.2011.04.018

Cited by 60 publications

(36 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nonetheless, in addition to the abovementioned phenological heterogeneity within and between species and the influence of different environmental conditions [110][111][112], intra-annual variability is also an important factor [74,113]. Since the presented methodology uses insights that are obtained from near-surface observations of a single phenological cycle for determining optimal periods during the sequential phenological cycles, intra-annual variability could affect the robustness of the presented outcomes.…”

Section: Overhead Data Acquisition and Species Classificationmentioning

confidence: 99%

Optimizing the Timing of Unmanned Aerial Vehicle Image Acquisition for Applied Mapping of Woody Vegetation Species Using Feature Selection

et al. 2017

View full text Add to dashboard Cite

Abstract:Most recent studies relating to the classification of vegetation species on the individual level use cutting-edge sensors and follow a data-driven approach, aimed at maximizing classification accuracy within a relatively small allocated area of optimal conditions. However, this approach does not incorporate cost-benefit considerations or the ability of applying the chosen methodology for applied mapping over larger areas with higher natural heterogeneity. In this study, we present a phenology-based cost-effective approach for optimizing the number and timing of unmanned aerial vehicle (UAV) imagery acquisition, based on a priori near-surface observations. A ground-placed camera was used in order to generate annual time series of nine spectral indices and three color conversions (red, green and blue to hue, saturation and value) in four different East Mediterranean sites that represent different environmental conditions. After outliers' removal, the time series dataset represented 1852 individuals of 12 common vegetation species and annual herbaceous patches. A feature selection process was used for identifying the optimal dates for species classification in every site. The feature selection can be designed for various objectives, e.g., optimization of overall classification, discrimination between two species, or discrimination of one species from all others. In order to evaluate the a priori findings, a UAV was flown for acquiring five overhead multiband orthomosaics (five bands in the visible-near infrared range based on the five optimal dates identified in the feature selection of the near-surface time series of the previous year. An object-based classification methodology was used for the discrimination of 976 individuals of nine species and annual herbaceous patches in the UAV imagery, and resulted in an average overall accuracy of 85% and an average Kappa coefficient of 0.82. This cost-effective approach has high potential for detailed vegetation mapping, regarding the accessibility of UAV-produced time series, compared to hyper-spectral imagery with high spatial resolution which is more expensive and involves great difficulties in implementation over large areas.

show abstract

Section: Overhead Data Acquisition and Species Classificationmentioning

confidence: 99%

Optimizing the Timing of Unmanned Aerial Vehicle Image Acquisition for Applied Mapping of Woody Vegetation Species Using Feature Selection

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Whilst the holm oak is an evergreen tree species, it also has a budburst in spring. According to much research that has covered a wide area of the Mediterranean Basin, holm oak budburst occurs in the period from the end of March to the beginning of June, depending on the location [45][46][47][48][49]. In Croatia the budburst of holm oak occurs at the beginning of May (Lukić, personal observation).…”

Section: Discussionmentioning

confidence: 99%

Foliage maturity of Quercus ilex affects the larval development of a Croatian coastal population of Lymantria dispar (Lepidoptera: Erebidae)

et al. 2017

View full text Add to dashboard Cite

Gypsy moth (Lymantria dispar) is one of the most important forest pests in the world. Numerous previous studies focused only on different host tree species, but small number of them on foliage age. Since recent genetic analyses showed that there are significant differences between Croatian continental and coastal population we investigated coastal population since there was no previous research. For this research juvenile and mature foliage of Holm oak (Quercus ilex) was used. Larval development was investigated in two laboratory experiments. One experiment involved rearing trials consisting of 50 individual larvae per treatment while a parallel experiment investigated gregarious feeding conditions using 120 larvae in a rearing treatment. Larval mortality was lower and development time shorter for individuals reared on juvenile foliage. High pupation success in both the individual and group rearing experiment for larvae reared on juvenile foliage was also observed. To conclude, our results showed high mortality, poor larval development and low pupation success in larvae reared on mature foliage. This research is significant because in the aspect of ongoing climate changes there is a possibility that gypsy moth will move to the north and shift its distribution by expanding into new climatic area.

show abstract

“…Pinto et al (2011) used the example of Quercus ilex and Quercus suber to study the relationship between mean daily temperatures and budburst dates. Along with all the other factors, it was temperature that proved to be the most important.…”

Section: Temperature -Temperaturamentioning

confidence: 99%

“…We can assume that in heliophilic species and species of floodplain forest sites, precipitation and insolation are the principal activating factors of phenological manifestations, while in species of xerothermal sites this role is played mostly by temperature (Pinto et al 2011).…”

Section: Insolation -Insolacijamentioning

confidence: 99%

The impact of environmental drivers on narrow-leaved ash (Fraxinus angustifolia Vahl) budburst dates

Andrić

Kajba

2017

Šumar. list (Online)

View full text Add to dashboard Cite

Narrow-leaved ash (Fraxinus angustifolia Vahl) is a fast growing and light demanding forest tree species. In Croatia, the largest complexes of this species can be found along the Sava River. The main objective of research was to determine the influence of environmental drivers on budburst dates. Research was carried out in the clonal seed orchard of Nova Gradiška through four vegetation seasons (2012, 2014, 2015 and 2016). In total, 42 clones were involved in this study. The target phase of phenology monitoring was the phase with distinct budburst and partial segregation of bud scales. Three environmental drivers were selected (temperature, precipitation and insolation)

show abstract

Phenology and growth dynamics in Mediterranean evergreen oaks: Effects of environmental conditions and water relations

Cited by 60 publications

References 59 publications

Optimizing the Timing of Unmanned Aerial Vehicle Image Acquisition for Applied Mapping of Woody Vegetation Species Using Feature Selection

Optimizing the Timing of Unmanned Aerial Vehicle Image Acquisition for Applied Mapping of Woody Vegetation Species Using Feature Selection

Foliage maturity of Quercus ilex affects the larval development of a Croatian coastal population of Lymantria dispar (Lepidoptera: Erebidae)

The impact of environmental drivers on narrow-leaved ash (Fraxinus angustifolia Vahl) budburst dates

Contact Info

Product

Resources

About