Early Response to Liberation and Climatic Seasonality of Selected Timber Species in a Tropical Mountain Forest of Southern Ecuador

Research Highlights: The study determined that selective thinning causes different responses, the initial size of the tree released is an influential factor in the growth of species. The temporality of climate and physiological conditions of each species are influential in the growth. It is evident that the defoliation of certain species is an important factor that limits the growth of the species causing thinning to have a negative response. Background and Objectives: The objective is to analyze the behavior of nine timber species, respective to diametric growth after their liberation. This research aims to answer the following questions: (i) How do the selected tree species react to the liberation? (ii) Can the productivity of the trees (diametric growth) be enhanced by liberation? (iii) Are there other factors that influence the diametric growth of the released trees? Materials and Methods: The study was executed in the “Reserva Biológica San Francisco” were 488 trees were monitored, including nine timber species. Therefore, 197 trees were released (removal of competitors) and 251 trees served as reference. To check whether the initial DBH or other factors, like the selective thinning or climate conditions, determine the diameter growth a linear mixed model GLMM was applied. To adjust the linear mixed model a one-way Anova test was executed. Results: Timber species responded differently to the thinning in comparing to reference trees. Therefore, the species analyzed were separated into three groups (positive, negative, and no response to liberation). Conclusions: Liberation potentiates the growth of certain timber species that do not defoliate and considered semi-tolerant to shade. Precipitation and temperature affect all species, but in the defoliate species, it would not be convenient to release them or at least the evidence of these first three years does not show clear differences with control trees. Increase in trees released are higher in trees of the first two diametric classes in all species, this means that larger trees (i.e., older) release does not affect them in a positive way so release should occur in the youngest trees.

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Early Growth Response of Nine Timber Species to Release in a Tropical Mountain Forest of Southern Ecuador

Forests ◽

10.3390/f10030254 ◽

2019 ◽

Vol 10 (3) ◽

pp. 254 ◽

Cited By ~ 6

Author(s):

Omar Cabrera ◽

Andreas Fries ◽

Patrick Hildebrandt ◽

Sven Günter ◽

Reinhard Mosandl

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Growth Habit ◽

R Package ◽

Mountain Forest ◽

Timber Species ◽

Older Individuals ◽

Humid Climate ◽

Climate Conditions ◽

Shade Tolerant Species

Research Highlights: This study determined that treatment “release from competitors” causes different reactions in selected timber species respective to diametrical growth, in which the initial size of the tree (diametric class) is important. Also, the growth habit and phenological traits (defoliation) of the species must be considered, which may have an influence on growth after release. Background and Objectives: The objective of the study was to analyze the diametric growth of nine timber species after their release to answer the following questions: (i) Can the diametric growth of the selected timber species be increased by release? (ii) Does the release cause different responses among the tree species? (iii) Are other factors important, such as the initial diameter at breast height (DBH) or the general climate conditions? Materials and Methods: Four-hundred and eighty-eight trees belonging to nine timber species were selected and monitored over a three-year period. Release was applied to 197 trees, whereas 251 trees served as control trees to evaluate the response of diametrical growth. To determine the response of the trees, a linear mixed model (GLMM, R package: LMER4) was used, which was adjusted by a one-way ANOVA test. Results: All species showed a similar annual cycle respective to diametric increases, which is due to the per-humid climate in the area. Precipitation is secondary for the diametric growth because sufficient rainfall occurs throughout year. What is more important, however, are variations in temperature. However, the species responded differently to release. This is because the initial DBH and growth habit are more important factors. Therefore, the species could be classified into three specific groups: Positive, negative and no response to release. Conclusions: Species which prefer open sites responded positively to release, while shade tolerant species and species with pronounced phenological traits responded negatively. The initial DBH was also an important factor for diametric increases. This is because trees of class I (20 cm to 30 cm DBH) responded positively to the treatment, whereas for bigger or older individuals, the differences decreased or became negative.

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Predicting bycatch hotspots based on suitable habitat derived from fishery-independent data

Marine Ecology Progress Series ◽

10.3354/meps13302 ◽

2020 ◽

Vol 641 ◽

pp. 159-175

Author(s):

J Runnebaum ◽

KR Tanaka ◽

L Guan ◽

J Cao ◽

L O’Brien ◽

...

Keyword(s):

Habitat Suitability ◽

Mixed Model ◽

Linear Mixed Model ◽

Gulf Of Maine ◽

Homarus Americanus ◽

Management Tool ◽

American Lobster ◽

Suitable Habitat ◽

Climate Conditions ◽

Suitability Index

Bycatch remains a global problem in managing sustainable fisheries. A critical aspect of management is understanding the timing and spatial extent of bycatch. Fisheries management often relies on observed bycatch data, which are not always available due to a lack of reporting or observer coverage. Alternatively, analyzing the overlap in suitable habitat for the target and non-target species can provide a spatial management tool to understand where bycatch interactions are likely to occur. Potential bycatch hotspots based on suitable habitat were predicted for cusk Brosme brosme incidentally caught in the Gulf of Maine American lobster Homarus americanus fishery. Data from multiple fisheries-independent surveys were combined in a delta-generalized linear mixed model to generate spatially explicit density estimates for use in an independent habitat suitability index. The habitat suitability indices for American lobster and cusk were then compared to predict potential bycatch hotspot locations. Suitable habitat for American lobster has increased between 1980 and 2013 while suitable habitat for cusk decreased throughout most of the Gulf of Maine, except for Georges Basin and the Great South Channel. The proportion of overlap in suitable habitat varied interannually but decreased slightly in the spring and remained relatively stable in the fall over the time series. As Gulf of Maine temperatures continue to increase, the interactions between American lobster and cusk are predicted to decline as cusk habitat continues to constrict. This framework can contribute to fisheries managers’ understanding of changes in habitat overlap as climate conditions continue to change and alter where bycatch interactions could occur.

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Projecting land-use and land-cover changes in a tropical mountain forest of Southern Ecuador

Journal of Land Use Science ◽

10.1080/1747423x.2012.736197 ◽

2012 ◽

Vol 9 (1) ◽

pp. 131-131

Author(s):

Boris Thies ◽

Hanna Meyer ◽

Thomas Nauss ◽

Jörg Bendix

Keyword(s):

Land Use ◽

Land Cover ◽

Mountain Forest ◽

Land Cover Changes ◽

Tropical Mountain ◽

Southern Ecuador

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Estimation of Above Ground Biomass in a Tropical Mountain Forest in Southern Ecuador Using Airborne LiDAR Data

Remote Sensing ◽

10.3390/rs10050660 ◽

2018 ◽

Vol 10 (5) ◽

pp. 660 ◽

Cited By ~ 11

Author(s):

Víctor González-Jaramillo ◽

Andreas Fries ◽

Jörg Zeilinger ◽

Jürgen Homeier ◽

Jhoana Paladines-Benitez ◽

...

Keyword(s):

Airborne Lidar ◽

Mountain Forest ◽

Lidar Data ◽

Above Ground Biomass ◽

Ground Biomass ◽

Tropical Mountain ◽

Southern Ecuador ◽

Airborne Lidar Data

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Projecting land-use and land-cover changes in a tropical mountain forest of Southern Ecuador

Journal of Land Use Science ◽

10.1080/1747423x.2012.718378 ◽

2012 ◽

Vol 9 (1) ◽

pp. 1-33 ◽

Cited By ~ 21

Author(s):

Boris Thies ◽

Hanna Meyer ◽

Thomas Nauss ◽

Jörg Bendix

Keyword(s):

Land Use ◽

Land Cover ◽

Mountain Forest ◽

Land Cover Changes ◽

Tropical Mountain ◽

Southern Ecuador

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Prediction of Friction Degradation in Highways with Linear Mixed Models

Coatings ◽

10.3390/coatings11020187 ◽

2021 ◽

Vol 11 (2) ◽

pp. 187

Author(s):

Adriana Santos ◽

Elisabete F. Freitas ◽

Susana Faria ◽

Joel R. M. Oliveira ◽

Ana Maria A. C. Rocha

Keyword(s):

Mixed Models ◽

Mixed Model ◽

Linear Mixed Model ◽

Linear Mixed Models ◽

Pavement Management ◽

Climate Conditions ◽

Pavement Management Systems ◽

Geometrical Features ◽

Highway Network ◽

Network Manager

The development of a linear mixed model to describe the degradation of friction on flexible road pavements to be included in pavement management systems is the aim of this study. It also aims at showing that, at the network level, factors such as temperature, rainfall, hypsometry, type of layer, and geometric alignment features may influence the degradation of friction throughout time. A dataset from six districts of Portugal with 7204 sections was made available by the Ascendi Concession highway network. Linear mixed models with random effects in the intercept were developed for the two-level and three-level datasets involving time, section and district. While the three-level models are region-specific, the two-level models offer the possibility to be adopted to other areas. For both levels, two approaches were made: One integrating into the model only the variables inherent to traffic and climate conditions and the other including also the factors intrinsic to the highway characteristics. The prediction accuracy of the model was improved when the variables hypsometry, geometrical features, and type of layer were considered. Therefore, accurate predictions for friction evolution throughout time are available to assist the network manager to optimize the overall level of road safety.

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Effect of seaweed extract application on wine grape yield in Australia

Journal of Applied Phycology ◽

10.1007/s10811-021-02423-1 ◽

2021 ◽

Author(s):

Tony Arioli ◽

Scott W. Mattner ◽

Graham Hepworth ◽

David McClintock ◽

Rachael McClinock

Keyword(s):

Mixed Model ◽

Field Experiments ◽

Linear Mixed Model ◽

Climate Extremes ◽

Seaweed Extract ◽

Wine Grape ◽

Climate Conditions ◽

Mixed Model Approach ◽

Budget Analysis ◽

Grape Yield

AbstractSeaweed extracts are agricultural biostimulants that have been shown to increase the productivity of many crops. The aim of this study was to determine the effect of a seaweed extract from the brown algae Durvillaea potatorum and Ascophyllum nodosum as a soil treatment on the yield of wine grapes grown in Australian production and climate conditions. This study used a series of seven field experiments (2012–2017), across five locations, in three Australian states and four cultivars, and analysed data using a linear mixed model approach. The analysis revealed that recurring soil applications of the seaweed extract significantly increased wine grape yield by an average of 14.7% across multiple growing years that experienced climate extremes. Partial budget analysis showed that the use of the seaweed extract increased profits depending on the grape cultivar. This study is the most extensive investigation of its type in Australian viticulture to understand the effect of a soil-applied seaweed extract on wine grape production.

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Functional Diversity Changes after Selective Thinning in a Tropical Mountain Forest in Southern Ecuador

Diversity ◽

10.3390/d12060256 ◽

2020 ◽

Vol 12 (6) ◽

pp. 256

Author(s):

Omar Cabrera ◽

Patrick Hildebrandt ◽

Bernd Stimm ◽

Sven Günter ◽

Andreas Fries ◽

...

Keyword(s):

Functional Diversity ◽

Functional Divergence ◽

Permanent Plots ◽

Mountain Forest ◽

Timber Species ◽

Mountain Forests ◽

Tropical Mountain ◽

Silvicultural Treatment ◽

Functional Richness ◽

The Impact

Background: The impact of selective thinning on forest diversity has been extensively studied in temperate and boreal regions. However, in the tropics, knowledge is still poor regarding the impacts of this silvicultural treatment on functional diversity, especially in tropical mountain forests, which are considered to be highly biodiverse ecosystems and also endangered by human activities. By evaluating the changes on functional diversity by using different indicators, hypothesizing that selective thinning significantly affects (directly or indirectly) tropical mountain forests, this work promotes sustainable ecosystem use. Methods: A total of 52 permanent plots of 2500 m2 each were installed in a primary mountain forest in the San Francisco Biological Reserve to assess the impact of this silvicultural treatment. Selective thinning can be defined as a controlled process, in which trees that compete with ecologically and/or valuable timber species are progressively removed to stimulate the development of profitable ones, called potential crop trees (PCT). In doing so, the best specimens remain in the forest stand until their final harvest. After PCT selection, 30 plots were chosen for the intervention, while 22 plots served as control plots. The thinning intensity fluctuated between 4 and 56 trees ha−1 (average 18.8 ± 12.1 stems ha−1). Functional Diversity (FD) indices, including the community weighted mean (CWM), were determined based on six traits using the FD package implemented in R software. The difference between initial and final conditions of functional richness (FRic), functional divergence (FDiv), functional evenness (FEve), functional dispersion (FDis), and Rao quadratic entropy (RaoQ) was modeled using linear mixed models (LMM). As fixed factors, we used all the predictors inherent to structural and ecological forest conditions before and after the selective thinning and as a random variable, we used the membership to nested sampling units. Results: Functional Richness (FRic) showed significant changes after selective thinning, the other indexes (FEve, FDis, FDiv, RaoQ) were only influenced by predictors related to ecological conditions and characteristics of the community.

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