Fig 2 - uploaded by Antonio Gazol
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Hypothetical structural equation model established to study the direct and indirect infl uence of the different abiotic and biotic conditions on the distribution of adults and seedlings of Carex remota . Singleheaded arrows indicate direct causal relationships among variables; double-headed arrows indicate nonstudied relationships. Hypothesized positive relationships are indicated with solid lines; negative ones are indicated with dashed lines.
Source publication
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Premise of the study:
Plants respond to the prevailing conditions in the surrounding environment, but since they are dynamic systems this response may vary during their life. Thus, the identification of key aspects for the maintenance of plant populations requires the consideration of plant performance across environmental gradient...
Contexts in source publication
Context 1
... hypothetical model included direct and indirect relationships among the variables listed above ( Fig. 2 ). We hypothesize that the distribution of C. remota adult individuals can be directly and positively infl uenced by the soil moisture conditions, since this species strongly depends on water availability. ...
Context 2
... line with our expectations, C. remota seedlings were positively infl uenced by soil moisture, the distri- bution of adult individuals and light conditions. Similarly, seedling distribution was negatively infl uenced by leaf-litter coverage as we hypothesized in our hypothetical model ( Fig. 2 ). The proposed model accounted for 64% of the variation in C. remota adult distribution and 37% of the variation in the distribution of seedlings ( Fig. 5 ). ...
Citations
... For example, water availability and soil nutrient may be limiting for tree growth in the upland compare to low elevation positions (Lopez et al., 2021). Also, plants response to environmental variables may vary during their life time since they are dynamic systems (Uria-Diez et al., 2014). Tree of different sizes may respond differently to environmental stresses (Rathgeber et al., 2011). ...
Spatial species diversity and size inequality contribute to maintenance of tree species diversity in tropical forests. Coexistence of tree species requires interactions within and between spatial species and size diversity. However, elevation gradient has significant impact on growth and species interactions. Failure of most conservation efforts is due to inability to identify and maintain coexistence mechanisms existing in the forest. Understanding the contribution of elevation gradient to coexistence of tree species will improve conservation efforts and terrestrial carbon budgeting. Therefore, association between tree diversity and size inequality on elevation gradient of Elephant Camp Natural Forest was investigated. Eight (30m x 30m) plots were systematically demarcated on 1km line transects in each identified elevation (Hilltop and Valley-Bottom stands). Trees diameter-at-breast height (dbh) were enumerated and identified to species level. Tree dbh was measured and density estimated. Tree species diversity (Shannon-Weiner, Simpson and Margalef indices) and size inequality (Gini coefficient, skewness and Coefficient of variation) were computed. Stem volume and biomass were computed and converted to biomass carbon. Data collected were analysed using descriptive, correlation analysis and principal component analysis. Tree density varied from 435/ha to 767/ha. There was positive correlation between Skewness and Gini coefficient in Hilltop stand and negative correlation between Skewness and Simpson index in Valley-Bottom stand. The measures of tree size inequality and species diversity were strongly associated with each other in Valley-Bottom stand and not in Hilltop stand. Structural diversity and species diversity determined the competitive interaction among tree communities in Hilltop and Valley-Bottom stands, respectively.
