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A non-destructive continuous monitoring technology was developed for documenting diurnal changes in branch weight using resistance strain gauges. The capacity of rainfall interception by the canopy can be directly measured by attaching strain gauges to the branch. The amount of water loaded in tree reaches a maximum in the early morning, and a minimum in the afternoon. Thus, the branch is the heaviest in the early morning, and the lightest in the afternoon. Differences between the weight in the morning and in the afternoon can represent as the daily change in water loading of the branch. The branch can be considered as an elastic cantilever in response to the changes in weight of water carried by the branchlets and leaves, and the changes in strain are caused by the change in the bending stress of branch. Thus, the branch increases its weight when rainfall interception occurs, that also changes the stress of branch. The technique reported in this paper will provide an effective approach to investigating biological biometrics.

Luanta-fir (Cunninghamia konishii), an endemic to Taiwan, is an outcrossing, long-lived conifer. Populations of C. konishii are generally fragmented due to a once high intensity of timber exploitation. C. konishii and Cunninghamia lanceolata are two sibling taxa constituting derivative-progenitor species relationship. The amount of genetic variations within and between 11 and 10 populations of C. konishii and C. lanceolata, respectively, were assessed using amplified fragment length polymorphism (AFLP) markers in this report. Three AFLP primer pairs generated a total of 357 and 226 markers for C. konishii and C. lanceolata samples, of which 56.1 and 65.3% are polymorphic, respectively. Analysis of molecular variance indicates a 4.78% variation between C. konishii and C. lanceolata. A relatively high value of genetic variation (24.60%) was apportioned between the populations of C. konishii. In contrast, a lower divergence value (12.21%) between populations was found for C. lanceolata. The population with the highest genetic diversity was found in Nantou County, which concurred with the results of many other tree species investigated in Taiwan. The estimates of the number of migrants between populations (Nm), obtained from population pair-wise ΦST, suggest that gene flow in C. konishii is efficient in some adjacent populations but is restricted in the rest. Individual UPGMA tree, generated based on AFLP markers, suggests six evolutionary lineages for C. konishii. All evolutionary lineages of C. konishii were derived from C. lanceolata. In conclusion, the migration patterns of Cunninghamia from mainland China may have been established following multiple sources, migrant-pools, long-distance dispersal events, and via different directions.