Anatomical functional traits and hydraulic vulnerability of trees in different water conditions in southern Amazonia.

PREMISE: Understanding tree species' responses to drought is critical for predicting the future of tropical forests, especially in regions where the climate is changing rapidly. METHODS: We compared anatomical and functional traits of the dominant tree species of two tropical forests in southern Amazonia, one on deep, well-drained soils (cerradão [CD]) and one in a riparian environment (gallery forest [GF]), to examine potential anatomical indicators of resistance or vulnerability to drought. RESULTS: Leaves of CD species generally had a thicker cuticle, upper epidermis, and mesophyll than those of GF species, traits that are indicative of adaptation to water deficit. In the GF, the theoretical hydraulic conductivity of the stems was significantly higher, indicating lower investment in drought resistance. The anatomical functional traits of CD species indicate a greater potential for surviving water restriction compared to the GF. Even so, it is possible that CD species could also be affected by extreme climate changes due to the more water-limited environment. CONCLUSIONS: In addition to the marked anatomical and functional differences between these phytophysiognomies, tree diversity within each is associated with a large range of hydraulic morphofunctional niches. Our results suggest the strong potential for floristic and functional compositional shifts under continued climate change, especially in the GF.

The service threshold.

New technologies are developed and refined every day, but the healthcare industry need not wait until they arrive to offer quality patient service. Moreover, a change in the service mindset of the Information Systems department can help an organization prepare to implement new technological advances that will directly improve quality of care.

It started with the cow path: working flatter, not faster.

Our first impulse was to pave the cow path, to computerize the way manual procedures were done. Then we tried to straighten out the cow path, to make those procedures more efficient. In this article, contributing editor Jim Wesley says we're still thinking this way, and argues that maybe we shouldn't be following the cow path model at all.

Comparing Three Methods for Counting Raw-Milk Pour Plates 1.

Six hundred Grade A raw milk samples were plated on Standard Methods agar and the pour-plate counts compared using three methods. Counts of each sample were determined after incubation at 26, 30 and 32 C for 72 h with an automatic colony counter (ACC). Quebec colony counter and hand tally (HT) and Quebec colony counter and electronic probe with digital register (DT). No significant differences were found between the counts obtained with the HT and the DT for any of the three incubation temperatures. The ACC counts were lower (P < .01) than the manual counts at each temperature. The ACC counts were .39, .35 and .31 log counts lower than the manual count at 26, 30 and 32 C, respectively. The ACC counts at 72 h were higher (P < .01) than the ACC counts at 48 h for all temperatures. The difference was about .41 log counts. The two manual counts were totally correlated, while the correlation between the ACC counts and the manual count; was 97. Regression equations were formulated for predicting the 72 h HT count from either the 48 or 72 h ACC count.