Spatial and temporal variations in light-saturated photosynthetic capacity and needle nitrogen (N) content were investigated in one
8 m tall Japanese cedar (Cryptomeria japonica D. Don) canopy for a full year. The photosynthetic capacity and needle N content in various layers of the canopy were measured every month. Temporal variations in photosynthetic capacity and needle N content expressed on a projected-area basis (Parea, Narea) were similar. Furthermore, both Parea and Narea decreased with increasing depth from the top of the canopy on each sampling date. As a consequence, a significant correlation was observed between Narea and Parea. Temporal variations in photosynthetic capacity and needle N content expressed on a mass basis (Pmass, Nmass) were also similar. Pmass also decreased with increasing canopy depth. However, in contrast to Narea, there was only a slight decrease in Nmass with increasing canopy depth. Hence, the correlation between Nmass and Pmass was lower than the projected-area value. Because Narea was highly correlated with the needle mass per projected-area (NMA), the spatial variation in Narea (and therefore Parea) in the canopy is attributed to the variation in NMA, which decreases as the depth from the top of the canopy increases. Furthermore, the slope of the linear regression between Narea and NMA differed between sampling dates, indicating that the temporal variations in Narea (and therefore Parea) are strongly influenced by Nmass. For most of the sampling dates, a linear regression between Narea and Parea tends to converge into a single line segment. However, on several sampling dates, there was a pronounced decline in Parea below this line segment. This reduction in Parea, which does not accompany a reduction in Narea, seems to be attributable to stomatal limitations induced by the low soil temperature in winter and early spring. and H. Kobayashi, S. Inoue, K. Gyokusen
In South Bohemia, Czech Republic, 178 shrews, including 98 common shrews, Sorex araneus L., 70 pygmy shrews, Sorex minutus L., and 10 lesser white-toothed shrews, Crocidura suaveolens (Pallas), were examined for Soricimyxum fegati Prunescu, Prunescu, Pucek et Lom, 2007 infections, using squash preparations of unfixed tissues, histological sections and molecular methods. The infection was found in 51 (52%) S. araneus, 14 (20%) S. minutus and 1 (10%) C. suaveolens. The records of the latter two species extend host range of S. fegati. Lesions associated with S. fegati infections in the liver, the organ of specific localisation of the parasite, were found to be induced by proliferative stages migrating toward lumina of bile ducts. In other organs of these three host species, xenoma-like formations (XLFs) were found that severely injured blood vessels. XLFs contained presporogonic stages of S. fegati, whose species identity was evidenced using molecular methods.