Abstract The world’s most valuable resource is water in addition to being essential life, freshwater also used many other processes, including those that involve agriculture, industry, and human consumption due interference with its quality, it continues be a limited resource. Fresh potable supply, particularly urban areas, has been severely impacted by population increase, urbanization, consum...

Premise of research. Accumulating data from phylogenetic analyses living taxa and paleobotany (pollen, leaves, floral structures) has greatly improved our understanding the Cretaceous rise to dominance angiosperms. Relatives near-basal family Chloranthaceae were conspicuous in Early Cretaceous. These include female flowers adhering pollen (Asteropollis) that resemble those genus Hedyosmum, but ...

The reconstruction of evolution. Heredity 18:553. (Abstr.) FARMS, J. S. 1986. On the boundaries of phylogenetic systematics. Cladistics 2:14r-27. FARRIS, J. SV AND A. G. KLUGE. 1986. Synapomorphy, parsimony, and explanatory power. Taxon 35:298306. FARRIS, J. S., A. G. KLUGE, AND M. J. ECKARDT. 1970. A numerical approach to phylogenetic systematics. Syst. Zool. 19:172-179. FELSENSTEIN, J. 1982. ...

In vascular plants there are at least eight ways to develop polymerous whorls, i.e., whorls with four or more leaves. Six ways are presented and compared with literature to estimate organ identity (morphological significance) of the leaflike whorl members. New shoots (also seedlings) may start with dimerous or trimerous whorls. Then leaf number per whorl rises as follows: (1) Many taxa add more...

Abstract In Central Yakutia (Siberia) livelihoods of local communities depend on alaas (thermokarst depression) landscapes and the lakes within. Development dynamics these are closely connected to climate change, permafrost thawing, catchment conditions, land use. To reconstruct lake development throughout Holocene we analyze sedimentary ancient DNA (sedaDNA) biogeochemistry from a sediment cor...

2/3 of the reservoir surface area was approximately covered with dense populations of Myriophyllum, Ceratophyllum and Potamogeton species. The headwaters of the reservoir were considered as hard water and had both carbonatic and non-carbonatic hardness. When they were exposed to lentic condition of the reservoir and its intensive photosynthetic activities of macrophyte communities, the bicarbon...

Few data are available on net productivity rates in Laurentian Great Lakes wetland communities. We used several methods (Licor photosynthesis system and various radiotracer methods) to estimate midsummer carbon photoassimilation rates among important phytoplanktonic and aquatic macrophyte assemblages in Old Woman Creek National Estuarine Research Reserve (OWC) on Lake Erie near Huron, OH, durin...

Dating analyses based on molecular data imply that crown angiosperms existed in the Triassic, long before their undisputed appearance in the fossil record in the Early Cretaceous. Following a re-analysis of the age of angiosperms using updated sequences and fossil calibrations, we use a series of simulations to explore the possibility that the older age estimates are a consequence of (i) major ...

The nutria or coypu (Myocastor coypus) is a rodent native to South America that has been introduced almost worldwide since the early 1900’s, originally with the intent of fur farming in many cases. The nutria is a large (over 6 kg), semi-aquatic rodent with a voracious appetite and high reproductive potential. Nutria became established in the Louisiana wetlands in the 1930’s. The habitat proved...