Impacts of plant invasions are largely scale-dependent and responses to the same exotic species may vary among communities. Since impacts caused by individual trees could anticipate consequences of a closed canopy of an invader, we studied the response of Galápagos native plants to quinine (Cinchona pubescens) trees in two vegetation zones. Quinine has invaded >11,000 ha of Santa Cruz Island, i...

Reflectance of red (656-705 nm) and infrared (776-826 nm) solar radiation and standing crop biomass were measured in three salt marsh communities at intervals of approximately 2 weeks between February and August 1974. Red reflectance declined at the onset of greening in each community and was correlated with standing crop of green biomass. Infrared reflectance increased substantially in the shr...

[1] To increase our understanding of carbon (C) cycling and storage in soils, we used C to trace C from roots into four soil organic matter (SOM) fractions and the movement of soil microbes in arctic wet sedge and tussock tundra. For both tundra types, the proportion of C activity in the soil was 6% of the total C-CO2 taken up by plants at each of the four harvests conducted 1, 7, 21, and 68 da...

Arctic landscapes are characterized by a diversity of ecosystems, which differ in plant species composition, litter biochemistry, and biogeochemical cycling rates. Tundra ecosystems differing in plant composition should contain compositionally and functionally distinct microbial communities that differentially transform dissolved organic matter as it moves downslope from dry, upland to wet, low...

During December/January 1996/97 typical summer syndrome (hyperthermia and a 30% drop in milk yield) occurred in succession in two Holstein dairy herds (n=240 and n=150 milking cows, respectively) on the South African Highveld. These farms are situated in the midst of the prime maize and dairy farming areas of South Africa where this condition had never been diagnosed before. The individual comp...

LOUISE WOOTTON (Department of Biology, Georgian Court University, 900 Lakewood Avenue, Lakewood, NJ 08701). First report of Carex macrocephala in eastern North America with notes on its co-occurrence with Carex kobomugi in New Jersey. Torrey Bot. Soc. 134: 126–134. 2007.—The discovery of three populations of the large-headed sedge, Carex macrocephala, in New Jersey described in this paper, repr...