Photosynthetic responses of 15 phytoplankton species to ammonium pulsing

Photosynthetic Responses of Legume Species to Leaf-Mass Consumption Injury

Several studies have addressed plant primary physiological responses (gas exchange responses) to insect herbivory. However, relatively few plant species have been examined. It is unknown whether responses to leaf-mass removal by insects vary among plant families and species. Within the legumes, only alfalfa,Medicago sativaL., and soybean,Glycine max (L.)Merrill, have been examined. The goal of ...

Photosynthetic Characteristics and Antioxidative Responses in Three Species of Crassulaceae Following Drought Stress

Photosynthetic characteristics and induction of crassulacean acid metabolism (CAM) by drought stress were investigated in Sedum album, Sedum stoloniferum and Rosularia elymaitica from Crassulaceae. Titratable acidity, malate content, phosphoenolpyruvate carboxylase (PEPC) activity and gas exchange parameters were determined in plants at the end and beginning of the photoperiod. Results showed t...

Leaf Photosynthetic Responses to Thinning

How Do Sinking Phytoplankton Species Manage to Persist? How Do Sinking Phytoplankton Species Manage to Persist?

Phytoplankton requires light for photosynthesis, but most phytoplankton species are heavier than water and sink. How can these sinking species persist? Here we show, by means of an advection-di usion-reaction equation of light-limited phytoplankton, that the answer lies in the turbulent motion of water that re-disperses phytoplankton over the vertical water column. More speci cally, we show tha...

Photosynthetic carboxylating enzymes in marine phytoplankton’

Measurements of ribulose-1,5-bisphosphate carboxylase (RUBPCase) and phosphoenolpyruvate carboxylase (PEPCase) in several phytoplankton cultures and natural phytoplankton populations showed a positive correlation of photosynthesis with RUBPCase activity but not with PEPCase activity. Observed ratios of RUBPCase:PEPCase were high in log phase cultures when photosynthesis was maximal and low in s...