The North Atlantic zone of Costa Rica is an alluvial plain, whose fairly good soils and warm, extremely wet climate generate serious weed problems in cultivated crops and pastureland. Basic foods - corn, beans, rice and yuca - are important small farm crops. New land is still being opened for...
The Federal Water Pollution Control Act Amendments of 1972
prohibits the discharge of seafood processing solid wastes into
navigable waters after July 1, 1977. Oregon shrimp and crab processors
must use other methods of disposal for the 15 to 30 million
pounds of solid waste generated annually. The application of...
Charge transport in a semiconductor structure with heterojunction is described by a multiscale partial differential equation model. This model can be used, e.g., for the design of more efficient solar cells. Phenomena at the heterojunction must be resolved at the angstrom scale while the size of the device is that...
Grain yield and grain protein are often negatively associated in
wheat. When yield increases and grain protein decreases, there can be
an adverse effect on the milling and baking quality if the desired end
product is bread flour. It has been suggested that this inverse
association is the result of...
Twenty-one rice cultivars were evaluated to determine the difference between populations of Sogatodes oryzicola (Muir) (Homoptera: Delphacidae) in Costa Rica and Colombia, Survival, mortality and population development of S. oryzicola on five selected cultivars was used to determine levels of plant resistance. The importance and potential of the parasitoid-predator Haplogonatopus...
Mycorrhizae are important for plant growth, particularly in nutritionally poor soils. Vesicular-arbuscular mycorrhizae (VAM) are the primary form of mycorrhizae found in tropical plants, and their persistence in the soil as colonizing fungal propagules following deforestation cannot be directly
measured. Utilizing the "most probable number" (MPN) method for estimating infective...
Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, may also negatively affect biodiversity for those species that exhibit behavioral responses to changes in habitat configuration. Such behavioral changes include...
