The long-term fitness of individuals is examined in complex and temporally dynamic ecosystems. We call this multigeneration fitness measure "future fitness". Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) is a polyphagous insect that feeds on many wild and cultivated hosts. While four generations of H. zea occur during the cropping season in the U.S. Mid Southern agroecosysem, the latter two...

A change in climate is known to affect seasonal timing (phenology) of the life stages of poikilothermic organisms whose development depends on temperature. Less understood is the potential for even greater disruption to the life cycle when a phenology shift exposes photoperiod-sensitive life stages to new day lengths. We present a conceptual framework and model to investigate the ways that phot...

P art of the diversity of a forest is the variety of agents that can kill trees. These agents differ in the nature, magnitude, and patterns of their impacts on forest resources. Diseases, insect pests, and other small-scale disturbances are commonly assessed on the basis of their impacts on timber production. Tree mortality usually means reduced volume of living stems. Consequently, forest path...

The circum-polar boreal forest has played an important role in the wealth of northern nations since the 15th century. Its natural resources spurred strategic geopolitical developments beginning in the 16th century but intense development of the boreal forest is largely limited to the 20th century. Insects cause considerable loss of wood that has an adverse effect on the balance of carbon seques...

the study examined prospects of selected forest fruits and vegetables in enugu north agricultural zone of enugu state, nigeria. structured interview schedule and focus group discussion were used to collect data from a sample of one hundred and twenty (120) respondents. data were analyzed using matrix rank ordering, percentage, mean scores and standard deviation. results of the study identified ...

Monocropped plantations are unique to India and a handful of countries throughout the globe. Essentially, the FOREST approach of growing coffee along with in India has enabled the plantation to fight many outbreaks of pests and diseases. Mono cropped Plantations are under constant threat of pest and disease incidence because it favours the build up of pest population. To cope with these problem...

We used twelve Landsat scenes from the 1980s–2009 and regional 2000–2009 MODIS data to examine the long-term trend in the normalized difference vegetation index (NDVI) within unburned areas of the Alaskan boreal forest. Our analysis shows that there has been a declining trend in NDVI in this region, with the strongest ―browning trend‖ occurring in eastern Alaska where the climate during the gro...