Research Professor, Systems Ecology Research Group, San Diego State University, San Diego, Calif., 92182. Abstract: Photosynthesis and respiration rates were determined for chaparral shrubs as a function of temperature and/or light intensity. In mature stands at Echo Valley, Calif., net seasonal carbon assimilation by leaves ranges -2 from a dry weight equivalent of 673 g m -1 in -2 pure stands...

In this work, two Italian regions (Emilia Romagna, in Northern Italy, and Campania, in Southern Italy) are compared on the basis of an emergy evaluation carried out over the last 20 years. The regions show very different productive and institutional structures, which affect the overall performance. The Campania region is characterized by the presence of a high number of small productive units (...

Jatropha is the latest in a list of “miracle crops” that have been promoted in southern Africa for their perceived development benefits. This was based on promises of high yields, low water requirement, ability to grow on marginal land and lack of competition with food. In less than 10 years, tens of thousands of hectares were acquired for jatropha plantations and thousands of hectares were pla...

Longleaf pine (Pims puhrstrk Mill.) ecosystems once occupied over 36 million hectares in the southeastern United States’ lower coas ta l p la in . These f i re -dependent ecosys tems domina ted a w ide range of coastal plain sites, including dry uplands and low, wet flatlands. Today, less than 1.3 million hectares remain, but these ecosystems represent significant components of the Region’s cul...

High-precision land-cover-land-use GIS mapping was performed in four major townships in Maine’s Aroostook River Valley, using on-screen digitization and direct interpretation of very high spatial resolution satellite multispectral imagery (15–60 cm) and high spatial resolution LiDAR data (2 m) and the field mapping method. The project not only provides the first-ever high-precision land-use map...

Glyphosate-resistant (GR) crops have been adopted on a massive scale by North and South American farmers. Currently, about 80% of the 120 million hectares of the global genetically modified (GM) crops are GR crop varieties. However, the adoption of GR plants in China has not occurred at the same pace, owing to several factors including, among other things, labour markets and the residual effect...

Urbanization and urban development builds large amounts of impervious areas, stopping the infiltrating of rainfall into soil process and consequently, requiring of the construction of large stormwater treatment measures. A new tendency in storm water management endorses ‘source control’ whereby small distributed water sensitive urban design systems are built throughout the subdivision to allevi...

The terrestrial carbon sink, as of yet unidentified, represents 15-30% of annual global emissions of carbon from fossil fuels and industrial activities. Some of the missing carbon is sequestered in vegetation biomass and, under the Kyoto Protocol of the United Nations Framework Convention on Climate Change, industrialized nations can use certain forest biomass sinks to meet their greenhouse gas...

Every year forest fires cause severe financial losses in many countries of the world. Additionally, lives of humans as well as of countless animals are often lost. Due to global warming, the problem of wildfires is getting out of control; hence, the burning of thousands of hectares is obviously increasing. Most important, therefore, is the early detection of an emerging fire before its intensit...

Understanding nitrous oxide (N2O) fluxes from agricultural soils in semi-arid regions is required to better understand global terrestrial N2O losses. Nitrous oxide fluxes were measured from three rain-fed, cropped soils in a semi-arid region of south-western Australia on a sub-daily basis from 1995 to 2014 using automated chambers. Western Australia’s grain-belt includes 7 million hectares of a...