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The movement of soil and sediment in Earth's atmosphere: microbiology and ecosystem health
No abstract available.
Considerations in the reintroduction of native mammalian species to restore natural ecosystems
No abstract available.
Bottomland hardwood forest ecosystem hydrology and the influence of human activities
No abstract available.
Fire in Mediterranean climate ecosystems-A comparative overview
Four regions of the world share a similar climate and structurally similar plant communities with the Mediterranean Basin. These five areas, known collectively as "mediterranean-type climate (MTC) regions", are dominated by evergreen sclerophyllous-leaved shrublands, semi-deciduous scrub, and woodlands, all of which are prone to widespread crown fires. Summer droughts produce an annual fire hazard that contributes to a highly predictable fire regime. Fire has been an important factor driving the convergence of these systems and is reflected in plant traits such as lignotubers in resprouting shrubs and delayed reproduction that restricts recruitment to a postfire pulse of seedlings. On fertile soils where postfire resprouting is very rapid, opportunities for postfire seedling recruitment are limited and thus these woody taxa have not opted for delaying reproduction. Such fire-independent recruitment is widespread in the floras of MTC regions of the Mediterranean Basin and California and postfire seeding tends to dominate at the more arid end of the gradient. Due to very different geological histories in South Africa and Western Australia, substrates are nutrient poor and thus postfire resprouters do not pose a similar competitive challenge to seedlings and thus postfire seeding is very widespread in these floras. Although circumstantial evidence suggests that the MTC region of Chile had fire-prone landscapes in the Tertiary, these were lost with the late Miocene completion of the Andean uplift, which now blocks summer lightning storms from moving into the region. Today these five regions pose a significant fire management challenge due to the annual fire hazard and metropolitan centers juxtaposed with highly flammable vegetation. This challenge varies across the five MTC landscapes as a function of differences in regional fuel loads and population density.
Compilation Report on the Effects of Reservoir Releases on Downstream Ecosystems
No abstract available.
The Florida Everglades ecosystem: climatic and anthropogenic impacts over the last two millennia
No abstract available.
Position statement on the effects of livestock grazing on riparian and stream ecosystems
No abstract available.
Development of assessment methods for hydrologic impacts on western riparian ecosystems
No abstract available.
Selected development needs for assessing ecological risk at the community and ecosystem level
No abstract available.
An analysis of factors contributing to the stability of benthic macroinvertebrate communities in lotic ecosystems
No abstract available.
Book review of Acid deposition and aquatic ecosystems: regional case studies
No abstract available.
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