Resultados de la búsqueda
Mostrando ítems 1 a 9 de 113.
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Library Resource
Documentos de política y resúmenes
Agricultural land protection near the urban-rural fringe is a goal of manyjurisdictions, including British Columbia, Canada, which uses a provincial-widezoning scheme to prevent subdivisions and non-agricultural uses of the land.Preferential taxes are also used to encourage agricultural use of the land. Small scalehobby farmers are present at the urban fringe near Victoria (the capital), both insideand outside of the Agricultural Land Reserve (ALR).
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Library Resource
Artículos de revistas y libros
México, Canadá, Guatemala, África septentrional, Asia meridional
This paper discusses the centers of origin and diversity for bread wheat; sketches historical patterns in the sources and use of wheat genetic resources in modern plant breeding; identifies and compares indicators of genetic diversity used by social and biological scientists; reviews the relationship of wheat genetic diversity to yield stability and vulnerability to disease; develops a profile of the structure of genetic variation in wheat in the developing world today; and investigates how scientific plant breeding has influenced the structure of genetic variation among the major bread whe
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Library Resource
Artículos de revistas y libros
Canadá, Estados Unidos de América
Recent food crises have highlighted the need to better understand the between-year variability of agricultural production. Although increasing future production seems necessary, the globalization of commodity markets suggests that the food system would also benefit from enhanced supplies stability through a reduction in the year-to-year variability.
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Library Resource
Artículos de revistas y libros
Variants of Indigenous forest management reflect distinct historical and political-economic contexts. Indigenous forest management was largely unrecorded in the colonial period and, in the present, can range from industrial to ecosystem-based forest management, autonomous management and rentier practices. Evidence of Indigenous forest management has assumed political importance in those nation-states that require historical evidence of past land use and occupancy as the basis for negotiation of Indigenous-titled lands.
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Library Resource
Artículos de revistas y libros
Urban freshwaters provide a range of ecosystem services, including stormwater management, water treatment, biodiversity, and aesthetics. Management of freshwaters should aim to maximise as many of these services as possible, but managers are often focused on individual services. To test for the biodiversity value of stormwater management ponds (SMPs) in Ottawa, Canada, 20 SMPs were surveyed for macroinvertebrates using standardised sampling techniques.
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Library Resource
Artículos de revistas y libros
Species distribution modelling (SDM) can help conservation by providing information on the ecological requirements of species at risk. We developed habitat suitability models at multiple spatial scales for a threatened freshwater turtle, Emydoidea blandingii, in Ontario as a case study. We also explored the effect of background data selection and modelling algorithm selection on habitat suitability predictions. We used sighting records, high-resolution land cover data (25m), and two SDM techniques: boosted regression trees; and maximum entropy modelling.
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Library Resource
Artículos de revistas y libros
Canadá, Estados Unidos de América
The province of New Brunswick (NB), Canada and the state of Maine (ME), USA are heavily forested jurisdictions whose forests provide many social, ecological, and economic functions. Roughly a third of NB and ME’s forested land is owned by private, non-industrial owners [sometimes called family forests or woodlot owners]. The choices of thousands of individual parcel owners of forest land determine the fate of these ecosystems. Ownership of forest land implies a social contract between the landowners and the rest of society.
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Library Resource
Documentos de conferencias e informes
Estados Unidos de América, Filipinas, Malasia, China, Indonesia, Australia, Canadá, Tailandia, Nueva Zelandia
The emerging biofuel sector has drawn great interest as an alternative source of fuel for transportation. The expansion of biofuels greatly impacts world agricultural markets, since currently, the primary feedstocks for ethanol and biodiesel production are field crops and their derived products. There is great interest in the potential of countries to expand their biofuel sectors through increased production of feedstocks. The long-term potential for developing first-generation biofuels in many countries depends on a large and constant supply of feedstocks.
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Library Resource
Artículos de revistas y libros
We report estimates of the amount, distribution, and uncertainty of aboveground biomass (AGB) of the different ecoregions and forest land cover classes within the North American boreal forest, analyze the factors driving the error estimates, and compare our estimates with other reported values. A three-phase sampling strategy was used (i) to tie ground plot AGB to airborne profiling lidar metrics and (ii) to link the airborne estimates of AGB to ICESat-GLAS lidar measurements such that (iii) GLAS could be used as a regional sampling tool.
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Library Resource
Artículos de revistas y libros
The boreal forest ecosystem is one of the largest frontier forests of the world, providing many ecological services to society. Boreal forests are also economically important, but forest harvesting and management become increasingly difficult when one moves from south to north in boreal environments. An approach was thus developed to assess the suitability of land units for timber production in a sustainable forest management (SFM) context in the northern boreal forest of Quebec (Canada).
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