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Productividad, consumo y eficiencia biológica en vacas Frisón Neozelandés y F1 (Jersey-Frisón Neozelandés) paridas a fines de invierno en la X Región, Chile

Journal Articles & Books
декабря, 2004
Chile

Con la finalidad de evaluar productividad, consumo y eficiencia biológica en vacas Frisón Neozelandés (FN) y F1 Jersey-Frisón Neozelandés a pastoreo, se emplearon 23 vacas FN y 24 F1, primíparas, paridas entre el 23/7 y el 27/9 de 2001, en la Estación Experimental Oromo, Universidad de Chile, X Región. La información se recopiló en tres períodos, de 21 días cada uno. Al inicio de estos, las vacas se encontraban en 66, 126 y 220 días de lactancia. Los animales fueron pesados diariamente con el fin de obtener el peso vivo (PV) promedio y la tasa de variación del peso.

Spatiotemporal mapping of the dry season vegetation response of sagebrush steppe

Journal Articles & Books
декабря, 2004

The vegetation dynamics of semi-arid and arid landscapes are temporally and spatially heterogeneous and subject to various disturbance regimes that act on decadal scales. Traditional field-based monitoring methods have failed to sample adequately in time and space in order to capture this heterogeneity and thus lack the spatial extent and the long-term continuous time series of data necessary to detect anomalous dynamics in landscape behavior.

Abomasal parasites in wild sympatric cervids, red deer, Cervus elaphus and fallow deer, Dama dama, from three localities across central and western Spain: relationship to host density and park management

Journal Articles & Books
декабря, 2004
Spain

A survey of abomasal parasites in cervids from Central Spain was conducted at 3 sites, Quintos de Mora (Toledo), Maluéñez de Arriba (Cáceres), and La Herguijuela (Cáceres). Commonly occurring helminths belonged to 3 polymorphic species of the Ostertagiinae: Spiculopteragia asymmetrica/S. quadrispiculata, Ostertagia leptospicularis/O. kolchida, and O. drozdzi/O. ryjikovi. Trichostrongylus axei was found in very few cases. Ostertagia drozdzi/O. ryjikovi and the minor male morphotype, S. quadrispiculata, are reported for the first time in red deer from Spain.

Worm control for small ruminants in tropical Asia

Journal Articles & Books
декабря, 2004

ACIAR funded a collaborative project between research organisations in Southeast Asia for ILRI and regional partners to explore new ways to control helminth parasites in the tropics. The project aimed to increase small ruminant production in Southeast Asia by controlling internal parasites, which are one of the major constraints to sheep and goat production in the tropics. Control of internal parasites also provides an avenue for general improvement in husbandry methods.

Assessment of soil organic carbon in semi-arid Sudan using GIS and the CENTURY model

Journal Articles & Books
декабря, 2003
Sudan

Using the UNFCCC as a basis, and the objectives of estimating soil organic carbon (SOC) changes during the period 1900–2100, a spatially explicit database of climate, land cover and soil texture was compiled for a 262,000 km2 region in semi-arid Sudan. The area is characterized by low input cultivation of millet, sorghum and sesamé combined with livestock grazing. By integrating the database with the CENTURY ecosystem model, we were able to estimate historical, current and future pools of SOC as a function of land management and climate.

Fertility management and landscape position: farmers' use of nutrient sources in western Niger and possible improvements

Journal Articles & Books
декабря, 2003
Niger

Poor millet growth and yields in Niger are commonly attributed to rainfall deficits and low soil nutrient content. Land management by local farmers is done as a function of soil types, crops, and available resources. Farmer management practices in millet fields located on four different landscape positions were studied in a village in western Niger located near the 600 mm isohyet. Average distance from homestead to field was 980 m, with fields in the valley bottom much closer (average 225 m) and fields on the plateau much further (average 2300 m).

environmental narrative of Inland Northwest United States forests, 1800–2000

Journal Articles & Books
декабря, 2003
United States of America

Fire was arguably the most important forest and rangeland disturbance process in the Inland Northwest United States for millennia. Prior to the Lewis and Clark expedition, fire regimes ranged from high severity with return intervals of one to five centuries, to low severity with fire-free periods lasting three decades or less. Indoamerican burning contributed to the fire ecology of grasslands and lower and mid-montane dry forests, especially where ponderosa pine was the dominant overstory species, but the extent of this contribution is difficult to quantify.

Managing woodlands for income maximisation in western Queensland, Australia: clearing for grazing versus timber production

Journal Articles & Books
декабря, 2003
Australia

Queensland, Australia, has a proud pastoral history; however, the private and social benefits of continued woodland clearing for pasture development are unlikely to be as pronounced as they had been in the past. The environmental benefits of tree retention in arid regions of the State are now better appreciated and market opportunities have arisen for the unique timbers of western Queensland.

Resource use conflicts: the future of the Kalahari ecosystem

Journal Articles & Books
декабря, 2003

The Kalahari ecosystem is characterized by natural resource conflicts and land-use pressure resulting from intensification of human activities. This paper addresses three issues of concern associated with the Kalahari ecosystem resource management: (i) the major land-use/land cover shifts in the Kalahari ecosystem since 1970 and the resulting pattern in vegetation species composition, cover and density; (ii) the possible explanations for the observed shifts; and (iii) the possible resource conflicts likely to arise.

set of guidance for the management of grazing Units in the cereal-sheep system of Castile-La Mancha (South-Central Spain)

Journal Articles & Books
декабря, 2003

Extensive livestock farming systems in the Less Favored Areas (LFA) of the European Union (EU) are under social stress and requirement to adapt their production practices to new economic and social realities. This research argues that a restructuring plan for the cereal-sheep system of Castile-La Mancha may represent economic and ecological synergies. The potential implementation of a technical strategy (integrating cereal and sheep farming and increasing acreage of annual forage legumes) has been tested within a community-based research project carried out over three phases.

Degradation and recovery processes in arid grazing lands of central Australia Part 3: implications at landscape scale

Journal Articles & Books
декабря, 2003
Australia

Using data from previous studies, we tested two hypotheses about the impacts of grazing in a naturally heterogeneous landscape in arid central Australia: (1) that grazing leads to net change of resources at a paddock or landscape scale, and (2) that water and nutrients remain coupled as they move through the landscape. We found that key nutrients were likely to be lost at the landscape scale as grazing increased, rather than just being redistributed. Water infiltration increased but runoff was probably lost more readily due to the lack of barriers to flow.

Assigning life-history traits to plant species to better qualify arid land degradation in Presaharian Tunisia

Journal Articles & Books
декабря, 2003
Tunisia

Apart from a decrease in total perennial plant cover, degradation of North-African arid lands is not easy to qualify. Yet, simple and comprehensive yardsticks are necessary to assess degradation. We assigned components of competitive ability (C), stress tolerance (S) and ruderality (R) to 15 common perennials of Presaharian Tunisia. We used for that purpose phyto-ecological studies, data about life-form, grazing value and demography and circumstantial data.