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Long-Term Fire Effects on Native and Invasive Grasses in Protected Area Sagebrush Steppe

Journal Articles & Books
Dezembro, 2016
Estados Unidos

Following western settlement, fire was suppressed directly and indirectly by Euro-American land management practices. Currently, reintroduction of fire into sagebrush steppe systems may be desirable, but long-term fire effects are not well-known. In this 15-year study we used a generalized linear mixed modeling approach to analyze the response of native and invasive grass species to fire in an Artemisia tridentata subsp. wyomingensis (Wyoming big sagebrush) community in north-central Oregon, United States.

Variation between bee communities on a sand dune complex in the Great Basin Desert, North America: Implications for sand dune conservation

Journal Articles & Books
Dezembro, 2009
América do Norte

Sand dunes across the Mojave and Great Basin Deserts house rich bee communities. The pollination services these bees provide can be vital in maintaining the diverse, and often endemic, dune flora. These dune environments, however, are threatened by intense off-highway vehicle (OHV) use. Conservation efforts adopted by land managers often consist of setting aside a portion of a dune system that is off-limits to OHV use, but little work has been done showing the extent to which this protects native bee communities.

Balancing the economic, social and environmental dimensions of agro-ecosystems: An integrated modeling approach

Journal Articles & Books
Dezembro, 2009

There is an increasing need to view agro-ecosystems and to identify remedial management practices in a holistic way. An integrated model based on the driving force-pressure-state-impact-response approach was developed as a tool to assess the effects of policies for improving decision making for the sustainability of agro-ecosystems. An economic model was linked to a process-based biophysical model by a meta-model. Then, a holistic indicator-based impact assessment system was linked to the integrated model to assess policy instruments.

Performance of Quantitative Vegetation Sampling Methods Across Gradients of Cover in Great Basin Plant Communities

Journal Articles & Books
Dezembro, 2013

Resource managers and scientists need efficient, reliable methods for quantifying vegetation to conduct basic research, evaluate land management actions, and monitor trends in habitat conditions. We examined three methods for quantifying vegetation in 1-ha plots among different plant communities in the northern Great Basin: photography-based grid-point intercept (GPI), line-point intercept (LPI), and point-quarter (PQ). We also evaluated each method for within-plot subsampling adequacy and effort requirements relative to information gain.

Native maize landraces from Los Tuxtlas, Mexico show varying mycorrhizal dependency for P uptake

Journal Articles & Books
Dezembro, 2014
México

Different degrees of dependency on the activity of arbuscular mycorrhizal fungi (AMF) exist between native maize landraces and hybrids. In Los Tuxtlas, Mexico, the Popoluca people maintain a traditional polycultural land management with more than 15 native landraces of maize; however, it is not known whether the recent substitution of local maize for improved hybrids and fertilization has affected the integrity of the mycorrhizal symbiosis in these naturally phosphorus-poor systems.

Traditional perennial crop-based agroforestry in West Java: the tradeoff between on-farm biodiversity and income

Journal Articles & Books
Dezembro, 2010

Agroforestry systems have been re-evaluated with a renewed scientific interest as appropriate models for achieving sustainable production while maintaining planned and associated biodiversity and agroecosystem functioning. Traditional bamboo-tree gardens in West Java are known to play substantial ecological and socioeconomic roles. In this study, we attempted to elucidate the relationship between income generation and biodiversity by studying 83 bamboo-tree gardens that varied in species composition and degree of commercialization.

effect of fireline intensity on woody fuel consumption in southern Australian eucalypt forest fires

Journal Articles & Books
Dezembro, 2011
Austrália

SummaryThe relationship between woody fuel consumption and fireline intensity was assessed using data collected at controlled fires and wildfires in south-western Western Australia, central Victoria and south-eastern New South Wales. The combined dataset consisted of fires in a range of dry eucalypt forests. Fire behaviour varied from slow, self-extinguishing prescribed burns to intense, fast—moving fires burning under conditions of extreme fire danger. Fireline intensity ranged from 50 kW m⁻ˡ to

Plant use and management in homegardens and swiddens: evidence from the Bolivian Amazon

Journal Articles & Books
Dezembro, 2010
Bolívia

Amazonian plant management is perhaps nowhere as intense as in homegardens and swiddens. A quantitative ethnobotanical study was conducted in Indigenous Territory and National Park Isiboro-Sécure, Bolivia, to investigate plant use and management in homegardens and swiddens by local Yuracaré and Trinitario ethnic groups. Ethnobotanical data of plants were obtained from 11 Yuracaré and 11 Trinitario participants through semistructured interviews.

Enjeux fonciers, exploitation des ressources naturelles et Forêts des Communautés Locales en périphérie de Kinshasa, RDC

Journal Articles & Books
Dezembro, 2011
República Democrática do Congo

Land issues, exploitation of natural resources, and Forests of Rural Communities in the periphery of Kinshasa, DRC. Peri-urban forests are under strong anthropic pressure. Any activity needs a previous identification of stakeholders, landscape perception, socio-economic trends in local communities and their relationships with land and natural resources. Kinshasa (capital of Democratic Republic of Congo, DRC) is a 10 millions inhabitants city with rapid growth and increasing impacts on surrounding villages linked with forest natural resources.

Detecting changes in biomass productivity in a different land management regimes in drylands using satellite‐derived vegetation index

Journal Articles & Books
Dezembro, 2014

We investigated the use of a satellite‐derived vegetation index to detect changes in biomass productivity in different land management regimes in drylands of the Northern Negev. Two well‐documented management regimes, conservation and afforestation using a contour trenching technique were monitored. Biomass data on annual vegetation were collected from field survey and compared to a time series of the Normalized Difference Vegetation Index (NDVI). A significant relationship between NDVI and biomass (r� =� 0.83, P�

Assessing the effects of agricultural management practices on carbon fluxes: Spatial variation and the need for replicated estimates of Net Ecosystem Exchange

Journal Articles & Books
Dezembro, 2010

Replicated measurements of Net Ecosystem CO₂ Exchange (NEE) were made on four arable plots using two eddy covariance (EC) towers that were moved at regular intervals. Replicated plots were created by dividing a large arable field into four approximately equal areas (∼2.5ha). Regular adjustments of the EC measurement height (1.5-1.9m) due to seasonal changes in canopy height ensured that the analyzed fluxes were derived from the individual plots. This was sufficient to make high-quality flux measurements with the energy balance accounting for up to 96% of the available energy in the system.