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1.
Carbon Balance Manag ; 18(1): 14, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37460773

RESUMEN

Greenhouse gas (GHG) accounting of emissions from land use, land-use change, and forestry necessarily involves consideration of landscape fire. This is of particular importance for Australia given that natural and human fire is a common occurrence, and many ecosystems are adapted to fire, and require periodic burning for plant regeneration and ecological health. Landscape fire takes many forms, can be started by humans or by lightning, and can be managed or uncontrolled. We briefly review the underlying logic of greenhouse gas accounting involving landscape fire in the 2020 Australian Government GHG inventory report. The treatment of wildfire that Australia chooses to enact under the internationally agreed guidelines is based on two core assumptions (a) that effects of natural and anthropogenic fire in Australian vegetation carbon stocks are transient and they return to the pre-fire level relatively quickly, and (b) that historically and geographically anomalous wildfires in forests should be excluded from national anthropogenic emission estimates because they are beyond human control. It is now widely accepted that anthropogenic climate change is contributing to increased frequency and severity of forest fires in Australia, therefore challenging assumptions about the human agency in fire-related GHG emissions and carbon balance. Currently, the national inventory focuses on forest fires; we suggest national greenhouse gas accounting needs to provide a more detailed reporting of vegetation fires including: (a) more detailed mapping of fire severity patterns; (b) more comprehensive emission factors; (c) better growth and recovery models from different vegetation types; (d) improved understanding how fires of different severities affect carbon stocks; and (e) improved analysis of the human agency behind the causes of emissions, including ignition types and fire-weather conditions. This more comprehensive accounting of carbon emissions would provide greater incentives to improve fire management practices that reduce the frequency, severity, and extent of uncontrolled landscape fires.

2.
Agrofor Syst ; 97(4): 533-548, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36712175

RESUMEN

Laos is among the top twenty coffee producing country in the world-producing about 39,000 tonnes per year-and most of its production is currently exported to over 26 countries, contributing about 1.1% of the total export value or US$64.3 million in 2019 to Laos' national economy. COVID-19 restrictions on trade and movement of people have largely impacted on coffee markets and production. As a strategic crop in Laos, it is supported by a range of policies and programs to generate greater benefits to both independent smallholder farmers and those involved in cooperatives, including support for agroforestry production models involving coffee and tree crops. However, studies of the profitability of different coffee agroforestry models are limited. This study compares financial returns from four most popular coffee agroforestry models in two coffee production provinces of Laos, before and during COVID-19 pandemic. The data were gathered from 20 farmers, five coffee traders and an integrated coffee processing company. These data were then triangulated with, and supplemented by, interviews with coffee exporters (n = 3) and key informants (n = 4). Financial indicators suggest that all four agroforestry models were profitable before COVID, but profits for cooperative growers were higher than for smallholders due to higher crop productivity and lower costs. Despite higher prices due to COVID restrictions, other factors reduced profitability of all four models and one smallholder model became unprofitable. The reasons for such differences and related policy implications are discussed.

4.
Nat Ecol Evol ; 5(7): 1003-1010, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33972737

RESUMEN

The 2019-20 wildfires in eastern Australia presented a globally important opportunity to evaluate the respective roles of climatic drivers and natural and anthropogenic disturbances in causing high-severity fires. Here, we show the overwhelming dominance of fire weather in causing complete scorch or consumption of forest canopies in natural and plantation forests in three regions across the geographic range of these fires. Sampling 32% (2.35 Mha) of the area burnt we found that >44% of the native forests suffered severe canopy damage. Past logging and wildfire disturbance in natural forests had a very low effect on severe canopy damage, reflecting the limited extent logged in the last 25 years (4.5% in eastern Victoria, 5.3% in southern New South Wales (NSW) and 7.8% in northern NSW). The most important variables determining severe canopy damage were broad spatial factors (mostly topographic) followed by fire weather. Timber plantations affected by fire were concentrated in NSW and 26% were burnt by the fires and >70% of the NSW plantations suffered severe canopy damage showing that this intensive means of wood production is extremely vulnerable to wildfire. The massive geographic scale and severity of these Australian fires is best explained by extrinsic factors: an historically anomalous drought coupled with strong, hot dry westerly winds that caused uninterrupted, and often dangerous, fire weather over the entire fire season.


Asunto(s)
Eucalyptus , Incendios Forestales , Bosques , Nueva Gales del Sur , Victoria
6.
Ambio ; 46(3): 291-310, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27854070

RESUMEN

Global economic change and policy interventions are driving transitions from long-fallow swidden (LFS) systems to alternative land uses in Southeast Asia's uplands. This study presents a systematic review of how these transitions impact upon livelihoods and ecosystem services in the region. Over 17 000 studies published between 1950 and 2015 were narrowed, based on relevance and quality, to 93 studies for further analysis. Our analysis of land-use transitions from swidden to intensified cropping systems showed several outcomes: more households had increased overall income, but these benefits came at significant cost such as reductions of customary practice, socio-economic wellbeing, livelihood options, and staple yields. Examining the effects of transitions on soil properties revealed negative impacts on soil organic carbon, cation-exchange capacity, and aboveground carbon. Taken together, the proximate and underlying drivers of the transitions from LFS to alternative land uses, especially intensified perennial and annual cash cropping, led to significant declines in pre-existing livelihood security and the ecosystem services supporting this security. Our results suggest that policies imposing land-use transitions on upland farmers so as to improve livelihoods and environments have been misguided; in the context of varied land uses, swidden agriculture can support livelihoods and ecosystem services that will help buffer the impacts of climate change in Southeast Asia.


Asunto(s)
Agricultura/métodos , Agricultura/tendencias , Asia Sudoriental , Cambio Climático , Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/tendencias , Ecosistema
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