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1.
J Environ Manage ; 327: 116874, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36446193

RESUMEN

The EU's Forest Law Enforcement, Governance and Trade Action Plan (FLEGT) adopted in 2003 includes bilateral trade agreements known as Voluntary Partnership Agreements (VPAs) signed between the EU and timber-supplying countries. The EU has invested more than 1.5 billion euros in VPAs; however, only one of the seven concerned countries has managed to complete all the necessary requirements to expire FLEGT licences. Since there is no research that comprehensively integrates the scientific evidence regarding the effects of this policy, this study systematically reviews all empirical scientific studies on the effects of VPAs. We found that almost all relevant studies are case reports that use qualitative data and focus on only one country at a time, mainly Ghana, Cameroon, or Indonesia. The evidence suggests that while VPAs have contributed to the establishment of governance structures, tools, and procedures they have not been able to solve social problems (i.e., inequality and injustice) and have potentially harmed the economies of EU timber suppliers. Evidence on the effects of VPAs on illegal logging and trade and the environment remains limited. Thus, future research should focus on more countries; use a greater range of methods, including comparative experimental designs; explore possible intended effects on under-researched categories; and systematically investigate unintended effects on other categories within and outside the forestry sector.


Asunto(s)
Conservación de los Recursos Naturales , Agricultura Forestal , Conservación de los Recursos Naturales/métodos , Agricultura Forestal/métodos , Bosques , Indonesia , Ghana
2.
Sci Rep ; 12(1): 19653, 2022 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-36385148

RESUMEN

Anthropogenic climate change causes more frequent and intense fluctuations in the El Niño Southern Oscillation (ENSO). Understanding the effects of ENSO on agricultural systems is crucial for predicting and ameliorating impacts on lives and livelihoods, particularly in perennial tree crops, which may show both instantaneous and delayed responses. Using cocoa production in Ghana as a model system, we analyse the impact of ENSO on annual production and climate over the last 70 years. We report that in recent decades, El Niño years experience reductions in cocoa production followed by several years of increased production, and that this pattern has significantly shifted compared with prior to the 1980s. ENSO phase appears to affect the climate in Ghana, and over the same time period, we see corresponding significant shifts in the climatic conditions resulting from ENSO extremes, with increasing temperature and water stress. We attribute these changes to anthropogenic climate change, and our results illustrate the big data analyses necessary to improve understanding of perennial crop responses to climate change in general, and climate extremes in particular.


Asunto(s)
Cambio Climático , Árboles , El Niño Oscilación del Sur , Productos Agrícolas , Temperatura
3.
Glob Chang Biol ; 25(8): 2661-2677, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31006150

RESUMEN

Terrestrial net primary productivity (NPP) is an important metric of ecosystem functioning; however, there are little empirical data on the NPP of human-modified ecosystems, particularly smallholder, perennial crops like cocoa (Theobroma cacao), which are extensive across the tropics. Human-appropriated NPP (HANPP) is a measure of the proportion of a natural system's NPP that has either been reduced through land-use change or harvested directly and, previously, has been calculated to estimate the scale of the human impact on the biosphere. Additionally, human modification can create shifts in NPP allocation and decomposition, with concomitant impacts on the carbon cycle. This study presents the results of 3 years of intensive monitoring of forest and smallholder cocoa farms across disturbance, management intensity, distance from forest and farm age gradients. We measured among the highest reported NPP values in tropical forest, 17.57 ± 2.1 and 17.7 ± 1.6 Mg C ha-1  year-1 for intact and logged forest, respectively; however, the average NPP of cocoa farms was still higher, 18.8 ± 2.5 Mg C ha-1  year-1 , which we found was driven by cocoa pod production. We found a dramatic shift in litterfall residence times, where cocoa leaves decomposed more slowly than forest leaves and shade tree litterfall decomposed considerably faster, indicating significant changes in rates of nutrient cycling. The average HANPP value for all cocoa farms was 2.1 ± 1.1 Mg C ha-1  year-1 ; however, depending on the density of shade trees, it ranged from -4.6 to 5.2 Mg C ha-1  year-1 . Therefore, rather than being related to cocoa yield, HANPP was reduced by maintaining higher shade levels. Across our monitored farms, 18.9% of farm NPP was harvested (i.e., whole cocoa pods) and only 1.1% (i.e., cocoa beans) was removed from the system, suggesting that the scale of HANPP in smallholder cocoa agroforestry systems is relatively small.


Asunto(s)
Cacao , Ecosistema , África Occidental , Carbono , Granjas , Bosques , Humanos , Árboles
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