The paper reveals that ever since the 1950s, after the first land reform of distributing landownership (or possession under public ownership) to small farmers, the irrational and polyopolisticland use by able-bodied part-time and absent small farmers earning higher off-farm income butunwilling to lease the under-producing land beyond their family consumption need to full-timefarmers, has been a global obstacle with both public and private land ownership, traditional andmodern agriculture, fragmented small and consolidatorily enlarged land, low and high incomeeconomies, food under-self-suffi
We used the process-oriented niche model CLIMEX to estimate the potential global distribution of serrated tussock under projected future climates. Serrated tussock is a drought-tolerant, wind- and human-dispersed grass of South American origin that has invaded pastures in Australia, Europe, New Zealand, and South Africa. The likely effect of climate change on its potential global distribution was assessed by applying six climate-change scenarios to a previously developed model.
The introduction to this set of papers highlights four challenges to the large-scale analysis of population growth at protected area edges in Africa and Latin America undertaken by George Wittemyer and colleagues in their 2008 paper published in Science. First, it raises questions about their sampling procedures, given national-level variation in systems of protected area designation and protected area estates. Second, it challenges the largely economic model of migration decisions that underlies their analysis.
In the Andean region of South America, understanding communities’ water perceptions is particularly important for water management as many rural communities must decide by themselves if and how they will protect their micro-watersheds and distribute their water. In this study we examine how Water User Associations in the Eastern Andes of Colombia perceive water scarcity and the relationship between this perception and observed climate, land use, and demographic changes. Results demonstrate a complex relationship between perceptions and observed changes.
This study assesses the presence of a forest transition - that is, a shift from net deforestation to net reforestation - in Vietnam during the 1990s, and describes its key attributes relevant for global environmental change issues. Using Fuzzy Kappa and other indicators, we compared forest cover estimates and spatial patterns from global and national land cover maps from the early and late 1990s, and compiled other available statistics for years before and after that period.
Az élelmiszerárak növekedése 2006–2008 között a világ egyes térségeiben zavargásokhoz és a politikai stabilitás megrendüléséhez vezetett. Különösen fejlődő országokban súlyos a helyzet, ahol a legszegényebb rétegek jövedelmük döntő hányadát élelmiszerekre költik. Az agrárpiacokon a kereslet vált meghatározóvá, mennyiségi (humáncélú és ipari felhasználás rohamos növekedése) és minőségi értelemben (élelmiszer-fogyasztás szerkezetének változása).
Habitat models constitute useful instruments for understanding species-habitat interactions and can constitute helpful conservation tools. The Upper Paraná Atlantic Forest (UPAF) of South America still holds the world’s southernmost jaguar (Panthera onca) population.
There is widespread recognition that forestry carbon credits can reduce the net emissions of carbon into the atmosphere. Designing systems to sequester carbon, however, has proven difficult due to a number of efficiency issues, including leakage. Leakage occurs when policy makers develop carbon projects in specific places which protect some parcels of land, but leave other parcels of land unprotected. This analysis uses a newly developed model of global land use change from an established forestry and land use model, described in Sohngen et al.
For some fifteen years, dairy cattle farming has been considerably developing in various parts of the Andes. Milk is transformed into cheese or sold fresh, giving rural families a regular income which secures their food supply. The stock-rearing practices in these Andean dairying systems are unrecognized and are often considered, wrongly, as underperforming and inadequate.