The Economic Case for Landscape Restoration in Latin America

Degraded lands—lands that have lost some degree of their natural productivity through human activity—account for over 20 percent of forest and agricultural lands in Latin America and the Caribbean. Some 300 million hectares of the region's forests are considered degraded, and about 350 million hectares are now classified as deforested. The agriculture and forestry sectors are growing and exerting great pressure on natural areas. With the region expected to play an increasingly important role in global food security, this pressure will continue to ratchet up. In addition, land degradation is a major driver in greenhouse gas emissions in the region. Forest and landscape restoration can offer a solution to these increasing pressures

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ABSTRACT: δ-Stearolactone was prepared from oleic acid using concentrated sulfuric acid under various conditions in the presence of polar, nonparticipating solvents. δ-Stearolactone was formed in as high as 15:1 ratios over the thermodynamic product, γ-lactone, in the presence of methylene chloride, 100% wt/vol, at room temperature with two equivalents of sulfuric acid for 24 h. This procedure is applicable to other olefinic fatty acids such as estolides and fatty acid methyl esters. Temperature plays a role in the regioselectivity of the cyclization for δ-lactone, as lower temperatures (20°C) gave higher δ/γ ratios. At higher temperatures (50°C) in the presence of sulfuric acid and methylene chloride the yield of lactone was 75% but with a δ/γ ratio of only 0.3:1. Cyclization of oleic acid to lactone also occurred with other acids. Oleic acid underwent reaction with perchloric acid, one equivalent, in the absence of solvent at 50°C, which yielded δ-lactone in a modest yield with a 3.1 δ/γ ratio. The same temperature effect was observed with perchloric acid that was observed in the case of sulfuric acid. Because δ-stearolactone is much more reactive than the corresponding fatty acid, fatty acid ester, or γ-lactone, we believe that it will be a useful synthon for many new industrial products including new biodegradable detergents

Calorie restriction and not glucagon-like peptide-1 explains the acute improvement in glucose control after gastric bypass in Type 2 diabetes.

AIMS: To compare directly the impact of glucagon-like peptide-1 secretion on glucose metabolism in individuals with Type 2 diabetes listed for Roux-en-Y gastric bypass surgery, randomized to be studied before and 7 days after undergoing Roux-en-Y gastric bypass or after following a very-low-calorie diet. METHODS: A semi-solid meal test was used to investigate glucose, insulin and glucagon-like peptide-1 response. Insulin secretion in response to intravenous glucose and arginine stimulus was measured. Hepatic and pancreatic fat content was quantified using magnetic resonance imaging. RESULTS: The decrease in fat mass was almost identical in the Roux-en-Y gastric bypass and the very-low-calorie diet groups (3.0±0.3 and 3.0±0.7kg). The early rise in plasma glucose level and in acute insulin secretion were greater after Roux-en-Y gastric bypass than after a very-low-calorie diet; however, the early rise in glucagon-like peptide-1 was disproportionately greater (sevenfold) after Roux-en-Y gastric bypass than after a very-low-calorie diet. This did not translate into a greater improvement in fasting glucose level or area under the curve for glucose. The reduction in liver fat was greater after Roux-en-Y gastric bypass (29.8±3.7 vs 18.6±4.0%) and the relationships between weight loss and reduction in liver fat differed between the Roux-en-Y gastric bypass group and the very-low-calorie diet group. CONCLUSIONS: This study shows that gastroenterostomy increases the rate of nutrient absorption, bringing about a commensurately rapid rise in insulin level; however, there was no association with the large post-meal rise in glucagon-like peptide-1, and post-meal glucose homeostasis was similar in the Roux-en-Y gastric bypass and very-low-calorie diet groups. (Clinical trials registry number: ISRCTN11969319.)

Focal points and bargaining

This is a contribution to the growing experimental literature on how trial-and-error adjustment processes can establish a convention for coordination on an equilibrium in a game. A simple bargaining game introduced by Nash is used for this purpose. Subjects are conditioned in different treatments to use four different bargaining solutions. The stability of the conditioning is then studied as the bargaining game is played over an extended period. The data obtained is unusually sharp. In the long run, the median subject behaves as though optimizing often down to a fraction of a penny. The results are therefore not supportive of the view that strategic considerations in such situations can be neglected in favor of a study of fairness norms. Indeed, the equilibrium actually achieved in a session turns out to be a very good predictor of what the median subject says is “fair” in the game after play is over.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45837/1/182_2005_Article_BF01240133.pd

Integrating community assembly and biodiversity to better understand ecosystem function: the Community Assembly and the Functioning of Ecosystems (CAFE) approach.

The research of a generation of ecologists was catalysed by the recognition that the number and identity of species in communities influences the functioning of ecosystems. The relationship between biodiversity and ecosystem functioning (BEF) is most often examined by controlling species richness and randomising community composition. In natural systems, biodiversity changes are often part of a bigger community assembly dynamic. Therefore, focusing on community assembly and the functioning of ecosystems (CAFE), by integrating both species richness and composition through species gains, losses and changes in abundance, will better reveal how community changes affect ecosystem function. We synthesise the BEF and CAFE perspectives using an ecological application of the Price equation, which partitions the contributions of richness and composition to function. Using empirical examples, we show how the CAFE approach reveals important contributions of composition to function. These examples show how changes in species richness and composition driven by environmental perturbations can work in concert or antagonistically to influence ecosystem function. Considering how communities change in an integrative fashion, rather than focusing on one axis of community structure at a time, will improve our ability to anticipate and predict changes in ecosystem function

Global change effects on plant communities are magnified by time and the number of global change factors imposed

Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (<10 y). In contrast, long-term (≥10 y) experiments show increasing community divergence of treatments from control conditions. Surprisingly, these community responses occurred with similar frequency across the GCD types manipulated in our database. However, community responses were more common when 3 or more GCDs were simultaneously manipulated, suggesting the emergence of additive or synergistic effects of multiple drivers, particularly over long time periods. In half of the cases, GCD manipulations caused a difference in community composition without a corresponding species richness difference, indicating that species reordering or replacement is an important mechanism of community responses to GCDs and should be given greater consideration when examining consequences of GCDs for the biodiversity–ecosystem function relationship. Human activities are currently driving unparalleled global changes worldwide. Our analyses provide the most comprehensive evidence to date that these human activities may have widespread impacts on plant community composition globally, which will increase in frequency over time and be greater in areas where communities face multiple GCDs simultaneously