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Accelerating the domestication of forest trees in a changing world

Journal Articles & Books
december, 2012

In light of impending water and arable land shortages, population growth and climate change, it is more important than ever to examine how forest tree domestication can be accelerated to sustainably meet future demands for wood, biomass, paper, fuel and biomaterials. Because of long breeding cycles, tree domestication cannot be rapidly achieved through traditional genetic improvement methods alone. Integrating modern genetic and genomic techniques with conventional breeding will expedite tree domestication.

Past and future seasonal variation in pH and metal concentrations in runoff from river basins on acid sulphate soils in Western Finland

Journal Articles & Books
december, 2012

Drainage of acid sulphate soils (ASS) increases oxidation, leading to extensive leaching of acidity and metals to rivers (Al, Cd, Cr, Fe, Ni and Zn). This is often apparent during high runoff periods in spring and autumn after long dry periods with low groundwater levels and associated ASS oxidation. Regression models were used to study changes in these water quality variables according to various discharge scenarios. The knowledge of seasonal patterns of water quality variables in future is important for planning land use of the catchments in relation to WFD of European Union.

Accounting for space and time in soil carbon dynamics in timbered rangelands

Journal Articles & Books
december, 2012

Employing rangelands for climate change mitigation is hindered by conflicting reports on the direction and magnitude of change in soil organic carbon (ΔSOC) following changes in woody cover. Publications on woody thickening and deforestation, which had led to uncertainty in ΔSOC, were re-evaluated, and the dimensional-dependence of their data was determined. To model the fundamentals of SOC flux, linked SOC pools were simulated with first-order kinetics. Influences from forest development timelines and location of mature trees, with a potential for deep-set roots, were considered.

Probabilistic uncertainty specification: Overview, elaboration techniques and their application to a mechanistic model of carbon flux

Journal Articles & Books
december, 2012

It is widely recognised that the appropriate representation for expert judgements of uncertainty is as a probability distribution for the unknown quantity of interest. However, formal elicitation of probability distributions is a non-trivial task. We provide an overview of this field, including an outline of the process of eliciting knowledge from experts in probabilistic form. We explore approaches to probabilistic uncertainty specification including direct elicitation and Bayesian analysis.

Community perceptions of REDD+: a case study from Papua New Guinea

Journal Articles & Books
december, 2012
Papua New Guinea

REDD projects have received considerable attention for their potential to mitigate the effects of climatic change. However, the existing literature has been slow to assess the impacts of proposed REDD projects on the livelihoods of forest communities in the developing world, or the implications of these local realities for the success of REDD+ initiatives in general. This study presents ethnographic research conducted with communities within the April-Salomei pilot REDD+ Project in Papua New Guinea (PNG).

Eliciting expert knowledge to inform landscape modeling of conservation scenarios

Journal Articles & Books
december, 2012

Conservation and land management organizations such as The Nature Conservancy are developing strategies to distribute conservation efforts over larger areas. Relative to fee-simple protection efforts, strategies that allow ecologically sustainable timber harvest and recreation activities, such as working forest conservation easements, should yield greater socioeconomic benefits (ecosystem services) with less investment per area without significantly compromising the conservation of biodiversity (ecological targets).

Epistemic uncertainty in predicting shorebird biogeography affected by sea-level rise

Journal Articles & Books
december, 2012

Accurate spatio-temporal predictions of land-cover are fundamentally important for assessing geomorphological and ecological patterns and processes. This study quantifies the epistemic uncertainty in the species distribution modeling, which is generated by spatio-temporal gaps between the biogeographical data, model selection and model complexity. Epistemic uncertainty is generally given by the sum of subjective and objective uncertainty. The subjective uncertainty generated by the modeler-choice in the manipulation of the environmental variables was analyzed.

Quantifying changes in flooding and habitats in the Tonle Sap Lake (Cambodia) caused by water infrastructure development and climate change in the Mekong Basin

Journal Articles & Books
december, 2012
Cambodia

The economic value of the Tonle Sap Lake Floodplain to Cambodia is arguably among the highest provided to a nation by a single ecosystem around the world. Nonetheless, the Mekong River Basin is changing rapidly due to accelerating water infrastructure development (hydropower, irrigation, flood control, and water supply) and climate change, bringing considerable modifications to the flood pulse of the Tonle Sap Lake in the foreseeable future.

Microbial enzyme stoichiometry and nutrient limitation in US streams and rivers

Journal Articles & Books
december, 2012
United States of America

We analyzed water and sediment chemistry, catchment land cover, and microbial dehydrogenase (DHA) and extracellular enzymes activities (EEA) related to microbial C, N, P, and S acquisition in more than 2100 1st–10th order streams. The streams and their catchments represented gradients in water and sediment chemistry (C, N, P, S) and land cover (% forest, % wetland, % row crop agriculture) against which to compare biofilm and sediment DHA and EEA, and to estimate the extent of nutrient limitation in US streams and rivers.

Creation and Dissolution of Private Property in Forest Carbon: A Case Study from Papua New Guinea

Journal Articles & Books
december, 2012
Guinea
Papua New Guinea

This paper shows how the prospect of a forest carbon market in Papua New Guinea added a new element of instability to national forest policy and property processes that were already moving in contradictory directions. In particular we examine attempts by foreign investors to forge voluntary carbon agreements with customary landowners after the Bali climate change conference of 2007, and the mobilization of state institutions to counter these ‘private dealings’.