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Expansion of the global terrestrial protected area system

Journal Articles & Books
Décembre, 2009
Brésil

Under the Convention on Biological Diversity, the world's governments set a goal of protecting 10% of all ecological regions by 2010. We evaluated progress toward that goal for the world's major terrestrial biomes, realms, and ecoregions. Total land area under any legal protection has increased from previous estimates to 12.9%, a notable achievement, although only 5.8% has strict protection for biodiversity. For biomes, protection ranges from 4% to 25%, with six of 14 biomes still below the 10% level.

Pyric-Herbivory to Promote Rangeland Heterogeneity: Evidence From Small Mammal Communities

Journal Articles & Books
Décembre, 2010

Management of rangelands has largely operated under the paradigm of minimizing spatially discrete disturbances, often under the objective of reducing inherent heterogeneity within managed ecosystems. This has led to a simplified understanding of rangelands and in many cases simplified rangelands. We argue that this type of management focus is incapable of maintaining biodiversity.

Opportunities and challenges for biodiesel fuel

Journal Articles & Books
Décembre, 2011

Fossil fuel resources are decreasing daily. As a renewable energy, biodiesel has been receiving increasing attention because of the relevance it gains from the rising petroleum price and its environmental advantages. This review highlights some of the perspectives for the biodiesel industry to thrive as an alternative fuel, while discussing opportunities and challenges of biodiesel. This review is divided in three parts. First overview is given on developments of biodiesel in past and present, especially for the different feedstocks and the conversion technologies of biodiesel industry.

Land Ownership and Land‐Cover Change in the Southern Appalachian Highlands and the Olympic Peninsula

Journal Articles & Books
Décembre, 1996

Social and economic considerations are among the most important drivers of landscape change, yet few studies have addressed economic and environmental influences on landscape structure, and how land ownership may affect landscape dynamics. Watersheds in the Olympic Peninsula, Washington, and the southern Appalachian highlands of western North Carolina were studied to address two questions: (1) Does landscape pattern vary among federal, state, and private lands?

Growing sustainable tea on Kenyan smallholder farms

Journal Articles & Books
Décembre, 2011
Kenya

This paper describes a partnership between Lipton tea and the Kenya Tea Development Agency (KTDA). The partnership aims to encourage smallholders to produce tea more sustainably and profitably. A Farmer Field School (FFS) approach was used. This has resulted in the development of high levels of social capital, and the programme has resulted in increased annual yields and a renewed focus on improved water and land management. Farmers who have graduated from FFSs have acted as extension agents themselves.

Climate impacts on net primary productivity trends in natural and managed ecosystems of the central and eastern United States

Journal Articles & Books
Décembre, 2009
États-Unis d'Amérique

The central and eastern United States is an important food and timber production region and could potentially be a large-scale carbon sink. These characteristics are functions of the human management of the landscape and favorable soil and climate conditions. Large-scale assessments of carbon uptake and trends in net primary productivity (NPP) have been previously reported for this region using satellite observations, but they cannot quantify the contributions from changes in management and technology independently from climate effects.

Possible impacts of climate change on water quality in streams of the Czech Republic

Journal Articles & Books
Décembre, 2015
République tchèque

The impacts of changes in water temperature and flow on selected water quality parameters, as one of the consequences of climate change, were studied in river catchments in the Czech Republic with little anthropogenic influence. The impact of climate change was manifested by an increase in stream temperature by 1.15°C over 28 years. The selected water quality parameters were dependent on flow, with up to 10-fold increases in the concentrations of ammonia, phosphorus and chlorophyll- a at minimum flow levels.

Informal institutions as mechanisms to address challenges in communal grazing land management in Tigray, Ethiopia

Journal Articles & Books
Décembre, 2011
Éthiopie

The role of institutions providing rules, norms and regulations, in addressing challenges in communal resources management has been debated for several decades. This article analyses the role of informal institutions for addressing shortage of grazing land, conflicts among users of communal grazing land and resistance among users to shift from free grazing to zero grazing in Tigray, Ethiopia. We used in depth interviews and focus group discussions for data collection.

Determination of representative elementary areas for soil redoximorphic features identified by digital image processing

Journal Articles & Books
Décembre, 2011
États-Unis d'Amérique

Photography has been a welcome tool in documenting and conveying qualitative soil information. When coupled with image analysis software, the usefulness of digital cameras can be increased to advance the field of micropedology. The determination of a representative elementary area (REA) still remains a critical information need for soil scientists so that field measurements are independent of sample size and account for spatial heterogeneity.

Context for re-evaluating agricultural source phosphorus loadings to the Great Lakes

Journal Articles & Books
Décembre, 2011

Over the past decade, scientists have been discussing the re-emergence of harmful algal blooms and excessive growth of Cladophora in some areas of the Great Lakes. An observation that has emerged from these discussions is that management of non-point or diffuse sources of phosphorus will be more important in the future in order to address symptoms of eutrophication in the nearshore. This paper provides context for this renewed focus on managing non-point source tributary loads and is based primarily on materials and discussions from the Great Lakes P Forum.