Aller au contenu principal

page search

Displaying 1297 - 1308 of 4032

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.

Spatial controls on dissolved organic carbon in upland waters inferred from a simple statistical model

Journal Articles & Books
Décembre, 2015

Dissolved organic carbon (DOC) concentrations in upland surface waters in many northern hemisphere industrialised regions are at their highest in living memory, provoking debate over their “naturalness”. Because of the implications for drinking water treatment and supply there is increasing interest in the potential for mitigation through local land management, and for forecasting the likely impact of environmental change. However, the dominant controls on DOC production remain unresolved, hindering the establishment of appropriate reference levels for specific locations.

Farmer-Managed Natural Regeneration Enhances Rural Livelihoods in Dryland West Africa

Journal Articles & Books
Décembre, 2015
Ghana

Declining agricultural productivity, land clearance and climate change are compounding the vulnerability of already marginal rural populations in West Africa. ‘Farmer-Managed Natural Regeneration’ (FMNR) is an approach to arable land restoration and reforestation that seeks to reconcile sustained food production, conservation of soils, and protection of biodiversity. It involves selecting and protecting the most vigorous stems regrowing from live stumps of felled trees, pruning off all other stems, and pollarding the chosen stems to grow into straight trunks.

Water content dynamics in a volcanic ash soil slope in southern Chile

Journal Articles & Books
Décembre, 2015
Chili

Andisols present exceptional physical properties, making up 24%), however, during summer they can reach volumetric water contents near to the permanent wilting point quickly at a depth of 5 cm. The water table altitude was directly related to the temporal changes of θFᵢₑₗd measured at a depth of 50 cm, highlighting the fact that the saturated and unsaturated zones are connected.

Conserving Biodiversity: Practical Guidance about Climate Change Adaptation Approaches in Support of Land-use Planning

Journal Articles & Books
Décembre, 2015

As species' geographic ranges and ecosystem functions are altered in response to climate change, there is a need to integrate biodiversity conservation approaches that promote natural adaptation into land use planning. Successful conservation will need to embrace multiple climate adaptation approaches, but to date they have not been conveyed in an integrated way to help support immediate conservation planning and action in the face of inherent spatial uncertainty about future conditions.

Agricultural drought trends and mitigation in Tillaberí, Niger

Journal Articles & Books
Décembre, 2015
Niger
Global

Whether aggravated agricultural drought in the Sahel is related to a changing climate (meteorological drought, i.e., deficit of rainfall or unfavourable rainfall distribution) or to land use and land degradation (soil-water drought, i.e., decreased water infilitration and water holding capacity) is a much-debated issue.

technique for quantifying groundwater pumping and land subsidence using a nonlinear stochastic poroelastic model

Journal Articles & Books
Décembre, 2015
Taiwan

Subsidence in Yunlin County, Taiwan, is serious and continuous. The Taiwan High Speed Rail (THSR) route crosses the subsidence area and might be affected by differential settlements. It is important to evaluate the pumping quantity for water resource management and to predict the subsidence for land resource management to mitigate the subsidence problem in Taiwan.

Pollution, habitat loss, fishing, and climate change as critical threats to penguins

Journal Articles & Books
Décembre, 2015

Cumulative human impacts across the world's oceans are considerable. We therefore examined a single model taxonomic group, the penguins (Spheniscidae), to explore how marine species and communities might be at risk of decline or extinction in the southern hemisphere. We sought to determine the most important threats to penguins and to suggest means to mitigate these threats. Our review has relevance to other taxonomic groups in the southern hemisphere and in northern latitudes, where human impacts are greater.

Meta-analysis for the transfer of economic benefits of ecosystem services provided by wetlands within two watersheds in Quebec, Canada

Journal Articles & Books
Décembre, 2015
Canada

Climate change will cause major changes in ecosystems. Therefore, it is crucial that climate change policy consider the value of all services that are provided by watershed ecosystems. For this purpose, geospatial data and economic analysis are combined to determine a monetary value for wetland ecosystem goods and services (EGSs) in the watersheds of the Yamaska and Bécancour Rivers (Quebec, Canada). From published studies of wetland economic evaluations, we selected 51 relevant studies from 21 countries and performed a benefit transfer using meta-analysis.

Land Cover Controls the Export of Terminal Electron Acceptors from Boreal Catchments

Journal Articles & Books
Décembre, 2015

NO₃, Mn, Fe, and SO₄act as terminal electron acceptors (TEAs), modifying mineralization pathways and coupling biogeochemical cycles. Although single TEA concentrations and fluxes have been intensively studied, the factors regulating the simultaneous fluxes and molar ratios of TEAs are poorly elucidated. We studied the mean concentrations, exports, and molar ratios of TEAs from 27 boreal catchments differing in land cover (percentage of agricultural land, peatland, forest, and built-up area) during the years 2000–2011.

Water quality, potential conflicts and solutions—an upstream–downstream analysis of the transnational Zarafshan River (Tajikistan, Uzbekistan)

Journal Articles & Books
Décembre, 2015
Tadjikistan
Ouzbékistan

The Central Asian countries are particularly affected by the global climate change. The cultural and economic centers in this mostly arid region have to rely solely on the water resources provided by the rapidly melting glaciers in the Pamir, Tien-Shan and Alay mountains. By 2030, the available water resources will be 30 % lower than today while the water demand will increase by 30 %. The unsustainable land and water use leads to a water deficit and a deterioration of the water quality.

Cashew nut production in Indian subcontinent with emphasis on carbon sequestration potential in a changing global climate scenario

Journal Articles & Books
Décembre, 2015
Inde
Viet Nam
Nigéria

India has a maximum area (21.6%) under cashew nut and is the third largest producer (17.3%) of raw nuts in the world. The country is the second largest exporter, accounting for 34% of the world’s export of cashew kernels having a comparative advantage in production and processing on account of its cheap and skilled labour force. The yields in India are poor at 860 kg/ha as compared to 4,125 kg/ha in Vietnam and 2,000 kg/ha in Nigeria.