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Rangelands: Where Anthromes Meet Their Limits

Peer-reviewed publication
Junho, 2017

Defining rangelands as anthromes enabled Ellis and Ramankutty (2008) to conclude that more than three-quarters of Earth’s land is anthropogenic; without rangelands, this figure would have been less than half. They classified all lands grazed by domestic livestock as rangelands, provided that human population densities were low; similar areas without livestock were excluded and classified instead as ‘wildlands’. This paper examines the empirical basis and conceptual assumptions of defining and categorizing rangelands in this fashion.

World Day to Combat Desertification - 2017

Reports & Research
Junho, 2017
Índia

Since 1995, June 17th has been observed as the "World Day to Combat Desertification - 2017"  The main objective of commemorating WDCD has been to promote public awareness about international efforts to combat desertification and the effects of drought collectively.

This report provides commemoration of WDCD 2017 across india on awraness, workshops, nature camps, schemes and events launched.

This report highlights the activities pertaining to issues related to desertification, land degradation and drought, 

Agent-based modeling of complex social–ecological feedback loops to assess multi-dimensional trade-offs in dryland ecosystem services

Journal Articles & Books
Abril, 2017
China
Eastern Asia

Context: Recent conceptual developments in ecosystem services research have revealed the need to elucidate the complex and unintended relationships between humans and the environment if we are to better understand and manage ecosystem services in practice.

Objectives: This study aimed to develop a model that spatially represents a complex human–environment (H–E) system consisting of heterogeneous social–ecological components and feedback mechanisms at multiple scales, in order to assess multi-dimensional (spatial, temporal, and social) trade-offs in ecosystem services.

Correlation between landscape fragmentation and sandy desertification: a case study in Horqin Sandy Land, China

Journal Articles & Books
Dezembro, 2016
China

The exact roles of landscape fragmentation on sandy desertification are still not fully understood, especially with the impact of different land use types in spatial dimension. Taking patch size and shape into consideration, this paper selected the Ratio of Patch Size and the Fractal Dimension Index to establish a model that reveals the association between the area of bare sand land and the fragmentation of different land use types adjacent to bare sand land.

Rain Use Efficiency, Primary Production and Rainfall Relationships in Desert Rangelands of Tunisia

Journal Articles & Books
Dezembro, 2016
Tunísia

Desert rangelands are characterised by low and highly variable rainfall regime, low forage production and high heterogeneity in the distribution of natural resources. This study was carried out in the desert rangelands of Tunisia to evaluate the response of different rangelands to annual rainfall in terms of aboveground net primary production (ANPP) and rain use efficiency over a 10‐year period (2003–2012). In general, ANPP values were relatively low (123 kg DM ha⁻¹ y⁻¹) but would tend to increase with increasing annual rainfall for all rangeland types.

Simulation of vegetation feedbacks on local and regional scale precipitation in West Africa

Journal Articles & Books
Dezembro, 2016
África Ocidental

Planned changes to land use in West Africa have been proposed to both combat desertification and to preserve biodiversity in the region, however, there is an urgent need for tools to assess the effects of these proposed changes on local and regional scale precipitation. We use a high-resolution, convection-permitting numerical weather prediction (NWP) model to study how the initiation and propagation of mesoscale convective systems (MCS) depends on the surface vegetation cover. The simulations covered a 4-day period during the West African monsoon in August 2006.

Impact of agricultural land use in Central Asia: a review

Journal Articles & Books
Dezembro, 2016
Quirguistão
Cazaquistão
Tajiquistão
Turquemenistão
Usbequistão
Ásia
Ásia Central

Agriculture is major sector in the economy of Central Asia. The sustainable use of agricultural land is therefore essential to economic growth, human well-being, social equity, and ecosystem services. However, salinization, erosion, and desertification cause severe land degradation which, in turn, degrade human health and ecosystem services. Here, we review the impact of agricultural land use in the five countries of Central Asia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan, during 2008–2013 in 362 articles.

Quantitative Mapping and Assessment of Environmentally Sensitive Areas to Desertification in Central Iran

Journal Articles & Books
Dezembro, 2016
Irã

Desertification is one of the main environmental and also social and economic problems facing Iran. Seventeen out of 31 Iranian provinces, which are home to approximately 70% of the total population, are affected by desertification. This study aimed to use geographic information system (GIS) and fuzzy logic for mapping environmentally sensitive areas to desertification based on Mediterranean Desertification and Land Use approach in Isfahan province, central Iran.

Use of Goats Grazing to Restore Pastures Invaded by Shrubs and Avoid Desertification: A Preliminary Case Study in the Spanish Cantabrian Mountains

Journal Articles & Books
Dezembro, 2016
Espanha

Spanish mountains have been affected by the expansion of shrubs and forests since the mid‐20th century. This secondary succession in vegetation has some positive effects, but also drawbacks, such as an increase in fire risk, loss of diversity in land use, a reduction in landscape and cultural value, less water available in river channels and reservoirs, constraints on livestock farming, a reduced number of local species and loss of biodiversity.

European scale analysis of phospholipid fatty acid composition of soils to establish operating ranges

Journal Articles & Books
Dezembro, 2016

Recent preoccupations regarding possible negative effects of pollution, inappropriate land management, climate change, desertification, erosion, compaction or over-exploitation on soils has led to initiatives for the survey of soils. One of them, EcoFINDERS, launched a pan-European survey in order to define normal operating ranges for soil biodiversity and quality, through the use of several methodologies.

Three‐dimensional structure and cyanobacterial activity within a desert biological soil crust

Journal Articles & Books
Dezembro, 2016

Desert biological soil crusts (BSCs) are formed by adhesion of soil particles to polysaccharides excreted by filamentous cyanobacteria, the pioneers and main producers in this habitat. Biological soil crust destruction is a central factor leading to land degradation and desertification. We study the effect of BSC structure on cyanobacterial activity. Micro‐scale structural analysis using X‐ray microtomography revealed a vesiculated layer 1.5–2.5 mm beneath the surface in close proximity to the cyanobacterial location.