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Carbon management in dryland agricultural systems. A review

Journal Articles & Books
december, 2015

Dryland areas cover about 41 % of the Earth’s surface and sustain over 2 billion inhabitants. Soil carbon (C) in dryland areas is of crucial importance to maintain soil quality and productivity and a range of ecosystem services. Soil mismanagement has led to a significant loss of carbon in these areas, which in many of them entailed several land degradation processes such as soil erosion, reduction in crop productivity, lower soil water holding capacity, a decline in soil biodiversity, and, ultimately, desertification, hunger and poverty in developing countries.

Desertification, land use, and the transformation of global drylands

Journal Articles & Books
december, 2015

Desertification is an escalating concern in global drylands, yet assessments to guide management and policy responses are limited by ambiguity concerning what this term means and what processes are involved. In order to provide greater clarity, we propose that desertification assessments be placed within a state change-land use change (SC-LUC) framework. SC-LUC views desertification as state change occurring within the context of particular land uses (such as rangeland or cropland) and interacting with land use change.

Beyond desertification: new paradigms for dryland landscapes

Journal Articles & Books
december, 2015

The traditional desertification paradigm focuses on the losses of ecosystem services that typically occur when grasslands transition to systems dominated by bare (unvegetated) ground or by woody plants that are unpalatable to domestic livestock. However, recent studies reveal complex transitions across a range of environmental conditions and socioeconomic contexts.

Ecological benefit of different revegetated covers in the middle of Hexi corridor, northwestern China

Journal Articles & Books
december, 2015
China

Desertification is one of the major obstacles to the development and utilization of oases in arid and semi-arid regions of China. Revegetation of oases is an effective means of protecting oases from sand invasion (the main cause of desertification) and enhancing the ecological stability of oasis. In order to assess the effects of revegetated plant communities, 21-year-old Haloxylon ammodendron shrubland (Shrubland), 28-year-old Populus simonii Carr. land (Poplar land) and 33-year-old Pinus sylvestris var. mongolica Litv land (Pine land) were selected as study objects.

Assessing the Effectiveness of Land Restoration Interventions in Dry Lands by Multitemporal Remote Sensing – A Case Study in Ouled DLIM (Marrakech, Morocco)

Journal Articles & Books
december, 2015
Morocco
Northern Africa

Atriplex nummularia has been extensively planted in Northern Africa to combat desertification. However, few studies evaluated the effectiveness of these interventions. This study aimed at assessing the dynamic performance of a number of Atriplex plantations located in the Marrakech province in terms of multitemporal dry biomass production. Three SPOT 5 images (2004, 2008 and 2012) and field biomass measurements were integrated to quantify the dry biomass production dynamics of plantations established from 1996 to 2007. Different plant ages covered the whole plant life cycle curve.

Spatial Distribution Patterns and the Evolution Process of Carbon Storage in a Typical Karst Canyon Area

Journal Articles & Books
december, 2015
China

Qinglong County in Guizhou, China is a typical karst canyon area. Using quadrat methods and a land use transfer matrix we studied the carbon storage spatial distribution pattern and evolution process over three independent periods (1988, 1999 and 2009) in this area. Based on the results we estimated the carbon pool capacity of the entire karst canyon area in Guizhou and contribution ratios. Carbon storage and average carbon density of the karst area in Qinglong decreased at first, and then increased over the sampling period.

Spatio‐Temporal Patterns of Land Use/Cover Changes Over the Past 20 Years in the Middle Reaches of the Tarim River, Xinjiang, China

Journal Articles & Books
december, 2015
China

The interaction between land use/cover change and landscape pattern is pivotal in research concerning global environmental change. This study uses three different Landsat images of 1989, 1998 and 2009 to study the land use/cover and landscape pattern changes in the middle reaches of the Tarim River basin. envi®, erdas®, ArcGIS® and fragstats® software were used to analyse the land use/cover changes. The objectives of study were to map and study the changes in land use/cover and landscape pattern, and propose some possible factors in making the land use/cover changes from 1989 to 2009.

Carbon Accumulation in the Bulk Soil and Different Soil Fractions During the Rehabilitation of Desertified Grassland in Horqin Sandy Land (Northern China)

Journal Articles & Books
december, 2015
China

Desertification, which affects more than two-thirds of the world's arid and semi-arid regions, is a significant global ecological and environmental problem. There is a strong link between desertification of the drylands and emission of CO₂ from soil and vegetation to the atmosphere. The Horqin Sandy Land is a severely desertified area in China's agro-pastoral ecotone due to its fragile ecology, combined with unsustainable land management.

Effects of salinity and drought on early seedling growth and survival of Artemisia herba-alba

Journal Articles & Books
december, 2015

Seedlings of Artemisia herba-alba grown in glasshouse were watered with differing salinities (0, 150, 250 or 350 mM NaCl) and watering frequencies of 3, 7, 14 or 21 days for a period of 6 weeks. At the end of the study, plant survival, dry matter yield, biomass allocation (shoot and root), leaf area, relative growth rate (RGR), net assimilation rate (NAR), specific leaf area (SLA) and leaf area ratio (LAR) were recorded. When watered with 0 mM NaCl, Artemisia herba-alba plants had similar (P> 0.9) final dry matter weight and 100% survival regardless of watering frequency.

Paraiba State, Brazil

december, 2015

This report is comprised of two volumes:
(i) volume one: risk assessment; and (ii) volume two: risk
management strategy. Volume one continues with chapter one,
which characterizes the recent performance of the
agriculture sector, including agro-climatic and market
conditions. It also identifies the productive systems used
for this analysis. Chapter two describes the main risks in
the agricultural sector, capturing market, production, and