The interaction between ecological and hydrological processes is particularly important in arid and semi-arid regions. Often the interaction between these processes is not completely understood and they are studied separately. We developed a grid-based computer model simulating the dynamics of the four most common vegetation types (perennial grass, annuals, dwarf shrubs and shrubs) and related hydrological processes in the region studied.

BACKGROUND: Pastoralism in the USA began coincidently with the initiation of profound ecological change resulting from colonization in the sixteenth century. Relationships between pastoralism and wildlife conservation in three different contexts of land tenure, environmental legacy, and geography are examined. RESULTS: On the federal rangelands of the Intermountain West, based on limited scientific information, wildlife policy has been interpreted to require separation of native bighorn sheep from livestock to prevent disease transmission.

The status of many invasive plant species that are also of high commercial value is contentious. Management of negative impacts depends on the support and co-operation of people who regard the species as an asset. For example, buffel grass (Cenchrus ciliaris) is highly prized by many pastoralists in Australia as an introduced pasture grass for livestock but it also has significant and deleterious environmental impacts. Identifying management strategies that minimise environmental impacts yet support production benefits is crucial for achieving sustainable outcomes.

Recent studies using low-resolution satellite time series show that the Sahelian belt of West Africa is witnessing an increase in vegetation cover/biomass, called re-greening. However, detailed information on local processing and changes is rare or lacking. A multi-temporal set of Landsat images was used to produce land-cover maps for the years 2000 and 2007 in a semi-arid region of Niger, where an anomalous vegetation trend was previously detected.

Traditionally, management of rangelands is based on the successional theory for vegetation developed by Clements. This approach, which came to be known as “the range succession model”, assumes a progressive change of vegetation towards the final (climax) stage and considers grazing as a primary driver of its dynamics. This model cannot be applied in Mediterranean rangelands, however, because they are largely modified plant communities and their final stage is usually a forest or dense woodland.

Rangelands encompass 30-40% of Earth's land surface and support 1-2 billion people. Their predominant use is extensive livestock production by pastoralists and ranchers. But rangelands are characterized by ecological, economic, and political marginality, and higher-value, more intensive land uses are impinging on rangelands around the world. Earth Stewardship of rangelands must address both livestock management and the broader socioecological dynamics that promote land-use changes, fragmentation, and degradation.

Establishment of seasonal grazing enclosures has become an important rangeland rehabilitation strategy in semi-arid regions. This study assessed the impact of enclosure age and enclosure management on the vegetation composition in the Njemps Flats range unit, Lake Baringo Basin (Kenya). Six communal enclosures (13-23 years since establishment) and six private enclosures (3-17 years since establishment) were selected.

Dzud is the Mongolian term for a winter weather disaster in which deep snow, severe cold, or other conditions render forage unavailable or inaccessible and lead to high livestock mortality. Dzud is a regular occurrence in Mongolia, and plays an important role in regulating livestock populations. However, dzud, especially when combined with other environmental or socio-economic stresses and changes, can have a significant impact on household well-being as well as local and national economies.

In the future scenario for livestock development, there is a continuing role for smallholder producers, particular for dairy and small ruminants, relying heavily on grass and crop-residues, however in a growth mode, intensifying production, and enhancing the efficiency of resource use (less land, labor and feed resources per unit product). In particular improving the efficiency of converting feed into milk and meat will be critical to increase their income.

Reforestation measures for degraded lands, strategies for the sustainable management of forest resources, and agroforestry practices that incorporate trees into farming systems are increasingly demonstrating their promise for producing commercialized tree products. Although the level of investment so far has remained modest, the challenge is to find ways to scale up promising investments in a way that will have a clear impact at the landscape level.