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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.

Land use, rangeland degradation and ecological changes in the southern Kalahari, Botswana

Journal Articles & Books
Dezembro, 2016
Botswana

Dual‐scale analyses assessing farm‐scale patterns of ecological change and landscape‐scale patterns of change in vegetation cover and animal distribution are presented from ecological transect studies away from waterpoints, regional remotely sensed analysis of vegetation cover and animal numbers across the southern Kalahari, Botswana. Bush encroachment is prevalent in semi‐arid sites where Acacia mellifera Benth. is widespread in communal areas and private ranches, showing that land tenure changes over the last 40 years have not avoided rangeland degradation.

Identifying challenges to enforcement in protected areas: empirical insights from 15 Colombian parks

Journal Articles & Books
Dezembro, 2016

Protected areas are intended to conserve biodiversity by restricting human activities within their boundaries. However, such restrictions are difficult to enforce fully in many tropical parks. Improving regulatory enforcement requires an understanding of prevailing challenges to detection and sanctioning activities. Drawing from empirical field research in 15 Colombian parks, I show that current enforcement efforts may be insufficient to deter most priority threats.

Farmers’ Perceptions and Satisfaction Levels on the Performance of Watershed Development Activities in the Morni Hill area of the Siwalik Himalayas in India

Journal Articles & Books
Dezembro, 2016
Índia

We describe the results of a survey of farmers’ perceptions of and satisfaction with the performance of watershed development activities on socioeconomic, agriculture and livestock, and environmental attributes. We administered a questionnaire to 120 farmers randomly interviewed in the Morni Hill area of the Siwalik Himalayas in India. Our results show that the farmers have considerable knowledge about the implementation of watershed development activities and their impact on the economy, agriculture and the environment.

Rangeland responses to pastoralists’ grazing management on a Tibetan steppe grassland, Qinghai Province, China

Journal Articles & Books
Dezembro, 2016
China
Ásia

Livestock grazing is the principal land use in arid central Asia, and range degradation is considered a serious problem within much of the high-elevation region of western China termed the Qinghai-Tibetan Plateau (QTP). Rangeland degradation on the QTP is variously attributed to poor livestock management, historical-cultural factors, changing land tenure arrangements or socioeconomic systems, climate change, and damage from small mammals. Few studies have examined currently managed pastures using detailed data capable of isolating fine-scale livestock–vegetation interactions.

Analysis of GPS trajectories to assess spatio-temporal differences in grazing patterns and land use preferences of domestic livestock in southwestern Madagascar

Journal Articles & Books
Dezembro, 2016
Madagáscar

In order to investigate spatial and temporal characteristics of the purely grazing-based livestock husbandry system in southwestern Madagascar, individual animals from 12 cattle and 12 goat herds that were equally distributed across four villages were fitted with GPS tracking collars and their behaviour during pasturing was directly observed to identify seasonal variations in land use and movement patterns along the regional altitude and vegetation gradient.

Defoliation of marandu grass and effects on leaf area index and number of apical meristems

Journal Articles & Books
Dezembro, 2016

The objective of this study was to understand how the strategy of defoliation prior to deferred grazing modifies the structure of Brachiaria brizantha cv. marandu (marandu grass) at the beginning of deferment. The following three defoliation strategies wer e evaluated: 15/15 cm – canopy height of 15 cm in the three months prior to deferment
30/15 cm – canopy height of 30 cm in the preceding three months and defoliation to 15 cm at the beginning of deferment

Can ecological land classification increase the utility of vegetation monitoring data?

Journal Articles & Books
Dezembro, 2016
Estados Unidos

Vegetation dynamics in rangelands and other ecosystems are known to be mediated by topoedaphic properties. Vegetation monitoring programs, however, often do not consider the impact of soils and other sources of landscape heterogeneity on the temporal patterns observed. Ecological sites (ES) comprise a land classification system based on soil, topographic, and climate variations that can be readily applied by land managers to classify topoedaphic properties at monitoring locations.

Effect of land-use conversion on ecosystem C stock and distribution in subtropical grazing lands

Journal Articles & Books
Dezembro, 2016

BACKGROUND AND AIMS: Grazing lands worldwide are increasingly subjected to intensification to meet global demand for food; however, management practices intended to increase production can also affect ecosystem carbon (C) stocks. This study evaluated long-term (>22 years) ecosystem C responses to conversion of native grazing lands into more intensively managed silvopasture and sown pastures. METHODS: Above- and below-ground C pools in each land use type were evaluated.

effects of disturbance on the population structure and regeneration potential of five dominant woody species – in Hugumburda‐Gratkhassu National Forest Priority Area, North‐eastern Ethiopia

Journal Articles & Books
Dezembro, 2016
Etiópia

Vast areas of forests in North‐eastern Ethiopia have been replaced by cropland, shrub land or grazing areas. Thus, information about how vegetation composition and structure varies with disturbance is fundamental to conservation of such areas. This study aimed to investigate the effects of disturbance on the population structure and regeneration potential of five dominant woody species within forest where local communities harvest wood and graze livestock. Vegetation structure and environmental variables were assessed in 50 quadrats (20 m × 20 m).

Herbicide Control Strategies for Ventenata dubia in the Intermountain Pacific Northwest

Journal Articles & Books
Dezembro, 2016

Ventenata dubia is an exotic annual grass that has become increasingly invasive in various perennial grass systems throughout the Intermountain Pacific Northwest. Currently, little information is available to landowners about herbicide control options. In our first field study, we evaluated V. dubia control efficacy and perennial grass tolerance of herbicides applied pre-emergence (PRE) at two locations and as an early postemergence (EPOST) application at four different conservation reserve grasslands, with each grassland dominated by different perennial grass species.

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.