N. Wrage

Feeding goats on scrubby Mexican rangeland and pasteurization: influences on milk and artisan cheese quality.

The objective of this study was to evaluate the effect of foraging on local scrubby rangeland versus stable feeding with high-protein concentrate as well as the compulsory pasteurization process on goats’ milk and artisan soft cheese quality in terms of chemical composition and fatty acid profile. The results indicated that there were no significant differences in the energy, fat, or ash content of milk and cheese due to feeding; however, a significant influence of feeding on cheese protein and fatty acids in both milk and cheese was detected. Feeding on scrubby rangeland tended to increase the amounts of major polyunsaturated fatty acids in milk and cheese from goats. Pasteurization, which is mandatory in Mexico, did not alter the fatty acid concentrations in milk or cheese. Small goat-keepers using rangeland resources might claim better economical returns for products recognized as healthier. Further investigations to assure ecosystem sustainability of shrubby rangeland joined with economical evaluations and best animal management to avoid deleterious effects are recommended.

Phosphorus, Plant Biodiversity and Climate Change

Phosphorus (P) is a major plant nutrient. Its increasing use as a fertilizer has helped to raise crop and fodder production. However, the global reserves and resources of P are finite, demanding an efficient use of P. Under natural conditions, it is often in limited supply. Plants have developed adaptations to small soil P concentrations. Increased P levels can have unwanted side effects like eutrophication and algal blooms. Besides, P concentrations in the soil have often been found to be negatively correlated with plant diversity. For sustainable agriculture, it is essential to understand (1) adaptations of plants to small P concentrations in soils to maintain production with decreasing P reserves, (2) influences of P on phytodiversity to minimize unwanted effects, and (3) future developments of P and phytodiversity in relation to climate change to adjust agricultural practices.

Rangeland condition in relation to environmental variables, grazing intensity and livestock owners' perceptions in semi-arid rangeland in western Iran

Rangeland condition has often been assessed in relation to either botanical, edaphic, environmental or management factors. In this investigation, we analysed the interaction of soil and topographic variables, management and range condition against the background of a sociological survey of livestock owners in western Iran to better understand the main influencing factors of rangeland quality in the area. In four grazing areas in Kermanshah differing in grazing pressure, environmental variables and livestock owners’ perceptions on range condition, investigations of botanical composition, soil and topographic variables were carried out on 43 main plots. To evaluate range condition, four factors were considered, namely litter frequency, herbage palatability, amount of biomass, and percentage of bare soil. A questionnaire was used to obtain information about management practices, the perception of livestock owners on range condition and suggested solutions to problems in the different grazing areas. The range condition scores showed that the condition of the sites was either fair or poor. Of the soil and topographic factors, only north-facing aspect explained part of the variation in range condition scores. High grazing intensity was associated with poor range condition. To improve the rangeland condition, measures influencing water availability and a reduction of grazing pressure seem to be more relevant in the study area than fertilisation or seeding.