The Spanish Dehesas: A financial appraisal of holm oak (Quercus ilex) regeneration

En España existen 2,25 millones de hectáreas de dehesas arboladas que se destinan a la producción de recursos de pastoreo para la ganadería, las especies cinegéticas, la producción de leña y de carbón. También proveen un hábitat para la vida salvaje, valores estéticos y recreativos, y son consideradas como zonas de excepcional interés ornitológico. Sin embargo, en lo últimos años con el objetivo de aumentar la rentabilidad de estas tierras, los agricultores han incrementado la carga ganadera respondiendo a los estímulos de las subvenciones públicas. La preocupación por la escasa regeneración natural de la dehesa de encinas ha conducido recientemente a estudiar incentivos para contrarrestar la amenaza que representan el sobrepastoreo del ganado doméstico sobre las poblaciones de encinas. Se construye aquí un modelo bioeconómico basado en cuatro estudios de casos realizados en la comarca de Monfragüe y su entorno (Extremadura). El modelo es usado para definir límites de pastoreo, acordes con la sustentabilidad de la encina a largo plazo. Los resultados indican que los agricultores con regímenes de pastoreo trashumantes altamente intensivos (mayores de 2,0 ovino equivalente/ha) generan impactos negativos sobre la regeneración natural de las encinas. Sin embargo, los resultados también muestran que es poco probable que los agricultores, con sistemas de manejo trashumantes moderadamente intensivos (menores de 1,5 ovino equivalente /ha), conduzcan a la desaparición de la encina. El modelo también se usa para determinar los cambios en las rentas agrícolas generados por restricciones potenciales en las estrategias de la gestión ganadera, para cumplir los límites de pastoreo. Esta información es utilizada para estimar las posibles compensaciones a los agricultores, por proveer servicios ambientales asociados con el hábitat de la encina. Estos resultados pueden ser empleados para orientar las prácticas de conservación y contribuir al desarrollo de políticas agro-ambientales, asociadas a los agro-ecosistemas de dehesa

Common Property Resource Management and REPS Uptake in Ireland: the case of Irish Commonage

This paper looks at the factors determining REPS participation among commonage farmers in the West of Ireland and on the impact REPS has had on participating farmers¿ income and on their environmental practices and attitudes. The study reveals that sheep farmers are less likely to join REPS than cattle farmers and that being in receipt of other sources of State income acted as a deterrent to participation. REPS had a positive impact on participants¿ income and was most successful in changing farmer practices in a more environmentally benign direction, when doing so imposed no additional costs on the farmer. Environmental awareness among all farmers appears to be poor although REPS farmers display more appreciation of the degraded state of commonage than do non-REPS farmers. Farmers preference for a continuation of the status quo with respect to commonage management and a lack of discontent with respect to the distribution of past commonage rights points to the potential of building on a more co-operative approach to environmental management

A Kinetic Model for Simultaneous Saccharification and Fermentation of Avicel With Saccharomyces cerevisiae

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Cancer prevalence in 129 breast-ovarian cancer families tested for BRCA1 and BRCA2 mutations

BACKGROUND: Women who carry germline mutations in the breast-ovarian cancer susceptibility genes, BRCA1 and BRCA2, are at very high risk of developing breast and / or ovarian cancer. Both genes are tumour suppressor genes that protect all cells from deregulation, and there are reports of their involvement in other cancers that vary and seem to depend on the population investigated. It is therefore important to investigate the other associated cancers in different populations to assist with risk assessments. OBJECTIVES: To assess the cancer risk profile in BRCA-mutation-positive and negative South African breast-ovarian cancer families, mainly of Caucasian origin. DESIGN: Descriptive study in which the prevalence of all cancers in the pedigrees of BRCA1- and BRCA2-mutation-positive groups and a group of families without mutations in either gene were compared with the general population. RESULTS: As expected, female breast and ovarian cancer was significantly increased in all three groups. Furthermore, male breast cancer was significantly elevated in the BRCA2-positive and BRCA-negative groups. Stomach cancer prevalence was significantly elevated in the BRCA2-positive families compared with the general population. CONCLUSIONS: These results can be applied in estimation of cancer risks and may contribute to more comprehensive counselling of mutation-positive Caucasian breast and / or ovarian cancer families

Long-distance dispersal maximizes evolutionary potential during rapid geographic range expansion

Conventional wisdom predicts that sequential founder events will cause genetic diver- sity to erode in species with expanding geographic ranges, limiting evolutionary potential at the range margin. Here, we show that invasive European starlings ( Sturnus vulgaris ) in South Africa preserve genetic diversity during range expansion, possibly as a result of frequent long-distance dispersal events. We further show that unfavour- able environmental conditions trigger enhanced dispersal, as indicated by signatures of selection detected across the expanding range. This brings genetic variation to the expansion front, counterbalancing the cumulative effects of sequential founding events and optimizing standing genetic diversity and thus evolutionary potential at range margins during spread. Therefore, dispersal strategies should be highlighted as key determinants of the ecological and evolutionary performances of species in novel envi- ronments and in response to global environmental change

A review of evidence on the environmental impact of Ireland’s Rural Environment Protection Scheme (REPS)

peer-reviewedSince its inception in 1994, there has been strong demand for evidence of the environmental effectiveness of the Rural Environment Protection Scheme (REPS), which paid farmers in the Republic of Ireland over €3 billion by 2010. A variety of research projects have been undertaken that investigate the environmental effects of REPS through an examination of either specific environmental measures or specific geographical areas. A review of available publications confirmed the absence of a comprehensive, national-scale study of the environmental impacts of REPS. Because of this, there is insufficient evidence with which to judge the environmental effectiveness of the national-scale implementation of the whole scheme. For some specific measures, however, sufficient evidence is available to inform an objective assessment in some cases, and to help learn how to improve environmental effectiveness in most cases. The majority of the REPS payments are now dedicated toward biodiversity objectives. Thus, biodiversity measures and options should be a priority for any national-scale environmental assessment of the scheme. Such a study would help identify the environmental benefits of REPS, the specific elements of REPS that are performing adequately, and those elements that are in need of improvement. Given the considerable overlap between REPS measures and options and those included in the 2010 Agri-Environment Options Scheme (AEOS), assessment of REPS measures could also be used to inform the likely environmental performance of the AEOS