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21.
Tibor Hartel Nora Fagerholm Mario Torralba Ágnes Balázsi Tobias Plieninger 《Strength and Conditioning Journal》2018,71(5):536-544
Rangelands in Europe are imprinted by livestock production and embedded in mosaic landscapes of grasslands, croplands, woodlands, and settlements. They developed as social-ecological systems: People managed rangelands in order to maintain or enhance their ecosystem services, which in turn supported their well-being. The appreciation of ecosystem services provided by rangelands depends on the broad, socioeconomic aspirations and abilities of the managers and the capital available to achieve these aspirations. Here we propose four archetypical social-ecological system representations for European rangelands along the dimensions of socioeconomic aspirations (i.e., oriented toward conventional or sustainable production) and available financial capital (i.e., low or high) to employ farming technologies on rangelands. The four archetypes are aspiration misfit, pockets of sustainability, techno-dependence, and money dependent sustainability. We describe the landscape physiognomy, ecosystem service appreciation, and management-related synergies and trade-offs in ecosystem services supply related to each archetype and formulate a number of research questions to document and further understand them as social-ecological systems. We include the importance of urbanization, land grabbing, and institutional networks in shaping the social-ecological archetypes of rangelands and the relationship between our social-ecological archetypes and the resilience and transformability of rangelands. 相似文献
22.
Anther culture in the breeding process of winter wheat. I. Ability of 1B—-1R wheat-rye translocation forms for androgenesis 45 winter wheat varieties or F1 hybrids, F2 populations and lines with 1B—1R wheat-rye translocation were tested for their anther culture ability. A total of 48058 anthers was cultured on Potato-2 medium. When averaged over all genotypes and the two experimental years frequencies of embryoid formation of 5.4—6.8 per 100 anthers were observed. Plant regeneration efficiency from embryoids ranged from 5.3—9.1 % or a mean of 4—5 green plants per 1000 anthers plated. The results confirmed the preferential regeneration frequency of gametes with the 1BL—1RS chromosome compared to the gametes with the 1BL—IBS chromosome. Multiple peroxidase were used as marker. The effect of cold pretreatment or of media on the androgenetic response and productivity was not important. On the contrary the variability between the anther response from single ears of the same genotype was noticeable. Examples are presented for the transferability of the androgenetic ability to breeding material. Most green plants obtained were haploid or spontaneous doubled haploid. By cloning it was guaranteed, that progenies were obtained from most of the haploids after colchicine treatment. 相似文献
23.
Agricultural reform and infrastructural development are among the major drivers of biodiversity loss and landscape homogenization worldwide. Ponds and other small stagnant water bodies are crucial for maintaining regional biodiversity, yet they are vulnerable to human induced landscape change. We investigated for 199 ponds in the ‘département’ Pas-de-Calais in north-western France if pond persistence (n = 86, 43%) or disappearance (n = 113, 57%) was related to wider changes in the landscape, over the period 1975–2006. Landscape data were obtained from aerial photographs (1963), two ASTER satellite images (2001 and 2003) and observations on the ground (1975 and 2006) and land use around the ponds was described over concentric circles with five different radii in the 100–1000 m range. Overall, pond disappearance was associated with a decrease in grassland and an increase in arable fields around the ponds. We found that the small, man-made cattle ponds, with either natural substrate or concrete drinking troughs, were more often affected than the larger, semi-natural ponds. Since the cattle ponds are regularly used for amphibian reproduction, their massive abandonment therewith weakens the population network and puts the local occurrence of some of the rarer species at risk. Spatial extrapolation of models on pond persistence allowed the identification of areas most at risk of further pond loss. We suggest that local amphibian conservation efforts will be the most effective if the focus is on the marshes and dune areas and on pond preservation in the remaining grasslands. 相似文献