285 research outputs found
Estimating optimal conservation in agricultural landscapes when costs and benefits of conservation measures are heterogeneous in space and over time
Designing agri-environmental schemes targeted at conservation poses the key question of how many financial resources should be allocated to address a particular aim such as the conservation of an endangered species. Economists can contribute to an answer by estimating the 'optimal level of species conservation'. This requires an assessment of the supply and the demand curve for conservation and a comparison of the two curves to identify the optimal conservation level. In a case study we estimate the optimal conservation level of Large Blue butterflies (protected by the EU Habitats Directive) in the region of Landau, Germany. The difference to other studies estimating optimal conservation is that a problem is addressed where costs and benefits of conservation measures are heterogeneous in space and over time. In our case study we find a corner solution where the highest proposed level of butterfly conservation is optimal. Although our results are specific to the area and species studied, the methodology is generally applicable to estimate how many financial resources should be allocated to conserve an endangered species in the context of agri-environmental schemes. --agri-environmental policy,biodiversity,optimal conservation,spatial heterogeneity,willingness-to-pay
A model-based approach for designing cost-effective compensation payments for conservation of endangered species in real landscapes
An approach is present which integrates an economic and an ecological model for designing cost-effective compensation payments for conservation of endangered species in real landscapes. The approach is used to develop a cost-effective compensation payment scheme for conservation of an endangered butterfly species (Maculinea teleius) protected by the EU Habitats Directive in the region of Landau, Germany. The economic model determines the costs of relevant conservation measures mowing meadows at different times and frequencies - and the ecological model quantifies the effects of these mowing regimes on the butterfly population. By comparing the ecological effects of different mowing regimes, the cost-effective regime and the corresponding payments are determined as a function of the conservation budget. The results of the case study are used to analyse the effect of metapopulation dynamics on the cost-effectiveness of compensation payment schemes, to evaluate an existing scheme in the region of Landau and to draw conclusions for the institutional design of payment schemes. --Conservation,biodiversity,metapopulation,cost-effectiveness,ecological-economic modelling
Disentangling values in the interrelations between cultural ecosystem services and landscape conservation : a case study of the Ifugao rice terraces in the Philippines
In the past few years, there has been a growing amount of research on economic quantifications and valuations of ecosystem services (ES) in agricultural systems. However, little attention has been given to cultural ESs (CES) in general and their link to the landscape in particular. This paper tries to tackle this gap with a case study on the Ifugao Rice Terraces of the Philippines. The study aims to understand the interrelations between the different CESs and their relationships with the landscape. Besides contributing to knowledge about the degradation of the rice terraces, this study was conducted in order to discuss at a theoretical level how CESs and their relationship with the landscape must be addressed in ES management and policy decisions. The methodological approach includes a combination of semistructured interviews (n = 60) and a perception survey (n = 66). The results reveal that CESs, apart from being interrelated, are also responsible for and affected by the degradation of the rice terraces, which is why they are important factors to consider
Morphology of caterpillars and pupae of European Maculinea species (Lepidoptera: Lycaenidae) with an identification table
Ofthe four recognized Maculinea species that occur in Europe, three (M. teleius, M. nausitlzous, and M. alcon) are found on damp meadows, and may co-occur; sometimes their larval instars even occupy the same host ant nest. It is, therefore, important to be able to distinguish between the caterpillars of these species for effective conservation. We present the morphology of the larvae and pupae of these three species, and a simple key to their identification. Inter-specific differences among larvae and pupae, and within-species differences among larval instars, are underlined in order to enable their proper identification. The length, colour and distribution of bristles are considered the best features for species and instar identification. The morphology ofthe described species is compared with that of the other European species, M. arion
CR1 clade of non-LTR retrotransposons from Maculinea butterflies (Lepidoptera: Lycaenidae): evidence for recent horizontal transmission
<p>Abstract</p> <p>Background</p> <p>Non-long terminal repeat (non-LTR) retrotransposons are mobile genetic elements that propagate themselves by reverse transcription of an RNA intermediate. Non-LTR retrotransposons are known to evolve mainly via vertical transmission and random loss. Horizontal transmission is believed to be a very rare event in non-LTR retrotransposons. Our knowledge of distribution and diversity of insect non-LTR retrotransposons is limited to a few species – mainly model organisms such as dipteran genera <it>Drosophila</it>, <it>Anopheles</it>, and <it>Aedes</it>. However, diversity of non-LTR retroelements in arthropods seems to be much richer. The present study extends the analysis of non-LTR retroelements to CR1 clade from four butterfly species of genus <it>Maculinea </it>(Lepidoptera: Lycaenidae).</p> <p>The lycaenid genus <it>Maculinea</it>, the object of interest for evolutionary biologists and also a model group for European biodiversity studies, possesses a unique, specialized myrmecophilous lifestyle at larval stage. Their caterpillars, after three weeks of phytophagous life on specific food plants drop to the ground where they are adopted to the ant nest by <it>Myrmica </it>foraging workers.</p> <p>Results</p> <p>We found that the genome of <it>Maculinea </it>butterflies contains multiple CR1 lineages of non-LTR retrotransposons, including those from MacCR1A, MacCR1B and T1Q families. A comparative analysis of RT nucleotide sequences demonstrated an extremely high similarity among elements both in interspecific and intraspecific comparisons. CR1A-like elements were found only in family Lycaenidae. In contrast, MacCR1B lineage clones were extremely similar to CR1B non-LTR retrotransposons from Bombycidae moths: silkworm <it>Bombyx mori </it>and <it>Oberthueria caeca</it>.</p> <p>Conclusion</p> <p>The degree of coding sequence similarity of the studied elements, their discontinuous distribution, and results of divergence-versus-age analysis make it highly unlikely that these sequences diverged at the same time as their host taxa. The only reasonable alternative explanation is horizontal transfer. In addition, phylogenetic markers for population analysis of <it>Maculinea </it>could be developed based on the described non-LTR retrotransposons.</p
- …