826 research outputs found
Genetic erosion in the snail <i>Littoraria subvittata</i> (Reid, 1986) due to mangrove deforestation
In tropical coastal ecosystems mangrove forests are important as feeding, spawning, breeding and nursery grounds for many marine species. High human population pressure in coastal areas has led to the loss and deterioration of mangrove habitats. Solar salt production can affect these habitats along the East African coast. Littorinid snails live on mangrove trees, forming an important component of the mangrove ecosystem and have been used as bioindicators of environmental health and community stress. Littoraria subvittata is the most abundant littorinid species in mangroves along the East African coast. Partial mitochondrial cytochrome oxidase subunit 1 (COI) gene sequences of 298 individuals were used to assess the impact of mangrove deforestation at salt ponds on the genetic diversity and structuring of L. subvittata populations, as well as to infer the demographic history of the species. Nucleotide and haplotype diversities were found to be lower in samples from mangroves at salt ponds than in samples from natural mangroves. The mean nucleotide diversity was 0.049 ± 0.036% and 0.115 ± 0.068% in mangroves at salt ponds and natural mangroves, respectively. The mean haplotype diversity was 0.23 ± 0.14 and 0.50 ± 0.14 in mangroves at salt ponds and natural mangroves, respectively. Analysis of molecular variance (AMOVA) detected a significant population structure (Đ€st = 0.049; P ct = 0.022; P st = 0.054, P st = â0.0026, P = 0.64). Reduced effective population size was observed in most samples from mangrove sites at salt ponds compared with natural mangrove. The direction of migrants was mostly from salt ponds to natural mangroves. These results show that salt ponds have a negative impact on the genetic diversity of L. subvittata populations and modify the population's genetic structure
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Unraveling the "passion orchestra" in academia
This paper disentangles how organization members' âpassion orchestraâ is related to their entrepreneurial intentions in the particularly relevant context of academia. Drawing on passion literature and identity theory, we propose and test a model linking two central parts of researchers' âpassion orchestraâ, namely entrepreneurial and obsessive scientific passion, directly and indirectly, to spin-off and start-up intentions. While spin-off intentions refer to intentions to found a firm based upon research results, start-up intentions denote intentions to start any type of company. Using a sample of 2308 researchers from 24 European universities, our findings reveal that higher levels of entrepreneurial passion are associated with both stronger spin-off and start-up intentions. Further, obsessive scientific passion is positively associated with researchers' intentions to create a spin-off, and negatively with their propensity to establish a start-up. Entrepreneurial self-efficacy and affective organizational commitment mediate these effects. Finally, the two types of passion show characteristic interactions. Obsessive scientific passion moderates the entrepreneurial passionâintentions relationship such that it strengthens spin-off intentions. Our results highlight that recasting the individual driven by a singular passion to one with a âpassion orchestraâ provides a more holistic understanding of the new venture creation process. Implications for research and practice are discussed
Ecological health of coral reefs in Zanzibar
Coral reefs are important ecosystems in terms of their biodiversity and ecosystem functions. Particularly at local scales, coral reefs are vulnerable to natural and anthropogenic disturbances, leading to the degradation of reef health. Here, we employed two different methods to monitor reef health. First, we conducted line transect surveys to record the benthic community structure to infer ecological reef health. Secondly, trace metal concentrations in sediment samples and a bioindicator sponge species, Haliclona fascigera, were compared among sites to detect cryptic degradation and unknown sources of pollution. The study area comprised six reefs situated along the coast of Zanzibarâs main agglomeration, Stone Town, and subject to different types of disturbances and conservation management schemes. Overall, coral reef health was found to decrease with increasing proximity to Stone Town, with living hard coral cover being particularly low on reefs closest to Stone Town, which coincided with greater fishing, tourism, and pollution pressures. Reef assessments based on trace metal analyses differed from the community structure surveys. All sites showed high levels of arsenic and cadmium contamination, with some samples revealing concerning levels of chromium, copper and zinc. The reefs differed significantly between each other in terms of trace metal concentration for both sediments (p = 0.031, PERMANOVA) and sponge samples (p = 0.001, PERMANOVA). Trace metal concentrations were not correlated with distance to Stone Town, highlighting the downstream effects of industrial and urban sewage on even remote reefs. Coral reef health assessment was found to be dependent on the survey method employed, which is why we recommend the combination of complementary methods
Timing and mechanism of the rise of the Shillong Plateau in the Himalayan foreland
The Shillong Plateau (northeastern India) constitutes the only significant topography in the Himalayan foreland. Knowledge of its surface uplift history is key to understanding topographic development and unraveling tectonicâclimateâtopographic coupling in the eastern Himalaya. We use the sedimentary record of the Himalayan foreland basin north of the Shillong Plateau to show that the paleo-Brahmaputra river was redirected north and west by the rising plateau at 5.2â4.9 Ma. We suggest that onset of plateau uplift is a result of increased fault-slip rates in response to stresses caused by the Indian lithosphere bending beneath the Himalaya
Towards sustainable European grassland farming with Inno4Grass: an infrastructure for innovation and knowledge sharing
peer-reviewedEuropean agriculture is facing tremendous challenges related to the rapid decrease in farm populations, competitiveness on open markets and the preservation of natural resources. Grasslands, which are highly significant for nature conservation often face land-use competition with arable cropping, urbanisation and other uses. Farmers need dedicated innovations to improve the economic performance of grasslands and their effective implementation in practice. This requires co-creation of knowledge between researchers and farmland practitioners, as was broadly pointed out by the European Commission. This paper describes a novel approach for creating a collaborative space for grassland innovations contributing to profitability of European grassland farms while preserving environmental benefits. Innovative modes of collaboration between practice and science are enabled by an international thematic network across eight European member states. A methodology that serves to collect farmersâ innovative ideas and to stimulate collaboration among various stakeholders (farmersâ groups, extension services, education and research) including cross-border collaborations, where grassland-related knowledge is made available for local conditions. This interactive innovation model fosters knowledge exchange and establishes a farmland-specific information management system. The aim is to stimulate a renewed, collaborative innovation culture for European Union (EU) grasslands. The methods are conceptualised and put into practice by the thematic network project Inno4Grass funded under Horizon 2020
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