Beyond Site-Specific Criteria: Conservation of Migratory Birds and Their Habitats from a Network Perspective

Many populations of birds depend on networks of sites to survive. Sufficient connectivity that allows movement between the sites throughout the year is a critical requirement. We found that existing international frameworks and policies for identifying sites important for bird conservation focus more at the level of the individual site than on the site network and its connectivity. Only 21% of site criteria acknowledge the importance of movement networks for birds, and such network criteria were mostly (67%) qualitative. We suggest a three-step quantitative approach for informing conservation about the connectivity of bird movements (especially when migrating) from a network perspective, by reviewing current scientific knowledge. The first step is to construct a bird movement network by identifying sites frequently used by birds as ‘nodes’, and then define ‘edges’ from the probability of non-stop flight between each pair of nodes. The second step is to quantify network connectivity, i.e., the extent to which the site network facilitates bird movements. The last step is to assess the importance of each site from its contribution to network connectivity. This approach can serve as a tool for comprehensive and dynamic monitoring of the robustness of site networks during global change

Beyond Site-Specific Criteria: Conservation of Migratory Birds and Their Habitats from a Network Perspective

Many populations of birds depend on networks of sites to survive. Sufficient connectivity that allows movement between the sites throughout the year is a critical requirement. We found that existing international frameworks and policies for identifying sites important for bird conservation focus more at the level of the individual site than on the site network and its connectivity. Only 21% of site criteria acknowledge the importance of movement networks for birds, and such network criteria were mostly (67%) qualitative. We suggest a three-step quantitative approach for informing conservation about the connectivity of bird movements (especially when migrating) from a network perspective, by reviewing current scientific knowledge. The first step is to construct a bird movement network by identifying sites frequently used by birds as ‘nodes’, and then define ‘edges’ from the probability of non-stop flight between each pair of nodes. The second step is to quantify network connectivity, i.e., the extent to which the site network facilitates bird movements. The last step is to assess the importance of each site from its contribution to network connectivity. This approach can serve as a tool for comprehensive and dynamic monitoring of the robustness of site networks during global change

Synthesis, Characterization and Photoelectric Properties of Fe2O3 Incorporated TiO2 Photocatalyst Nanocomposites

In the present work we report the sol-gel synthesis of pure TiO2 and (TiO2)1−x(Fe2O3)x nanocomposites with different Fe2O3 contents (x = 0, 0.1, 0.5, and 1.0 for pure TiO2, Fe2O3 incorporated 0.1, 0.5, and pure Fe2O3 which are denoted as PT, 0.1F, 0.5F, and PF, respectively). The structural, morphological, optical, and surface texture of the prepared nanocomposites were characterized using various techniques. The structural studies confirm the strong influence of Fe2O3 contents on the crystallite sizes and dislocation values. The size of the crystallites was increased by the increase in Fe2O3 contents. The bandgap values elucidated from DRS analysis were decreased from 3.15 eV to 1.91 eV with increasing Fe2O3 contents. The N2-Physorption analysis has confirmed the mesoporous nature of the samples with a comparable specific surface area of 35 m2/g. The photoelectrochemical measurements (CV, CA and EIS) were performed to assess the photoelectric properties of the prepared materials. It was found that the PT samples have the highest catalytic activity and photocurrent response compared to other composites. The reduction in current density was as follows: 2.8, 1.65, 1.5 and 0.9 mA/cm2, while the photocurrent response was ca. 800, 450, 45, 35 µA/cm2 for PT, 0.1F, 0.5F and PF samples, respectively. The EIS results showed that the (TiO2)1−x(Fe2O3)x nanocomposites exhibit lower charge transfer resistance than pure titania and hematite samples