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As threats to biodiversity proliferate, establishment and expansion of protected areas have increasingly been advocated in recent decades. In establishing a network of protected areas, recurrent assessments of the biodiversity conservation actually afforded by these areas is required. Gap analysis has been useful to evaluate the sufficiency and performance of protected areas. We surveyed Reeves’s Pheasant Syrmaticus reevesii populations in 2018–2019 across its distribution range in central China to quantify the distribution of habitat suitable for this species. Our goal was to ascertain the current distribution of Reeves’s Pheasant and then identify the gaps in protecting Reeves’s Pheasant of the existing national nature reserve (NNR) network to provide suggestions for improving the conservation of this important species. The existing NNR network encompassed only 17.0% of the habitat suitable for Reeves’s Pheasant. Based on the current distributions of both suitable habitat and NNRs for Reeves’s Pheasant, we suggest most currently unprotected areas comprised moderately suitable habitat for species and should be prioritized in the future. A multiple species approach using Reeves’s Pheasant as a flagship species should be considered to understand the extent of mismatch between the distributions of protected areas and suitable habitat to improve the management effectiveness of NNRs. This case study provides an example of how the development of a conservation reserve network may be based on species distribution and habitat assessments and is useful to conservation efforts in other regions and for other species.
The natural coastal wetlands of the East Asian-Australasian Flyway (EAAF) are disappearing at alarming rates, leading to rapid declines of many populations of waterbirds in the most species-rich flyway in the world. The identification and assessment of possible alternative habitats that may buffer the loss of natural wetlands should, therefore, be a priority for the conservation of migratory waterbirds using this flyway. Coastal saltpans are functional wetlands that support large numbers of waterbirds worldwide. The Nanpu Saltpans in the northern Bohai Bay of the Yellow Sea in China are one of the largest (290 km2) saltpan complexes in the world. In this paper, we document the value of the Nanpu Saltpans for supporting waterbirds. The surveys, carried out from 2013 to 2016, included waterbird counts in the saltpans (93 km2) at high and low tide and on the adjacent natural tidal flats (57 km2) at low tide. Of the 89 waterbird species recorded, 27 had maximum counts exceeding the 1% threshold value of estimated flyway populations. The maximum counts of waterbirds in northward migration and southward migration in the Nanpu Saltpans were 96,000 and 93,500, respectively, including both foraging and roosting birds; these figures do not account for turnover, so the total number of birds using the site is likely to be higher. The maximum counts on the adjacent tidal flats at low tide amounted to 73,000 and 20,000 waterbirds during northward and southward migration, respectively, and most of them were foraging birds. In the boreal winter, few birds fed in the saltpans, but several thousand fed on the tidal flats. Waterbirds used the inland ponds (2.0–18.0 km from the intertidal area) mainly for feeding both during low tide and high tide and used the nearshore ponds (0.3–4.3 km from the intertidal area) mainly for high-tide roosting. Some species, such as Black-tailed Godwit Limosa limosa, Marsh Sandpiper Tringa stagnatilis, Pied Avocet Recurvirostra avosetta, and Black-winged Stilt Himantopus himantopus, occurred mainly in the saltpans; other species preferred tidal flats, such as Red Knot Calidris canutus, Great Knot Calidris tenuirostris, Bar-tailed Godwit Limosa lapponica, Eurasian Curlew Numenius arquata, Relict Gull Larus relictus, and Grey Plover Pluvialis squatarola. This study clearly demonstrates the joint ecological function of the Nanpu Saltpan complex and adjacent tidal flats as a key staging area for waterbirds in the EAAF, and as such both urgently warrant protected status.
The current status and distribution of the Vulnerable Reeves's pheasant Syrmaticus reevesii, endemic to central China, is poorly known. To obtain updated information on its status we selected 89 candidate sites in six provinces and one municipality in central China and conducted interviews and field surveys from April 2011 to April 2012. Interviews demonstrated the pheasant has disappeared from 46% of the surveyed sites. Our results also revealed a population decline at 46 sites, including protected areas, although population densities in protected areas were higher than those in non-protected areas. Eighty-three, 26 and 20% of the surveyed sites had evidence of poaching, habitat loss and use of poison, respectively, which were the three major threats to this species. To ensure the long-term survival of Reeves's pheasant in China, protection and management need to be enforced in both protected and non-protected areas. We recommend that this species should be upgraded to a national first-level protected species in China and recategorized as Endangered on the IUCN Red List.
High strength aluminum (Al) alloys were prepared by rapid solidification method in the Al–Ni–La system. Microstructural characterizations show that all the investigated Al–Ni–La alloys are comprised of Al, rod-like Al3Ni, and blocky Al11La3 phases, of which the size and volume fraction are composition-dependent. The Al85.5Ni9.5La5 (at.%) alloy shows the finest microstructure, which contributes to the highest strength along with considerable plasticity. The experimental analysis and finite element simulation (FES) show that the distribution of the intermetallic phases greatly affects the mechanical properties of the alloys. The rod-like Al3Ni phase precipitated with the locally uniform direction prevents the propagation of cracks and benefits the plastic deformation, whereas the blocky Al11La3 phase exhibits the nature of brittleness and acts as the origin of the microcrack initiation. These findings suggest a new method to design high strength Al alloys.
Staging sites are vital for large-sized migratory cranes, which require high-protein food sources during migration. In this study, we used field surveys and faecal analysis to determine the migration patterns and dietary composition of the globally threatened Red-crowned Crane Grus japonensis population that migrates and stages at the Yellow River Delta Nature Reserve (YRDNR), Eastern China. Analysis of 135 faecal samples collected during the migration season in 2008, 2010 and 2011 showed that 78.8% of the faeces comprised > 90% dry mass of tidal mudflat crab Helice tientsinensis remains, suggesting that tidal mudflat crab was an important source of food for these Red-crowned Cranes. Smaller percentages of two other crab species (Eriocheir sinensis, Macrophthalmus dilatatum), fish remains, ragworms Hediste diversicolor and vegetation were also detected in the faecal samples. Consumption of tidal mudflat crabs was found to increase from autumn through to spring. Surveys of tidal mudflat crabs from YRDNR revealed that female crabs have significantly smaller body size (dry mass) but higher energy reserve ratio (ash-free dry mass per body mass) compared to males. Red-crowned Cranes fed predominantly on small and medium-sized female crabs, with a female to male ratio of 5:1 in the diet, compared with the 1:2 ratio of female to male crabs found within the coastal wetland crab population. Our findings suggest that tidal mudflat crabs represent a critical food source for the migratory Red-crowned Crane population in YRDNR, and future crane conservation strategies should encompass the necessary measures to conserve the tidal mudflat crab population at this staging site.
Anthropogenic conversion of natural wetlands into artificial wetland habitats has produced complex wetland landscapes worldwide. In this study we investigated the responses of migratory and wintering waterbirds to five artificial wetland habitats (aquaculture ponds, paddyfields, irrigation canals, open water reservoirs and saltpans) within a novel natural-artificial wetland landscape, Yellow River Delta (YRD), eastern China from October 2007 to May 2008. The results showed that almost all bird community indicators in the YRD natural wetlands were higher than those in adjacent artificial wetlands. Across the landscape, natural wetlands remained most important for all waterbird guilds, and more than 90% of waterbird populations were dependent on these habitats. Artificial wetlands mainly provided a secondary role, supporting about 70% of waterbird species (including six species that reached 1% of their global or biogeographical flyway populations), but with distinctive functional capacity for specific waterbird guilds in different artificial wetlands. The conservation value of artificial wetlands is often ephemeral, mainly during autumn, for specific migratory waterbirds and complements that of remaining areas of natural wetlands. Therefore, the utilisation patterns of artificial wetlands are highly temporal and the majority of species are dependent on areas of natural wetland. A comprehensive study of the inter-seasonal and inter-annual variations in these different habitats and dependence by the various guilds in the YRD is required to enable the true value of these habitats to be understood. We suggest that the conservation of artificial wetlands should not be at the expense of natural wetlands, which should remain the priority for wetland landscape management. Management to maintain the existing artificial wetlands for migrating and wintering water birds should target habitat features that are absent or limited in natural wetlands thus increasing the carrying capacity of the YRD landscape.
There were 2,541 nature reserves accounting for c. 15% of China's land territory by 2009. As nature reserves hold the majority of the country's wildlife they play a fundamental role in protecting the country's biodiversity. National policies relevant to nature reserves have had a positive effect on biodiversity although these policies are now facing increasing challenges. We reviewed the development of relevant policy and legislation and identify and assess challenges, using a questionnaire survey and personal interviews. The main challenges identified and assessed included lack of harmonization between government departments, between nature reserves and other protected area designations, and between nature reserves and local communities. In addition, recent transfers of responsibilities between government entities, potential impacts of forest tenure reforms, and issues surrounding natural resource use and ecotourism were identified. These obstacles could undermine the achievements of biodiversity conservation in China if they are not addressed soon. Given these findings, we make recommendations to guide future policy formulation in relation to nature reserve management and development.
The influence of casting temperatures on microstructures and mechanical properties of rapidly solidified Cu50Zr45.5Ti2.5Y2 alloy was investigated. With increasing casting temperatures, the amount of the crystalline phase decreases. At a high casting temperature, i.e., 1723 K, glass-forming ability (GFA) of the present alloy is enhanced. The results imply that adjusting the casting temperature could be used for designing the microstructures of bulk metallic glass matrix composite. Nanoindentation tests indicated that CuZr phases are slightly softer and can accommodate more plastic deformation than the amorphous matrix. Compression tests confirmed that this kind of second phase (CuZr) precipitated under lower casting temperatures helps to initiate multiple shear bands, resulting in a great improvement in mechanical properties of the samples. Our work indicates that casting temperatures have a great influence on GFA, microstructures, and mechanical properties of the rapidly solidified alloy, therefore controlling the casting temperature is crucial to the production of BMGs.
Many species of China's Galliformes live in forests and it is often difficult to assess populations of species in these habitats. Such assessments are becoming increasingly important because much of China's forest has been altered through logging and other forms of human activity. After describing and mapping habitat types, we assessed two commonly used methods for counting pheasants (transects and point counts at dawn) in the Xianshennongjia Mountains in the Three Gorges area of Hubei Province in east-central China. Four pheasant species were recorded: Golden Pheasant Chrysolophus pictus, Temminck's Tragopan Tragopan temmincki, Koklass Pucrasia macrolopha and Common (or Ring-necked) Pheasant Phasianus colchicus. Golden Pheasants were detected most often by calls heard during transects and Koklass were recorded mostly during point counts at dawn. Temminck's Tragopan was detected during transects (by sightings) and also by calls at dawn. The relatively few Common Pheasants that were detected were registered mainly during transects. Golden Pheasants were found at the lowest altitudes, closest to human habitation and both Temminck's Tragopan and Koklass lived in various forest types above this. Common Pheasant was found in meadows at higher altitudes. We conclude that the methods used can determine general habitat use, but that no one method is likely to prove sufficient to unravel the detailed pattern of habitat use across all four species. In particular, further study is required to assess the relative importance of different forest types to Golden Pheasant, Temminck's Tragopan and Koklass. It would appear that human impact on the forest has affected the distribution of the pheasant species. For example, Common Pheasant is now absent from low-lying areas and occurs at what appears to be an unusually high altitude in the study area.
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