9 research outputs found

    Evaluating staging habitat quality to advance the conservation of a declining migratory shorebird, Red Knot <i>Calidris canutus</i>

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    Identifying where and when population ‘bottlenecks’ occur is critical to the conservation of migratory species, many of which are declining precipitously worldwide. Especially challenging is the evaluation of changes to staging sites. These sites are indispensable links in the migratory cycle but are typically used only briefly. We devised a field-based approach to assess the quality and carrying capacity of a critical staging site in Nanpu, China, for the declining, migratory Red Knot (Calidris canutus rogersi &amp; C. c. piersmai) during northward migration. The Nanpu tidal flat supports 50,000–100,000 Red Knots annually, and while there, the knots feed almost exclusively on the bivalve Potamocorbula laevis. We simultaneously monitored changes in the abundance of Red Knots and bivalves across this entire staging site in spring 2018. After taking into account potential competition with other shorebird species, we estimated that the Nanpu tidal flat was capable of supporting approximately 1.46–1.70 times the observed level of Red Knot usage of this site, and therefore is operating below, but close to, carrying capacity with respect to food resources for Red Knots. This result suggests that any further habitat loss or degradation at this site could harm the Red Knot population along the entire East Asian-Australasian Flyway. Synthesis and applications. Quantitative monitoring and evaluation of habitat quality of staging sites are essential to successfully conserve declining migratory species. In particular, researchers and conservation practitioners should incorporate both population size and staging duration to more accurately assess the importance of different sites and to quantify how changes in staging habitat quality may translate into changes in the population sizes of migratory species at both local and global scales.</p

    Ecological Environment Evaluation Based on Remote Sensing Ecological Index: A Case Study in East China over the Past 20 Years

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    East China is one of the most active regions in terms of economic and social development, and with the accelerated urbanization process, environmental problems are becoming increasingly prominent. The objective, quantitative, and timely evaluation of spatial and temporal changes in ecological quality is of great significance for environmental protection and decision making. The remote sensing ecological index (RSEI) is an objective, fast, and easy ecological quality monitoring and evaluation technique which has been widely used in the field of ecological research, but it often involves problems of cloud occlusion and stitching difficulties when used to conduct large-scale and long-term monitoring. In this paper, based on the Google Earth Engine (GEE) platform, an RSEI was constructed using MODIS data products to evaluate the spatial and temporal changes in ecological quality in East China over the past 20 years. The study shows the following: (1) The mean RSEI values in 2000, 2005, 2010, 2015, and 2020 were 0.67, 0.55, 0.59, 0.58, and 0.63, respectively, with the mean values first decreasing and then showing a stable increasing trend. In Shanghai and Jiangsu, the mean RSEI values show a fluctuating characteristic of &ldquo;falling and then rising&rdquo;, and large respective decreases of 32.4% and 25.8% throughout the monitoring period. The RSEI values in Fujian Province showed a relatively stable upward trend during the study period (19% increase). (2) The RSEI spatially correlated clustering maps of the local indicators showed that the regions with a high degree of clustering are mainly located in Quzhou City, Zhejiang Province, Ningde City, Fujian Province, and northern Anhui Province (Bozhou and Huabei). With the promotion of ecological civilization and the enhancement of environmental protection awareness, the vegetation cover has significantly increased, which has led to the rise in RSEI values. The low values are mainly distributed in densely populated areas with more human activity, such as the central-eastern part of Jiangsu Province, central Anhui Province, Shanghai, and northern Zhejiang Province. With the development of cities, impervious surfaces occupy more and more ecological land, which eventually affects the regional RSEI values. (3) This research provides a promising method for the evaluation of spatial and temporal changes in ecological environment quality based on an RSEI and GEE. The image processing, based on GEE cloud computing, can help overcome the problems of missing remote sensing data, chromatic aberrations, and spatial and temporal inconsistency, which could greatly improve the efficiency of image processing and extend the application of the remote sensing ecological index to large-scale, long-term ecological monitoring. The research results can provide a reference for improving the applicability and accuracy of remote sensing ecological indices and provide a theoretical basis for ecological conservation and land management in the context of rapid urbanization

    Ecological Environment Evaluation Based on Remote Sensing Ecological Index: A Case Study in East China over the Past 20 Years

    No full text
    East China is one of the most active regions in terms of economic and social development, and with the accelerated urbanization process, environmental problems are becoming increasingly prominent. The objective, quantitative, and timely evaluation of spatial and temporal changes in ecological quality is of great significance for environmental protection and decision making. The remote sensing ecological index (RSEI) is an objective, fast, and easy ecological quality monitoring and evaluation technique which has been widely used in the field of ecological research, but it often involves problems of cloud occlusion and stitching difficulties when used to conduct large-scale and long-term monitoring. In this paper, based on the Google Earth Engine (GEE) platform, an RSEI was constructed using MODIS data products to evaluate the spatial and temporal changes in ecological quality in East China over the past 20 years. The study shows the following: (1) The mean RSEI values in 2000, 2005, 2010, 2015, and 2020 were 0.67, 0.55, 0.59, 0.58, and 0.63, respectively, with the mean values first decreasing and then showing a stable increasing trend. In Shanghai and Jiangsu, the mean RSEI values show a fluctuating characteristic of “falling and then rising”, and large respective decreases of 32.4% and 25.8% throughout the monitoring period. The RSEI values in Fujian Province showed a relatively stable upward trend during the study period (19% increase). (2) The RSEI spatially correlated clustering maps of the local indicators showed that the regions with a high degree of clustering are mainly located in Quzhou City, Zhejiang Province, Ningde City, Fujian Province, and northern Anhui Province (Bozhou and Huabei). With the promotion of ecological civilization and the enhancement of environmental protection awareness, the vegetation cover has significantly increased, which has led to the rise in RSEI values. The low values are mainly distributed in densely populated areas with more human activity, such as the central-eastern part of Jiangsu Province, central Anhui Province, Shanghai, and northern Zhejiang Province. With the development of cities, impervious surfaces occupy more and more ecological land, which eventually affects the regional RSEI values. (3) This research provides a promising method for the evaluation of spatial and temporal changes in ecological environment quality based on an RSEI and GEE. The image processing, based on GEE cloud computing, can help overcome the problems of missing remote sensing data, chromatic aberrations, and spatial and temporal inconsistency, which could greatly improve the efficiency of image processing and extend the application of the remote sensing ecological index to large-scale, long-term ecological monitoring. The research results can provide a reference for improving the applicability and accuracy of remote sensing ecological indices and provide a theoretical basis for ecological conservation and land management in the context of rapid urbanization

    Foundation Research on Physicochemical Properties of Mine Insulation Materials

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    The known cooling methods for the high-temperature operating environment of a mine mainly include ventilation, refrigeration, heat insulation, and individual protection. Among them, the superior performance and wide application of the heat insulation materials have attracted the attention of the coal mining industry. In this paper, three types of mineral insulation materials were prepared using basalt fiber, glass fiber, vitrified microbeads in combination with cement, sand, high-strength ceramsite, water, etc. In addition, the thermal conductivity and compressive strength of the prepared specimens were assessed. The results show that the test specimen containing basalt fiber had a great thermal insulation effect and achieved the required compressive strength. Furthermore, according to the COMSOL simulation results, the test specimen containing basalt fiber had a better thermal insulation effect than the ordinary concrete materials. Therefore, the research results of this article have guiding significance to search for new mine thermal insulation materials

    Evaluating staging habitat quality to advance the conservation of a declining migratory shorebird, Red Knot <i>Calidris canutus</i>

    Get PDF
    Identifying where and when population ‘bottlenecks’ occur is critical to the conservation of migratory species, many of which are declining precipitously worldwide. Especially challenging is the evaluation of changes to staging sites. These sites are indispensable links in the migratory cycle but are typically used only briefly. We devised a field-based approach to assess the quality and carrying capacity of a critical staging site in Nanpu, China, for the declining, migratory Red Knot (Calidris canutus rogersi & C. c. piersmai) during northward migration. The Nanpu tidal flat supports 50,000–100,000 Red Knots annually, and while there, the knots feed almost exclusively on the bivalve Potamocorbula laevis. We simultaneously monitored changes in the abundance of Red Knots and bivalves across this entire staging site in spring 2018. After taking into account potential competition with other shorebird species, we estimated that the Nanpu tidal flat was capable of supporting approximately 1.46–1.70 times the observed level of Red Knot usage of this site, and therefore is operating below, but close to, carrying capacity with respect to food resources for Red Knots. This result suggests that any further habitat loss or degradation at this site could harm the Red Knot population along the entire East Asian-Australasian Flyway. Synthesis and applications. Quantitative monitoring and evaluation of habitat quality of staging sites are essential to successfully conserve declining migratory species. In particular, researchers and conservation practitioners should incorporate both population size and staging duration to more accurately assess the importance of different sites and to quantify how changes in staging habitat quality may translate into changes in the population sizes of migratory species at both local and global scales

    Data and code for Liang et al. Assessing shorebird mortalities due to razor clam aquaculture at key migratory stopover sites in southeastern China

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    &lt;p&gt;This repository contains codes and data for Liang et al.&nbsp;2023 Assessing shorebird mortalities due to razor clam aquaculture at key migratory stopover sites in southeastern China. Conservation Biology (doi/10.1111/cobi.14185). We provided data and code for estimating the mortalities of all shorebirds (and five individual species) entangled at two sites, including Yueqing Bay and Xinghua Bay, in southeastern China in April and May 2021.&nbsp;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Datasets:&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;"dat1_shorebird_mortality" contains two datasets: one with mortality counts for each net transect collected in April and May 2021, and another dataset collected at the same sites in April and May 2023. A new parameter was collected in 2023 to correct the mortality rate model (for more details, refer to the Methods section in Liang et al. 2023).&lt;/p&gt;&lt;p&gt;"dat2_net_transect" contains data on the area of the net transects monitored in March, April, and May.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;R scripts:&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;"mortality_allshorebirds" contains code for estimating the overall mortality of all shorebirds at the two sites during the two months (April and May).&lt;/p&gt;&lt;p&gt;"mortality_BLTG.r" contains code for estimating the mortality of Black-tailed Godwits at the two sites during the two months (April and May).&lt;/p&gt;&lt;p&gt;"mortality_TESP.r" contains code for estimating the mortality of Terek Sandpipers at the two sites during the two months (April and May).&lt;/p&gt;&lt;p&gt;"mortality_CORS.r" contains code for estimating the mortality of Common Redshanks at the two sites during the two months (April and May).&lt;/p&gt;&lt;p&gt;"mortality_CUSP.r" contains code for estimating the mortality of Curlew Sandpipers at the two sites during the two months (April and May).&lt;/p&gt;&lt;p&gt;"mortality_STSP.r" contains code for estimating the mortality of Sharp-tailed Sandpipers at the two sites during the two months (April and May).&lt;/p&gt;&lt;p&gt;"Summary_figure.r" contains code for plotting the mortality of all shorebirds (as shown in Figure 2 in the paper) and the five individual species (Figure 3).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Outputs:&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;In the "output_results" folder, you can find 1,000,000 draws of mortality estimates (100 models * 10,000 mortality estimates) for all shorebirds in the file "mortality_All_Shorebirds_oct23.rds," as well as separate files for the five individual species:&lt;/p&gt;&lt;p&gt;Black-tailed Godwit: "mortality_BLTG_oct23.rds"&lt;/p&gt;&lt;p&gt;Terek Sandpiper: "mortality_TESP_oct23.rds"&lt;/p&gt;&lt;p&gt;Common Redshank: "mortality_COSP_oct23.rds"&lt;/p&gt;&lt;p&gt;Curlew Sandpiper: "mortality_CUSP_oct23.rds"&lt;/p&gt;&lt;p&gt;Sharp-tailed Sandpiper: "mortality_STSP_oct23.rds"&lt;/p&gt

    Evaluation of Immunogenicity and Safety of Vero Cell-Derived Inactivated COVID-19 Vaccine in Older Patients with Hypertension and Diabetes Mellitus

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    Background: To evaluate the immunogenicity and safety of the COVID-19 vaccine (Vero cell), inactivated, in a population aged ≄60 years with hypertension or(/and) diabetes mellitus. Methods: A total of 1440 participants were enrolled and divided into four groups, 330 in the hypertension group, 330 in the diabetes group, 300 in the hypertensive combined with diabetes group (combined disease group), and 480 in the healthy population group. Two doses of the COVID-19 vaccine (Vero cell), inactivated, were administered at a 21-day interval and blood samples were collected before vaccination and 28 days after the second dose to evaluate the immunogenicity. The adverse events and changes in blood pressure and blood glucose levels after vaccination were recorded. Results: The seroconversion rate of the COVID-19 neutralizing antibodies was 100% for all participants. The post-inoculation geometric mean titer (GMT) in the four groups of the hypertension, diabetes, combined disease, and healthy populations were 73.41, 69.93, 73.84, and 74.86, respectively. The seroconversion rates and post-vaccination GMT in the hypertension, diabetes, and combined disease groups were non-inferior to the healthy population group. The rates of vaccine-related adverse reactions were 11.93%, 14.29%, 12.50%, and 9.38%, respectively. No serious adverse events were reported during the study. No apparent abnormal fluctuations in blood pressure and blood glucose values were observed after vaccination in participants with hypertension or(/and) diabetes. Conclusions: The COVID-19 vaccine (Vero cell), inactivated, showed good immunogenicity and safety in patients aged ≄60 years suffering from hypertension or(/and) diabetes mellitus

    Immunogenicity and Safety of an Inactivated Enterovirus 71 Vaccine Administered Simultaneously with Hepatitis B Virus Vaccine, Group A Meningococcal Polysaccharide Vaccine, Measles-Rubella Combined Vaccine and Japanese Encephalitis Vaccine: A Multi-Center, Randomized, Controlled Clinical Trial in China

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    Background: The aim of this study was to investigate the immunogenicity and safety of the enterovirus 71 vaccine (EV71 vaccine) administered alone or simultaneously. Methods: A multi-center, open-label, randomized controlled trial was performed involving 1080 healthy infants aged 6 months or 8 months from Shandong, Shanxi, Shaanxi, and Hunan provinces. These infants were divided into four simultaneous administration groups and EV71 vaccine separate administration group. Blood samples were collected from the infants before the first vaccination and after the completion of the vaccination. This trial was registered in the Clinical Trials Registry (NCT03519568). Results: A total of 895 were included in the per-protocol analysis. The seroconversion rates of antibodies against EV71 in four simultaneous administration groups (98.44% (189/192), 94.57% (122/129), 99.47% (187/188) and 98.45% (190/193)) were non-inferior to EV71 vaccine separate administration group (97.93% [189/193]) respectively. Fever was the most common adverse event, the pairwise comparison tests showed no difference in the incidence rate of solicited, systemic or local adverse events. Three serious adverse events related to the vaccination were reported. Conclusions: The evidence of immunogenicity and safety supports that the EV71 vaccine administered simultaneously with vaccines need to be administered during the same period of time recommended in China
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