scholarly journals Modelling the Spatial Distribution of Habitats of Main Cephalopod Taxa in Inshore Waters of Zhejiang Province at Spring and Autumn

2021 ◽  
Author(s):  
Feng Chen ◽  
Guangen Wei ◽  
Nan Li ◽  
Zhou Fang ◽  
Hongliang Zhang ◽  
...  
Keyword(s):  
Marginal Zone ◽  
Remote Sensing Data ◽  
Zhejiang Province ◽  
Distribution Area ◽  
Sustainable Utilization ◽  
Suitability Index ◽  
Distribution Ranges ◽  
Commercially Important ◽  
Inshore Waters ◽  
The Individual

Abstract Due to the declining catch of the ground fish, cephalopod as a short-lived invertebrate with commercially important value has become the main fishery target species of East China Sea (ECS) in recent decades. Therefore, it is necessary to explore its habitat for the sustainable utilization. In this study, with the individual density of cephalopod derived from the fishery survey data in the coast of Zhejiang Province from 2014 to 2019 and remote sensing data, the habitat suitability index (HSI) model of typical cephalopod (Loliginidae, Octopodidae, Sepiidae, and Sepiolidae) in spring and autumn was obtained. The habitat isolines of core zone, common zone and marginal zone were also established and then compared among different typical cephalopod taxa based on arithmetic mean model (AMM). The distribution ranges of SST and chlorophyll-a of cephalopod were respectively 12.95~21.91 ℃ and 0.52~5.57 mg/m3 in spring and 17.02~22.94℃ and 0.26~6.02 mg/m3 in autumn. The prediction results of the HSI model suggested that the cephalopod distribution areas were concentrated in the range of 122°~124°E, 29.5°~31°N, displaying the distribution direction from coastal area to the northeast. The accumulative density of the four cephalopod taxa in the area with HSI>0.6 accounted for 73.9%. The overlap between the prediction results of HSI model and the actual density in 2019 also proved the good predictability of HSI model based on AMM. Four cephalopod taxa showed distribution differences. Sepiolidae had the widest distribution area, whereas Octopodidae had the narrowest distribution area.

Mastication of Rubber. II. Interpolymerization of Natural Rubber and Neoprene on Cold Milling

1956 ◽  
Vol 29 (2) ◽  
pp. 427-437
Author(s):  
D. J. Angier ◽  
W. F. Watson
Keyword(s):  
Free Radicals ◽  
Natural Rubber ◽  
Small Molecules ◽  
The Other ◽  
Polymer Molecules ◽  
Commercially Important ◽  
The Individual ◽  
Cold Mill ◽  
General Method ◽  
Butadiene Styrene

Abstract The softening of elastomers on cold milling results from scission of the polymer molecules by the applied shearing forces. The ruptured chains are free radicals, which can undergo mutual combination, interaction with oxygen and various additives, and branching (grafting) on to other polymer molecules. A general method of producing graft and block interpolymers between elstomers is therefore indicated, namely, to cold-mill the polymers together in the absence of small molecules which can terminate the polymeric radicals in order that the radicals may cross-terminate or graft onto the polymer molecules of the other type. A survey of several pairs of the commercially important elastomers, natural rubber, butadiene-styrene, Neoprene, and butadiene-acrylonitrile, has shown that cold milling does effect interlinking. Detailed results for the rubber-Neoprene system are reported in this communication. Experimental verification of polymer interlinking was obtained from the solubility properties of the milled elastomers. Cold milling of Neoprene under nitrogen produces gel, whereas of natural rubber does not, but the milling of mixtures gives gels containing natural rubber. Also, the solubilities and precipitation of the milled mixtures cannot be accounted for by these properties of the individual polymers. Finally, Neoprene-natural rubber mixtures, after and not before cold-milling, can be cross-linked by magnesium oxide, with rubber bound into the vulcanizate.

scholarly journals ­Change of niche in guanaco (Lama guanicoe): The effects of climate change on habitat suitability and lineage conservatism in Chile

2018 ◽  
Author(s):  
Andrea G Castillo ◽  
Dominique Alò ◽  
Benito A González ◽  
Horacio Samaniego
Keyword(s):  
Climate Change ◽  
Ecological Niche ◽  
Fundamental Problem ◽  
Interspecific Interactions ◽  
Distribution Area ◽  
Niche Conservatism ◽  
Evolutionary Patterns ◽  
Lama Guanicoe ◽  
Ecological Features ◽  
Distribution Ranges

Background. A fundamental problem in the biogeography of climate change is to understand and predict how environmental factors determine whether organisms will alter their seasonal activities, home ranges, migratory patterns, abundances, and interspecific interactions. The main goal of this contribution was to define the ecological niche of the guanaco (Lama guanicoe) to describe potential distributional changes and to assess the relative importance of niche conservatism and divergence processes among the two lineages described for the species. Methods. We used current and future projections of climate change under two extreme GHG emission scenarios (RCP2.6 and RCP8.5) to evaluate changes of the environmental niche and future distribution of the largest mammal in the southern cone of South America. Evaluation of niche conservatism and divergence are based on identity and background similarity tests. Results. We show that: a) the current geographic distribution of lineages and contact population prescribe different climatic requirements that are related to the geographic areas where these lineages are located; b) future distribution models predict a decrease in the distribution surface under both scenarios; c) the surface area predicted to be gained, lost, and unchanged is ~15%, 15- 26%, and 85- 75% respectively; d) a 3% increase of areal protection is expected if the current distribution of protected areas is maintained, however this is expected to occur at the expense of a large reduction of high quality habitats under the best scenario and; e) current and future distribution ranges of guanaco mostly adhere to phylogenetic niche divergence hypotheses between linages (L. g. cacsilensis and L. g. guanicoe). However, both lineages and the contact population show niche conservatism given niche similarity tests. Discussion. Associating environmental variables to species ecological niche seem to be an important aspect of unveiling the particularities of, both, evolutionary patterns and ecological features that species face in a changing environment. We have provided specific descriptions of how such patterns may play out under the most extreme climate change predictions, thereby, providing a grim outlook of the future potential distribution of guanaco. From an ecological perspective, while a slightly larger distribution area is expected, this may come with an important reduction of available quality habitats. From the evolutionary perspective, we describe the limitations of the contact population´s niche to merge with the northern and/or southern niche lineages of guanaco exposing the complexities of understanding evolutionary patterns across this taxon as it experiences climate change dynamics.

Predicting the impact of Giant Molerat influenced vegetation on Sanetti Plateau, Bale Mountains, Ethiopia

2020 ◽  
Author(s):  
Luise Wraase ◽  
Victoria Reuber ◽  
Philipp Kurth ◽  
Nina Farwig ◽  
Georg Miehe ◽  
...  
Keyword(s):  
Ecosystem Engineer ◽  
Temporal Structure ◽  
Remote Sensing Data ◽  
Soil Formation ◽  
Vegetation Pattern ◽  
Ecosystem Engineers ◽  
Vegetation Patterns ◽  
Local Soil ◽  
The Individual ◽  
The Impact

<p>Ecosystem engineers continuously shape and re-shape the spatial and temporal structure of the environment. Burrowing animals are an important group of ecosystem engineers, because of their ability to rework sediments and soils with consequences for e.g. soil formation and vegetation patterns. Simultaneous, burrowing animals depend on climate, local soil characteristics and vegetation. The endemic Giant Molerat (GMR) is a burrowing animal and important ecosystem engineer in the Bale Mountains. As part of the Bale Mountain Exile Hypothesis Project, the aim of this study is to investigate (1) the interlinkages between GMR, climate and vegetation patterns as well as (2) to upscale the influence of GMR on the vegetation pattern across the plateau with Sentinel satellite data. Field data comprise 47 paired plots of 5m x 5m with and without GMR activity. Additionally, 1.500 independent GMR burrow openings have been mapped. For investigating interlinkages, all parameters are first pre-analysed for correlations and their dependencies (1). In the following these results, the remote sensing data and the individual variables are implemented into the prediction model. To increase the accuracy, an error correction of the model is pursued. For this, the area is calculated into likelihoods of areas influenced by GMR, based on the vegetation survey pairs serving as training areas for the correction. The corrected results are used as final input model in a machine learning-based classification approach using Random Forest with forward-feature selection and leave-feature-out option (2). In the following the results of this ongoing upscaling approach used for the Sanetti Plateau, Ethiopia is presented.</p>

scholarly journals Surveillance for Adverse Events following Immunization from 2008 to 2011 in Zhejiang Province, China

2012 ◽  
Vol 20 (2) ◽  
pp. 211-217 ◽  
Author(s):  
Yu Hu ◽  
Qian Li ◽  
Luoya Lin ◽  
Enfu Chen ◽  
Yaping Chen ◽  
...  
Keyword(s):  
Adverse Events ◽  
Injection Site Reaction ◽  
Influenza Virus Vaccine ◽  
H1n1 Influenza ◽  
Reporting Rate ◽  
Zhejiang Province ◽  
The Individual ◽  
Zhejiang Provincial ◽  
Two Peaks ◽  
Reporting Rates

ABSTRACTThis study summarizes passive surveillance data for adverse events following immunization (AEFI) reported to the National AEFI Surveillance System (NASS) in Zhejiang province and describes reporting trends from 2008 to 2011. AEFI reporting rates were calculated using denominator data from the Individual Immunization Information System and the Zhejiang provincial Bureau of Statistics. A total of 6,265 AEFI records were reported; the overall reporting rate was 9.2 per 100,000 doses. There were two peaks of reporting rates, which were associated mainly with the introduction of the pandemic H1N1 influenza virus vaccine (pH1N1) in 2009 and the measles-mumps vaccine (MM) campaign in 2010. The majority of the AEFI described nonserious events. Fifteen deaths were recorded, but only one was possibly related to immunization. The most frequently reported reactions were fever and injection site reaction. Vaccines distributed in Zhejiang province have proven to be generally safe. The data on AEFI surveillance provide a reference point for ongoing reporting of trends and illustrate the value of the NASS database as a surveillance tool for monitoring of AEFI.

scholarly journals Remote Sensing Based Spatial-Temporal Monitoring of the Changes in Coastline Mangrove Forests in China over the Last 40 Years

2021 ◽  
Vol 13 (10) ◽  
pp. 1986
Author(s):  
Junyao Zhang ◽  
Xiaomei Yang ◽  
Zhihua Wang ◽  
Tao Zhang ◽  
Xiaoliang Liu
Keyword(s):  
Remote Sensing ◽  
Landscape Pattern ◽  
Remote Sensing Data ◽  
Distribution Area ◽  
Mangrove Forests ◽  
Landscape Index ◽  
National Scale ◽  
Spatial Changes ◽  
Temporal And Spatial ◽  
Degree Of Fragmentation

As a developing country, China’s mangrove landscape pattern has undergone significant temporal and spatial changes over the last four decades. However, we know little about the changes in the mangrove landscape pattern characteristics other than the area at the national scale. The analysis of mangrove landscape pattern changes from different perspectives on a national scale can provide scientific support for mangrove protection and restoration. In this study, the temporal and spatial changes in the pattern of the mangrove landscape over the last 40 years in China were analyzed based on remote sensing data with high classification accuracy (99.3% of 2018). First, according to the natural geographical conditions of the coastal zone and the distribution of the mangroves, the distribution area of the mangroves in China was divided into 31 natural shores. Then, by selecting representative landscape indexes and constructing an integrated landscape index, the spatial-temporal changes in the landscape pattern of China’s mangroves over the last 40 years were analyzed based on five perspectives: Total area change, shape complexity, connectivity, fragmentation, and the integrated state of the landscape. From a temporal viewpoint, before 2000, the total area of each shore exhibited a downward trend, and the degree of connectivity deteriorated continuously, but the degree of fragmentation was stable at a low level. After 2000, although the total area improved, the degree of fragmentation gradually increased. The spatial changes are mainly reflected by the fact that the shores in Guangdong and Hainan exhibited significant differences within the same province. Based on the above analysis, corresponding scientific suggestions are proposed from temporal and spatial viewpoints to provide guidance for mangrove management and protection in China and to provide a reference for mangrove research in other regions of the world.

scholarly journals Assessing volumetric change distributions and scaling relations of retrogressive thaw slumps across the Arctic

2021 ◽  
Author(s):  
Philipp Bernhard ◽  
Simon Zwieback ◽  
Nora Bergner ◽  
Irena Hajnsek
Keyword(s):  
Regional Differences ◽  
Scaling Laws ◽  
Remote Sensing Data ◽  
High Arctic ◽  
The Arctic ◽  
Scaling Relations ◽  
Volumetric Change ◽  
Total Size ◽  
Inverse Gamma ◽  
The Individual

Abstract. Arctic ice-rich permafrost is becoming increasingly vulnerable to terrain altering thermokarst, and among the most rapid and dramatic of these changes are retrogressive thaw slumps (RTS). They initiate when ice-rich soils are exposed and thaw, leading to the formation of a steep headwall which retreats during the summer months. These impacts, the distribution and scaling laws governing RTS changes within and between regions are unknown. Using TanDEM-X-derived digital elevation models, we estimated RTS volume and area changes over a 5-year period. We contrasted 9 regions (Eurasia: 4, North America: 5), with a total size of 220,000 km3, and over that time all 1853 RTSs combined mobilized a total volume of 17 · 106 m3 yr−1 corresponding to a volumetric change density of 77 m3 yr−1 km−2. Our remote sensing data revealed inter-regional differences in mobilized volumes, scaling laws and terrain controls. The area-to-volume scaling could be well described by a power law with an exponent of 1.15 across all regions, however the individual regions had scaling exponents ranging from 1.05 to 1.37 indicating that regional characteristics need to be taken into account when estimating RTS volumetric change from area change. The distributions of RTS area and volumetric change rates followed an inverse gamma function with a distinct peak and an exponential decrease for the largest RTSs. We found that distributions in the high Arctic were shifted towards larger values. Among the terrain controls on RTS distributions that we examined, slope, adjacency to waterbodies and aspect, the latter showed the greatest, but regionally variable association with thaw slump occurrence. Accounting for the observed regional differences in volumetric change distributions, scaling relations and terrain controls may enhance the modelling and monitoring of Arctic carbon, nutrient and sediment cycles.

scholarly journals ­Change of niche in guanaco (Lama guanicoe): The effects of climate change on habitat suitability and lineage conservatism in Chile

2018 ◽  
Author(s):  
Andrea G Castillo ◽  
Dominique Alò ◽  
Benito A González ◽  
Horacio Samaniego
Keyword(s):  
Climate Change ◽  
Ecological Niche ◽  
Fundamental Problem ◽  
Interspecific Interactions ◽  
Distribution Area ◽  
Niche Conservatism ◽  
Evolutionary Patterns ◽  
Lama Guanicoe ◽  
Ecological Features ◽  
Distribution Ranges

Background. A fundamental problem in the biogeography of climate change is to understand and predict how environmental factors determine whether organisms will alter their seasonal activities, home ranges, migratory patterns, abundances, and interspecific interactions. The main goal of this contribution was to define the ecological niche of the guanaco (Lama guanicoe) to describe potential distributional changes and to assess the relative importance of niche conservatism and divergence processes among the two lineages described for the species. Methods. We used current and future projections of climate change under two extreme GHG emission scenarios (RCP2.6 and RCP8.5) to evaluate changes of the environmental niche and future distribution of the largest mammal in the southern cone of South America. Evaluation of niche conservatism and divergence are based on identity and background similarity tests. Results. We show that: a) the current geographic distribution of lineages and contact population prescribe different climatic requirements that are related to the geographic areas where these lineages are located; b) future distribution models predict a decrease in the distribution surface under both scenarios; c) the surface area predicted to be gained, lost, and unchanged is ~15%, 15- 26%, and 85- 75% respectively; d) a 3% increase of areal protection is expected if the current distribution of protected areas is maintained, however this is expected to occur at the expense of a large reduction of high quality habitats under the best scenario and; e) current and future distribution ranges of guanaco mostly adhere to phylogenetic niche divergence hypotheses between linages (L. g. cacsilensis and L. g. guanicoe). However, both lineages and the contact population show niche conservatism given niche similarity tests. Discussion. Associating environmental variables to species ecological niche seem to be an important aspect of unveiling the particularities of, both, evolutionary patterns and ecological features that species face in a changing environment. We have provided specific descriptions of how such patterns may play out under the most extreme climate change predictions, thereby, providing a grim outlook of the future potential distribution of guanaco. From an ecological perspective, while a slightly larger distribution area is expected, this may come with an important reduction of available quality habitats. From the evolutionary perspective, we describe the limitations of the contact population´s niche to merge with the northern and/or southern niche lineages of guanaco exposing the complexities of understanding evolutionary patterns across this taxon as it experiences climate change dynamics.

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