Social structure and space use of Amur tigers(Panthera tigris altaica)in Southern Russian Far East based on GPS telemetry data

To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites:the Ussuriskii Reserve of southern Sikhote-Alin and the Land of the Leopard National Park in southwest Primorye,Russian Far East.Fixed kernel estimates of male home ranges were larger than those of female home ranges(P<0.05[mean 95%fixed kernel♀=401±205 km2;mean 95%fixed kernel♂=778±267 km2]).The home range size of females varied greatly,but on average was similar to estimates derived from earlier work further north.Low overlap of adjacent home ranges suggested that females retained exclusive territories.Real core areas of females overlapped only slightly,and remained stable over multiple years.The home ranges of adult males were smaller than those of males to the north,and in contrast to previous studies,high overlap among males indicated the absence of territoriality.Nonetheless,real core areas of males did not overlap,suggesting some spatial separation.In comparison to other tiger populations and other areas of the Russian Far East,the sex ratio in our 2 study areas was highly skewed towards males.We believe this skewed sex ratio resulted in the dissolution of territoriality of males due to an inability to defend individual females,with males resorting to scramble competition for mates.Continued monitoring of these sites to determine whether shifts in the sex ratio might result in a return to male territoriality would provide confirmation of our tentative hypothesis.

Underground space use of urban built-up areas in the central city of Nanjing:Insight based on a dynamic population distribution

With the expansion of cities and the emergence of various urban problems,urban underground space has been developed as a solution.In China’s urban transition context,there is a need for the development of underground space in urban built-up areas.In this casestudy of the central city of Nanjing,we used spatial analysis and statistical methods to characterize the underground space use of urban built-up areas from a dynamic spatiotemporal perspective.We first analyzed the relationship between the population distribution and the underground space use of the central city of Nanjing based on a Baidu heat map,which can reflect the real-time population distribution,and then,we explored the spatiotemporal characteristics and spatial structure of the underground space use in urban built-up areas.The analysis results provide a reference for planning to improve and optimize the layout of underground space in the central city of Nanjing and,more generally,for the stock-type planning of underground space in urban built-up areas.

Construction of PBIB Desings by Using Subspace of Vector Space over Finite Fields

A new transitivity theorem of the general linear group GLn(Fq)is proved. A kind of new PBIB desings is constructed.

Space-to-Ground Quantum Key Distribution Using a Small-Sized Payload on Tiangong-2 Space Lab

Quantum technology establishes a foundation for secure communication via quantum key distribution （QKD）. In the last two decades, the rapid development of QKD makes a global quantum communication network feasible. In order to construct this network, it is economical to consider small-sized and low-cost QKD payloads, which can be assembled on satellites with different sizes, such as space stations. Here we report an experimental demonstration of space-to-ground QKD using a small-sized payload, from Tiangong-2 space lab to Nanshan ground station. The 57.9-kg payload integrates a tracking system, a QKD transmitter along with modules for synchronization, and a laser communication transmitter. In the space lab, a 50MHz vacuum＋weak decoy-state optical source is sent through a reflective telescope with an aperture of 200mm. On the ground station, a telescope with an aperture of 1200mm collects the signal photons. A stable and high-transmittance communication channel is set up with a high-precision bidirectional tracking system, a polarization compensation module, and a synchronization system. When the quantum link is successfully established, we obtain a key rate over 100bps with a communication distance up to 719km. Together with our recent development of QKD in daylight, the present demonstration paves the way towards a practical satellite-constellation-based global quantum secure network with small-sized QKD payloads.

Do Larger and Older Individuals Occupy Better Areas in the Colony of Qinghai Toad-headed Agamas?

Group living reduces the chances of predation.This is also true for burrowing animals,which use burrows as refuges to escape predators.Living in the center of a colony is the safest because it offers access to the greatest number of burrows;however,it is stressful due to frequent aggressive interactions there.We predicted that larger and older animals should occupy areas of a colony with a higher density of burrows than smaller and younger ones.To test this prediction,we observed individually marked Qinghai toad-headed agamas(Phynocephalus vlangalii)from a single colony late in the breeding season when females were gravid.Density of burrows was the highest and distance between them the shortest in the center of the colony.Aggressive encounters were more frequent in the central part of the colony than on its periphery.We found a negative correlation between body size and distance to the center of the colony for females,but not for males.There was no such correlation between age of individuals and distance to the center of the colony.Females in this species likely compete with other females and males for central burrows in the colony even after mating season finishes.We suggest that gravid females likely compete for the dense burrows within the central part of the colony mainly due to their relatively lower sprint speed and higher probability of being caught by a predator if they are not refuged in a burrow.

Reduced Imaging Time and Improved Image Quality of 3D Isotropic T2-Weighted Magnetic Resonance Imaging with Compressed Sensing for the Female Pelvis

This study is to compare three-dimensional(3D)isotropic T2-weighted magnetic resonance imaging(MRI)with compressed sensing-sampling perfection with application optimized contrast(CS-SPACE)and the conventional image(3D-SPACE)sequence in terms of image quality,estimated signal-to-noise ratio(SNR),relative contrast-to-noise ratio(CNR),and the lesions’conspicuous of the female pelvis.Thirty-six females(age:51,28-73)with cervical carcinoma(n=20),rectal carcinoma(n=7),or uterine fibroid(n=9)were included.Patients underwent magnetic resonance(MR)imaging at a 3T scanner with the sequences of 3D-SPACE,CS-SPACE,and twodimensional(2D)T2-weighted turbo-spin echo(TSE).Quantitative analyses of estimated SNR and relative CNR between tumors and other tissues,image quality,and tissue conspicuity were performed.Two radiologists assessed the difference in diagnostic findings for carcinoma.Quantitative values and qualitative scores were analyzed,respectively.The estimated SNR and the relative CNR of tumor-to-muscle obturator internus,tumor-to-myometrium,and myometrium-to-muscle obturator internus was comparable between 3D-SPACE and CS-SPACE.The overall image quality and the conspicuity of the lesion scores of the CS-SPACE were higher than that of the 3D-SPACE(P<0.01).The CS-SPACE sequence offers shorter scan time,fewer artifacts,and comparable SNR and CNR to conventional 3D-SPACE,and has the potential to improve the performance of T2-weighted images.

A new methodology for computing birds＇ 3D home ranges

Background： So far, studies of avian space use are mostly realized in 2D, with the vertical dimension ignored. We propose here a new, relatively simple and computationally reasonable method for the estimation of volumetric （i.e. 3D） avian home ranges.Methods： Through accurate GPS data-loggers, we collected 25,405 GPS points on Lesser Kestrels＇ （Fdlco noumonni） space use during the nestling period in one main colony in Italy.We applied our 3D home range estimator to the whole GPS dataset, and also separately to diurnal and nocturnal GPS points.Results： The 3D colony home range resulted equal to 28.12 km3. By considering daytime and night-time separately, the volumetric home ranges resulted considerably different.Conclusions： Our 3D home range estimator, because of its intuitive and straightforward properties, can easily capi-talize on the datasets offered by modern biotelemetry （data-loggers, light detection and LIDAR sensors） and enhance conservation strategies for mitigating anthropogenic impacts on bird species. Its applications embrace, but are not limited to, more accurate estimates of collision risk with power lines, aircrafts and wind farms, and increased knowledge of birds＇space requirements in order to persist in their distribution areas.

Analysing the effect of stand density and site conditions on structure and growth of oak species using Nelder trials along an environmental gradient:experimental design,evaluation methods,and results

Background: Most current approaches in forest science and practice require information about structure and growth of individual trees rather than- or in addition to- sum and mean values of growth and yield at forest stand level as provided by classic experimental designs. By inventing the wheel design, Nelder provided the possibility to turn to the individual tree as basic information unit. Such trials provide valuable insights into the dependency of growth on stand density at particular sites.Methods: Here, we present an extension of the original design and evaluation by Nelder.(i) We established Nelder wheels along an environmental gradient through Europe in atlantic climate in Belgium and Germany, Mediterranean climate in Italy, continental climate in Hungary as well as on high land climate in Mexico. Such disjunct Nelder wheels along an environmental gradient can be regarded and analysed as a two-factor design with the factors of site condition and stand density.(ii) We present an advanced statistical approach to evaluate density dependent growth dynamics of trees planted in form of the Nelder design, which considers spatio-temporal autocorrelation.(iii)We prove the usefulness of the methods in improving ecological theory concerning density related productivity,trade-offs between facilitation and competition, and allometric relations between size variables.Results: First evaluations based on remeasured Nelder wheels in oak(Quercus robur L.) show a size growth differentiation during the first observation period. In particular, height growth is accelerated under higher competition indicating facilitation effects. We detect furthermore a high variability in allometric relations.Conclusions: The proposed design, methods, and results are discussed regarding their impact on forest practice,model building, and ecological theory. We conclude that the extended Nelder approach is highly efficient in providing currently lacking individual tree level information.

Proximate and ultimate factors that promote aggregated breeding in the Western Sandpiper

We report that Western Sandpipers （Calidris mauri） on Alaska’s Yukon-Kuskokwim River Delta exhibited aggregated breeding behavior at a relatively small spatial scale. Prior to clutch initiation, males performing song flight displays on a 36 ha plot were aggregated as were subsequent initial nesting attempts on the plot. We tested three hypotheses commonly invoked to explain aggregated breeding in territorial species （social mate choice, predation, and material resources hypotheses）, and found support for the material resources hypothesis, as dispersed individuals were more often associated with tundra habitat patches, and aggregated individuals nested more often in undulating-tundra habitat patches compared to patch availability. The pattern of habitat occupancy conformed to an ideal despotic distribution with aggregated nesting birds in undulating-tundra patches experiencing lower reproductive success. On our study plot, older, more aggressive males solicited females more often, and defended larger, more dispersed sites in tundra habitat patches, compared to younger, less aggressive males that were aggregated in undulating-tundra habitat patches. Breeding aggregations are often concentrated on or near a critical resource. In contrast, Western Sandpiper breeding aggregations occur when dominant and/or older individuals exclude younger, subordinate individuals from preferred habitat. Although many taxa of non-colonial birds have been reported to aggregate breeding territories, this is the first quantitative report of aggregated breeding behavior in a non-colonial monogamous shorebird species prior to hatch.

Study on the Layout of Urban Planning in Rapid Urbanization Areas under the Background of Air Pollution

China＇s urbanization has been over the medium-term process,which has made great achievements,but also triggered a huge problem of air pollution. Air pollution has become a big problem after the water pollution in China,and a serious threat to people＇s life and health. Under the background of ＂ the construction of beautiful China＂ and rapid urbanization,how to build a beautiful home has become the focus of attention. Taking Shenyang as an example,the author contrastively analyses the spatial distribution of the main air pollutants（ PM10,PM2. 5,and SO2） and the present situation of land use,and thus finds out the rules between pollutants distribution and land use. Then combining the urban planning scheme and the rules obtained above,reasonable suggestions are proposed for the scheme to improve the air quality,and reduce or avoid air pollution,and providing the basis for the construction of a piece of blue sky. The conclusions are as follows： 1 air pollutants concentration above Light Oil Gas Making Factory in south vice city of Shenyang reaches the peak value,and industrial point source is the main air pollutants emission source; 2 pollutants concentration above greenbelt is the lowest; 3 the overall spatial structure of urban planning can insulate the industrial agglomeration areas to some extent; greenbelt planning covers 40%- 50% of the area with high concentration of air pollutants,and it is suggested to achieve full coverage; traffic planning can achieve shunt most of the pollutants in many regions,but it can also expand the scope of pollutants in some certain regions,in such regions,it should reduce the road density.

A RESEARCH ON URBAN RECREATIONISTS' TRAVELING BEHAVIORS IN SHANGHAI

Urban recreationists consist of those who have used urban recreational facilities, no matter they are local residents or nonlocals. Traveling models will exert impacts not only on the use of urban recreational facilities but also on the development and management of recreational resources. Taking Shanghai as a sample of destinaton and origin of urban recreationists, the author did his study based on data from comprehensive travel measurement and users' survey, including field questionnaire survey, mailing questionnaire survey, home survey, and cordon monitonng. To analyze traveing models of urban recreationists in Shanghai, the author used techniques of Recreational Activity Space (RAS) and the Use Curve (UC) Analysis. Rogarding Shanghai as an origin, the author first discussed types and characteristics of the RASs which are presented by isotourist lines in the proper and outskirts of Shanghai, the Yangtze Delta and the China's Mainland respectively. These RASs reflect the trave directional bias of Shanghainese. Then the author regarded Shanghai as a deshnahon and analyzed the RASs of tounsts from Otier provinces, which demonstrated the attractiveness of and distance decay of Shanghai. He found that a U-shaped UC model existed in the distance decay under the influence of attractiveness and distance. Finally, the author suggested, that the availability, periodicity and attractiveness, besides distance, are the basic mechanisms that affect the urban recreationists' traveling models in a city such as Shanghai.

Analysis of erbium doped holey fiber using fundamental space filling mode

Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial fundamental space filling mode approach was utilized. By using EHll mode, we have numerically solved the rate equations of a three-level pumping scheme for a fiber laser. The obtained results have shown a good agreement with the other experimental results, recently. The results have predicted amplifiers with gain efficiencies as high as 10 dB/mW.

Space moving target detection using time domain feature

The traditional space target detection methods mainly use the spatial characteristics of the star map to detect the targets, which can not make full use of the time domain information. This paper presents a new space moving target detection method based on time domain features. We firstly construct the time spectral data of star map, then analyze the time domain features of the main objects(target, stars and the background) in star maps, finally detect the moving targets using single pulse feature of the time domain signal. The real star map target detection experimental results show that the proposed method can effectively detect the trajectory of moving targets in the star map sequence, and the detection probability achieves 99% when the false alarm rate is about 8×10^(-5), which outperforms those of compared algorithms.

Tri-axial accelerometry shows differences in energy expenditure and parental effort throughout the breeding season in long-lived raptors

Cutting-edge technologies are extremely useful to develop new workflows in studying ecological data,particularly to understand animal behavior and movement trajectories at the individual level.Although parental care is a well-studied phenomenon,most studies have been focused on direct observational or video recording data,as well as experimental manipulation.Therefore,what happens out of our sight still remains unknown.Using high-frequency GPS/GSM dataloggers and tri-axial accelerometers we monitored 25 Bonelli’s eagles Aquila fasciata during the breeding season to understand parental activities from a broader perspective.We used recursive data,measured as number of visits and residence time,to reveal nest attendance patterns of biparental care with role specialization between sexes.Accelerometry data interpreted as the overall dynamic body acceleration,a proxy of energy expenditure,showed strong differences in parental effort throughout the breeding season and between sexes.Thereby,males increased substantially their energetic requirements,due to the increased workload,while females spent most of the time on the nest.Furthermore,during critical phases of the breeding season,a low percentage of suitable hunting spots in eagles’territories led them to increase their ranging behavior in order to find food,with important consequences in energy consumption and mortality risk.Our results highlight the crucial role of males in raptor species exhibiting biparental care.Finally,we exemplify how biologging technologies are an adequate and objective method to study parental care in raptors as well as to get deeper insight into breeding ecology of birds in general.

GPS tracking of non-breeding ravens reveals the importance of anthropogenic food sources during their dispersal in the Eastern Alps

In many songbirds, the space use of breeders is well studied but poorly understood for non-breeders. In common ravens, some studies of non-breeders indicate high vagrancy with large individual differences in home range size, whereas others show that up to 40% of marked non-breeders can be regularly observed at the same anthropogenic food source over months to years. The aim of this study was to provide new insights on ravens＇ behavior during dispersal in the Eastern Alps. We deployed Global Positioning System （GPS） loggers on 10 individuals to gather accurate spatial and temporal information on their movements to quantify： 1） the dimension of the birds＇ space use （home range size with seasonal effects and daily/long-term travel distances）, 2） how long they stayed in a dispersal stage of wandering as opposed to settling temporarily, and 3） their destination of movements. We recorded movements of up to 40km per hour, more than 160km within 1 day and more than 11,000 km within 20 months, indicating high vagrancy. Switching frequently between temporarily settling and travelling large distances in short time intervals leads to extensive home ranges, which also explains and com- bines the different findings in the literature. The destinations are rich anthropogenic food sources, where the birds spent on average 75% of their time. We discuss how ravens may find these ＂feeding hot spots＂ and which factors may influence their decision to stay/leave a site. The strong dependence on anthropogenic resources found in this population may have implications for site management and conservation issues.

Restricted cross-scale habitat selection by American beavers

Animal habitat selection, among other ecological phenomena, is spatially scale dependent. Habitat selection by American beavers Castor canadensis （hereafter, beaver） has been studied at singular spatial scales, but to date no research addresses multi-scale selection. Our objectives were to determine if beaver habitat selection was specialized to semiaquatic habitats and if variables explaining habitat selection are consistent between landscape and fine spatial scales. We built maximum entropy （MaxEnt） models to relate landscape-scale presence-only data to landscape variables, and used generalized linear mixed models to evaluate fine spatial scale habitat selection using global positioning system （GPS） relocation data. Explanatory variables between the landscape and fine spatial scale were compared for consistency. Our findings suggested that beaver habitat selection at coarse （study area） and fine （within home range） scales was congruent, and was influenced by increasing amounts of woody wetland edge density and shrub edge density, and decreasing amounts of open water edge density. Habitat suitability at the landscape scale also increased with decreasing amounts of grass frequency. As territorial, central-place foragers, beavers likely trade-off open water edge density （i.e., smaller non-forested wetlands or lodges closer to banks） for defense and shorter distances to forage and obtain construction material. Woody plants along edges and expanses of open water for predator avoidance may limit beaver fitness and subsequently determine beaver habitat selection.

The problem and promise of scale in multilayer animal social networks

Scale remains a foundational concept in ecology.Spatial scale,for instance,has become a central consideration in the way we understand landscape ecology and animal space use.Meanwhile,scale-dependent social processes can range from fine scale interactions to co-occurrence and overlapping home ranges.Furthermore,sociality can vary within and across seasons.Multilayer networks promise the explicit integration of the social,spatial,and temporal contexts.Given the complex interplay of sociality and animal space use in heterogeneous landscapes,there remains an important gap in our understanding of the influence of scale on animal social networks.Using an empirical case study,we discuss ways of considering social,spatial,and temporal scale in the context of multilayer caribou social networks.Effective integration of social and spatial processes,including biologically meaningful scales,within the context of animal social networks is an emerging area of research.We incorporate perspectives that link the social environment to spatial processes across scales in a multilayer context.

Home range establishment and utilization by reintroduced lions(Panthera leo)in a small South African wildlife reserve

Understanding of animal spatial behavior is essential for informed management decisions.In southern Africa,reintroduction of lions(Panthera leo)to small reserves(<1000 km2)has increased since the early 2000s,however studies on their ranging behavior in these enclosed systems remain lacking.We applied Time Local Convex Hull(T-LoCoH)methods to study the home range establishment and utilization of 11 lions reintroduced to Dinokeng Game Reserve,South Africa,during 2011 through 2014.Lions established home ranges close to their release sites and during the following 3 years their home range sizes continued to increase,but in each individual case the size remained smaller than half of the reserve area(<70 km2).Space use strategies differed between the core and the entire home range,with higher frequency of visits found in core areas.Exceptionally high rates(>60 separate visits)around the largest dam and along rivers suggest the importance of water and its surrounding vegetation in the lions’space utilization pattern.The home range size did not differ with season or sex of the individuals,whereas shifts in locations of home ranges revealed differences in the response of the 2 sexes to territorial conflicts and management interventions.Our study shows a dynamic home range utilization pattern and highlights the importance of both fine-scale space use patterns(frequency and duration of visits)and broadscale home range changes in understanding the ranging behavior of reintroduced animals.

Application for developing countries:Estimating trip attraction in urban zones based on centrality

This paper introduced a network centrality-based method to estimate the volume of trip attraction in traffic analysis zones. Usually trip attraction volumes are estimated based on land use characteristics. However, executing of land use-based trip attraction models are severely constrained by the lack of updated land use data in developing countries. The proposed method used network centrality-based explanatory variables as ＂connectivity＂, ＂local integration＂ and ＂global integration＂. Space syntax tools were used to compute the centrality of road segments. GIS-based kernel density estimation method was used to transform computed road segrnent-based centrality values into traffic analysis zone. Trip attraction values exhibited significant high correlation with connectivity, global and local integration values. The study developed and validated model to estimate trip attraction by using connectivity, local integration and global integration values as endogenous variables with an accepted level of accuracy （R2 〉 0.75）. The proposed approach required minimal data, and it was easily executed using a geographic information system. The study rec- ommended the proposed method as a practical tool for transport planners and engineers, especially who work in developing countries and where updated land use data is unavailable.