Self-similarity of spanwise rotational motions’population trends in decelerating open-channel flow

Decelerating open-channel flow is a type of flow that gradually moves forward with decreasing velocity and increasing water depth.Although all flow parameters change along the streamwise direction,previous studies have revealed that these parameters’vertical distributions at different sections can be universally described with a single profile when being nondimensionalised by appropriate scales.This study focuses on the population trends of spanwise rotational motions at various sections along the main flow direction by particle imaging velocimetry(PIV)measurement.The wall-normal population distributions of density,radius,swirling strength,and convection velocity of the prograde and retrograde motions show similar trends in uniform open-channel flows.The dimensionless representation is invariant along the main flow direction.This study’s results indicate the self-similar characteristic of population trends of spanwise rotational motions prevails in decelerating open-channel flow.

Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program

In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point.

Trends of Population Growth in China:Maximum Number Will Exceed 1.5 Billion

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Post Drought Population Status and Trend of Specialized Browsers in the Mid Kenya-Tanzania Borderland

We examined the population status, trend and distribution of Gerenuk, Fringe-eared Oryx and Lesser kudu in the Northern Tanzania and Southern Kenya borderland after the 2007 to 2009 drought. The species were characterized by low numbers and sparsely distributed in the borderland but were more prevalent and abundant in the Amboseli region. However, West Kilimanjaro had the highest positive change in density between 2010 and 2013 [Gerenuk = +1650.48 ± 1150.31, lesser kudu = +912.78 ± 487.63 and Fringe-eared Oryx = +366.65 ± 233.32]. Changes in density and composition varied seasonally among the different sectors of the borderland, with Gerenuk having the highest change in the Amboseli area during the wet season. Lesser kudu had the highest change in Amboseli and Kilimanjaro during the wet season while Fringe-eared Oryx had the highest change in the wet season in West Kilimanjaro area. Spatial distribution of the species varied seasonally and across different sectors of the borderland. In the dry season, Gerenuk exhibited a clumped distribution mainly in Amboseli National Park, and between Natron and West Kilimanjaro but in the wet season, it spread out more though higher concentrations were still found Amboseli and West Kilimanjaro. Lesser concentrated in mostly in West Kilimanjaro and Amboseli during the dry season but was widely dispersed during the wet season. Similarly, during the dry season, the Fringe-eared Oryx was confined in the Amboseli and West Kilimanjaro areas but during the wet season, it much more spread out with clusters in the Mbirikani area of the Amboseli region and a few places in Magadi, Natron and West Kilimanjaro. Management implications of the findings obtained in this study area here-in discussed.

Population Status and Trend of the Maasai Ostrich in the Mid Kenya—Tanzania Borderland

The Maasai ostrich (Struthio camelus) is a the largest avian species in East Africa and though it’s not considered to be a species of conservation concern, some populations are on the decline and this is attributed to bush meat activities, predation on their eggs illegal consumption by humans, habitat destruction and forage competition with other large wildlife species. Climate change is also emerging to be another major threat due to interference with food availability which in turn interferes with the breeding rhythm. Thus, this study examined the population status, trend and distribution of the Maasai ostrich in the Southern Kenya and Northern Tanzania borderland after the 2007 to 2009 drought. The results showed that the species was found across the entire borderland but the Amboseli region had the highest number and density of Maasai ostrich (726.00 ± 100.9;0.08 ± 0.01 ostriches per km2), followed by Lake Natron area (330.8 ± 69.8;0.05 ± 0.01 ostriches per km2) and the least was in West Kilimanjaro (85.5 ± 18.0;0.03 ± 0.01 ostriches per km2). Drought caused a decline in the population of the Maasai ostrich but the Amboseli area experienced the highest decline in density (?13.44 ± 12.61) compared to other borderland sectors. However, the populations increased in most sectors after the drought, and wet season numbers and densities were higher than the dry season. The highest positive increase in number and density was in Lake Natron area (+85.65 ± 91.06) followed by West Kilimanjaro (+68.39 ± 59.54), and the least was in the Magadi area (+22.26 ± 32.05). There is a need to enhance conservation of avian species like the Maasai ostrich other than just focusing on the charismatic species such as the African elephant and black rhino. We therefore recommend joint collaboration in monitoring all large wildlife populations across the Kenya-Tanzania borderland with a view of understanding their status, trend and best management actions that can enhance their conservation.

Influence of land use change on the waterbird community of Sihwa Lake,Republic of Korea

Background:Land use and development alter mudflat and wetland habitat availability,although mudflats and wetlands provide important stopover habitats for shorebirds during the spring and autumn migrations and support communities of ducks and geese during the winter months in the Republic of Korea.This study investigated land use changes around Sihwa Lake(Republic of Korea)and evaluated the effect of these changes on waterbird community characteristics.Methods:We conducted a land-use-change analysis at the medium-resolution level using land cover maps for 2001,2007,2009,and 2014.Also,a tidal stream survey was conducted in Sihwa Lake and the surrounding reclaimed mudflats every season for 10 years(2003-2012)to identify the seasonal and interannual variations in waterbird species composition.To determine the total annual waterbird species and population counts,species diversity index,and interspecies variations,a TRIM(trends and indices for monitoring data)analysis was used.Results:Wetland area decreased more than 10%while agricultural land,barren land,and grassland area increased more than 10%due to continuous reclamation activities around Sihwa Lake.Barren land later turned into agricultural land or other land use.Sixty-three species and 566,623 individuals were recorded.The number of species,population size,and species diversity index by year and by species showed decreasing trends that were more marked in spring and summer.Furthermore,seasonal and annual variations in waterbird species composition showed decreasing trends in dabbling ducks,herons,grebes,and shorebirds but diving ducks displayed increasing trends.In particular,shorebirds were reduced to a greater extent than other waterbird species because of the reduction and simplification of the intertidal zone,and shallow waters caused by reclamation and road construction.Conclusions:Increased development and construction around Sihwa Lake has altered migratory shorebird populations with a general decline in species diversity and population size.The greatest decline was observed in wading birds,while diving duck populations showed increasing trends.

The Impacts of the Universal Two-Child Policy on China's Population

The universal two-child policy,implemented in October,2015,is considered to be the most significant adjustment in the history of China's family planning program.Using data from the 2014 national population sampling survey,this paper employs a population group-component calculation and projection method to compute the number of target population in 2016 and then to estimate the number of extra births that are likely to result from implementation of the universal two-child policy.The results show that the total number of extra births is estimated to be approximately 17.2 million in the years 2017-2021,with the number of extra births per year ranging from approximately 1.6 to 4.7 million.This will lead to a dramatic shift in China's TFR from an estimated 1.6 in 2016 to one approaching the replacement level,and then dropping to a projected 1.7.With the universal two-child policy in place,China's total population will grow to about 1.45 billion around 2028 and then gradually begin shrioking.The labor force will become larger under the universal two-child policy than it would if the stricter birth control policy were maintained,with an estimated 50 million additional people aged 15-59 in 2050.With implementation of China's new fertility policy,an estimated 34%of the population will be over 60 years of age in 2050,almost three percentage points lower than the level if the former fertility policy were continued.

Estimating index of population trend by re-sampling techniques （jackknife and bootstrap） and its application to the life table study of rice leaf roller, Cnaphalocrocis medinalis （Lepidoptera： Pyralidae）

Taking a published natural population life table of rice leaf roller, Cnaphalocrocis medinalis （Lepidoptera： Pyralidae）, as an example, we estimated the population trend index, I, via re-sampling methods （jackknife and bootstrap）, determined its statistical properties and illustrated the application of these methods in determining the control effectiveness of bio- agents and chemical insecticides. Depending on the simulation outputs, the smoothed distribution pattern of the estimates of I by delete-1 jackknife is visually distinguishable from the normal density, but the smoothed pattern produced by delete-d jackknife, and logarithm- transformed smoothed patterns produced by both empirical and parametric bootstraps, matched well the corresponding normal density. Thus, the estimates of I produced by delete-1 jackknife were not used to determine the suppressive effect of wasps and insecticides. The 95% percent confidence intervals or the narrowest 95 percentiles and Z-test criterion were employed to compare the effectiveness of Trichogrammajaponicum Ashmead and insecticides （powder, 1.5% mevinphos ＋ 3% alpha-hexachloro cyclohexane） against the rice leaf roller based on the estimates of I produced by delete-d jackknife and bootstrap techniques. At a = 0.05 level, there were statistical differences between wasp treatment and control, and between wasp and insecticide treatments, if the normality is ensured, or by the narrowest 95 percentiles. However, there is still no difference between insecticide treatment and control. By Z-test criterion, wasp treatment is better than control and insecticide treatment with P-value 〈 0.01. Insecticide treatment is similar to control with P-value 〉 0.2 indicating that 95% confidence intervals procedure is more conservative. Although similar conclusions may be drawn by re-sampling techniques, such as the delta method, about the suppressive effect of trichogramma and insecticides, the normality of the estimates can be checked and guaranteed, and the correlation among sequential life stages of rice leaf roller is also considered in the estimation. Judged by the P-values from Z-test, the delta method is more conservative.

A Model of Vary in Distance Leslie Matrix of the Giant Panda's Population at Wu-YiPeng,Wolong

A new Vary in Distance Leslie Matrix is adopted to process the observed data of a giant panda population’s development trend dynamics with unequal distance age groups. Results show that this new method adopted is much simpler than the usual lesile Matrix analysis, and no need of deviding the pandas into equal distance age groups and no so many asumptions are needed as in the usual Leslie Methods. We only changed the meaning of some elements in Leslie Matrix and processed the developmental trend of panda population in Wolong Wu Yi Peng successfully we also carried out a sensitivity analysis of many parameters as well as the computer simulation.