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1. Assessment of the State of Tulipa lehmanniana Mercklin Populations Under the Conditions of the Kyzylkum Desert

Author:
Shomurodov, Kh. F.; Abduraimov, O. S.; Adilov, B. A.
Source:
Arid ecosystems 2021 v.11 no.1 pp. 83-90
ISSN:
2079-0961
Subject:
population density,   etc   ; Tulipa; leaves;     Show all 3 Subjects
Abstract:
... Coenopopulations of Tulipa lehmanniana Merckl. have been studied and assessed as normal, with the full range of age groups, except for the Tamdyn population, for which no senile fraction has been observed. The complex of determinating indices of coenopopulations with high variation coefficients includes the population density, projective cover, and the width of the bottom leaf. Coenopopulations re ...
DOI:
10.1134/S2079096121010133

2. A natural experimental study of improvements along an urban canal: impact on canal usage, physical activity and other wellbeing behaviours

Author:
Benton, Jack S.; Cotterill, Sarah; Anderson, Jamie; Macintyre, Vanessa G.; Gittins, Matthew; Dennis, Matthew; French, David P.
Source:
Theinternational journal of behavioral nutrition and physical activity 2021 v.18 no.1 pp. 19
ISSN:
1479-5868
Subject:
population density,   etc   ; data collection; green infrastructure; nutrition; people; vegetation;     Show all 6 Subjects
Abstract:
... BACKGROUND: There are few robust natural experimental studies of improving urban green spaces on physical activity and wellbeing. The aim of this controlled natural experimental study was to examine the impact of green space improvements along an urban canal on canal usage, physical activity and two other wellbeing behaviours (social interactions and taking notice of the environment) among adults ...
DOI:
10.1186/s12966-021-01088-w

3. Microplastic contamination is ubiquitous in riparian soils and strongly related to elevation, precipitation and population density

Author:
Zhou, Yanfei; He, Gang; Jiang, Xiaoliang; Yao, Lunguang; Ouyang, Lu; Liu, Xiaoyan; Liu, Wenzhi; Liu, Yi
Source:
Journal of hazardous materials 2021 v.411 pp. 125178
ISSN:
0304-3894
Subject:
population density,   etc   ; ecosystems; ecotoxicology; microplastics; polyamides; Yangtze River;     Show all 6 Subjects
Abstract:
... Although environmental research has recently begun to focus on the ubiquity of microplastics in terrestrial systems, there is still lack of comprehensive data which describe microplastics levels in soils and the factors influencing the distribution of this contaminant. Here, we show that microplastics contamination (3877 ± 2356 p kg¹) is omnipresent in numerous soil samples collected along the Yan ...
DOI:
10.1016/j.jhazmat.2021.125178

4. State and local pressures drive plastic pollution compliance strategies

Author:
Willis, K.A.; Hardesty, B.D.; Wilcox, C.
Source:
Journal of environmental management 2021 v.287 pp. 112281
ISSN:
0301-4797
Subject:
population density,   etc   ; compliance; laws and regulations; pollution; socioeconomics; waste management;     Show all 6 Subjects
Abstract:
... Environmental harm from plastic pollution partly results from compliance failure at the individual level. Three prevalent non-compliant motivations for polluting plastics include economic gains, ignorance of the rules and unlikely penalization from inadequately enforced rules. Given compliance is primarily the responsibility of local waste management, we conducted interviews to gain insights to th ...
DOI:
10.1016/j.jenvman.2021.112281

5. Accessibility of green areas for local residents

Author:
Laan, Corine M.; Piersma, Nanda
Source:
Environmental and sustainability indicators 2021 v.10 pp. 100114
ISSN:
2665-9727
Subject:
population density,   etc   ; green infrastructure; mathematical models; population size;     Show all 4 Subjects
Abstract:
... Green spaces play an important role in urban areas. We study the accessibility of green urban areas by combining open data sets about green with population size data. We develop a mathematical model to define the population density of a green area and calculate the available green space depending on the location. To this end, we do not only consider walking distance to and size of the green area, ...
DOI:
10.1016/j.indic.2021.100114

6. Ipomoea coccinea L. (Convolvulaceae): a new introduced alien plant species in Turkey

Author:
Onen, H.; Ozaslan, C.; Farooq, S.; Jones, C. A.
Source:
Bulletin OEPP 2021 v.51 no.1 pp. 207-212
ISSN:
0250-8052
Subject:
population density,   etc   ; Ipomoea coccinea; flora; introduced plants; risk assessment; tea;     Show all 6 Subjects
Abstract:
... This study reports the first record of Ipomoea coccinea L. [(Convolvulaceae), red morning glory] from Turkey. The literature review revealed that this taxon has not been recorded yet for the flora of Turkey. The species was mainly observed on the embankments along the Ardeşen‐Çamlıhemşin road during 2016. It was again recorded during 2019 with a certain extension of the invaded area and a signific ...
DOI:
10.1111/epp.12730

7. Spatiotemporal shifts of population and war under climate change in imperial China

Author:
Zhang, Shengda; Zhang, David Dian; Pei, Qing
Source:
Climatic change 2021 v.165 no.1-2 pp. 11
ISSN:
0165-0009
Subject:
population density,   etc   ; climate change; cold; latitude; temperature; China;     Show all 6 Subjects
Abstract:
... Studies on the spatiotemporal relationship between historical climate change and the patterns of population and war are rare. In this research, statistical methods (such as correlation test and Granger causality analysis) and visualization technique are applied to demonstrate how temperature, in terms of long-term trend and cyclic mode, fundamentally affects the temporal-spatial variations of popu ...
DOI:
10.1007/s10584-021-03042-y

8. Modeling how to achieve localized areas of reduced white-tailed deer density

Author:
Van Buskirk, Amanda N.; Rosenberry, Christopher S.; Wallingford, Bret D.; Domoto, Emily Just; McDill, Marc E.; Drohan, Patrick J.; Diefenbach, Duane R.
Source:
Ecological modelling 2021 v.442 pp. 109393
ISSN:
0304-3800
Subject:
population density,   etc   ; Odocoileus virginianus; deer; dispersal behavior; females; models; Pennsylvania;     Show all 7 Subjects
Abstract:
... Localized management of white-tailed deer (Odocoileus virginianus) involves the removal of matriarchal family units with the intent to create areas of reduced deer density. However, application of this approach has not always been successful, possibly because of female dispersal and high deer densities. We developed a spatially explicit, agent-based model to investigate the intensity of deer remov ...
DOI:
10.1016/j.ecolmodel.2020.109393

9. Impact of removal on occupancy patterns of the invasive rainbow lorikeet (Trichoglossus moluccanus) in Tasmania

Author:
Cobden, McLean; Alves, Fernanda; Robinson, Sue; Heinsohn, Robert; Stojanovic, Dejan
Source:
Austral ecology 2021 v.46 no.1 pp. 31-38
ISSN:
1442-9985
Subject:
population density,   etc   ; biodiversity; introduced species; population size; surveys; Tasmania;     Show all 6 Subjects
Abstract:
... Introduced species may threaten both biodiversity and agriculture, necessitating an understanding on the factors that influence their distribution, and the efficacy of control measures. In Tasmania, Australia, the introduced rainbow lorikeet (Trichoglossus moluccanus) may be widespread, but data on where they occur and the efficacy of control methods are limited. We used an occupancy modelling fra ...
DOI:
10.1111/aec.12954

10. Identifying the nonlinear relationship between free-floating bike sharing usage and built environment

Author:
Chen, Enhui; Ye, Zhirui
Source:
Journal of cleaner production 2021 v.280 pp. 124281
ISSN:
0959-6526
Subject:
population density,   etc   ; bicycling; case studies; employment; land use; models; planning;     Show all 7 Subjects
Abstract:
... A free-floating bike sharing system is an up-and-coming and marketable solution to promote transport flexibility and health benefits, which many people regard as a realistic way of generating more environmentally-friendly trips. Although many studies have investigated the associations between bike sharing usage and built environment, the existing literature has limited evidence about the relative ...
DOI:
10.1016/j.jclepro.2020.124281

11. Quantifying and Evaluating the Cultivated Areas Suitable for Fallow in Chongqing of China Using Multisource Data

Author:
Li, Yuanqing; Shi, Kaifang; Wang, Yahui; Yang, Qingyuan
Source:
Land 2021 v.10 no.1
ISSN:
2073-445X
Subject:
population density,   etc   ; fallow; karsts; quantitative analysis; transportation; China;     Show all 6 Subjects
Abstract:
... The quantitative evaluation of the suitability of land fallow is of great significance to the effective implementation of fallow system in rural China. The purpose of this study is to systematically evaluate the cultivated areas suitable for fallow in Chongqing, China. The results show that: (1) a comprehensive index of cultivated land fallow (ILF) was developed by employing a series of multi—sour ...
DOI:
10.3390/land10010074

12. Environmental conditions modulate compensatory effects of site dependence in a food‐caching passerine

Author:
Sutton, Alex O.; Strickland, Dan; Freeman, Nikole E.; Norris, D. Ryan
Source:
Ecology 2021 v.102 no.1 pp. e03203
ISSN:
0012-9658
Subject:
population density,   etc   ; Passeriformes; fecundity; territoriality; wild animals; Ontario;     Show all 6 Subjects
Abstract:
... Although density regulates the abundance of most wild animal populations by influencing vital rates, such as fecundity and survival, the mechanisms responsible for generating negative density dependence are unclear for many species. Site dependence occurs when there is preferential filling of high‐quality territories, which results in higher per capita vital rates at low densities because a larger ...
DOI:
10.1002/ecy.3203

13. Waste services' performance assessment: The case of Tuscany, Italy

Author:
Romano, Giulia; Ferreira, Diogo Cunha; Marques, Rui Cunha; Carosi, Laura
Source:
Waste management 2020 v.118 pp. 573-584
ISSN:
0956-053X
Subject:
population density,   etc   ; ownership; privatization; Italy;     Show all 4 Subjects
Abstract:
... This paper assesses the performance of waste services in the region of Tuscany in Italy. It adopts non-parametric techniques for this purpose. Furthermore, it investigates the influence of the operational environment on the estimated performance by using the robust order-m technique. Meaningful levels of inefficiency were found in the Italian waste services. A specification of the ownership of the ...
DOI:
10.1016/j.wasman.2020.08.057

14. Regional occurrence of perfluoroalkane substances in human milk for the global monitoring plan under the Stockholm Convention on Persistent Organic Pollutants during 2016–2019

Author:
Fiedler, Heidelore; Sadia, Mohammad
Source:
Chemosphere 2021 v.277 pp. 130287
ISSN:
0045-6535
Subject:
population density,   etc   ; breast milk; carboxylic acids; perfluorohexane sulfonic acid; perfluorooctane sulfonic acid; statistical analysis; Sweden;     Show all 7 Subjects
Abstract:
... The human milk monitoring component of the global monitoring plan under the Stockholm Convention on Persistent Organic Pollutants was implemented from 2016 to 2019 and had 44 human milk samples from primiparae collected in 42 countries and analyzed for perfluoroalkane substances (PFAS), at the MTM Research Centre at Örebro University, Sweden. The targeted compounds were restricted to the two liste ...
DOI:
10.1016/j.chemosphere.2021.130287

15. Occurrence, health risk assessment and regional impact of parent, halogenated and oxygenated polycyclic aromatic hydrocarbons in tap water

Author:
Liu, Quanzhen; Xu, Xiong; Lin, Lihua; Yang, Guang; Wang, Donghong
Source:
Journal of hazardous materials 2021 v.413 pp. 125360
ISSN:
0304-3894
Subject:
population density,   etc   ; bromination; health effects assessments; people; risk; tap water; China;     Show all 7 Subjects
Abstract:
... Recently, derivates of parent polycyclic aromatic hydrocarbons (PAHs) have aroused increasing concerns due to potential health problems they cause. In this study, we first found the coexistence of PAHs, chlorinated PAHs (Cl-PAHs), brominated PAHs (Br-PAHs) and oxygenated PAHs (OPAHs) in tap water. Twenty-six compounds including 13 PAHs, 5 Cl-PAHs, 5 Br-PAHs, and 3 OPAHs were detected. Total concen ...
DOI:
10.1016/j.jhazmat.2021.125360

16. Variation of population density on a beach: A simple analytical formulation

Author:
Dragani, Walter; Bacino, Guido; Alonso, Guadalupe
Source:
Ocean & coastal management 2021 v.208 pp. 105589
ISSN:
0964-5691
Subject:
population density,   etc   ; Orthocoronavirinae; air temperature; coastal zone management; pandemic; people; sea level; summer; tourism; viruses; Argentina;     Show all 11 Subjects
Abstract:
... Since the novel coronavirus was reported (December 2019), the virus spread rapidly breaking through frontiers and impacting almost all countries of the world. Tourism is one of the sectors that has been heavily affected by the crisis. Even though there are several protocols for tourism activities that were written for the austral summer season, at the present, physical distancing is considered an ...
DOI:
10.1016/j.ocecoaman.2021.105589

17. Urban growth pattern and commuting efficiency: Empirical evidence from 100 Chinese cities

Author:
Rao, Yingxue; Yang, Jixin; Dai, Deyi; Wu, Kaisong; He, Qingsong
Source:
Journal of cleaner production 2021 v.302 pp. 126994
ISSN:
0959-6526
Subject:
population density,   etc   ; empirical research; landscapes; models; ownership; people; socioeconomics; standard deviation; urbanization; China;     Show all 10 Subjects
Abstract:
... With the intensification of urbanization, the improvement of commuting efficiency from an urban form optimization perspective has increasingly attracted scholars’ attention. This study used the spatial lag model and the spatial error model to investigate China’s 100 most congested cities. The main innovation is the introduction of the urban growth pattern (UGP) and how urban form is associated wit ...
DOI:
10.1016/j.jclepro.2021.126994

18. Geographical distribution of Aralia elata characteristics correlated with topography and forest structure in Heilongjiang and Jilin Provinces, Northeast China

Author:
Wei, Hongxu; Chen, Guoshuang; Chen, Xin; Zhao, Hengtian
Source:
Journal of forestry research 2021 v.32 no.3 pp. 1115-1125
ISSN:
1007-662X
Subject:
population density,   etc   ; Aralia elata; altitude; forestry; forests; geographical distribution; latitude; leaf mass; longitude; research; understory; China;     Show all 12 Subjects
Abstract:
... The Araliaceae family consists of numerous species of medical plants of significant value as non-wood forest products. To conserve and culture these plants in natural forest stands is an important undertaking which should be implemented according to the relationship between forest structure and understory population. In this study, thirty-five plots were established in natural Aralia elata stands. ...
DOI:
10.1007/s11676-020-01100-2

19. Microplastic in atmospheric fallouts of a developing Southeast Asian megacity under tropical climate

Author:
Truong, Tran-Nguyen-Sang; Strady, Emilie; Kieu-Le, Thuy-Chung; Tran, Quoc-Viet; Le, Thi-Minh-Tam; Thuong, Quoc-Thinh
Source:
Chemosphere 2021 v.272 pp. 129874
ISSN:
0045-6535
Subject:
population density,   etc   ; cities; land use; microplastics; occupations; rain; solid wastes; tropics; waste treatment; wind;     Show all 10 Subjects
Abstract:
... Microplastics in atmospheric fallouts from a developing megacity influenced by a tropical monsoon climate were investigated during a year. Three sites were selected according to the surrounding population density, the land use and occupation. The microplastic deposition fluxes varied between of 71–917 items m⁻² d⁻¹, for an observation size range of 300–5000 μm. Fibers predominated while fragments ...
DOI:
10.1016/j.chemosphere.2021.129874

20. Factors of ecosystem service values in a fast-developing region in China: Insights from the joint impacts of human activities and natural conditions

Author:
Liu, Zhitao; Wu, Rong; Chen, Yongxin; Fang, Chuanglin; Wang, Shaojian
Source:
Journal of cleaner production 2021 v.297 pp. 126588
ISSN:
0959-6526
Subject:
population density,   etc   ; ecosystem services; ecosystems; estuaries; humans; land use; rivers; statistics; sustainable development; urban areas; China;     Show all 11 Subjects
Abstract:
... Understanding the spatiotemporal variety and influencing mechanisms of ecosystem service value (ESV) can provide a scientific guide for the regional ecological management and sustainable development. However, the joint effect of factors influencing ESV is ignored, which is an important way for influencing factors to work in the complex and frequently interacting ecosystem. In this study, we used r ...
DOI:
10.1016/j.jclepro.2021.126588