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Toxic Microcystis aeruginosa alters the resource allocation in Daphnia mitsukuri responding to fish predation cues
2021
Many prey organisms adaptively respond to predation risk by inducible defenses with underlying tradeoffs in resource allocation. Cyanobacterial blooms expose zooplankton to poor food conditions, affecting the herbivores’ fitness. Given the interferences on resources allocation and life history traits, poor-quality cyanobacteria are predicted to affect the adaptive predator-induced responses in zooplankton. Here, we exposed two clones (i.e., clones SH and ZJ) of the cladoceran Daphnia mitsukuri to different combinations of fish predation cues and diets containing toxic Microcystis aeruginosa (0%–30%). D. mitsukuri matured at a small size and had elongated relative tail spine as adaptive responses to fish cues. Despite the comparable tail spine defense, fish cue-induced changes in growth and reproduction in the clone SH were more pronounced than those in the clone ZJ under no M. aeruginosa. Animals accumulated microcystin in the whole body with increasing abundance of M. aeruginosa. However, the inducible enhanced tail spine allometry was not affected, resulting in unchanged tail spine defense by Daphnia under all M. aeruginosa treatments. By contrast, M. aeruginosa remarkably decreased the adaptive maturation size and the offspring number in all animals. However, the inducible reproductive effort tended to increase or remain unchanged depending on clones associated with the constant or decreased responses of the somatic growth effort under increasing M. aeruginosa. Our results suggested that toxic M. aeruginosa did not alter the resource allocation to antipredator morphological defense but affected the somatic growth and reproduction in D. mitsukuri under fish cues. The present study highlights the different effects of toxic cyanobacteria on adaptive predator-induced responses in zooplankton, promoting the understanding for the morphological defense-mediated predator–prey interactions in eutrophic environments.
Show more [+] Less [-]The burden of ambient air pollution on years of life lost in Wuxi, China, 2012–2015: A time-series study using a distributed lag non-linear model
2017
Zhu, Jingying | Zhang, Xuhui | Zhang, Xi | Dong, Mei | Wu, Jiamei | Dong, Yunqiu | Chen, Rong | Ding, Xinliang | Huang, Chunhua | Zhang, Qi | Zhou, Weijie
Ambient air pollution ranks high among the risk factors that increase the global burden of disease. Previous studies focused on assessing mortality risk and were sparsely performed in populous developing countries with deteriorating environments. We conducted a time-series study to evaluate the air pollution-associated years of life lost (YLL) and mortality risk and to identify potential modifiers relating to the season and demographic characteristics. Using linear (for YLL) and Poisson (for mortality) regression models and controlling for time-varying factors, we found that an interquartile range (IQR) increase in a three-day average cumulative (lag 0–2 day) concentrations of PM2.5, PM10, NO2 and SO2 corresponded to increases in YLL of 12.09 (95% confidence interval [CI]: 2.98–21.20), 13.69 (95% CI: 3.32–24.07), 26.95 (95% CI: 13.99–39.91) and 24.39 (95% CI: 8.62–40.15) years, respectively, and to percent increases in mortality of 1.34% (95% CI: 0.67–2.01%), 1.56% (95% CI: 0.80–2.33%), 3.36% (95% CI: 2.39–4.33%) and 2.39% (95% CI: 1.24–3.55%), respectively. Among the specific causes of death, cardiovascular and respiratory diseases were positively associated with gaseous pollutants (NO2 and SO2), and diabetes was positively correlated with NO2 (in terms of the mortality risk). The effects of air pollutants were more pronounced in the cool season than in the warm season. The elderly (>65 years) and females were more vulnerable to air pollution. Studying effect estimates and their modifications by using YLL to detect premature death should support implementing health risk assessments, identifying susceptible groups and guiding policy-making and resource allocation according to specific local conditions.
Show more [+] Less [-]Associations between short-term exposure to PM2.5 and stroke incidence and mortality in China: A case-crossover study and estimation of the burden
2021
Ban, Jie | Wang, Qing | Ma, Runmei | Zhang, Yingjian | Shi, Wangying | Zhang, Yayi | Chen, Chen | Sun, Qinghua | Wang, Yanwen | Guo, Xinbiao | Li, Tiantian
Stroke and fine particulate matter (PM₂.₅) are two important public health concerns worldwide. Although numerous studies have reported the associations between PM₂.₅ and stroke, scientific evidence in China is incomplete, particularly the effect of PM₂.₅ on the acute incidence and national acute health burdens of stroke attributed to PM₂.₅ pollution. This study identified about 131,947 registered patients and 23,018 deaths due to stroke in 10 counties located in various regions from 2013 to 2017. Using a time-stratified case-crossover design, this study evaluated the associations between short-term exposure to PM₂.₅ and the risks of acute incidence and mortality for different types of stroke on the same spatiotemporal scale. With a 10 μg/m³ increase in the PM₂.₅ concentration, the acute incidence risk increased by 0.37% (0.15%, 0.60%) for stroke, 0.46% (0.21%, 0.72%) for ischemic stroke, and −0.13% (−0.73%, 0.48%) for hemorrhagic stroke. The corresponding values for the mortality risk were 0.71% (0.08%, 1.33%), 1.09% (0.05%, 2.14%), and 0.43% (−0.44%, 1.31%) for stroke, ischemic stroke and hemorrhagic stroke, respectively. Compared with the other groups, females and patients aged over 64 years presented higher incidence and mortality risks, while the group aged >75 years may exhibit a greater risk of mortality. Based on the estimated effects, we evaluated 43,300 excess deaths and 48,800 acute incidences attributed to short-term PM₂.₅ exposure across China in 2015. This study provided robust estimates of PM₂.₅-induced stroke incidence and mortality risks, and susceptible populations were identified. Excess mortality and morbidity attributed to short-term PM₂.₅ exposure indicate the necessity to implement health care and prevention strategies, as well as medical resource allocation for noncommunicable diseases in regions with high levels of air pollution.
Show more [+] Less [-]The relationship between urban refuse with fecundity and nestlings' success of a generalist seabird in the Río de la Plata Estuary - Uruguay
2021
Lenzi, Javier | González-Bergonzoni, Iván | Flaherty, Elizabeth | Hernández, Daniel | Machín, Emanuel | Pijanowski, Bryan
Resource acquisition and allocation impacts individual fitness. Using pellet analysis of breeding adults and stable isotopes of carbon and nitrogen of down feathers of Kelp Gull (Larus dominicanus) nestlings, we evaluated the relationship between urban refuse (beef and chicken) and natural food (fish) consumption of individual females during the pre-incubation period, with fecundity and young nesting's success in the Río de la Plata Estuary in Uruguay. Assimilated urban refuse positively correlated with egg weight and negatively with young nestling's success. This suggests a possible impact of urban refuse foraged by females during the pre-incubation period on their immediate fecundity (positively) and young nestling's survival (negatively). Differences between studies at the individual and colony levels are also discussed in light of an “ecological fallacy” of interpretation and we thus argue for the need of additional research to evaluate this relationship further, considering potential confounding factors.
Show more [+] Less [-]Refined spatiotemporal analysis of drought characteristics under different characteristic variable matchings: a case study of the middle reaches of the Yellow River basin, China
2022
Li, Ying | Jia, Chenchen | Ma, Shuang | Hu, Zhentai | Sun, Jin
The refined assessment of the spatiotemporal characteristics of droughts is of great significance for drought evaluation. Based on monthly precipitation and temperature grid data (1961–2019) in the middle reaches of the Yellow River basin (MYRB), the standardized precipitation evapotranspiration index (SPEI) was calculated at monthly, seasonal, and annual scales. The run theory was used to extract the drought features at the monthly scale, and the spatiotemporal characteristics of different drought levels were analyzed using Mann–Kendall mutation tests and spatial interpolation. The Moran’ I was used to analyze the spatial heterogeneity of droughts. The results showed that the drought trend in the MYRB increased from 1961 to 2019, with the SPEI exhibiting an overall decreasing rate of − 0.1145/decade. Decreasing rates were observed in spring (− 0.1356/decade), summer (− 0.0362/decade), and autumn (− 0.0745/decade), whereas an increasing rate was observed in winter (0.0781/decade). Only extreme droughts were long term, with an intensity as low as − 22.29. The highest frequencies were observed for mild–moderate droughts, which mainly showed high-value clusters in the western and central regions. The frequencies of severe–extreme droughts mainly presented low-value clusters in the northern and southwestern areas. The frequencies of mild and severe droughts exhibited significant spatial cluster characteristics, while the drought intensity showed non-significant spatial clusters and a random distribution. The high and low values of drought intensity were mainly clustered in the middle–upper reaches. The research results provide reference for disaster prevention and mitigation, agricultural planning, and water resource allocation in the MYRB.
Show more [+] Less [-]Environmental governance effect of the transformation of export trade mode: empirical evidence from 194 cities in China
2022
Li, Guangqin | Fang, Xubing | Liu, Maotao
As one of the developing countries, China’s export trade mode (ETM) has gradually shifted from processing trade to general trade. Is the deterioration of China’s environmental pollution caused by the transformation of ETM? Based on the panel data from 194 cities in China from 2000 to 2016, this paper investigates the impact of ETM transformation on the environmental pollution and its internal mechanism. The results show that the ETM is gradually shifting from processing trade to general trade, and environmental pollution will deteriorate first and then improve, that is, showing a significant “inverted U-shaped” relationship between the transformation of ETM and environmental pollution. Through the robustness test of the threshold, and SYS-GMM model, the results are still valid. The mechanism research shows that the upgrading of industrial structure, energy structure, industrial agglomeration, environmental protection investment, and resource allocation are the main mechanisms that the transformation of ETM affects environmental pollution. The conclusions of this study can provide empirical evidence for the process that the environmental pollution level of developing countries deteriorated and then improved during the process of transforming from processing export trade to general export trade.
Show more [+] Less [-]Optimization of hyperconnected mobile modular production toward environmental and economic sustainability
2020
Fergani, Charifa | El Bouzekri El Idrissi, Adiba | Marcotte, Suzanne | Hajjaji, Abdelowahed
Logistics sustainability is increasingly becoming a central focus of businesses, when most societies are aware of the influence of industry on both the environment and human health. To address the drawbacks of the way logistics systems have been designed, a new logistics system called Physical Internet has been proposed. This system relies on the creation of hyperconnected logistics systems. It aims to improve in an order of magnitude the way physical objects are transported, handled, stored, supplied, realized, and used to be more sustainable and efficient economically, environmentally, and socially. This paper focuses on the product realization using a hyperconnected mobile production mode in the context of Physical Internet, an open global logistics system. It addresses its dynamic deployment of production modules and resource allocation and sharing. It then proposes a make-to-order bi-objective optimization model which minimizes costs and greenhouse gases (GHGs) related to the product realization of a manufacturer to serve its customers given the availability of the open fabs. Experimental results are presented to identify the computational performance of the established model, as well as the economic and environmental benefits of using the facilities enabled by the PI. Finally, it concludes and provides directions for future research.
Show more [+] Less [-]The body condition of invasive crayfish Faxonius limosus (Raf., 1817) (Decapoda: Cambaridae) is better in small rivers than in dam reservoirs in Central Europe
2022
BONK, Maciej | AMIROWICZ, Antoni
The impact of dam reservoirs on river ecosystems is one of the current major issues in hydrobiology. In addition to the impact on native biodiversity, impoundments may facilitate biological invasions. A successful invasion is presumably related to the individual life history and resource allocation strategy in expanding populations. We tested whether reservoirs affect the body condition of invasive Faxonius limosus in upland streams. We found positive allometry of growth in females but more frequent isometric growth in males, and the form factor a₃.₀ was significantly higher in males than in females within populations. Fulton’s condition factor (K) was calculated for standard carapace lengths of 20 mm (juvenile) and 40 mm (adult). Both mean KCL ₂₀ and KCL ₄₀ were higher in males than in females. Positive allometry of growth in females resulted in a larger mean KCL ₄₀ than KCL ₂₀. The majority of the mean K obtained in reservoirs was similar or lower than the respective condition in streams. The condition of adult females was higher in streams in comparison to reservoirs. The obtained results are in contrast to the hypothesis that reservoirs positively affect individual body conditions and show that these man-made lakes do not provide more favourable habitat conditions for F. limosus than those in the natural aquatic environments of an upland landscape. An advantageous effect of the presence of reservoirs on invasion spread may be possible in more ecologically harsh landscapes, especially in colder climatic zones. Our study is the first to investigate the relationship of the body condition of F. limosus in two contrasting habitats.
Show more [+] Less [-]The club convergence of green productivity across African countries
2022
Shen, Zhiyang | Shao, Anqi | Chen, Jiayi | Cai, Jinyang
This study investigates economic convergence and sustainable development in Africa. By introducing an aggregate production technology and directional distance function, it examines the productivity growth of 28 African economies from 1990 to 2019. The proposed approach considers all decision-making units (countries) as a whole, and the productivity gains are then estimated under a nonparametric framework. In the empirical analysis, the carbon emissions are included in the Luenberger productivity measurement, called green productivity. The results show that the annual average growth rate of green productivity is 1.51% in African, and different types of club convergence for green productivity indicator and its decomposition are observed during the sample period. The decomposition of the Luenberger indicator shows that green African growth is mainly driven by technological progress, not efficiency change. Furthermore, the overall inefficiency is decomposed into technical and structural effects. The latter measure the potential improvement in terms of resource reallocation. Structural inefficiency is larger than technical inefficiency, suggesting that African countries could improve their economic and environmental performances by optimizing input/output mixes.
Show more [+] Less [-]Digital economy development and haze pollution: evidence from China
2022
Che, Shuai | Wang, Jun
The development of the digital economy radiates to national ecological protection and resource utilization, holding the key to haze governance. However, as the largest developing country, the impact of China’s digital economy on haze pollution has received little attention. Based on the panel data of 275 prefecture-level cities in China from 2011 to 2018, this paper studies the impact and mechanism of digital economy development on haze pollution. The results of fixed effect model show that the development of digital economy has a significant negative impact on urban haze pollution in China. The results of heterogeneity analysis show that the development of digital economy has a more significant inhibitory effect on the haze pollution of resource-based cities, non-resource-based cities, eastern cities, and large cities. The quasi-natural experimental results show that the establishment of the “national big data comprehensive experimental area” is conducive to haze pollution control, which proves the conclusion that the digital economy can significantly reduce haze pollution. The development of digital economy can significantly reduce haze pollution by promoting technological innovation and optimizing resource allocation.
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