ABSTRACT
The impact of global warming on the growth and development of natural vegetation is an important concern worldwide. Based on the data from the vegetation normalization index, daytime temperature (Tmax), nighttime temperature (Tmin), precipitation, and elevation from 1982 to 2015, we examined the day-night warming response of 42 types of natural vegetation in China. The results showed that both the temperature at day and night was significantly increased in the study area, with obvious asymmetry. The night warming was about 1.6 times as high as that at daytime. The Tmin was more conducive to vegetation growth than the Tmax. The proportion of vegetation types with positive relationship with Tmin was greater than the Tmax, with significant spatial difference. Subtropical vegetation accounted for 85.7% of vegetation with positive correlation with Tmax. The temperate alpine, mountainous, and desert vegetation responded more positively to Tmin. The increase of Tmin was not conducive to the growth and development of vegetation at high altitudes, while that of Tmax was the opposite. The correlations of vegetation growth with Tmax and Tmin were as follows: steppe > meadow > needleleaf forest > desert vegetation > broadleaf forest; meadow > desert vegetation > broadleaf forest > steppe > needleleaf forest.
Subject(s)
Forests , Global Warming , Plant Development , China , Plants , TemperatureABSTRACT
The sperm of Eriocheir sinensis has a cup-shaped nucleus that contains several mitochondria embedded at the opening of the cup. The acrosome vesicle also contains derivants of mitochondria. The mitochondria distribution pattern involves a decrease in the number and changes in the structure and transportation of these organelles. The decreased number of sperm mitochondria is achieved through autophagy or the ubiquitination pathway. Prohibitin (PHB), the mitochondria inner membrane protein, is an evolutionarily highly conserved protein, is closely associated with spermatogenesis and sperm quality control and is also a potential substrate of ubiquitination. However, whether PHB protein mediates the ubiquitination pathway of sperm mitochondria in crustacean animals remains poorly understood. In the present study, we revealed that PHB, a substrate of ubiquitin, participates in the ubiquitination and degradation of mitochondria during spermiogenesis in E. sinensis. To confirm this finding, we used shRNA interference to reduce PHB expression and an overexpression technique to increase PHB expression in vitro. The interference experiment showed that the reduced PHB expression directly affected the polyubiquitination level and mitochondria status, whereas PHB overexpression markedly increased the polyubiquitination level. In vitro experiments also showed that PHB and its ubiquitination decide the fate of mitochondria.
ABSTRACT
Based on the integrated model of emergy-ecological footprint approaches, the ecological security of Liaoning Province, a typical case for the old industrial area, was quantitatively evaluated from 2003 to 2012, followed by a scenario analysis on the development trend of the ecological secu-rity by employing the gray kinetic model. The results showed that, from 2003 to 2012, the value of emergy ecological-capacity per capita in Liaoning Province decreased from 3.13 hm2 to 3.07 hm2, while the emergy-ecological footprint increased from 13.88 hm2 to 21.96 hm2, which indicated that the ecological deficit existed in Liaoning Province and the situation was getting worse. The ecological pressure index increased from 4.43 to 7.16 during the studied period, and the alert level of ecological security changed from light to middle level. According to the development trend, the emergy ecological capacity per capita during 2013-2022 would correspondingly decrease from 3.04 hm2 to 2.98 hm2, while the emergy ecological footprint would increase from 22.72 hm2 to 35.87 hm2, the ecological pressure index would increase from 7.46 to 12.04, and the ecological deficit would keep increasing and the ecological security level would slide into slightly unsafe condition. The alert level of ecological security would turn to be middle or serious, suggesting the problems in ecological safety needed to be solved urgently.
