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Soil food webs are extremely complex as they contain diverse organisms. Feeding preference, also known as prey selection, is an important determinant of soil community compositions. However, the feeding preferences of nematodes are commonly ignored in ecology research. In this paper, the population dynamics and feeding preferences of three bacterial-feeding nematodes (i.e., Caenorhabditis elegans, Protorhabditis spp., and Acrobeloides spp.) for eight bacterial prey species were evaluated. Protorhabditis and Acrobeloides were isolated from a paddy soil in subtropical China. C. elegans, the most common model system for biological research, was used as a control in this study, and it was revealed that C. elegans could feed on all the eight bacteria strains. Protorhabditis could only survive when fed E. coli and Bacillus thuringiensis. Acrobeloides could only survive when fed E. coli and B. aryabhattai. During 10 days of culture, C. elegans populations reached the maximum in 5–7 days, and most C. elegans populations exceeded 10,000 individuals. The two Protorhabditis populations on E. coli and Bacillus thuringiensis included less than 800 individuals during 10 days of culture. Acrobeloides population on B. aryabhattai reached the maximum (7799 individuals) on day 8, while on E. coli was its population included less than 500 individuals. These results indicate that different nematode species indeed have distinct feeding preferences. In addition, the population dynamics of the two soil nematodes isolated from soil could not fully match with their inferred life-history strategies (i.e., cp values, and a 1-5 colonizer-p-ersister series that range from r-strategists to K-strategists). Our findings highlights the existing deficiencies in the understanding of the feeding behavior and the life-history strategies of soil nematodes. [ABSTRACT FROM AUTHOR]

With the continuous promotion of China's electricity market reform, the introduction of competition in the power generation market provides a new research direction for the generation expansion planning (GEP) problem, which is of great significance in the promotion of the optimization of the power energy structure. In the context of marketization, the electricity price expectation during the planning period is a key factor of GEP for independent power generation groups. There is some literature showing that the electricity price expectation in the planning period can be estimated according to certain laws of market supply and demand, while it seems to us that a future Pay as Bid (PAB) mechanism is better to determine the electricity price expectation. In this paper, to explore the impact of these two different electricity price formation mechanisms on the evolution of the generation market, a multi-agent framework is first established to describe the interaction process among the generation market agents; then, a GEP model for independent power generation groups is developed in the market competition environment, and four representative scenarios are finally designed for detailed comparative studies. Based on these case studies, the conclusion can be summarized as: (1) the PAB bidding mechanism has a lower electricity price and higher market installed capacity almost all the time during the whole planning period for all four scenarios; (2) it is more important that PAB can reduce the impact of parameter uncertainty in the laws of market supply and demand, which can obtain more reliable and reasonable results regarding the long-term evolution of the generation market. [ABSTRACT FROM AUTHOR]

China has committed to ambitious targets to reduce its carbon emissions in the next decades, in order to combat climate change and improve the environment. The realization of the targets depends on the fair and effective mitigation plans of all provinces. However, with varying ecological and environmental conditions and social-economic development, it is a critical issue to quantify the provinces' efforts equally. This paper proposed a comprehensive fE index in coordinating ecology, equity and economy, by accounting for carbon emissions and sinks to characterize provincial carbon emission status in China, from 2000 to 2017, which shows a spatial pattern of "boundary high, central low". The provinces with higher fE value (>1.5) in boundary areas can be seen as "relative equality" provinces with good ecology circulation, equity and economic efficiency. The provinces with lower fE value (<0.7) in central areas around Bohai Bay are regarded as "severe inequality" provinces, and are identified as the hot-spot provinces, which have emitted more CO2 than their equity share by occupying the carbon emission space of other provinces in recent decades. These results could provide a reference for a provincial guide for carbon reduction and sustainable development of the low-carbon economy. [ABSTRACT FROM AUTHOR]