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The impact of climate warming on world agricultural production and food security has become increasingly obvious. As an important source of carbon emissions and the carbon sink system, the green development of agriculture is one of the important ways to alleviate the crisis and achieve China' s goals of reaching peak carbon emissions and carbon neutrality. Exploiting the potential of agricultural carbon sinks and accurately calculating agricultural net carbon emissions are of great significance to promoting the green development of agriculture meeting the ' dual carbon' goals. Based on the dual characteristics of the agricultural carbon cycle, this paper sorted out the logical relationship between agricultural green development and the agricultural carbon cycle, incorporated the role of agricultural carbon sinks into the calculation framework of agricultural carbon emissions, and measured China' s agricultural net carbon emissions from 2000 to 2019 by time and region. The decoupling model of agricultural net carbon emissions from agricultural economic growth was constructed. The results of the study found that the total amount of carbon emissions from agricultural sources increased from 277.899 million t in 2000 to 308.383 1 million t in 2019, with an average annual growth rate of 0.52%, but the agricultural carbon emission intensity showed a trend of continuous decline; the agricultural carbon sink increased from 99.539 9 million t in 2000 to 133.039 million t in 2019, with an average annual growth rate of 1.46%, and the agricultural carbon sink resources were considerable. The intensity of agricultural carbon source emissions was higher in the west than in other regions and there was a clear gap with the eastern region. The total amount of agricultural carbon source emissions, carbon sinks, and net carbon emissions all showed a medium-high pattern. The decoupling relationship between agricultural economic growth and agricultural net carbon emissions was mainly manifested in two decoupling states: strong decoupling and weak decoupling. Nearly 50% of the provinces achieved the ideal strong decoupling state in terms of agricultural green development, while the remaining provinces were in a weak decoupling state, and the decoupling state was generally ideal. Finally, this paper puts forward targeted countermeasures and suggestions to promote the green development of agriculture and help achieve the ' dual carbon' goals: we should accurately locate the carbon source; ensure the ' double bottom line' of food security and pig production capacity under low-carbon agriculture; resolve the resource endowment differences between regions; explore the potential of the agricultural carbon trading market; create a new path for farmers to increase their income, maintain the strong and improve the weak; and strive to achieve the ' package' of strong decoupling in agriculture to help achieve the ' dual carbon' goals. [ABSTRACT FROM AUTHOR]

With global warming, heat stress has become one of the research hotspots in livestock industry. Heat stress has negative impacts on production performance and body welfare of dairy cattle in varying degrees, which not only reduces the feed intake and milk production performance, but also damages reproductive capacity and body immunity. The paper summarizes the harm of heat stress on dairy cattle in main aspects, and explains the nutritional managements for preventing and alleviating heat stress from the aspects of feed structure, feed additives, etc., as to reduce the negative impact of heat stress on dairy cattle. The article has great significance for improving milk production in high temperature season and improving milk quality. [ABSTRACT FROM AUTHOR]

As an important methane emission source, alpine wetland ecosystem contributes a great deal to global warming. Methanogen communities in wetlands play an important role in greenhouse gas emissions, and it is important to explore the response of methanogen community structure and diversity to temperature rise in alpine wetlands. This paper takes Qinghai Lake alpine wetland as the research object and adopts high-throughput sequencing method to carry out the research. Based on 97% sequence similarity clustering, the total number of OTU in the 10 soil samples is 602, and the unique number of OTU in the control and warming samples is 30 and 43, respectively. Compared with the control group, the warming treatment can not significantly change the diversity index and order level dominant flora of methanogens in the alpine wetland (P>0.05). The methanogens in the alpine wetland are all Euryarchaeota, and the order level is dominated by Methanomicrobiales (67.35%), Methanosarcinales (14.14%) and Methanobacteriales (10.21%). Lefse analysis showed that, after increasing the temperature, the relative abundance of Methanomassiliicoccus decreases significantly, while that of Candidatus Methanogranum increases significantly. On the whole, the composition and diversity of methanogen community in Qinghai Lake alpine wetland are relatively stable, and temperature increase has little effect on methanogen community, Methanomassiliicoccus and Candidatus Methanogranum are more sensitive to temperature change. [ABSTRACT FROM AUTHOR]

Petrocodon Hance is one of the famous ornamental flowers, but most of them are assessed as extremely dangerous (CR), or at least above vulnerable (VU) due to climate turbulence and strong interference of human activities. To reconstruct the temporal and spatial changes of the potential suitable areas of Petrocodon since the last interglacial period, and explore the response of the suitable areas to environmental changes, which provided theoretical guidance for the origin of Petrocodon, the study of geographical differentiation, the conservation of unique germplasm resources in China, and the development and utilization of gardens. In this paper, combined with 120 distribution records and 17 environmental variables, the optimal MaxEnt model and geographic information technology (ArcGIS) were used to simulate the suitable areas and distribution pattern of Petrocodon in China and Indo-China Peninsula. Based on stepwise multiple linear regression analysis, redundancy analysis and Monte-Carlo test, the dominant variables affecting the current geographical distribution of Petrocodon were evaluated. The results were as follows: (1) The prediction accuracy of the optimized MaxEnt model was high, and the AUC value was greater than 0.96. The potential suitable areas of Petrocodon for the present distribution are continuous from Southwest China to North Vietnam, scattered in central and southern China and blocky in North Myanmar, of which the South Yunnan-Guizhou Plateau in China was the most suitable. (2) The environmental variables which restrict the geographical distribution of Petrocodon included precipitation of the driest month (bio14), precipitation of the warmest quarter (bio18), precipitation of the wettest quarter (bio16), SD of the temperature seasonality (bio4), min temperature of the coldest month (bio6) and altitude (alt). (3) Under the climate change scenario, the expansion and contraction areas of the suitable habitat of Petrocodon were located in the north and northeast of the current potential distribution area, which were sensitive areas susceptible to climate change. During the last interglacial period, the suitable area of Petrocodon expanded on a large scale, but there was almost no suitable distribution area of Petrocodon in the dry and cold environment during the last glacial maximum. After that, with the aggravation of climate warming, the suitable habitats of Petrocodon increased rapidly to high latitudes, while the suitable habitat in low latitudes decreased. (4) The centroid position of the suitable area for Petrocodon migrated northwards from Yongfu County, Guangxi (110.10° E, 24.69° N) to Chengbu County, Hunan (110.29° E, 26.05° N). To sum up, global warming has a positive impact on the potential distribution area of Petrocodon, but extreme warming will cause the suitable habitat of Petrocodon to shrink, and the niche of Petrocodon will narrow. Southwest China to North Vietnam, which has the advantage of mature karst landform, may be its main refuge. [ABSTRACT FROM AUTHOR]

Climate warming has become the direction of future climate change. Climate warming and terrestrial ecosystem will interact and influence each other. Grassland ecosystem accounts for about 1/3 of land surface area. Observing and analyzing the responses of plant community and ecosystem carbon exchange in grasslands to climate warming will help to further predict changes in grassland ecosystem in the future. This paper reviewed the effects of climate warming on plant physiological and ecological processes, plant community and ecosystem carbon exchange of grasslands. Various results were obtained in different regions and by different experimental methods. Overall, climate warming had a positive effect on alpine grassland ecosystem, a negative effect on tropical grassland ecosystem, and positive/negative effects on temperate grassland ecosystem. In the future, long-term observational studies and mechanism studies on a global scale should be considered to further clarify the responses of grassland ecosystem to global warming. [ABSTRACT FROM AUTHOR]

With the increasing frequency of global warming and extreme weather, climate shocks have become a serious challenge for sustainability. The increase of residential income and the popularization of housing appliances enable residents change their energy consuming behaviors to adapt the adverse effects of climate shocks to improve living comfort. Thus, using temperature as a measure of climate shock, we evaluate how household energy consumption reacts to climatic shocks measured by cooling degree days, heating degree days and temperature intervals using panel data at city level in China. The results show that temperature changes have significantly altered household electricity consumption. 1℃ increase in annual cooling degree days and heating degree days leads to an increase of household electricity consumption by 20% and 8.5%, respectively, while the impacts on other energy types are not statistically significant. We found an asymmetric U-shaped relationship between temperature and household electricity consumption. Comparing to the 18～24°C, the impact of temperature increases on electricity consumption of summer is much larger than tempera-ture decreases in winter. It implies that global warming will have a net positive impact on electricity consumption, forming a positive feedback loop. The magnitude of response to electricity consumption on temperature changes shows a substantial heterogeneity over economic development and regional differences. This paper provides new insights for the demand-side management in the context of climate shocks, and enables government to make better informed policies in climate governance. [ABSTRACT FROM AUTHOR]