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Comparison of the water budget for the typical cropland and pear orchard ecosystems in the North China Plain Comparison of the water budget for the typical cropland and pear orchard ecosystems in the North China Plain

This dataset contains the grid data of the first leaf date (FLD) and first flower date (FFD) of six woody plants in Europe (34°57′N-72°3′N，25°3′W-40°3′E) from 1951 to 2021, with a spatial resolution of 0.1° and a temporal resolution of 1 day. The quality evaluation of the grid phenology data shows that the average error of FLD and FFD is 7.9 and 7.6 days respectively, which has high simulation accuracy.Method: Based on the in-situ phenology observations from the Pan European Phenology Project (PEP725) in the past 70 years, this dataset employed three phenology models (Unichill, Unified and Temporal-Spatial Coupling) to predict and upscale the phenology data on the continental scale, and developed a grid phenology dataset of woody plants in Europe.Dataset composition: The dataset contains the gridded phenology data of six woody plants in Europe from 1951 to 2021, including the spring FLD (BBCH11.zip) and the spring FFD (BBCH60.zip). The annual data of each species is stored as a Geotiff file with 651 row × 371 column. The data is named according to "year (YYYY) + species genus (Genus) + phenophase (_xx)". For example, "2021Aesculus_11. tif" is the grid data file of the FLD of European Aesculus in 2021. The unit of phenology data is Julian day of year (DOY), which represents the actual number of days from the date of phenology occurrence to January 1 of the current year. The valid value is 1-366, and the invalid filling value is 999. The spatial reference system of the data is EPSG:4326 (WGS84). This dataset contains the grid data of the first leaf date (FLD) and first flower date (FFD) of six woody plants in Europe (34°57′N-72°3′N，25°3′W-40°3′E) from 1951 to 2021, with a spatial resolution of 0.1° and a temporal resolution of 1 day. The quality evaluation of the grid phenology data shows that the average error of FLD and FFD is 7.9 and 7.6 days respectively, which has high simulation accuracy.Method: Based on the in-situ phenology observations from the Pan European Phenology Project (PEP725) in the past 70 years, this dataset employed three phenology models (Unichill, Unified and Temporal-Spatial Coupling) to predict and upscale the phenology data on the continental scale, and developed a grid phenology dataset of woody plants in Europe.Dataset composition: The dataset contains the gridded phenology data of six woody plants in Europe from 1951 to 2021, including the spring FLD (BBCH11.zip) and the spring FFD (BBCH60.zip). The annual data of each species is stored as a Geotiff file with 651 row × 371 column. The data is named according to "year (YYYY) + species genus (Genus) + phenophase (_xx)". For example, "2021Aesculus_11. tif" is the grid data file of the FLD of European Aesculus in 2021. The unit of phenology data is Julian day of year (DOY), which represents the actual number of days from the date of phenology occurrence to January 1 of the current year. The valid value is 1-366, and the invalid filling value is 999. The spatial reference system of the data is EPSG:4326 (WGS84).

Ethanol is a significant chemical feedstock, which can be employed not only as a raw material for chemicals and polymers, but also as an additive to petrol. It is typically produced in industry through either fermentation or ethylene hydration. In light of the growing demand for ethanol, it is imperative to investigate the potential of multi-channel production of ethanol. One-step ethanol production from syngas represents a significant method of ethanol production from non-fossil oil energy sources, and it is also an important means of clean utilization of coal. The cost of direct ethanol production from syngas is relatively low, but the distribution of alcohols with different carbon numbers in the alcohol product is wide, which makes subsequent separation difficult and restricts its large-scale development. Consequently, in the research of direct ethanol production from syngas, the key points to improve the process economics and promote the development of this technology are to improve the selectivity of ethanol and develop the efficient catalysts. Mo-based catalysts can be employed for low-hydrogen syngas. At the same time, it is challenging to deposit carbon, exhibits robust resistance to sulfur poisoning, and demonstrates excellent stability, which also extends the reaction cycle. However, the methanol content of the alcohol product is relatively high. Although the use of Fischer-Tropsch element modification can significantly reduce the methanol selectivity, it will inevitably lead to the problem of broadening the distribution of alcohols. In recent years, there has been a growing attention in the preparation of catalysts using non-thermal plasma technology. Non-thermal plasma comprises not only electrons, ions, molecules and free radicals, but also photons and excited substances. Previous studies have demonstrated that the non-thermal plasma method can induce alterations in the nucleation of the active phase and the crystal growth mode in the preparation of catalysts. Concurrently, for thermodynamically unfavorable reactions, the utilization of non-thermal plasma technology can disrupt the thermodynamic equilibrium limit, thereby facilitating the reaction. In this study, Mo-based oxide and sulfide composite catalysts were prepared from the precursor of molybdenum sulfide by two distinct methods: the conventional thermal method and the RF non-thermal plasma method. The catalytic performance of Mo-based oxide and sulfide composite catalysts for the synthesis of ethanol from syngas was then investigated. A range of analytical techniques were employed to investigate the physical and chemical properties of the molybdenum-based oxygen-sulfur complex catalysts synthesized by different preparation methods. These included XRD, UV-visible, HR-TEM, SEM, HAADF-STEM, XPS, CO-TPD, H2-TPD, CO2-TPD and In-situ DRIFTS. Moreover, the objective was also to ascertain the impact of the physical and chemical properties on the catalytic performance of the different catalysts. Among them, the MOS-P catalyst exhibited the best catalytic performance. Under the reaction conditions of 6 MPa, 320 ℃, and a space velocity of 4500 h-1, the CO conversion reached 22.5%. The selectivity of total alcohols was 71.4%, with ethanol accounting for 29.1% of the total alcohols. This research will provide theoretical guidance for the directional conversion of syngas and serves as a reference for the design and preparation of new molybdenum-based materials. Ethanol is a significant chemical feedstock, which can be employed not only as a raw material for chemicals and polymers, but also as an additive to petrol. It is typically produced in industry through either fermentation or ethylene hydration. In light of the growing demand for ethanol, it is imperative to investigate the potential of multi-channel production of ethanol. One-step ethanol production from syngas represents a significant method of ethanol production from non-fossil oil energy sources, and it is also an important means of clean utilization of coal. The cost of direct ethanol production from syngas is relatively low, but the distribution of alcohols with different carbon numbers in the alcohol product is wide, which makes subsequent separation difficult and restricts its large-scale development. Consequently, in the research of direct ethanol production from syngas, the key points to improve the process economics and promote the development of this technology are to improve the selectivity of ethanol and develop the efficient catalysts. Mo-based catalysts can be employed for low-hydrogen syngas. At the same time, it is challenging to deposit carbon, exhibits robust resistance to sulfur poisoning, and demonstrates excellent stability, which also extends the reaction cycle. However, the methanol content of the alcohol product is relatively high. Although the use of Fischer-Tropsch element modification can significantly reduce the methanol selectivity, it will inevitably lead to the problem of broadening the distribution of alcohols. In recent years, there has been a growing attention in the preparation of catalysts using non-thermal plasma technology. Non-thermal plasma comprises not only electrons, ions, molecules and free radicals, but also photons and excited substances. Previous studies have demonstrated that the non-thermal plasma method can induce alterations in the nucleation of the active phase and the crystal growth mode in the preparation of catalysts. Concurrently, for thermodynamically unfavorable reactions, the utilization of non-thermal plasma technology can disrupt the thermodynamic equilibrium limit, thereby facilitating the reaction. In this study, Mo-based oxide and sulfide composite catalysts were prepared from the precursor of molybdenum sulfide by two distinct methods: the conventional thermal method and the RF non-thermal plasma method. The catalytic performance of Mo-based oxide and sulfide composite catalysts for the synthesis of ethanol from syngas was then investigated. A range of analytical techniques were employed to investigate the physical and chemical properties of the molybdenum-based oxygen-sulfur complex catalysts synthesized by different preparation methods. These included XRD, UV-visible, HR-TEM, SEM, HAADF-STEM, XPS, CO-TPD, H2-TPD, CO2-TPD and In-situ DRIFTS. Moreover, the objective was also to ascertain the impact of the physical and chemical properties on the catalytic performance of the different catalysts. Among them, the MOS-P catalyst exhibited the best catalytic performance. Under the reaction conditions of 6 MPa, 320 ℃, and a space velocity of 4500 h-1, the CO conversion reached 22.5%. The selectivity of total alcohols was 71.4%, with ethanol accounting for 29.1% of the total alcohols. This research will provide theoretical guidance for the directional conversion of syngas and serves as a reference for the design and preparation of new molybdenum-based materials.

Janzen-Connell (JC) effects, hypothesized to be mostly driven by negative plant-soil feedbacks (PSFs), are considered to be the key mechanism that regulates tropical forest plant diversity and coexistence. However, intraspecific variation in JC effects may weaken this mechanism, with the strength of PSFs being a potentially key variable process. We conducted a manipulated experiment with seedlings from two populations of Pometia pinnata (Sapindaceae), a tropical tree species in southwest China. We aimed to measure the intraspecific difference in PSF magnitude caused by inoculating the soil from different P. pinnata source populations and growing seedlings under differing light intensity and water availability treatments, and at varying plant densities. We found negative PSFs for both populations with the inoculum soil originating from the same sites, but PSFs differed significantly with the inoculum soil from different sites. PSF strength responded differently to biotic and abiotic drivers; PSF strength was weaker in low moisture and high light treatments than in high moisture and low light treatments. Our study documents intraspecific variation in JC effects: specifically, P. pinnata have less defences to their natively-sourced soil, but are more defensive to the soil feedbacks from soil sourced from other populations. Our results imply that drought and light intensity tended to weaken JC effects, which may result in loss of species diversity with climate change. Janzen-Connell (JC) effects, hypothesized to be mostly driven by negative plant-soil feedbacks (PSFs), are considered to be the key mechanism that regulates tropical forest plant diversity and coexistence. However, intraspecific variation in JC effects may weaken this mechanism, with the strength of PSFs being a potentially key variable process. We conducted a manipulated experiment with seedlings from two populations of Pometia pinnata (Sapindaceae), a tropical tree species in southwest China. We aimed to measure the intraspecific difference in PSF magnitude caused by inoculating the soil from different P. pinnata source populations and growing seedlings under differing light intensity and water availability treatments, and at varying plant densities. We found negative PSFs for both populations with the inoculum soil originating from the same sites, but PSFs differed significantly with the inoculum soil from different sites. PSF strength responded differently to biotic and abiotic drivers; PSF strength was weaker in low moisture and high light treatments than in high moisture and low light treatments. Our study documents intraspecific variation in JC effects: specifically, P. pinnata have less defences to their natively-sourced soil, but are more defensive to the soil feedbacks from soil sourced from other populations. Our results imply that drought and light intensity tended to weaken JC effects, which may result in loss of species diversity with climate change.