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1

H2 and syngas production from catalytic cracking of pig manure and compost pyrolysis vapor over Ni-based catalysts

Li W., Ren J., Zhao X.-Y., Takarada T.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 3

8--14

EN

Catalytic cracking of volatiles derived from wet pig manure (WPM), dried pig manure and their compost was investigated over Ni/Al2O3 and Ni-loaded on lignite char (Ni/C). Non-catalytic pyrolysis of WPM resulted in a carbon conversion of 43.3% and 18.5% in heavy tar and light tar, respectively. No tar was formed when Ni/Al2O3 was introduced for WPM gasification and the gas yield significantly reached to a high value of 64.4 mmol/g at 650°C. When Ni/C was employed, 5.9% of carbon in the light tar was found at 650°C, revealing that the Ni/C is not active enough for cracking of tarry materials. The pyrolysis vapor was cracked completely and gave a H2-rich tar free syngas in high yield. High water amount of WPM promotes steam gasification of char support, causing the deactivation of Ni/C. Such a study may be beneficial to the development of livestock manure catalytic gasification technology.

2

Variations of Leaf Economic Spectrum of Eight Dominant Plant Species in Two Successional Stages Under Contrasting Nutrient Supply

Mao W., Li Y.-L., Zhao X.-Y., Zhang T.-H., Liu X.-P.

Polish Journal of Ecology

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2016

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Vol. 64, nr 1

14--24

EN

Leaf functional traits are indicators of both plant community and ecosystem responses to environmental factors and can thus increase our capacity to understand ecosystem processes and community assembly due to climate change. The variation in leaf functional traits between succession stages in Horqin Sandy Land is caused by soil nutrient content and by intrinsic biological characteristic of species, but the effects are different. Leaf economic spectra were assessed for seven leaf traits of eight species from early and advanced stages of succession. Species from early succession stages are Agriophyllum squarrosum (L.) Moq., Corispermum macrocarpum Bge., Setaria viridis (L.) Beauv. and Pennisetum centrasiaticum Tzvel., and species from advanced successional stages are Chenopodium acuminatum Willd., Chloris virgate Swartz, Digitaria sanguinalis (L.) Scop. and Leymus secalinus (Georgi) Tzvel. All these species were grown in a greenhouse experiment under two contrasting nutrient supplies including high nutrient level (N+, with 20 g of nutrient addition) and low nutrient level (N-, with no added nutrients). As expected, the resource uptake strategies of the species were affected by soil fertilization addition. Leaf nitrogen content (LNC), leaf phosphorus content (LPC), and photosynthetic capacity per unit leaf area (Aarea) significantly increased at high nutrient level but LPC is more dramatically changed than others leaf traits. Leaf life span (LLS) and specific leaf area (SLA) did not show similar tendency with succession stage. At the same nutrient level, LES still shows different pattern between the early and the advanced succession stages. Species from early succession stages have higher LPC and Aarea, compared to species from advanced stages. Species from early succession stage also tend to have higher SLA and higher LNC than at the advanced succession stage. The LLS did not show any clear changes with succession process. These results provide evidence that LES shift along the succession process is mainly caused by intrinsic biological characteristic of species.

3

Effects of land use/cover change in the desert oasis system on topsoil carbon and nitrogen (middle of Heihe River basin, China)

Niu R.-X., Zhao X.-Y., Liu J.-L., Qin Y.

Polish Journal of Ecology

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2013

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Vol. 61, nr 1

45--54

EN

Land use/cover change (LUCC) is one of the main factors that influence the terrestrial carbon (C) and nitrogen (N) cycle. We examined the effects of land use/cover change on topsoil C, N, and microbial biomass C, N (MBC, MBN) and their relationship with other soil properties in the middle of Heihe river basin along a land use change gradient of 100-year farmland, 27-year farmland, 33-year pine forest, 28-year poplar forest, and 21-year shrubland, as well as native desert from which all the above cultivated systems are converted. Results revealed that land use conversion from native desert to the above cultivated ecosystems not only changed the basic eco-hydrological factors of the soil, such as improving the soil moisture and field capacity, decreasing the pH and salinity, but also altered the nutrient factors, such as improving the concentrations of soil organic C (SOC), total N (TN), MBC, MBN, NO3--N and NH4+-N,. With the increase of cultivated years, land use conversion had an increasing impact on the C and N sequestration and soil nutrients stabilization.