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Bifunctional heterogeneous catalysts (HZ-ZrP) were prepared by using HZSM-5 as the carrier to support a zirconium phosphate (ZrP) active component for the one-pot value-added conversion of biomass-derived furfural (FAL). By changing the loading amount of ZrP, the ratio of Lewis to Brønsted acid (2.7–15.4) and the acid strength of the catalysts can be adjusted. HZ-ZrP-5 and HZ-ZrP-16 were selected for the production of different value-added chemicals, and a total yield of up to 93.8% (i-PL and GVL) and 64.2% (GVL) were obtained using isopropanol as the hydrogen donor under optimized conditions, respectively. Furthermore, stability and recyclability of the catalyst were also tested and showed no significant drop in total yield after recalcination. The catalysts have high activity (E a = 27.05 ± 3.08 kJ mol–1), but the ring-opening reaction restricted the cascade reaction. In addition, a possible reaction pathway and mechanism for the FAL conversion were proposed.

The spatial distribution and diversity of archaeal and bacterial ammonia oxidizers (AOA and AOB) were evaluated targeting amoA genes in the gradient of a littoral buffer zone which has been identified as a hot spot for N cycling. Here we found high spatial heterogeneity in the nitrification rate and abundance of ammonia oxidizers in the five sampling sites. The bacterial amoA gene was numerically dominant in most of the surface soil but decreased dramatically in deep layers. Higher nitrification potentials were detected in two sites near the land/water interface at 4.4-6.1 μg NO 2 − -N/(g dry weight soil·hr), while only 1.0-1.7 μg NO 2 − -N/(g dry weight soil·hr) was measured at other sites. The potential nitrification rates were proportional to the amoA gene abundance for AOB, but with no significant correlation with AOA. The NH 4 + concentration was the most determinative parameter for the abundance of AOB and potential nitrification rates in this study. Higher richness in the surface layer was found in the analysis of biodiversity. Phylogenetic analysis revealed that most of the bacterial amoA sequences in surface soil were affiliated with the genus of Nitrosopira while the archaeal sequences were almost equally affiliated with Candidatus 'Nitrososphaera gargensis' and Candidatus 'Nitrosocaldus yellowstonii'. The spatial distribution of AOA and AOB indicated that bacteria may play a more important role in nitrification in the littoral buffer zone of a N-rich lake.