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As an important foundation for promoting social progress and economic development, natural resources play an important role in the sustainable development of cities. However, the increasing demand of human beings for natural resources has led to various ecological environmental problems, such as excessive population density, serious environmental pollution, the continuous decline of total natural resources and per capita resources, all of which have hindered sustainable development. Therefore, the study of natural resources and sustainable development has become the focus of many current scholars. In this paper, CiteSpace is used as an analysis tool to analyze the literature on natural resources and sustainable development over the past 20 years. First of all, this paper deeply analyzes the research status of this field in terms of academic research trends, authors and research institutions, co-occurrence of keywords, etc., and on this basis, it then deeply analyzes its evolutionary path and research hot spots in the past 20 years through keyword emergence. Finally, according to the visualization of the analysis results, the future development trends of this research field are speculated: (1) Grasp the current research focus; (2) Improve the research accuracy; (3) Enrich the theoretical system of research; and (4) Establish an interdisciplinary research system.

To clarify feasibility of using combinations of imazapic and prometryn to control weeds in peanut field, their interaction effect was evaluated in greenhouse and verified in field. The results of pot experiments showed that the interaction of imazapic at 32 g a.i. ha−1 and prometryn at 400–850 g a.i. ha−1 exhibited synergistic effects for the control of Chenopodium album L., Portulaca oleracea L. and Digitaria sanguinalis (L.) Scop., and that the observed response (E0) was significantly greater than that expected (E). The combination of imazapic at 52 g a.i. ha−1 and prometryn at 400–850 g a.i. ha−1 also had synergistic effects on the control of Echinochloa crus-galli (L.) Beauv., and the E0 value was significantly greater than the E value. Field experiment demonstrated that imazapic plus prometryn at 32 + 850 g a.i. ha-1 or 52 + 400 g a.i. ha-1 exhibited better weed density suppression (93.2% or 95.1%), which was significantly higher than imazapic (85.0%) and prometryn (71.8%) applied at 90 g a.i. ha−1 and 950 g a.i. ha−1, respectively. The combinations showed superior weed fresh weight control than when they were applied alone. Comparing with s-metolachlor, the mixtures also provided significantly higher control of weed density and fresh weight under field condition. The mixtures were safe for peanut. These findings indicate that PRE application of combinations of imazapic and prometryn has great potential for weed control in peanut fields in China and that recommended field doses of imazapic plus prometryn are 32 + 850 or 52 + 400 g a.i. ha−1.

Lactobacillus brevis alcohol dehydrogenase (Lb-ADH) catalyzes reduction of prochiral carbonyl compounds to chiral alcohol and meanwhile consumes its cofactor NADH into NAD(+), while the cofactor regeneration can be catalyzed by Candida boidinii formate dehydrogenase (Cb-FDH). This work presents three different Escherichia coli whole-cell biocatalyst systems expressing recombinant ADH/FDH, FDH-LIN1-ADH and FDH-LIN2-ADH, respectively, all of which display very high efficacies of prochiral carbonyl conversion with respect to conversion rates and enantiomeric excess values. ADH/FDH represents co-expression of Lb-ADH and Cb-FDH under different promoters in a single vector. Fusion of Lb-ADH and Cb-FDH by a linker peptide LIN1 (GGGGS)₂ or LIN2 (EAAAK)₂ generates the two bifunctional enzymes FDH-LIN1-ADH and FDH-LIN2-ADH, which enable efficient asymmetric reduction of prochiral ketones in whole-cell biotransformation.