The role of technological innovation (TI) in green development is controversial. Based on 2003–2017 panel data of 108 cities in the Yangtze River Economic Belt (YREB), this study constructed an index system to evaluate urban green development and analyzed the role of TI on urban green development with the help of a panel econometric model. The results show that: (1) From 2003 to 2017, the levels of TI and green development of cities in the YREB have gradually improved, but the core–periphery structure is obvious, and the levels of TI and green development in the lower reaches are significantly higher than those in the middle and upper reaches. (2) TI has a significant positive role in promoting green development, showing a U-shaped nonlinear relationship, and this relationship varies from region to region. (3) TI has a significant impact on green development with direct and indirect effects. In the economic and social dimensions, TI has a positive impact on green development, while in the ecological dimension, the direct effect and indirect effect have opposite relationships. (4) TI has a significant threshold effect on green development, and there are differences in threshold characteristics between the three dimensions. These findings provide a scientific basis for policymaking about innovation-driven regional green development, and it can enrich the related theories of environmental economic geography.

The role of trade fairs in local innovation knowledge networks is studied by combining data on co-patenting networks in the Shanghai equipment manufacturing (machinery) industry with data from the Shanghai Metalworking and CNC Machine Tool Show (MWCS). Three propositions are developed, suggesting that: (1) local firms attending the MWCS are more research and development intensive than other firms; (2) trade fair attendees are linked with each other more closely in co-patenting networks than non-attendees; and (3) participating firms have more local co-patenting linkages than non-participating firms. The results largely support these propositions, confirming that participation in flagship fairs is associated with strong integration in innovation knowledge networks.

Despite China's rapid economic growth and embedding into global value chains, not much is known about the primary places where buyers and sellers from China and abroad meet, do business, and circulate information and knowledge: That is, the national/international trade fairs in the country. Previous reports suggest that the number and size of such events in China is growing and that the trade fair business is in the process of catching up. Under these circumstances, trade fairs may develop into import or export events, where buyers and sellers engage in transactions, or into temporary clusters, where they exchange knowledge for industrial upgrading and innovation. In this context this paper explores the interaction and communication patterns of firms at Chinese trade fairs and investigates whether these events are similar to those in Europe and North America. The analysis involves systematic comparison of the communication and interaction practices at three national/international trade fairs in Shanghai and Chengdu, based on a total of 102 semistructured interviews.

Under the controversial background of “Northwestern China is gradually developing towards warm and humid”, how hydrological drought responds to meteorological drought at the endorheic basin is of great significance. To address this problem, we first analyzed the spatiotemporal variation of meteorological and hydrological droughts at Tarim Basin River from 1960 to 2014 by using the daily standardized precipitation index (SPI) and daily standardized terrestrial water storage index (SWSI) based on the reanalysis data. Thereafter, we explored the spatiotemporal response of hydrological drought to meteorological drought on the multi-time scale by using the cross-wavelet transform method, Ensemble Empirical Mode Decomposition (EEMD), and correlation analysis. We find that: (1) both meteorological and hydrological droughts signified a gradually weakened trend in time; (2) meteorological and hydrological drought have significant resonance periods on the 10-month time scale and the 8-year time scale; (3) hydrological drought generally lags behind the meteorological drought by 7 days in plains areas, while it can last as long as several months or even a year in mountainous areas.