Traffic Signal Timing Optimization Model Based on Video Surveillance Data and Snake Optimization Algorithm.

With the continued rapid growth of urban areas, problems such as traffic congestion and environmental pollution have become increasingly common. Alleviating these problems involves addressing signal timing optimization and control, which are critical components of urban traffic management. In this paper, a VISSIM simulation-based traffic signal timing optimization model is proposed with the aim of addressing these urban traffic congestion issues. The proposed model uses the YOLO-X model to obtain road information from video surveillance data and predicts future traffic flow using the long short-term memory (LSTM) model. The model was optimized using the snake optimization (SO) algorithm. The effectiveness of the model was verified by applying this method through an empirical example, which shows that the model can provide an improved signal timing scheme compared to the fixed timing scheme, with a decrease of 23.34% in the current period. This study provides a feasible approach for the research of signal timing optimization processes.

Habitat quality assessment provides indicators for socio-ecological management: a case study of the Chinese Loess Plateau.

The impact of changing land use and land cover (LULC) on regional habitat quality have attracted extensive attention. The Loess Plateau is an ecologically fragile area; LULC changes in this region have complex impacts on habitat quality at multiple spatiotemporal scales. This study developed an integrated assessment method based on multi-source data to assess habitat quality changes in the Loess Plateau during recent years (2000-2015) and in the future (2015-2050) under four typical scenarios. A significant increase in urban land use was observed on the Loess Plateau from 2000 to 2050, which resulted in a continuous decrease in the cropland area. The area of forest and grassland landscapes was also reduced by both urban and cropland expansion, with the most significant loss in the grasslands. A future overall decreasing trend in overall habitat quality is predicted, but the SSP1-2.6 scenario is significantly better than the SSP5-8.5 scenario. Urban expansion contributes a rapidly increasing proportion of habitat quality decline on the Loess Plateau; urban land will become the most significant threat to regional habitat quality by 2030. Policies for socio-ecological protection with clear, high-level objectives can effectively promote habitat quality. It is recommended that national nature reserves be delineated and ecological functions in the study area be continuously monitored. This research provides a potential socio-ecological baseline and implementation strategy for the habitat conservation-oriented management of large and fragile ecological regions.

Analysis of sustainable utilization of water resources based on the improved water resources ecological footprint model: A case study of Hubei Province, China.

Sustainable utilization of water resources has become a crucial topic worldwide. Study of the water resources ecological footprint (WEF) has important theoretical and practical significance for the management and optimal allocation of water resources. The current WEF model does not consider the differences between regions because it uses uniform equalization and yield factors. In this study, an improved WEF model is proposed by taking into account the regional characteristics of those two factors and provides results reflecting the consumption and supply of water resources more accurately. Taking Hubei Province, China, as an example, this study calculated the WEF per capita, the water resources ecological carrying capacity (WEC) per capita and the water resources ecological pressure index (WEPI) of each city in 2005, 2010 and 2015, and analysed the spatiotemporal patterns of water utilization. The results from the improved model show that the productive capacity of water resources in Hubei Province is gradually increasing and its pattern changed from a circular pattern with a higher edge and a lower centre to a ladder pattern that is higher in the southeast and lower in the northwest. In addition, the WEF and the WEC per capita show overall upward trends. Due to the differences at different urbanization levels and in the proportions of primary and secondary industries, the water resources pressure is greater in the east Hubei than that in the west. The western canyon region exhibits relatively higher sustainability of the utilization of water resources than the Jianghan Plain.

Crop production on the Chinese Loess Plateau under 1.5 and 2.0 °C global warming scenarios.

Global warming is a crucial factor affecting crop production in ecologically vulnerable areas. Warming-induced changes in the yields of different crops could pose significant challenges to food security and sustainability assessment. In this study, the World Food Studies model and a remote sensing product assimilation algorithm were used to develop a spatially explicit crop assimilation model applicable to the Loess Plateau of China. The model was used to simulate potential changes in actual yields and yield gaps for winter wheat and maize under three typical climate scenarios (Representative Concentration Pathways (RCPs): RCP 2.6, RCP 4.5, and RCP 8.5) from 2016 to 2060. Average yields increased in both winter wheat (2.38 %-4.96 %) and maize (5.41 %-6.85 %), with maize (RCP 4.5 > RCP 8.5 > RCP 2.6) more adapted to climate warming than winter wheat (RCP 2.6 > RCP 8.5 > RCP 4.5) in terms of yield increase rate. The yield increase and yield gap for winter wheat decreased most significantly in RCP2.6 (-2.28 %). Maize yield did not exceed 80 % of the potential yield in any scenario. The average phenological periods for winter wheat and maize are predicted be 2-4 and 9-16 days earlier, respectively. Crop yields were negatively correlated with radiation and yield gaps were positively correlated with precipitation. Future climate change will likely cause dramatic interannual crop yield fluctuations. Winter wheat is predicted to experience yield stagnation after 2050, whereas maize production potential will increase briefly before experiencing a long-term decline in growth. The results of this multi-scenario simulation assessment of crop production provide scientific support for implementing climate-adapted crop management strategies and integrated dry-crop-irrigated agriculture to meet food security objectives in this ecologically fragile area. We recommend integrated management measures to ensure regional food security through crop variety improvement, irrigation regulation, and planting structure optimization.

Spatial Characteristics of Coronavirus Disease 2019 and Their Possible Relationship With Environmental and Meteorological Factors in Hubei Province, China.

As of July 27, 2020, COVID-19 has caused 640,000 deaths worldwide and has had a major impact on people's productivity and lives. Analyzing the spatial distribution characteristics of COVID-19 cases and their relationships with meteorological and environmental factors might help enrich our knowledge of virus transmission and formulate reasonable epidemic prevention strategies. Taking the cumulative confirmed cases in Hubei province from January 23, 2020, to April 8, 2020, as an example, this study analyzed the spatial evolution characteristics of confirmed COVID-19 cases in Hubei province using exploratory spatial data analysis and explored the spatial relationship between the main environmental and meteorological factors and confirmed COVID-19 cases using a geographically weighted regression (GWR) model. Results show that there was no obvious spatial clustering of confirmed COVID-19 cases in Hubei province, while the decline and end of the newly confirmed cases revealed relatively obvious negative spatial correlations. Due to the lockdown in Hubei province, the main air quality indexes (e.g., AQI and PM2.5) decreased significantly and environmental quality was better than historical contemporaneous levels. Meanwhile, the results of the GWR model suggest that the impacts of environmental and meteorological factors on the development of COVID-19 were not significant. These findings indicate that measures such as social distancing and isolation played the primary role in controlling the development of the COVID-19 epidemic.

Integrating the SD-CLUE-S and InVEST models into assessment of oasis carbon storage in northwestern China.

Spatio-temporal integrated assessment of land-use change impacts on carbon storage services is a new and important research field in land science and landscape ecology. The objective of this paper is to use an integrated SD-CLUE-S and InVEST model to simulate and predict land-use changes impacts during 2000-2018 on carbon storage at pixel and regional scales in the Zhangye oasis, Northwest China. The SD-CLUE-S model was used to simulate land-use change, and three land-use scenarios (current trend, moderate protection, and strict protection) were defined in collaboration with oasis socioeconomic development and ecological environment conservation by local government. The InVEST model was then used to simulate land-use change impacts on carbon storage at different scales in the oasis. The results showed that: (1) the effects of built-up land expansion were especially notable, with a rapid decrease in cropland during 2009-2018; (2) the strict protection scenario saved the largest amount of carbon storage for the oasis compared with the current trend and moderate protection scenarios. The scientific value of this study has been to show that the proposed modeling method can be used to reflect different land-use patterns and their effects on ecosystem services at multiple scales in the oasis. Furthermore, this research can be used to help government managers encourage stakeholders to contribute funds and strategies to maintain oasis landscape patterns and ecological processes by implementing local plans for potential conservation projects.