Comparison of Satellite and Ground-Based Phenology in China’s Temperate Monsoon Area

Continuous satellite datasets are widely used in tracking vegetation responses to climate variability. Start of season (SOS), for example, can be derived using a number of methods from the time series of satellite reflectance data; however, various methods often produce different SOS measures which limit the application of satellite data in phenological studies. Therefore, we employed five methods to estimate SOS from the Advanced Very High Resolution Radiometer (AVHRR)/normalized difference vegetation index (NDVI) dataset. Subsequently, we compared the SOS with the ground-based first leaf date (FLD) of 12 deciduous broadleaved plant species at 12 sites of the Chinese Phenological Observation Network (CPON). The results show that the latitudinal patterns of five satellite-derived SOS measures are similar to each other but different from the pattern of ground phenology. For individual methods, the variability of SOS time series is significantly different from ground phenology except for HANTS, Polyfit, and Midpoint methods. The SOS calculated using the Midpoint method showed significant correlations with ground phenophases most frequently (in 47.1% of cases). Using the SOS derived from the Midpoint method, significantly earlier trends in SOS were detected in 50.7% of the natural vegetation area from 1982 to 2006

Fusing hyperspectral imaging and electronic nose data to predict moisture content in Penaeus vannamei during solar drying

The control of moisture content (MC) is essential in the drying of shrimp, directly impacting its quality and shelf life. This study aimed to develop an accurate method for determining shrimp MC by integrating hyperspectral imaging (HSI) with electronic nose (E-nose) technology. We employed three different data fusion approaches: pixel-, feature-, and decision-fusion, to combine HSI and E nose data for the prediction of shrimp MC. We developed partial least squares regression (PLSR) models for each method and compared their performance in terms of prediction accuracy. The decision fusion approach outperformed the other methods, producing the highest determination coefficients for both calibration (0.9595) and validation sets (0.9448). Corresponding root-mean square errors were the lowest for the calibration set (0.0370) and validation set (0.0443), indicating high prediction precision. Additionally, this approach achieved a relative percent deviation of 3.94, the highest among the methods tested. The findings suggest that the decision fusion of HSI and E nose data through a PLSR model is an effective, accurate, and efficient method for evaluating shrimp MC. The demonstrated capability of this approach makes it a valuable tool for quality control and market monitoring of dried shrimp products

Association of spring phenological traits with phylogeny and adaptation to native climate in temperate plant species in Northeast China

The effects of climate change on plant phenology have been widely recognized around the world. However, the effect of plant internal factors (such as phylogeny) on the variations in phenology among plant species remains unclear. In this study, we investigated the phylogenetic conservatism in spring phenological traits using phylogenetic signal and evolutionary models, including Brownian motion (BM) model, Ornstein–Uhlenbeck (OU) model and white noise (WN) model, based on the phenological data of 48 temperate plant species in Northeast China. We also explored the relative contributions of phylogeny and adaptation to native climate (i.e., the climate in native range of species) to the variations in the phenological traits among species using phylogenetic eigenvector regression and variance partitioning analysis. The results showed thatspring phenological traits conformed to the OU model, indicating thatspring traits were phylogenetically conserved. The effect of phylogeny on flowering traits was stronger than that on leaf-out traits. Additionally, the adaptation to native climate contributed more to the variations in spring phenological traits among species than phylogeny, and adaptation to native climate explained more variations in leaf-out traits than in flowering traits. Our results suggested that the spring phenological traits were constrained by both phylogeny and adaptation to native climate. However, the adaptation to native climate had a stronger effect on the variations in phenological traits than phylogeny. Therefore, the degree of similarity in spring phenological traits across closely related species depends on the degree of similarity in the environmental conditions where these close relatives are distributed.This work was supported by the National Key R & D Program of China (No. 2018YFA0606102), the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDA19020303, No. XDA26010202), and the Natural Science Foundation of China (No. 41771056)

The Impact of a Terminal High Altitude Area Defense Incident on Tourism Risk Perception and Attitude Change of Chinese Tourists Traveling to South Korea

The crisis event, which is one of the factors that occur most frequently, affects the sustainable development of tourism. Aiming to investigate the impact of a terminal high altitude area defense (THAAD) incident on tourism risk perception, destination image, attitude change and behavior intention of Chinese citizens planning to travel to South Korea, a questionnaire survey was conducted among 1000 Chinese citizens. By using descriptive statistics, factor analysis, and a structural equation model on the survey data, the results showed that (1) tourist destination risk perception exerted a negative effect on tourism image, culture image, and stability image of the destination; (2) the risk perception of tourists on tourism destinations would lead to a change in tourism attitudes, as Chinese citizens who planned to travel to South Korea considered changing their tourist destinations due to the THAAD incident; and (3) the increased risk perception of tourists on destinations had negative effects on behavior intention. Chinese citizens’ intention to travel to Korea was reduced after the THAAD incident. This study is of great importance for the sustainable development of tourism between China and Korea and provided a reference for improving risk management strategy for a tourism destination

Impact of Climate Variability on Flowering Phenology and Its Implications for the Schedule of Blossom Festivals

Many tourism destinations characterized by spring blossom festivals (e.g., cherry blossom festival) became increasingly popular around the world. Usually, spring blossom festivals should be planned within the flowering period of specific ornamental plants. In the context of climate and phenological change, whether the administrators of tourism destinations had perceived and responded to the flowering phenological variability is still unknown. Using the data of climate, blossom festival dates (BFD) of three tourist attractions, and first flowering dates (FFD) of specific species in Beijing, China, we analyzed the flowering phenological response to temperature and the impact of FFDs on BFDs from 1989 to 2016. It was shown that the flowering time of ornamental plants varied significantly among years in response to temperature variability. The administrators of Beijing Botanical Garden and Yuyuantan Park determined peach BFD and cherry BFD based on their experience rather than FFD of corresponding plants. Therefore, the mismatch between BFD and FFD occurred frequently at these two locations. However, the administrator of Jingshan Park scheduled the peony BFD following the variance of FFD of tree peony. These results revealed the various perceptions of climate change impacts for stakeholders of blossom festivals

Comparison of Satellite and Ground-Based Phenology in China’s Temperate Monsoon Area

Continuous satellite datasets are widely used in tracking vegetation responses to climate variability. Start of season (SOS), for example, can be derived using a number of methods from the time series of satellite reflectance data; however, various methods often produce different SOS measures which limit the application of satellite data in phenological studies. Therefore, we employed five methods to estimate SOS from the Advanced Very High Resolution Radiometer (AVHRR)/normalized difference vegetation index (NDVI) dataset. Subsequently, we compared the SOS with the ground-based first leaf date (FLD) of 12 deciduous broadleaved plant species at 12 sites of the Chinese Phenological Observation Network (CPON). The results show that the latitudinal patterns of five satellite-derived SOS measures are similar to each other but different from the pattern of ground phenology. For individual methods, the variability of SOS time series is significantly different from ground phenology except for HANTS, Polyfit, and Midpoint methods. The SOS calculated using the Midpoint method showed significant correlations with ground phenophases most frequently (in 47.1% of cases). Using the SOS derived from the Midpoint method, significantly earlier trends in SOS were detected in 50.7% of the natural vegetation area from 1982 to 2006

Chinese Tourists’ Perception of the Tourism Image of North Korea Based on Text Data from Tourism Websites

A good tourism image can significantly enhance the travel willingness and experience of international tourists. Most related research focused on the tourism image perception of world-famous cities, but research on the tourism image of North Korea is insufficient. We extracted text data from travel notes and reviews on Chinese travel websites. Subsequently, we used text mining and semantic network analysis to investigate Chinese tourists’ perception of the tourism image of North Korea. The results of the semantic network analysis show that tourism in North Korea consisted mainly of visits to the main cities and famous scenic spots, always with tour guides. Changes in high-frequency words indicated that Chinese tourists’ interest in North Korea’s history has weakened in recent years, and their interest in scenic spots and tourism products has increased. The results of the iterative correlation convergence analysis show that the topics relevant to tourists’ image of North Korea are composed of representative scenic spots, the Korean War, Kaesong city, the Pyongyang City, people’s lives, and other notable experiences. This research makes an empirical case for the study of tourists’ perception of the tourism image of North Korea and provides targeted suggestions for the sustainable development of North Korean tourism

Characteristics of Spring Phenological Changes in China over the Past 50 Years

In order to understand past plant phenological responses to climate change in China (1963–2009), we conducted trends analysis of spring phenophases based on observation data at 33 sites from the Chinese Phenological Observation Network (CPON). The phenological data on first leaf date (FLD) and first flowering date (FFD) for five broad-leaved woody plants from 1963 to 2009 were analyzed. Since most phenological time series are discontinuous because of observation interruptions at certain period, we first interpolated phenological time series by using the optimal model between the spring warming (SW) model and the UniChill model to form continuous time series. Subsequently, by using regression analysis, we found that the spring phenophases of woody plants in China advanced at a mean rate of 0.18 days/year over the past 50 years. Changes of spring phenophases exhibited strong regional difference. The linear trends in spring phenophases were −0.18, −0.28, −0.21, −0.04, and −0.14 days/year for the Northeast China Plain, the North China Plain, the Middle-Lower Yangtze Plain, the Yunnan-Guizhou Plateau, and South China, respectively. The spatial differences in phenological trends can be attributed to regional climate change patterns in China