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Pineapple is the most important economic plant in the family Bromeliaceae and the third-most economically important tropical fruit in the world. It has become an important tropical fruit in Guangdong, Hainan, and Guangxi, which are suitable areas for its cultivation. However, modern and well-organized breeding systems have not yet been established for pineapple. In this review, we describe the current status of the geographical distribution, industrial development, and breeding of pineapple in China. The current status of pineapple breeding is introduced, including traditional breeding methods, such as crossbreeding, mutagenesis breeding, and biotechnology breeding, combining cell engineering and gene engineering. In addition, the research progress on assisted breeding technology based on genetic map construction and molecular marker development is presented. New challenges and perspectives for obtaining high fruit quality are discussed in the context of breeding programs for pineapple. [ABSTRACT FROM AUTHOR]

• Remote sensing data from 1962–2018 were used to analyze coastal lagoon–tidal inlet. • Four shoal-sandbar breaching and tidal-inlet migration events were observed. • A conceptual model for cyclic periodic evolution of ebb-tidal deltas was proposed. • The crucial factors of long-term and short-term in their evolution were discussed. • Remote sensing can be used for early warning of the evolution of ebb-tidal deltas. Coastal lagoon–tidal inlet systems occur worldwide, and each has its own unique evolution characteristics in relation to its geographical location, sediment characteristics, and tidal current and ocean wave conditions. However, insufficient observation data means that it is often difficult to fully understand the long-term and short-term evolution of ebb-tidal deltas, and it is even more difficult to monitor and warn against their evolution. This study uses long time-series remote sensing data for the period 1962–2018 to investigate the evolution of an ebb-tidal delta in Xincun Lagoon, Hainan Island, China. Four shoal-sandbar breaching and tidal-inlet migration events were observed, and the corresponding periodic variation characteristics of the ebb-tidal delta were documented. A conceptual model for the periodic evolution of ebb-tidal deltas was also proposed. The results showed that the long-period (15–20 years) evolution was controlled by the effects of seabed friction and tidal-scale lagoon resonance, while the changes in the length of the east sand-spit could be used as a significant early warning indicator for shoal-sandbar breaching and tidal-inlet migration events. In addition, both types of event were jointly triggered by typhoon storm-surges and the accompanying heavy rainfall, strong winds, and strong waves. Thus, the periodic evolution process of the ebb-tidal delta in Xincun Lagoon was determined to be a systematic process that is either controlled or influenced by a series of interconnecting factors. Moreover, we concluded that it is both feasible and valuable to establish a monitoring and early warning framework of ebb-tidal deltas through the use of time-series remote sensing images. The results of this study can improve the existing understanding of the processes and driving factors of periodic shoal-sandbar breaching and tidal-inlet migration, and can also increase safety nourishment for coastal lagoon–tidal inlet systems. [ABSTRACT FROM AUTHOR]

Combining geometric and optical methods based on a low-cost UAV platform can achieve high-resolution bathymetry mapping without ground-truth data in optically shallow water areas. However, with the increasing spatial resolution, water surface fluctuation interferes with the imaging. In this study, we propose a bathymetry mapping approach that combines video and geometric-optical principles. The multi-sampling of the video data allows for a temporal averaging window of each pixel. A motion-based frame registration method was developed to compose an image from a video acquired by UAV push-broom sampling to mitigate the instantaneous changes caused by water surface fluctuations. The composite images were used for bathymetry mapping using data from the photometric point clouds from the UAV images for calibration. Then, the improved effect of video multi-sampling on the optical bathymetric model was evaluated by comparing the results of bathymetric inversion based on single images and video composite images. An evaluation case in the coastal area of Hainan Island demonstrates that results based on composite images processed with three optical bathymetric models of different complexity increased the coefficient of determination from 0.8111, 0.8652, 0.9255 to 0.8652, 0.8750, 0.9363, and reduced the root mean square error from 0.234 m, 0.192 m, 0.143 m to 0.197 m, 0.178 m, 0.133 m, respectively. Qualitatively, using composite images from aerial RGB videos for bathymetry mapping effectively removes radiative anomalies due to wave focusing or reflection and provides a more accurate description of underwater objects' shape than single images. • A video-geometric-optical method can map shallow water in high resolution. • A motion-based frame registration method enables efficient large-area water mapping. • Video composite images on various models reduce the impact of wave fluctuations. • Nonlinear models can help to overcome the limited spectral information of RGB data. [ABSTRACT FROM AUTHOR]