Arid Zone Research ›› 2023, Vol. 40 ›› Issue (7): 1075-1084.doi: 10.13866/j.azr.2023.07.05

• Land and Water Resources • Previous Articles     Next Articles

Research progress in non-rainfall water: A review

YUAN Ruiqiang(),Li Zejun   

  1. School of Environmental and Resource Sciences, Shanxi University, Taiyuan 030006, Shanxi, China
  • Received:2023-03-02 Revised:2023-05-23 Online:2023-07-15 Published:2023-08-01

Abstract:

In dry and semi-arid environments, non-rainfall water is crucial for water balance and ecology and enhances regional water intake. To preserve ecological equilibrium, non-rainfall water may be a crucial water supply. However, owing to the longer wetting period of leaves, non-rainfall water may also contribute to the spread of diseases. This work discusses the measurement and modeling methodologies of dew, fog, and water vapor adsorption, examines the research development of dew, fog, and water vapor adsorption, and does a dynamic analysis of bibliometric hot spots to enhance our knowledge on non-rainfall water. The findings indicate that there is a minor movement of non-rainfall water between the ground and the atmosphere. Utilizing unique condensers will result in significant condensation. Pyramid condensers are more effective in collecting dew than plane condensers. Since non-rainfall water exhibits clear temporal and geographical fluctuation, it is difficult to monitor in real-world settings, which restricts relevant research. The regional focus is on non-rainfall water research. Studies on fog water mostly concentrate on coastal and mountainous locations, whereas studies on dew primarily concentrate on the site scale in arid and semi-arid regions. Water vapor adsorption typically takes place on dry ground. A hub for research on non-rainfall water is the Negev Desert in southern Israel. The focus of this study is on the collection and use of non-rainfall water and its impact on the environment’s ecology. The water cycle and the carbon biogeochemical cycle in arid and semi-arid regions are affected by the interaction between non-rainfall water and biological crust. Recently, the study on the interaction between non-rainfall water and biological crusts has grown radically. Understanding the origins and evolution of coastal fog is crucial to enhance the precision of coastal fog forecasts by considering all relevant meteorological, climatic, and boundary layer factors. The modeling of soil moisture adsorption remains a significant obstacle, nevertheless. Precipitation is less concentrated in heavy isotopes than dew or fog water. The stable isotope technique is a useful tool for researching the ecohydrological impacts of dew and fog water due to the variation in isotope composition. More research has been done on dew than on fog water or soil moisture adsorption. However, extensive regional research is limited, including long-term studies on non-rainfall water or studies on natural surface condensation. Current studies on non-rainfall water are unable to provide a comprehensive grasp of its spatiotemporal variance. Future research must discover and develop new technologies and new methods to collect, observe, and model non-rainfall water on natural surfaces, investigate the large spatial scale and long-term non-rainfall water observation and simulation, and reveal influences of non-rainfall water on the water cycle, eco-hydrology, and climatic change to deepen the understanding of non-rainfall water as a nontraditional water resource.

Key words: non-rainfall water, dew, fog, water vapor adsorption