[1]YANG Yikun.Water Consumption Regularity and Its Environmental Influencing Factors in Different Forests of Jinyun Mountain in Chongqing City[J].Research of Soil and Water Conservation,2020,27(01):126-131,138.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
27
Number of periods:
2020 01
Page number:
126-131,138
Column:
Public date:
2020-02-20
- Title:
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Water Consumption Regularity and Its Environmental Influencing Factors in Different Forests of Jinyun Mountain in Chongqing City
- Author(s):
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YANG Yikun
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(Chongqing Three Gorges Vocational College, Chongqing 400020, China)
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- Keywords:
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Jinyun Mountain; forest; transpiration; water use efficiency
- CLC:
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S715.4
- DOI:
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- Abstract:
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Taking Jinyun Mountain of Chongqing as the experimental site, we measured the dynamic characteristics of water consumption in three typical stands of mixed coniferous and broad-leaved forest, evergreen broad-leaved forest and bamboo forest by using LI-6400 XT portable photosynthetic assay system from January to December, 2018, and quantitatively analyzed the relationship between transpiration and evaporative water use efficiency and environmental factors. The results showed that soil evaporation in different stands of Jinyun Mountain presented the pattern of several changes, reaching the maximum in July-August and increasing sharply in April-June, after September, soil evaporation in different stands decreased, and soil evaporation in the same month decreased in the order: broad-leaved forest>mixed forest>needle moso bamboo forest; the transpiration rates of different stands in Jinyun Mountain presented a single-peak curve, which increased slowly from January to June, reached the maximum in July to August, and decreased sharply after August, based on the stationary trend in November to December, the transpiration rates in the same month basically decreased in the order: broad-leaved forest>mixed forest>needle moso bamboo forest; different forest transpiration rates showed unimodal type curve change rule since 6:00 am, leaf transpiration rate increased with different within a day of photosynthetic active radiation intensity, stomatal opening, and sharply peaked at 8:00, and then transpiration rate declined slowly, the same time transpiration rate decreased in the order: evergreen broad-leaved forest>mixed forest>needle moso bamboo forest; the variation trend of water use efficiency and transpiration rate in different stands of Jinyun Mountain was consistent. Partial correlation analysis shows that different physiological and ecological factors of forest stand water use efficiency(WUE)correlation coefficient is higher than the transpiration rate and the correlation coefficient of the physiological and ecological factors, the transpiration rate and water use efficiency and stomatal conductance(Gs), intensity of photosynthetic active radiation(PAR)are significant or extremely significant positive correlation, and transpiration rate and water use efficiency have no significant correlation with air relative humidity(RH)(p>0.05), Gs and PAR of different forest stand have the largest contribution to the transpiration rate and water use efficiency. Regression analysis shows that there is a linear relationship between transpiration rate and WUE of different stands and physiological and ecological factors, and the dominant factors affecting transpiration rate and WUE of different stands include Gs and PAR.