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- Li, Cheng, et al.
(författare)
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Introducing water factors improves simulations of maize stomatal conductance models under plastic film mulching in arid and semi-arid irrigation areas
- 2023
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Ingår i: Journal of Hydrology. - : Elsevier BV. - 0022-1694. ; 617
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Tidskriftsartikel (refereegranskat)abstract
- Plastic film mulching (PFM) in the cropland may alter biophysical conditions for crop growth, which may not be accounted for in existing stomatal conductance models. This can affect the accuracy of carbon–nitrogen-water cycle simulations for the soil-crop systems and hamper our understanding of internal mechanisms that control plant leaf stomatal conductance (gsw). To evaluate the simulations of PFM effects on gsw, the three models (i.e., Ball-Woodrow-Berry (BWB), Ball-Berry-Leuning (BBL), and unified stomatal optimization (USO) models) were used. The two model modification factors were leaf-air temperature difference (ΔT) and a water response function (f(θ)). A two-year maize (Zea mays L.) field experiment was conducted under different PFM (black, transparent, and no-mulch). The performance of the BWB model was poor under varying water status in the arid irrigation area. As for the BBL and USO models, the coefficient of determination and modified efficiency coefficient of the modified models increased 5.8%–90.6% and 6.5%–145.4%, respectively, compared with the initial models. The root mean square error and relative error of the modified models decreased 3.5%–67.9% and 4.8%–65.6%, respectively. The ΔT and f(θ) factors effectively improved the BBL and USO models, but the f(θ)-modified models performed better than ΔT-modified models under PFM. Overall, our results suggest that the maize land implemented with plastic film mulching has altered biophysical conditions, leading to significant changes in crop photosynthesis, leaf-air temperature difference and top-soil water conditions. Accurate estimates of stomatal conductance require the model to consider water response functions and leaf-air temperature difference, particularly in environmental conditions associated with different extents of water deficit or drought.
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| 2. |
- Li, Cheng, et al.
(författare)
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Ridge planting with transparent plastic mulching improves maize productivity by regulating the distribution and utilization of soil water, heat, and canopy radiation in arid irrigation area
- 2023
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Ingår i: Agricultural Water Management. - : Elsevier BV. - 0378-3774. ; 280
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Tidskriftsartikel (refereegranskat)abstract
- Ridge-furrow mulching system is widely used for improving soil hydrothermal conditions and crop productivity in semiarid and arid rainfed areas. The response of crop productivity to resource capture and utilization is crucial for agricultural field management and sustainable development. However, few have simultaneously investigated the coupling effect of plastic film mulching (PM) types and planting patterns on root and shoot growth, photosynthesis, yield, resource capture and utilization as well as their potential links in the same experiment, especially in arid irrigation areas, limiting our understanding of PM and ridge planting application. This study conducted a two-year field experiment with four treatments: 1) flat planting with transparent plastic film mulch (FT); 2) flat planting with black plastic film mulch (FB); 3) ridge–furrow planting with transparent plastic film mulch (RT); 4) ridge–furrow planting with black plastic film mulch (RB). The results showed that RT significantly increased soil water storage and root growth at the silking and grain-filling stages in both years by enhancing soil thermal time with 151.9–176.2 °C d and the intercepted photosynthetic active radiation with 22.2–57.4 MJ m–2. In addition, RT had a significantly higher net photosynthetic rate than FT and FB at the 12-leaf and silking stages, enhancing the transportation of stem and leaf to grain. The logistic equation using growing degree days as the independent variable characterized the dynamic features of maize growth under different PM types (transparent or black) coupled with ridge–furrow planting. RT accelerated dry matter accumulation by enhancing the maximum growth rate and extending the rapid growth period, resulting in 12.9–15.2 % more dry matter accumulation and 10.0–16.7 % higher grain yields than FB. Furthermore, RT significantly increased resource use efficiencies by 10.1–17.3 % for water, 3.0–5.5 % for thermal, and 4.0–9.1 % for radiation compared with FB. Ridge planting had the highest contributor rates, with >40 % for yield and resource capture. This study suggests that RT maintains high maize productivity and resource use efficiencies in arid irrigation areas with limited water resources by regulating soil water, heat, and canopy radiation distribution and utilization.
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