不同咸水利用方式对棉花叶绿素荧光参数及土壤盐分的影响

【目的】本研究旨在科学合理地利用浅层咸水资源。【方法】依托短期定位试验开展了在第3年和第4年不同咸水利用方式下(CK:造墒和蕾期灌淡水;T1:造墒和蕾期灌咸淡混配矿化度3 g·L^-1的微咸水;T2:淡水造墒蕾期灌矿化度5 g·L^-1咸水;T3:造墒和蕾期灌矿化度5 g·L^-1咸水;T4:淡水造墒蕾期不灌水)棉花长势、叶绿素荧光参数、土壤盐分累积及其运移的变化。【结果】T1和T2处理的齐苗率、株高、干物质质量、叶面积指数、叶绿素荧光参数、产量及霜前花率与CK无显著差异,土壤盐分含量较CK有所增加,但未对棉花生长产生明显抑制。T3处理的棉花长势指标、叶绿素荧光参数较CK显著降低,0~100 cm土壤盐分含量较CK明显增加。【结论】从土壤质量安全和咸水高效利用的角度考虑,连续4年用3 g·L^-1的咸淡混合水灌溉或用淡水与5 g·L^-1的咸水轮灌不仅能节约淡水,且不影响棉花产量。本研究结果为当地在棉花生产中安全利用咸水提供技术参考。

Effects of different saline water irragation on chlorophyll fluorescence parameters in cotton and the soil salt content

[Objective] There is a shortage of fresh water and abundant shallow saline water in Hebei Low Plain. This research aims to make scientifical and reasonable use of saline water resources. [Method] The field experiment with five treatments (CK, freshwater irrigation; T1, blended irrigation by mixing fresh water and saline water into 3 g·L^－1 saline water; T2, rotated irrigation of 5 g·L－1 saline water with fresh water; T3, direct irrigation with 5 g·L^－1 saline water; T4, irrigation before sowing no irrigation in bud stage) was conducted to study cotton growth, chlorophyll fluorescence parameters, communication and transportation of soil salinity based on short-term saline water irrigation experiment at the 3^rd and 4^th year. [Result] The results showed that the T1 and T2 treatments had no significant differences in seedling emergence, plant height, dry matter weight, leaf area index, chlorophyll fluorescence parameters, yield, and pre-frost cotton rate compared with CK. While, there was an increasing tendency in soil salt content, the plant growth was not impacted, either. In comparison with CK, growth indicators and chlorophyll fluorescence parameters of the treatment T3 decreased significantly, but salt content in 0-100 cm depth of soil layers increased evidently. To sum up, the treatments T1 and T2 did not show obvious negative impacts on cotton growth. [Conclusion] From the perspective of soil quality and efficient use of saline water, the blended irrigation pattern (mixing fresh water and saline water into 3 g·L^－1 saline water) and the rotated irrigation pattern (fresh water and 5 g·L^－1 saline water) of saline water utilization can save freshwater, but do not decrease cotton yield. The study provided an important technical reference for use of saline water irrigation of cotton.