The experiment was carried out in a research field near Murcia, Spain, over a 3-week period between September 26 and October 16, 2000. Sixteen trees were used in the experiment, eight of which were placed under a rectangular shading net, while the other eight were maintained in the open air. Trees were irrigated once per day and, after October 5th, water was witheld from eight trees (four shaded and four unprotected for 5 days). The leaf stomatal conductance and the photosynthesis rates were higher in the shaded trees than in the exposed plants, probably because the leaf water potential was lower in the unshaded plants. This higher leaf conductance partially compensated for the effect of low radiation on transpiration, and the reduction of daily sap flow registered in shaded trees was only around 10-20%. The net also affected trunk diameter changes, with the shaded trees showing lower values of maximum daily shrinkage. Soil water deficit and high radiation had a similar effect on plant water parameters, lowering leaf water potential, leaf stomatal conductance, and the photosynthesis rate. The effects of both conditions were accumulative and so the exposed water-stressed plants showed the lowest values of total hydraulic resistance and water use efficiency, while the shaded well-irrigated trees registered the highest values for both parameters. For this reason, we think that net shading could be extended to apricot culture in many areas in which irrigation water is scarce and insolation is high.

中文翻译：

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在遮阳网和不同供水条件下生长的杏树幼树的液流、气体交换和水力传导

该实验于 2000 年 9 月 26 日至 10 月 16 日在西班牙穆尔西亚附近的一个研究领域进行，为期 3 周。实验中使用了 16 棵树，其中 8 棵树被放置在矩形遮阳网下，而其他八人保持在露天。树木每天灌溉一次，10 月 5 日之后，八棵树（四棵遮荫，四棵未受保护的 5 天）停止浇水。遮荫树的叶气孔导度和光合作用速率高于暴露植物，这可能是因为未遮荫植物的叶水势较低。这种较高的叶片电导部分补偿了低辐射对蒸腾作用的影响，并且在遮荫树木中记录的每日树液流量减少仅约 10-20%。网也影响了树干直径的变化，阴影树木的最大日收缩值较低。土壤水分亏缺和高辐射对植物水分参数有相似的影响，降低了叶片水势、叶片气孔导度和光合作用速率。两种条件的影响都是累积性的，因此暴露在水分胁迫下的植物的总水力阻力和水分利用效率的值最低，而遮荫的灌溉良好的树木在这两个参数上的值都最高。出于这个原因，我们认为在许多灌溉用水稀缺且日照率高的地区，可以将网遮蔽推广到杏树栽培中。土壤水分亏缺和高辐射对植物水分参数有相似的影响，降低了叶片水势、叶片气孔导度和光合作用速率。两种条件的影响都是累积性的，因此暴露在水分胁迫下的植物的总水力阻力和水分利用效率的值最低，而遮荫的灌溉良好的树木在这两个参数上的值都最高。出于这个原因，我们认为在许多灌溉用水稀缺且日照率高的地区，可以将网遮蔽推广到杏树栽培中。土壤水分亏缺和高辐射对植物水分参数有相似的影响，降低了叶片水势、叶片气孔导度和光合作用速率。两种条件的影响都是累积性的，因此暴露在水分胁迫下的植物的总水力阻力和水分利用效率的值最低，而遮荫的灌溉良好的树木在这两个参数上的值都最高。出于这个原因，我们认为在许多灌溉用水稀缺且日照率高的地区，可以将网遮蔽推广到杏树栽培中。而有阴影的灌溉良好的树木在这两个参数上都记录了最高值。出于这个原因，我们认为在许多灌溉用水稀缺且日照率高的地区，可以将网遮蔽推广到杏树栽培中。而有阴影的灌溉良好的树木在这两个参数上都记录了最高值。出于这个原因，我们认为在许多灌溉用水稀缺且日照率高的地区，可以将网遮蔽推广到杏树栽培中。