Several experimental tools allow researchers to manipulate environmental variables to simulate future climate change scenarios during in situ seed ecology studies. The most common ones are designed to modify a single environmental variable. For example, open-top chambers (OTCs) increase temperature or rain-out shelters decrease precipitation. However, changes in environmental variables in the future are expected to happen simultaneously, and at present, an understanding of their combined effects in natural environments is limited. Here, we present a passive novel OTC design that simultaneously increases the soil temperature and decreases soil moisture. We assessed the performance of the design during 1 year in a high-mountain environment and reported its effects on the organic and topsoil layers. The modified OTC reduced the soil volumetric water content throughout the study period. Overall, chambers increased the mean day air temperature by 3.3 °C (at 10 cm above the soil surface), the mean day soil surface temperature by 1.35 °C and the mean day below the soil surface temperature by 1.30 °C (at −5 cm) and 1.25 °C (at −10 cm). Remarkably, surface and soil temperatures remained warmer at night (+0.65 at soil surface, +0.41 at −5 cm and +0.24 at −10 cm). We detail the design plans, tools and materials needed for its construction. Furthermore, we recommend on how to use it during seed ecology studies. This tool can help increase our understanding of the potential responses of seeds and seedlings to the combined effects of warming temperatures and a decrease in precipitation.

中文翻译：

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干燥和温暖：用于种子生态学研究的改良开顶室


一些实验工具允许研究人员在原位种子生态学研究期间操纵环境变量以模拟未来的气候变化情景。最常见的是修改单个环境变量。例如，开顶室 （OTC） 会增加温度，或者防雨棚会减少降水。然而，预计未来环境变量的变化将同时发生，目前，对它们在自然环境中的综合影响的理解是有限的。在这里，我们提出了一种被动的新型 OTC 设计，它可以同时提高土壤温度并降低土壤水分。我们在高山环境中评估了 1 年的设计性能，并报告了其对有机质和表土层的影响。改性 OTC 在整个研究期间降低了土壤体积含水量。总体而言，暗室使平均日空气温度提高了 3.3 °C（在土壤表面以上 10 厘米处），平均日土壤表面温度提高了 1.35 °C，平均日温度比土壤表面温度低增加了 1.30 °C（在 -5 厘米处）和 1.25 °C（在-10 厘米处）。值得注意的是，地表和土壤温度在夜间仍然较高（土壤表面为 +0.65，-5 厘米处为 +0.41，-10 厘米处为 +0.24）。我们详细说明了建造它所需的设计计划、工具和材料。此外，我们还推荐了如何在种子生态学研究中使用它。该工具可以帮助我们加深对种子和幼苗对温度升高和降水减少的综合影响的潜在反应的理解。