In agroforestry systems, such as integrated crop-livestock-forest (iCLF), the agricultural, livestock and arboreal components are explored in the same field in rotation, succession or intercropping. Our objective was to investigate if the diameter growth of eucalyptus in agroforestry systems differs from those cultivated as a planted forest, as well as to assess whether there is a difference in its growth in face of the air temperature and precipitation. The study was held at Ponta Porã, Brazil, a region of humid subtropical climate with hot summers and soil classified as Oxisol, which is fertile, deep and clayey. Dendrometer bands measured the diameter growth of eucalyptus (Eucalyptus urograndis) cultivated as a forest and in iCLF, with eucalyptus rows distance of 12.5 × 12.5 m, 12.5 m one side × 25 m another side and 25 × 25 m. The study took place from four years and nine months after transplanting till six years and seven months (22 months monitoring). On iCLF, the inter-row was explored with grain crops (soybean or corn) and pasture. Climate data of air temperature and precipitation were used to investigate their influence or not on diameter growth. Eucalyptus diameter growth is higher when cultivated in agroforestry systems and this growth is as higher as larger is the distance between eucalyptus rows. Precipitation proved to strongly and positively influence the diameter growth, especially when cultivated in agroforestry systems. On the other hand, under the conditions of this study, air temperature showed little or no correlation with eucalyptus diameter growth.

Graphical abstract

中文翻译：

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农林复合系统中桉树的直径生长及其与气温和降水的关系

在农林业系统中，例如农作物-牲畜-森林综合体（iCLF），农业、牲畜和树木组成部分在同一田地中以轮作、连续或间作的方式进行开发。我们的目的是调查农林复合系统中桉树的直径生长是否与人工林栽培的桉树直径生长不同，并评估其生长在气温和降水方面是否存在差异。这项研究是在巴西蓬塔波拉进行的，​​该地区属于潮湿的亚热带气候，夏季炎热，土壤属于 Oxisol，肥沃、深厚且粘质。树木仪带测量了人工林和 iCLF 中栽培的桉树 ( Eucalyptus urograndis )的直径生长，桉树行距为 12.5 × 12.5 m、一侧 12.5 m × 25 m 另一侧和 25 × 25 m。该研究从移植后四年零九个月一直持续到六年零七个月（22个月监测）。在 iCLF 上，对谷类作物（大豆或玉米）和牧草进行了行间探索。利用气温和降水的气候数据来研究它们对直径增长的影响。当在农林复合系统中种植时，桉树的直径增长得更高，并且桉树行之间的距离越大，这种增长就越高。事实证明，降水对直径的增长有强烈而积极的影响，特别是在农林复合系统中种植时。另一方面，在本研究的条件下，气温与桉树直径增长几乎没有相关性或没有相关性。

图形概要