This study was conducted to analyze the effectiveness of using reflective mulch under the stands of oil palm plants of several ages on the intensity of solar radiation reflection, growth, chlorophyll content, and photosynthetic characteristics of soybeans. A nested design was used, with the first factor of oil palm age group consisting of open land and land under oil palm stands aged 4, 5, and 8 years. The second factor was the reflective mulch that included land without mulch, land with inorganic reflective mulch, and land with organic reflective mulch. The use of reflective mulch in the soybean-oil palm intercropping system was able to increase the reflection intensity of surface solar radiation, as well as increase the soybean solar radiation interception. The use of inorganic and organic reflective mulch significantly increased the leaf area, specific leaf weight, and soybean stomatal density. Organic reflective mulch led to significant reductions in the amount of chlorophyll A and B content. The photosynthetic rate of soybean in lower leaves was increased significantly. Inorganic reflective mulch resulted in significant reductions in the rate of transpiration, intercellular CO₂ concentration, and conductance of soybean stomata in lower leaves. The use of reflective mulch contributed to improved soybean performance under oil palm stands. The use of organic reflective mulch for soybean grown under oil palm stands aged up to 5 years resulted in better growth rates due to the increased intensity of solar radiation reflected from the surface. However, the reflection effect could not meet the needs of soybean solar radiation on land under oil palm stands aged >5 years due to the very low transmission. Therefore, the use of organic reflective mulch is more effective and efficient in the soybean-oil palm intercropping system until the oil palm reaches the age of 5 years.

中文翻译：

---

大豆和油棕间作系统中反射性覆盖的有效性：对生长，叶绿素含量和光合特性的影响

进行了这项研究，以分析在数个年龄的油棕植物林下使用反射性覆盖物对大豆的太阳辐射反射强度，生长，叶绿素含量和光合特性的有效性。使用的是嵌套设计，油棕年龄组的第一个因素包括开阔土地和4、5和8岁的油棕林下的土地。第二个因素是反射覆盖物，其中包括无覆盖土地，具有无机反射覆盖物的土地和具有有机反射覆盖物的土地。在大豆-油棕间作系统中使用反射性覆盖物能够增加表面太阳辐射的反射强度，并增加大豆太阳辐射的拦截能力。无机和有机反射覆盖物的使用显着增加了叶片面积，比叶重和大豆气孔密度。有机反射覆盖物导致叶绿素A和B含量的显着减少。下部叶片中大豆的光合速率显着提高。无机反射覆盖物导致蒸腾速率，细胞间CO显着降低₂浓度和下部叶片中大豆气孔的电导率。使用反射性覆盖料有助于改善油棕林下的大豆性能。由于从表面反射的太阳辐射强度增加，使用有机反光覆盖物在油棕林下（长达5年）种植的大豆可提高生长速度。然而，由于透射率非常低，反射效果不能满足大豆油在大于5年的油棕林下土地上的太阳辐射需求。因此，在大豆-油棕间作系统中使用有机反光覆盖物更为有效，直到油棕达到5岁为止。