Ibrahim Mohamad Hilmi, Jaafar Salwana, Yamashita Naoyuki, Sase Hiroyuki
Agrotechnology Programme, Faculty of Resources Science and Technology Universiti Malaysia Sarawak Kota Samarahan Sarawak Malaysia.
Institute for Biodiversity and Environmental Research, Universiti Brunei Darussalam Gadong Brunei Darussalam.
Plant Environ Interact. 2024 Aug 20;5(4):e70005. doi: 10.1002/pei3.70005. eCollection 2024 Aug.
This study examines the critical interaction between seasonal precipitation variability and forest maturity in determining ion deposition patterns in rehabilitated forest ecosystems. This research was conducted in rehabilitated forest sites in Bintulu, Sarawak, Malaysia that had ecologically similar plant distribution, species, and age in each planting area. This facilitated the standardization of rainfall deposition in the different study plots which streamlined the study of these specific facets of ecosystem dynamics. The goal is to understand how seasonal changes and the age of the forest influence the chemical composition of the flux that relates to the movement and deposition of nutrients through the forest ecosystem. This flux is a key factor in the health of the forest ecosystem and nutrient cycling. Using ion exchange resin (IER) samplers, we accurately measured and compared the deposition of different ions (Ca, Na, Fe, Cu, NO , NH and SO ) across different seasons and forest ages. The deposition of Ca and NH₄ was significantly lower in the low-precipitation season than in the high-precipitation season in all forest stands, regardless of the year they were established (1996, 1999, 2002, 2005, and 2009). In contrast, ions such as Na, Fe, Cu, NO and SO showed no clear seasonal fluctuations. In addition, the study shows that through-fall in forest stands from 2002, 2005 and 2009 had higher concentrations of Ca in both seasons than in 1996 and 1999. Interestingly, forest stands from 2009 and 2002 had elevated levels of Na and SO₄ in seasons with low precipitation, while stands from 1996 had higher levels in seasons with high precipitation. Our results emphasize the crucial role of precipitation amount and canopy age in determining ion deposition in forest ecosystems. By demonstrating the significant influence of precipitation seasonality and forest maturity on the chemical composition of throughfall, this study contributes to a deeper understanding of nutrient dynamics in developing forest landscapes and provides valuable insights for ecological restoration measures.
本研究考察了季节性降水变率与森林成熟度之间的关键相互作用，以确定恢复森林生态系统中的离子沉积模式。本研究在马来西亚砂拉越民都鲁的恢复森林地点开展，每个种植区域的植物分布、物种和年龄在生态上相似。这便于不同研究地块降雨沉积的标准化，从而简化了对生态系统动态这些特定方面的研究。目标是了解季节变化和森林年龄如何影响与养分在森林生态系统中的移动和沉积相关的通量的化学成分。这种通量是森林生态系统健康和养分循环的关键因素。我们使用离子交换树脂（IER）采样器，准确测量并比较了不同季节和不同林龄森林中不同离子（钙、钠、铁、铜、硝酸根、铵根和硫酸根）的沉积情况。在所有林分中，无论其建立年份（1996年、1999年、2002年、2005年和2009年）如何，钙和铵根的沉积在低降水季节均显著低于高降水季节。相比之下，钠、铁、铜、硝酸根和硫酸根等离子没有明显的季节性波动。此外，研究表明，2002年、2005年和2009年林分的穿透雨中钙的浓度在两个季节均高于1996年和1999年。有趣的是，2009年和2002年的林分在低降水季节钠和硫酸根水平升高，而1996年的林分在高降水季节水平更高。我们的结果强调了降水量和树冠年龄在决定森林生态系统中离子沉积方面的关键作用。通过证明降水季节性和森林成熟度对穿透雨化学成分的显著影响，本研究有助于更深入地理解发育中的森林景观中的养分动态，并为生态恢复措施提供有价值的见解。
