Eucalyptus tree stocking can be adjusted to increase, depending on purpose, cellulose, timber or bioenergy production, but the effect of stocking on ecosystem water balance is still understudied. Studies on soil and catchment hydrology and forest management, encompassing distinct climatic years, are needed for understudied ecosystems to improve water use efficiency and streamflow regulation, and thus bridging forestry and ecosystem processes. For different Eucalyptus dunnii stockings, we measured rainfall dynamics to quantify rainfall partitioning, soil water balance, and eucalyptus water use efficiency in a sandy soil. Total rainfall, throughfall, stemflow, canopy interception, evapotranspiration, tree growth, and water use efficiency were evaluated over a 1-year study period (5th to 6th years after planting), in low (LS: 816 trees ha⁻¹), medium (M: 1,633 trees ha⁻¹), medium–high (MH: 3,265 trees ha⁻¹), and high tree stockings (HS: 6,568 trees ha⁻¹). Tree stocking had no clear relation with the partitioning of annual rainfall (P, 2583 mm) into canopy interception (34–37% of P) and effective rainfall (63–66% of P). By increasing tree stocking from 816 to 6,568 trees ha⁻¹, throughfall decreased from 62 to 53% of P, and stemflow increased from 2.1 to 12.7% of P. Estimated deep drainage was <0.16% of P, even though the annual rainfall was almost double of historical rainfall and surface runoff was only 5.7% of P. Thus, groundwater recharge in Eucalyptus plantation may be potentially low even with high rainfall in a soil with high infiltration and low slope (about 4%). Cumulative evapotranspiration varied between 1304 and 1438 mm (50–56% of P), highest for high tree stocking, whereas daily evapotranspiration rates varied between 0.8- and 11.7-mm d⁻¹. From the 5th to the 6th year after planting, the individual wood production varied from 4.9 (HS) to 51.8 kg⁻¹ tree (LS), and stand wood production varied from 27.1 (MHS) to 42.2 (LS) Mg ha⁻¹ yr⁻¹. Water use efficiency varied from 2.1 to 3.1 g L⁻¹, respectively for MHS and LS. Industrial eucalyptus planted in sandy soils at high stocking for energy production may overuse stored water, affecting long-term forest sustainability. Therefore, the challenge is decreasing evaporation from soil and canopy and increasing green-water use efficiency, while generating surface runoff for ecological flows and groundwater recharge (blue water flow).

桉树的放养可以根据用途、纤维素、木材或生物能源的生产进行调整，以增加放养，但放养对生态系统水平衡的影响仍有待研究。研究不足的生态系统需要对土壤和集水区水文和森林管理进行研究，包括不同的气候年份，以提高用水效率和流量调节，从而连接林业和生态系统过程。对于不同的桉树 dunnii长袜，我们测量了降雨动态，以量化沙质土壤中的降雨分配、土壤水分平衡和桉树水分利用效率。在 1 年的研究期内（种植后第 5 至第 6 年）评估了总降雨量、穿透量、茎流、树冠截留、蒸散量、树木生长和水分利用效率，低（LS：816 棵树 ha ^-1），中（M：1,633 棵树 ha ^-1）、中高（MH：3,265 棵树 ha ^-1）和高树长袜（HS：6,568 棵树 ha ^-1）。树木放养与将年降雨量（P，2583 毫米）划分为冠层截留量（P 的 34-37%）和有效降雨量（P 的 63-66%）之间没有明显关系。通过将树木蓄积从 816 棵树增加到 6,568 棵树 ha ^-1, 流量从 P 的 62% 减少到 53%，茎流从 P 的 2.1% 增加到 12.7%。估计深部排水量小于 P 的 0.16%，尽管年降雨量几乎是历史降雨量的两倍，地表径​​流仅为 5.7%因此，即使在高渗透和低坡度（约 4%）的土壤中降雨量大，桉树人工林的地下水补给量也可能很低。累积蒸散量在 1304 和 1438 毫米（P 的 50-56%）之间变化，高树放养最高，而每日蒸散量在 0.8- 和 11.7-mm d ^-1之间变化。从种植后的第 5 年到第 6 年，个体木材产量从 4.9 (HS) 到 51.8 kg ^-1树 (LS)不等，而立材产量从 27.1 (MHS) 到 42.2 (LS) Mg ha ^{-1 不等}年^-1。MHS 和 LS 的用水效率分别从 2.1 到 3.1 g L ^-1不等。在沙质土壤中种植用于能源生产的高放养的工业桉树可能会过度使用储存的水，影响森林的长期可持续性。因此，面临的挑战是减少土壤和树冠的蒸发，提高绿水利用效率，同时为生态流和地下水补给（蓝水流）产生地表径流。