THE UTILIZATION OF MELALEUCA CAJUPUTI IN DEGRADED PEAT SWAMP

在泰国，天然泥炭沼泽森林只有在那拉提瓦才能找到。但是，最近，这些沼泽林的大片面积迅速开垦用于农业。原始形式的热带低地泥炭沼泽是一个紧密而脆弱的生态系统，黄铁矿沉积物或海沙位于泥炭层的底部，泥炭层充满了酸性、缺氧和营养不良的水。为发展退耕还林退化土地恢复技术，在沙质土区、粘质沙质土区、周期性淹水区、泥炭沼泽区等不同立地条件下进行了千里香种植试验。在积水中生长的千层草有根和根际氧化，而在鼓泡水中生长的千里光几乎没有根和根际的氧化。通过测定腺苷类物质含量及糖酵解和…活性，研究了淹水白千层根系的能量代谢。淹水条件下的发酵酶较多。在淹水幼苗上观察到根系的径向氧损失，这表明淹水后的千层草可能发育了通气组织，这可能使其能够在长期的淹水条件下存活。退化泥炭区是野火多发地区。以退化泥炭和酸性硫酸盐土区为研究对象，研究了严重野火后植被的早期恢复过程。连续测定了白千层茎粗的日变化，作为植物水分状况的一个指标。根据累积太阳辐射与茎粗累积干缩的关系，提出了一种新的水分胁迫指数，该指数可能是水分胁迫条件下植物生长减慢的一个指标。这些结果可能对改善退化热带低地泥炭地的恢复有一定的参考价值。白千层作为先锋树种的典型特征可能是使该物种对人类有用的重要因素。较少

In Thailand, natural peat swamp forests can be found only in Narathiwat. But, recently, the wide area of these swamp forests reclaimed rapidly for agriculture. The tropical lowland peat swamp in its original form is a tight and fragile ecosystem in which pyrite sediment or marine sand lies at the base and acid, oxygen-deficient and nutrient-poor water fills the peat layer. To develop restoration techniques for degraded land through reforestration, Melaleuca cajuputi planting trial has been carried out under different site conditions, such as sandy soil area, clay-sandy soil area, periodically-flooding area and peat swamp area. The oxidation of roots and rhizosphere was found in Melaleuca cajuputi grown in stagnant water, while almost no oxidation of roots and rhizosphere was found in Melaleuca cajuputi grown in air-bubbling water. The energy metabolism in roots of flooding Melaleuca cajuputi, has been investigated by measuring adenylates concentrations and activities of glycolytic and … More fermentative enzymes under flooding conditions. Radial oxygen loss from roots was observed on the flooded seedlings, suggesting that aerenchyma might be developed in flooded Melaleuca cajuputi, possibly enabling to survive under prolonged flooded conditions. The degraded peat area was happened wildfire frequently. The early recovery process of vegetation after a severe wildfire was investigated in degraded peat and acid sulfate soil area. Diurnal change in stem diameter of Melaleuca cajuputi was continuously measured as an index of plant water status. New water-stress index was developed from the relationship between cumulative solar radiation and cumulative shrinkage of stem diameter, which is a possible index of plant growth reduction under water-stress conditions. These results may be useful for the improvement of rehabilitation of degraded tropical lowland peat lands. The typical characteristics of Melaleuca cajuputi as a pioneer tree may be important factors that make this species is useful to human. Less