以原生植群移除嘉義布袋廢曬鹽場土壤鹽分之可行性探討

Study on Removed Soil Salts from Abandoned Brine in Budye, Chayi by Native Vegetations

本試驗自2001年3月起，於嘉義布袋之廢棄鹽場設置3個樣區，試圖探討植物覆蓋度與土壤氯離子（Cl-）含量之關係，藉以瞭解生長於高鹽分含量鹽場之植物的生長與分佈情形，並利用這些植物吸收、累積Cl-之特性，設法改善鹽場之生育環境。根據調查資料顯示，所選定之3個樣區於7-10月降雨後常積水，植群多聚集於樣區四周的田埂上，樣區中幾無植物覆蓋；10月至翌年2月乾旱時樣區積水消退，則漸有植物朝向樣區內匍匐生長。土壤及植物體內Cl-含量於降雨時下降，乾旱時逐漸升高，而植物體內之Cl-含量較土壤為高，顯示植物覆蓋於鹽場將累積土壤之鹽分於體內。各種植物體內累積鹽分的情形亦有不同，鹽地鼠尾粟（Sporobolus virginicus）傾向將鹽分累積於地下部，而鹽定（Suaeda nudiflora）與濱水菜（Sesuvium portulacastrum）則累積於地上部。經實際移除樣區內小區塊之所有植物，共移出500-1000gCl-，相當於約30kgha-1之Cl-移除率。藉植物吸收Cl-之特性將樣區內植物移除於樣區外，可將植物體內累積之Cl-自樣區中移除，淡化土壤Cl-含量，達成復育之目地應為可行。然必須克服廢棄鹽場因漲潮或大雨所造成的長時間淹水問題，否則將導致當地植物無法成活。 Three plots on abandoned brine pan in Budye, Chayi, have been set on March 2001. Therelationship between plant coverage and chloride content was studied to know the growth states anddistribution of plant growing in high salinity pan. In order to understand how the plant to decrease salinity of salt pond, some characteristics of plant grown in it were used, such as accumulation and storage of salt.According to the investigated information, three plots often flooded after raining from July to October.During this period, there was no vegetation in central area of plot. From October to February in the nextyear, plots were dried and plant coverage was increased. Both soil and plant chloride contents were lowerafter raining, and gradually higher when plots getting drier. The chloride content of plant is higher thanthat of soil for few times. It is indicated that the plants can accumulate the salts from soil and decreasesoil salt concentration. The chloride accumulations in different parts of plant were difference from speciesto species, Sporobolus virginicus tented to accumulate in roots, and Suaeda nudiflora and Sesuviumportulacastrum tented to accumulate in shoots. 500-1000 g chlorides were moved out after all vegetationswere removed from three blocks in one plot (about 30 kg ha-1). By this way, it is possible that theabandoned brine pan will be rehabilitated. However, it must to avoid that long term flooding inabandoned brine pans caused by high tide or heavily raining, otherwise the plants grown originally couldnot survive.

Three plots on abandoned brine pan in Budye, Chayi, have been set on March 2001. Therelationship between plant coverage and chloride content was studied to know the growth states anddistribution of plant growing in high salinity pan. In order to understand how the plant to decrease salinity of salt pond, some characteristics of plant grown in it were used, such as accumulation and storage of salt.According to the investigated information, three plots often flooded after raining from July to October.During this period, there was no vegetation in central area of plot. From October to February in the nextyear, plots were dried and plant coverage was increased. Both soil and plant chloride contents were lowerafter raining, and gradually higher when plots getting drier. The chloride content of plant is higher thanthat of soil for few times. It is indicated that the plants can accumulate the salts from soil and decreasesoil salt concentration. The chloride accumulations in different parts of plant were difference from speciesto species, Sporobolus virginicus tented to accumulate in roots, and Suaeda nudiflora and Sesuviumportulacastrum tented to accumulate in shoots. 500-1000 g chlorides were moved out after all vegetationswere removed from three blocks in one plot (about 30 kg ha-1). By this way, it is possible that theabandoned brine pan will be rehabilitated. However, it must to avoid that long term flooding inabandoned brine pans caused by high tide or heavily raining, otherwise the plants grown originally couldnot survive.