坡地土壤植被復育之探討

由於臺灣地形地勢狹長，山高水急，故造就臺灣不少坡地地形，近年來因氣候之變遷，溫室效應急劇，使得全球極端氣候越趨明顯；加上颱風帶來之豪大雨，對臺灣的災害亦是一年比一年嚴重，尤其是山坡地地形，經雨水沖刷，坡地露出於地表，進而引發嚴重之土石流災害，造成植被退化、山坡地裸露，災後環境復原困難，使得人身安全及經濟產業皆受到了重大之威脅。本研究使用黑麥草，做為植被復育之草種，搭配高分子聚合物：聚乙烯醇(Polyvinyl alcohol，PVA)、聚丙烯酸(Poly（acrylic acid），PAA)，及聚麩胺酸(gamma-Polyglutamic acid，γ-PGA)，研究高分子聚合物濃度比例之調配，再施用於土壤上，使植物能快速生長又能促使土壤團粒化，於短期內使坡地土壤之環境有所改善。本試驗為在土壤中添加不同濃度之高分子聚合物，探討不同濃度之高分子聚合物對土壤團粒化和植物之影響。結果顯示，高分子聚合物的濃度越高發芽率則越低，黑麥草發芽率方面，在添加聚乙烯醇濃度0.5%、0.2%、0.1%、0.05% 時，發芽率分別為：26%、73%、77%、95%；添加聚丙烯酸濃度0.5%、0.2%、0.1%、0.05%時，發芽率分別為：19%、83%、96%、89%；添加聚麩胺酸濃度0.5%、0.2%、0.1%時，發芽率分別為：11%、61%、67%。在複合試驗的部分，當兩種聚合物複合時，聚麩胺酸濃度提升到0.2% 時，黑麥草之發芽率皆有明顯的下降，PVA 0.05% + γ-PGA 0.1%之發芽率為83%、PVA 0.05% + γ-PGA 0.2%之發芽率為47%、PVA 0.1% + γ-PGA 0.1%之發芽率為92%、PVA 0.1% + γ-PGA 0.2% 之發芽率為61%、PAA 0.1% + γ-PGA 0.1% 之發芽率為89%、PAA 0.1% + γ-PGA 0.2% 之發芽率為45%，三種聚合物複合時，發芽率如下：PVA 0.05% + PAA 0.1% + γ-PGA 0.1% 為93%、PVA 0.1% + PAA 0.1% + γ-PGA 0.1%為92%，結果顯示皆不影響發芽率。盆栽試驗中添加高分子聚合物之試驗組在第22天時PVA 0.05% + PAA 0.1% + γ-PGA 0.1% 及PVA 0.1% + PAA 0.1% + γ-PGA 0.1 % 覆蓋率分別達到79%、94%。在團粒化試驗中，PVA 0.05% + PAA 0.1% + γ-PGA 0.1 % 可團粒粒徑範圍在0.42~0.84 mm內25.5% 的土壤，可針對砂粒土壤做團粒化；PVA 0.1% + PAA 0.1% + γ-PGA 0.1%，可團粒粒徑範圍在0.84~2.0 mm內23.6% 的土壤，可針對黏粒土壤做團粒化。藉由掃描電子顯微鏡觀察添加高分子聚合物於土壤的變化中得知，添加後之土壤其顆粒較大、顆粒之邊界呈圓面狀且顆粒與顆粒間彼此堆疊，顆粒間結構較為緊密，也間接證實了團粒化試驗的結果是正確的。綜上所述本試驗之高分子聚合物可增加土壤顆粒結構，同時亦可增進植物生長，可達到在短期內增加綠意及降低沖蝕之效果，且皆為可分解之高分子聚合物，不會對環境有負面之影響。關鍵詞：植生復育，聚乙烯醇，聚丙烯酸，聚麩胺酸

關鍵字

植生復育；聚乙烯醇；聚丙烯酸；聚麩胺酸

並列摘要

Taiwan's relief that not only long but also narrow hill and the current is swift, so Taiwan has more slopeland . Because of climate change and greenhouse effect is more serious that more clear for extreme climate on global. In Taiwan a torrential rain calamities more critical with every passing day from typhoon , especially slope area exhumed soil that to scour by rain , and to bring about earthflow to create grassland degeneration、exhumed soil and post-disaster recovery become more difficulties, so life and property that to threaten. This research report use Perennial Ryegrass and Bermudagrass to be study grass , and collocation polymer: Polyvinyl alcohol(PVA)、Poly（acrylic acid）(PAA) and gamma-Polyglutamic acid(γ-PGA) , we research concentration proportion compounding for thrive of plant and aggregate of soil that to improve for the soil environment on short time. This study is added different concentration of polymer and discuss that effect of different concentration on slope soil.The result is the concentration of polymer higher, the lower germination percentage was.On the Perennial Ryegrass germination percentage, add concentration of PVA 0.5%、0.2%、0.1%、0.05%, the germination percentage is 26%、73%、77%、95%, add concentration of PAA 0.5%、0.2%、0.1%、0.05%, the germination percentage is 19%、83%、96%、89%, add concentration of γ-PGA 0.5%、0.2%、0.1%, the germination percentage is 11%、61%、67%. There are two polymers to mix of composite test, when concentration of γ-PGA to raise into 0.2% that germination percentage of Perennial Ryegrass is down. germination percentage of PVA 0.05% + γ-PGA 0.1% is 83%、PVA 0.05% + γ-PGA 0.2% is 47%、PVA 0.1% + γ-PGA 0.1% is 92%、PVA 0.1% + γ-PGA 0.2% is 61%、PAA 0.1% + γ-PGA 0.1% is 89%、PAA 0.1% + γ-PGA 0.2% is 45%. There are three polymers to mix of composite test, that germination percentage of Perennial Ryegrass does not effect. germination percentage of PVA 0.05% + PAA 0.1% + γ-PGA 0.1% is 93%、PVA 0.1% + PAA 0.1% + γ-PGA 0.1% is 92%. Add polymer on the pot experiment that coverage of PVA 0.05% + PAA 0.1% + γ-PGA 0.1% is 79% and PVA 0.1% + PAA 0.1% + γ-PGA 0.1 % is 94% on the twenty two days. On the degree of aggregation test, PVA 0.05% + PAA 0.1% + γ-PGA 0.1 % can aggregate 25% soil on the rang between 0.42~0.84 mm, this result that can aggregate sand grain. PVA 0.05% + PAA 0.1% + γ-PGA 0.1 % can aggregate 23.6% soil on the rang between 0.84~2.0 mm, this result that can aggregate clay. We used Scanning Electron Microscope observation that add polymer on the soil, we found soil's granule became bigger and grain-boundary is arc of a circle, and pile up each other between granule. soil structure is closer, so we confirmed the result that degree of aggregation test is true. All in all this study used polymer can to increased soil structure and grew of plant, and lowered erosion in short time.The polymers does biodegradation and can not negative effect for environment. Keywords: Revegetation, PVA, PAA, γ-PGA