圖書典藏及影音數位平台

政府為能適度加以開發河川區域內土地之使用以提高該土地經濟價值，民眾可依水利法及河川管理辦法相關規定向河川管理機關申請於河川區域內土地種植、圍築漁塭、施設休閒遊憩場所等經營使用，本屬美意。然而台灣地區河川多屬坡陡蜿蜒河川，豐枯水期流量變化大，在枯水期流量小而形成深槽流路，在豐水期常因颱風暴雨河水高漲及當時河川地理環境（如種植作物、及親水空間植栽等）的變化，導致深槽流路改變及分歧，易影響現有河防建造物。高灘地種植利用情形普遍，雖然依據相關實務經驗，高灘地種植植生可以減緩河川流路變遷趨勢，局部保護高灘地之流失。然對於河防安全，則有改變河道糙率，抬高洪水位之負面效應。 鑑於本局轄內大安溪河川區域中常見農作物之種植使用行為，其種植範圍或有超出所申請區域，乃至於鄰近深槽處，容易造成水流不穩定。根據現行最新修訂公告之河川區域種植規定（103年3月），本計畫研擬藉由進行植生範圍及植生密度分析，進行本局於大安溪所轄河段河川區域種植行為影響之河防安全風險評估，並完成大安溪種植區域許可種植分級之劃設，以利相關從業人員審查、設計使用。

Students on both domestic and planting density and planting case permission to collect, including high floodplain roughness coefficient of vegetated mainly by the different height of the governed, and to explore the shrubs planting spacing and density. 103 years according to the current "river area planted provision amended regulations," Daan River growing region is divided into five levels, and draw Daan River planting area of river membership plans. In addition, the comparison of the results with the grading designation of the status of crops distributed comparative evaluation. Via the river commons inventory report showed that the current planting Daan River estuary to reach most of section 32 to a low stem crop-based; section 32 to section 40 after 99 years of survey data that river commons as Daan River main high stem crop distribution area, the third He Chuanju Republic 100 years after the change handle river area review, the Department remaining sporadic high stem crops area, the main planting oranges, grapes and pears based. Upper reaches and tributaries of the river and Wushi Creek Jingshan, the survey now be present but sporadic cultivation, mostly weeds and miscellaneous forest. The project has been carried out under the existing provisions on planting river area, in one of the downstream river plant raw range Status dimensional analysis, and partial two-dimensional mathematical analysis based on high water beach location, compare the results of Daan River river area planted rating designation of work, and the investigation carried out crops now work to analyze the density of the main crops grown and the number of trees planted and spacing. And planting area in Daan River Bridge and Zhuolan River Bridge eradicate dimensional analysis and simulation of water before and after treatment, due to the large high floodplain and river deep groove gap, although slightly lower the water level and flow rate can be, but the overall trend is not erosion obvious. The Risk Assessment of River Security: based on historical flood data, changes in water management and erosion, stabilizing river through flood capacity and other factors fix a local river water two-dimensional mathematical analysis as Lanshih River Bridge on the Lower Reach, social Tail River dike , and embankment footing dimensional stability analysis of water according to the results of mathematical analysis.