經歷本次研究對河床質調查工作可能遭遇問題與有待釐清事項有初 步瞭解，許多成果僅以相關文獻為基礎，提供策略後再以頭前溪模擬缺乏 量化說明，因此仍須進一步驗證。茲就建議事項說明如后：
1.頭前溪因砂石開採過量影響河川自然變遷，並非良好示範案例，應以 受人為因素影響較低之河川建立範例。
2.初步判斷網格法可有條件運用於台灣河床質調查，但本研究驗證試驗 數量不足，應收集更多試驗成果進一步比較。另由於頭前溪顆粒分佈 廣泛，造成網格法分析有所限制，本文提出修正方法雖有些微助益但 尚有很大進步空間，有待進一步改良取樣或分析方法提高結果正確性 與效率。
3.網格法適用性評估僅與一組體積法結果比較有其盲點。單一位置體積 法結果亦可能代表性不足，Mosley and Tindale 指出體積樣品由多組 次樣品組成一大樣品進行篩分析所得結果比僅以單一位置取得樣品 進行篩分析更具代表性。且國內慣例取樣一立方公尺所得樣品重量約 兩公噸，以台灣河床顆粒分佈情況而言此重量未達ISO 標準或 Church 之個人建議準則。因此欲確實比較網格法與體積法結果應先建立體積 法標準規範使其代表性增高，如此才能確保比較結果正確性。
4.橫向部分因地形展現不同河床質組成為明確事實。以取樣可行性與代
表性而言，於邊灘或沙洲進行取樣較理想。但若能建立各種不同地形 間河床質差異關係（D50），則當調查空間受到限制時可以渠道邊緣取 樣結果推估河道內灘、沙洲與主深槽處河床質代表粒徑。此部分尚須 以河相為單位，透過試驗建立各種河相於橫向地貌上河床質差異基 準。
5.縱向分段準則初步評估可行，如何落實於河川管理工作有待進行長期 觀察，進一步驗證系統之良窳。
6.河床質調查頻率係以礫石河床傳輸特性評估，但不同河川是否存在差 異有待進一步驗證。應設計試驗長期觀察以檢驗此推論正確性，進而 建立台灣地區標準。
7.網格法所得結果理應與體積法表層樣品比較，但礫石河床表層定義困 難，使體積法結果亦存在不確定性。建議可將網格法調查結果與透過 洪水觀測後反推結果相較，方能得到最真實結果。故可於設有測站河 段進行試驗，進一步探討與修正取樣方法。
7.由於河床上礫石經常以瓦覆狀堆疊，啟動底床上任一顆粒均需擾動其 周遭顆粒造成互制結構破壞後才會發生，因此底床顆粒排列緊密程度 影響顆粒初始初始運動狀態遠勝於顆粒及配分佈。建議可嘗試以碎形 維度之叢聚維度評估顆粒排列關係，提供更符合實際狀況之分析參 數。
8.調查需求數量可透過河相學選擇取樣位置，在分析取樣位置出現週期 決定。但同一地貌再經歷不同洪水後因被淹沒範圍不同，導致同一沈 積環境內河床質差異。對於單一取樣點以及特定區域取樣代表性與數 量已有學者進行研究，但未含蓋所有河相特徵，且由不同學者提出結 果可發現具代表性取樣數量會因環境不同產生差異。建議引入統計方 法分析台灣河川狀況，建立台灣地區標準。透過此二方法結合可完整 評估調查最低需求數量。
9.本研究網格法取樣採用童軍繩取代採樣膠帶，但童軍繩具伸縮性容易 產生操作誤差。建議使用較粗繩索或剛性較佳之材質作為網格建立工 具，以降低操作誤差發生可能性。
10.礫石河床因常存在粗粒化情形，使調查工作不得不區分表底層進 行，表層網格法較體積法便利且有效率，因此若能確認表、底層材料 關連性，則可大幅節省河床質調查工作所需資原。過去研究顯示表 底、層材料間關係薄弱，但此仍為值得改進與突破之細節。
11.本研究網格法採用樣品選擇標準為顆粒尺寸小於 8mm 者已鄰近大於 8mm 顆粒取代，此準則嚴重影響粒徑分佈尾端分佈。建議當取樣顆 粒粒徑小於8mm 時，僅作小於 8mm 之記錄，並將其發生次數列入分 析，此次數所佔機率理論上應與體積篩分析法通過8mm 之含量接 近，如此能更正確評估粒徑分佈曲線。另可嘗試於取樣區域表面選擇
較細顆粒（19mm 以下）樣品 10 公斤，以實驗室篩分析結果補充網 格法8mm 以下細顆粒曲線之不足。
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