生植物種植施工難點

　　水生植(zhi)物(wu)(wu)種(zhong)植(zhi)施(shi)工難點(dian)--水生植(zhi)物(wu)(wu)在園林景觀(guan)、河道治理(li)、人(ren)造(zao)濕地(di)和濕地(di)保護(hu)工程(cheng)中得(de)到了(le)廣泛應用，本(ben)文就常(chang)水位(wei)、波浪(lang)及種(zhong)植(zhi)土等水生植(zhi)物(wu)(wu)施(shi)工中的(de)難點(dian)問題進行討論。

　　常水位問題

　　從事園林工(gong)程施(shi)(shi)工(gong)作(zuo)業(ye)人員對水(shui)(shui)(shui)(shui)位(wei)(wei)問題往往職業(ye)敏(min)感性(xing)較差，沒有引起足(zu)夠重視。殊不知，許多(duo)水(shui)(shui)(shui)(shui)生植(zhi)(zhi)(zhi)(zhi)物(wu)種(zhong)植(zhi)(zhi)(zhi)(zhi)后大面(mian)積死(si)亡(wang)，其中一(yi)個重要原因(yin)(yin)是(shi)水(shui)(shui)(shui)(shui)位(wei)(wei)控(kong)制得(de)不好。種(zhong)植(zhi)(zhi)(zhi)(zhi)施(shi)(shi)工(gong)作(zuo)業(ye)時(shi)，由(you)于項目尚未(wei)竣工(gong)水(shui)(shui)(shui)(shui)體沒有完全蓄(xu)水(shui)(shui)(shui)(shui)，或在春天枯水(shui)(shui)(shui)(shui)期，水(shui)(shui)(shui)(shui)位(wei)(wei)往往偏低。施(shi)(shi)工(gong)管理人員通(tong)常(chang)(chang)(chang)認為水(shui)(shui)(shui)(shui)生植(zhi)(zhi)(zhi)(zhi)物(wu)不能離開水(shui)(shui)(shui)(shui)，水(shui)(shui)(shui)(shui)深一(yi)點淺(qian)一(yi)點無所(suo)謂(wei)，常(chang)(chang)(chang)把水(shui)(shui)(shui)(shui)生植(zhi)(zhi)(zhi)(zhi)物(wu)種(zhong)植(zhi)(zhi)(zhi)(zhi)在設(she)計(ji)等(deng)(deng)深線(xian)(xian)以(yi)下或等(deng)(deng)高(gao)線(xian)(xian)以(yi)上。到蓄(xu)水(shui)(shui)(shui)(shui)時(shi)或水(shui)(shui)(shui)(shui)位(wei)(wei)漲(zhang)到常(chang)(chang)(chang)水(shui)(shui)(shui)(shui)位(wei)(wei)時(shi)，由(you)于種(zhong)得(de)太(tai)深，挺(ting)水(shui)(shui)(shui)(shui)植(zhi)(zhi)(zhi)(zhi)物(wu)被(bei)“淹死(si)”，浮葉植(zhi)(zhi)(zhi)(zhi)物(wu)葉子浮不出(chu)(chu)水(shui)(shui)(shui)(shui)面(mian)被(bei)“悶死(si)”，沉水(shui)(shui)(shui)(shui)植(zhi)(zhi)(zhi)(zhi)物(wu)因(yin)(yin)水(shui)(shui)(shui)(shui)深光照過弱而(er)“餓死(si)”；或由(you)于種(zhong)得(de)離常(chang)(chang)(chang)水(shui)(shui)(shui)(shui)位(wei)(wei)線(xian)(xian)高(gao)出(chu)(chu)過多(duo)，挺(ting)水(shui)(shui)(shui)(shui)植(zhi)(zhi)(zhi)(zhi)物(wu)被(bei)“旱(han)死(si)”。可見常(chang)(chang)(chang)水(shui)(shui)(shui)(shui)位(wei)(wei)線(xian)(xian)是(shi)水(shui)(shui)(shui)(shui)生植(zhi)(zhi)(zhi)(zhi)物(wu)的生命線(xian)(xian)，在實際(ji)施(shi)(shi)工(gong)作(zuo)業(ye)時(shi)對常(chang)(chang)(chang)水(shui)(shui)(shui)(shui)位(wei)(wei)線(xian)(xian)要給予(yu)足(zu)夠的重視。建議在種(zhong)植(zhi)(zhi)(zhi)(zhi)施(shi)(shi)工(gong)放樣前先用水(shui)(shui)(shui)(shui)準儀在現場確(que)定出(chu)(chu)常(chang)(chang)(chang)水(shui)(shui)(shui)(shui)位(wei)(wei)線(xian)(xian)，在植(zhi)(zhi)(zhi)(zhi)物(wu)配(pei)置時(shi)把各種(zhong)植(zhi)(zhi)(zhi)(zhi)物(wu)的水(shui)(shui)(shui)(shui)深適應(ying)性(xing)作(zuo)為硬(ying)指標來考(kao)慮。

　　波浪問題

　　江、河(he)、湖岸(an)(an)浪(lang)蝕是(shi)這些水(shui)體(ti)(ti)順向演(yan)(yan)(yan)替的(de)自(zi)然過(guo)程，浪(lang)蝕淤(yu)積(ji)(ji)也是(shi)影響這些水(shui)體(ti)(ti)壽命(ming)的(de)重要因(yin)素。在自(zi)然界隨(sui)著(zhu)水(shui)體(ti)(ti)的(de)演(yan)(yan)(yan)替，岸(an)(an)坡趨緩并沉(chen)積(ji)(ji)土壤，為水(shui)生(sheng)(sheng)植物的(de)生(sheng)(sheng)存繁衍創造(zao)了條(tiao)件，植物的(de)生(sheng)(sheng)長減緩了水(shui)岸(an)(an)的(de)侵蝕，是(shi)演(yan)(yan)(yan)替的(de)阻(zu)力，但植物體(ti)(ti)的(de)腐爛沉(chen)積(ji)(ji)、水(shui)中有機質含量的(de)大幅度提高，豐(feng)富(fu)了水(shui)體(ti)(ti)營(ying)養，提高了水(shui)體(ti)(ti)生(sheng)(sheng)物量，從(cong)這個角(jiao)度說水(shui)生(sheng)(sheng)植物對整(zheng)個水(shui)體(ti)(ti)的(de)演(yan)(yan)(yan)替是(shi)有貢獻的(de)。

　　人們在水(shui)(shui)體岸(an)(an)(an)(an)邊種植(zhi)(zhi)(zhi)(zhi)水(shui)(shui)生(sheng)(sheng)(sheng)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)的一(yi)(yi)個(ge)重要(yao)作(zuo)用(yong)(yong)(yong)是減(jian)緩波(bo)(bo)浪(lang)(lang)對岸(an)(an)(an)(an)線的侵(qin)蝕(shi)，保證正常的水(shui)(shui)體環境。水(shui)(shui)生(sheng)(sheng)(sheng)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)自然成(cheng)了固(gu)岸(an)(an)(an)(an)和(he)浪(lang)(lang)蝕(shi)這對矛盾(dun)的焦點。 商(shang)住(zhu)區和(he)公共綠地(di)內部的小(xiao)(xiao)水(shui)(shui)系一(yi)(yi)般來說范圍(wei)小(xiao)(xiao)、禁(jin)航、水(shui)(shui)流緩慢，對岸(an)(an)(an)(an)線沖(chong)刷、侵(qin)蝕(shi)較小(xiao)(xiao)，對水(shui)(shui)生(sheng)(sheng)(sheng)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)的種植(zhi)(zhi)(zhi)(zhi)生(sheng)(sheng)(sheng)長影響(xiang)不大。江河湖(hu)泊等水(shui)(shui)體由(you)于(yu)(yu)風浪(lang)(lang)、船形(xing)波(bo)(bo)或水(shui)(shui)流急速(su)沖(chong)刷給水(shui)(shui)生(sheng)(sheng)(sheng)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)的種植(zhi)(zhi)(zhi)(zhi)、生(sheng)(sheng)(sheng)存帶來很大困難(nan)。如(ru)風浪(lang)(lang)和(he)船形(xing)波(bo)(bo)將會(hui)(hui)直接或通過堤(di)岸(an)(an)(an)(an)反射，強烈(lie)地(di)直接拍打或搖動植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)體，從而使(shi)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)葉片破碎、莖(jing)被(bei)(bei)折斷，甚至植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)體被(bei)(bei)連根拔(ba)起(qi)(qi)，影響(xiang)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)的生(sheng)(sheng)(sheng)長甚或導致其死亡。因此種植(zhi)(zhi)(zhi)(zhi)時要(yao)強加考察，根據(ju)波(bo)(bo)浪(lang)(lang)特(te)點在種植(zhi)(zhi)(zhi)(zhi)時采取相應的消(xiao)(xiao)浪(lang)(lang)、護岸(an)(an)(an)(an)加固(gu)技術(shu)措施，待水(shui)(shui)生(sheng)(sheng)(sheng)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)恢復后(hou)挺水(shui)(shui)植(zhi)(zhi)(zhi)(zhi)物(wu)(wu)(wu)(wu)能(neng)(neng)起(qi)(qi)到一(yi)(yi)定(ding)的消(xiao)(xiao)浪(lang)(lang)作(zuo)用(yong)(yong)(yong)，它的根系也(ye)能(neng)(neng)起(qi)(qi)到一(yi)(yi)定(ding)的護坡固(gu)岸(an)(an)(an)(an)作(zuo)用(yong)(yong)(yong)。 消(xiao)(xiao)浪(lang)(lang)固(gu)岸(an)(an)(an)(an)根據(ju)不同岸(an)(an)(an)(an)線和(he)波(bo)(bo)浪(lang)(lang)強度等可采用(yong)(yong)(yong)不同形(xing)式。對于(yu)(yu)開闊湖(hu)泊，迎風岸(an)(an)(an)(an)、波(bo)(bo)浪(lang)(lang)高的岸(an)(an)(an)(an)線可考慮使(shi)用(yong)(yong)(yong)消(xiao)(xiao)浪(lang)(lang)缽，但消(xiao)(xiao)浪(lang)(lang)缽離(li)岸(an)(an)(an)(an)邊距(ju)離(li)應當在150米(mi)以內。對于(yu)(yu)湖(hu)面(mian)小(xiao)(xiao)，波(bo)(bo)浪(lang)(lang)不大的岸(an)(an)(an)(an)線可采用(yong)(yong)(yong)松(song)木(mu)樁、毛竹樁，它們既(ji)消(xiao)(xiao)浪(lang)(lang)又固(gu)岸(an)(an)(an)(an)，是較好的選擇(ze)。也(ye)可和(he)園(yuan)林景(jing)觀(guan)相結(jie)合采用(yong)(yong)(yong)岸(an)(an)(an)(an)線疊(die)石處(chu)理，疊(die)石錯落有致，既(ji)滿足(zu)園(yuan)林景(jing)觀(guan)需要(yao)也(ye)能(neng)(neng)消(xiao)(xiao)浪(lang)(lang)和(he)固(gu)岸(an)(an)(an)(an)，但造(zao)價偏高，占水(shui)(shui)系面(mian)積較大，對行洪可能(neng)(neng)會(hui)(hui)產(chan)生(sheng)(sheng)(sheng)一(yi)(yi)定(ding)影響(xiang)。

　　種植土問題

　　種(zhong)植土(tu)是除浮水(shui)植物(wu)以外水(shui)生(sheng)植物(wu)賴(lai)以生(sheng)存(cun)的(de)(de)養(yang)分來(lai)源，對挺水(shui)植物(wu)來(lai)說又是支撐植物(wu)體的(de)(de)基礎。水(shui)生(sheng)植物(wu)對種(zhong)植土(tu)的(de)(de)要(yao)求是以滿(man)足上述(shu)兩項功能來(lai)確定(ding)。一(yi)般來(lai)說原水(shui)體的(de)(de)淤泥(ni)是較(jiao)為理(li)想的(de)(de)種(zhong)植土(tu)，對新開挖(wa)的(de)(de)人造(zao)濕地可結合周邊(bian)河流(liu)湖(hu)泊清(qing)淤填(tian)(tian)淤，如淤泥(ni)難以采辦，在(zai)南(nan)方(fang)可用水(shui)稻(dao)(dao)田的(de)(de)表層土(tu)，在(zai)北方(fang)如缺水(shui)稻(dao)(dao)田也(ye)可選用肥力較(jiao)高旱地耕作(zuo)層土(tu)。對粘性重的(de)(de)種(zhong)植土(tu)回填(tian)(tian)后要(yao)給予(yu)一(yi)定(ding)時(shi)間的(de)(de)沉(chen)降、硬(ying)(ying)化(hua)。對浪(lang)大和(he)硬(ying)(ying)質(zhi)堤壩(ba)的(de)(de)岸線(xian)要(yao)注(zhu)意，回填(tian)(tian)的(de)(de)種(zhong)植土(tu)極(ji)易(yi)(yi)被波(bo)浪(lang)侵蝕掉。在(zai)原有水(shui)體中(zhong)種(zhong)植水(shui)生(sheng)植物(wu)時(shi)也(ye)要(yao)考慮底泥(ni)的(de)(de)發(fa)育問題，種(zhong)植前一(yi)定(ding)要(yao)到水(shui)里探查(cha)底泥(ni)情(qing)況。迎風(feng)岸、硬(ying)(ying)質(zhi)堤壩(ba)岸邊(bian)的(de)(de)底泥(ni)易(yi)(yi)被侵蝕，往(wang)往(wang)缺少軟性底泥(ni)的(de)(de)發(fa)育，這(zhe)對種(zhong)植水(shui)生(sheng)植物(wu)極(ji)為不利，應先行采用消浪(lang)措施(shi)，減少波(bo)浪(lang)，然后再回填(tian)(tian)種(zhong)植土(tu)，才(cai)能種(zhong)植。