張雅文, 許文盛, 韓培, 沈盛彧, 王志剛, 張平倉
(長江科學(xué)院水土保持研究所,430010, 武漢)
無人機(jī)遙感技術(shù)在生產(chǎn)建設(shè)項(xiàng)目水土保持監(jiān)測中的應(yīng)用
——以鄂北水資源配置工程為例
張雅文, 許文盛?, 韓培, 沈盛彧, 王志剛, 張平倉
(長江科學(xué)院水土保持研究所,430010, 武漢)
無人機(jī)遙感技術(shù)在水土保持監(jiān)測工作中的應(yīng)用尚未形成統(tǒng)一有效的方法與標(biāo)準(zhǔn),針對(duì)這一問題,筆者以鄂北地區(qū)水資源配置工程為例,從遙感基礎(chǔ)數(shù)據(jù)獲取、基本監(jiān)測信息提取、監(jiān)測信息應(yīng)用3個(gè)方面,開展水土保持監(jiān)測實(shí)例分析。首先,針對(duì)案例工程的幾個(gè)典型區(qū),在航拍的基礎(chǔ)上,利用Agisoft Photoscan Professional軟件處理原始影像,獲取各區(qū)域的DOM和DEM成果,其水平精度分別可達(dá)0.05和0.2 m。然后,基于DOM和DEM提取監(jiān)測對(duì)象的土地利用類型、位置、面積、體積等信息,構(gòu)建三維虛擬模型。結(jié)果表明計(jì)算機(jī)自動(dòng)識(shí)別更加快速,但存在將監(jiān)測對(duì)象的陰影、苫蓋誤判為植被的問題。最后,將提取的信息逐一應(yīng)用于案例工程的水土保持監(jiān)測工作,直接獲取各典型區(qū)擾動(dòng)土地面積、棄渣體積、苫蓋與否、苫蓋面積等監(jiān)測結(jié)果。無人機(jī)監(jiān)測結(jié)果與運(yùn)用傳統(tǒng)方法監(jiān)測的結(jié)果對(duì)比表明,2種方法的監(jiān)測結(jié)果均滿足相關(guān)技術(shù)要求,但無人機(jī)監(jiān)測效率是傳統(tǒng)人工監(jiān)測效率的3~5倍。成果可為無人機(jī)遙感技術(shù)在水土保持監(jiān)測中的應(yīng)用提供有效的方法借鑒。
無人機(jī)遙感技術(shù); 水土保持監(jiān)測方法; 生產(chǎn)建設(shè)項(xiàng)目; 遙感數(shù)據(jù); 實(shí)例分析
近年來,無人機(jī)遙感技術(shù)的應(yīng)用,為生產(chǎn)建設(shè)項(xiàng)目水土保持監(jiān)測工作提供了一種全新的技術(shù)手段[1-3]。不同于傳統(tǒng)的地面觀測和衛(wèi)星遙感觀測,無人機(jī)遙感技術(shù)可為用戶提供定制化的服務(wù),即圍繞具體目標(biāo),通過設(shè)置飛行規(guī)劃,獲取特定時(shí)間和空間分辨率的數(shù)據(jù)[4-6],進(jìn)而為后續(xù)分析提供支撐;然而,如何將這一技術(shù)切實(shí)應(yīng)用于實(shí)際的水土保持監(jiān)測工作中,并符合相關(guān)規(guī)程規(guī)范的要求,目前還沒有一套成熟的技術(shù)方案[7-9]。對(duì)此,本文針對(duì)鄂北地區(qū)水資源配置工程,開展水土保持監(jiān)測案例分析,并將結(jié)果與運(yùn)用傳統(tǒng)方法監(jiān)測所得到的結(jié)果進(jìn)行對(duì)比,從而評(píng)估無人機(jī)遙感技術(shù)在水土保持監(jiān)測工作中的應(yīng)用潛力和實(shí)際效果。
鄂北地區(qū)水資源配置工程是以丹江口水庫為水源的線狀工程,工程以清泉溝輸水隧洞進(jìn)口為起點(diǎn),線路自西北向東南穿越鄂北崗地,終點(diǎn)為大悟縣城附近的王家沖水庫。干渠途經(jīng)襄陽市的老河口市、襄州區(qū)、棗陽市,隨州市的隨縣、曾都區(qū)、廣水市以及孝感市的大悟縣等地域(圖1)。研究區(qū)處于南襄盆地、桐柏山與大洪山之間,主要為低山、丘陵、垅崗和河谷平原地形。西邊為武當(dāng)山脈,呈東西向展布,至丹江口、老河口及谷城一線以東,武當(dāng)山脈被南襄盆地所切斷,地勢平坦,主要為崗波狀平原及殘丘剝蝕平原;東北邊為桐柏山地,系桐柏山脈的東南余脈,海拔300~500 m,屬中低山蔓延的丘陵;南邊為大洪山脈,海拔300~1 000 m,屬中低山區(qū)??傮w而言,全線壟崗丘陵相間,大致以棗陽沙河為界,沙河以西壟崗地形為主,沙河以東丘陵地形為主。工程劃分為主體工程區(qū)(引水工程區(qū)和水庫工程區(qū))、閘站建筑物區(qū)、排洪建筑物區(qū)、導(dǎo)流工程區(qū)、永久辦公生活區(qū)、存料場區(qū)、棄渣場區(qū)、交通道路區(qū)及施工生產(chǎn)生活區(qū)等;建設(shè)區(qū)面積2 505.80 hm2,其中永久占地341.85 hm2,臨時(shí)占地2 163.95 hm2。區(qū)域內(nèi)土壤類型以潮土、水稻土、黃棕壤和黃褐土為主,屬于輕度土壤侵蝕區(qū),容許土壤流失量為500 t/km2,土壤侵蝕類型主要為水力侵蝕,侵蝕形態(tài)以面蝕為主。
圖1 研究區(qū)域位置圖Fig.1 Location map of the study area
由于鄂北地區(qū)水資源配置工程為線狀工程,占地面積較大,因此本次實(shí)驗(yàn)選擇該項(xiàng)目的典型區(qū)域?qū)嵤┖脚?,包括渠首、紀(jì)洪隧洞出口、16標(biāo)段進(jìn)口處、16標(biāo)段1號(hào)渣場、16標(biāo)段2號(hào)渣場。航拍時(shí)間為2016年5月,航拍采用的設(shè)備為大疆精靈3無人機(jī)搭載非球面鏡片的小型4K相機(jī)。
大疆精靈3是深圳大疆創(chuàng)新科技有限公司在2015年4月8日推出的一款微小型一體航拍無人機(jī),該款無人機(jī)采用四旋翼飛行器,質(zhì)量(含電池及槳)為1 280 g,懸停高度是垂直+/-0.5 m、水平+/-1.5 m,最大上升速度是5 m/s,最大下降速度是3 m/s,最大水平飛行速度是16 m/s,飛行時(shí)間約23 min,云臺(tái)俯仰角為-90°至+30°,穩(wěn)定系統(tǒng)是3-軸(俯仰、橫滾、偏航),采用GPS/GLONASS雙模。
無人機(jī)搭載的非球面鏡片小型4K相機(jī),有效像素是1 240萬,鏡頭FOV是94°20 mm,f/2.8焦點(diǎn)無窮遠(yuǎn),ISO范圍是100~3 200(視頻)和100~1 600(照片),照片最大分辨率是4 000×3 000,電子快門速度是8~1/8 000 s,照片最大分辨率是4 000×3 000,視頻存儲(chǔ)最大碼流是60 Mbps,圖片格式有JPEG和DNG(RAW),視頻格式有MP4/MOV(MPEG-4 AVC/H.264)。
無人機(jī)遙感技術(shù)在應(yīng)用于生產(chǎn)建設(shè)項(xiàng)目水土保持監(jiān)測時(shí),操作流程包括遙感基礎(chǔ)數(shù)據(jù)獲取、基本監(jiān)測信息提取及監(jiān)測信息應(yīng)用等3個(gè)步驟。
2.1 遙感基礎(chǔ)數(shù)據(jù)獲取
案例工程為線狀,涉及的防治責(zé)任范圍較大,外加無人機(jī)可持續(xù)飛行的時(shí)間有限;因此,針對(duì)不同的區(qū)域,飛行操作在自動(dòng)航線設(shè)計(jì)和手動(dòng)控制2種中據(jù)實(shí)選擇。自動(dòng)飛行情況下,飛行高度固定在120 m,航片重疊度設(shè)置在75%以上;手動(dòng)操作情況下,飛行高度約100 m,并根據(jù)當(dāng)時(shí)的風(fēng)速及拍攝區(qū)域面積略有升降,航片重疊度不低于50%。以渠首為例,拍攝的有效影像總數(shù)84張,航線設(shè)計(jì)如圖2所示。照片拍攝后使用Agisoft Photoscan Professional軟件來處理,形成DOM和DEM成果。
圖2 渠首航跡圖Fig.2 Flight plan for the channel head
2.2 基本監(jiān)測信息提取
基于DOM和DEM成果,可提取土地利用類型、監(jiān)測對(duì)象位置、長度、面積和體積等生產(chǎn)建設(shè)項(xiàng)目基本的水土保持監(jiān)測信息,并構(gòu)建三維模型。土地利用類型的識(shí)別有2種方法,一種是目視識(shí)別及勾畫,另一種是計(jì)算機(jī)自動(dòng)分類;監(jiān)測對(duì)象的位置(經(jīng)緯度、高程)、長度與面積等信息,可利用DOM成果,在ArcGIS平臺(tái)中直接提??;監(jiān)測對(duì)象的體積可基于DEM成果,利用微分法估算而得。
2.3 監(jiān)測信息應(yīng)用
圖3 5個(gè)典型區(qū)域DOM和DEM成果Fig.3 DOM and DEM products for five test areas
結(jié)合水土保持監(jiān)測相關(guān)規(guī)范,將提取得到的基本監(jiān)測信息,進(jìn)一步應(yīng)用到實(shí)際的水土保持監(jiān)測工作中。由于本實(shí)驗(yàn)僅實(shí)施一次航拍,無法利用多次信息進(jìn)行變化分析;因此,監(jiān)測信息主要應(yīng)用在如下3個(gè)方面:擾動(dòng)土地狀況監(jiān)測、棄土(石、渣)監(jiān)測、水土保持措施監(jiān)測。其中,擾動(dòng)土地狀況監(jiān)測包括擾動(dòng)范圍、面積、土地利用類型等,棄土(石、渣)監(jiān)測包括臨時(shí)堆土場的數(shù)量、位置、方量、表土剝離、防治措施落實(shí)情況等,水土保持措施監(jiān)測包括工程措施、植物措施及臨時(shí)防治措施的實(shí)施情況。
3.1 遙感基礎(chǔ)數(shù)據(jù)獲取
渠首、紀(jì)洪隧洞出口、16標(biāo)段進(jìn)口處、16標(biāo)段1號(hào)渣場及16標(biāo)段2號(hào)渣場等5個(gè)典型區(qū)域的DOM和DEM成果,分別如圖3所示。在獲取的數(shù)據(jù)精度方面,所有區(qū)域DOM的水平精度達(dá)0.05 m,DEM的水平精度達(dá)0.2 m。
3.2 基本監(jiān)測信息提取
3.2.1 土地利用類型 以16標(biāo)段2號(hào)渣場為例,土地類型信息提取結(jié)果如圖4所示。可以看出,對(duì)于渣場而言,相比目視判別,計(jì)算機(jī)自動(dòng)識(shí)別具備更高的處理效率;但是,由圖4中紅色線條勾選的三塊區(qū)域可以看到,計(jì)算機(jī)自動(dòng)分類也存在明顯的誤判,比如將棄渣的陰影、苫蓋部分識(shí)別成植被,因此有時(shí)對(duì)于計(jì)算機(jī)自動(dòng)識(shí)別結(jié)果還需進(jìn)行人工校正。
3.2.2 監(jiān)測對(duì)象位置 以渠首為例,其開挖面在地下,在ArcGIS中,利用DOM成果獲取的位置信息如圖5所示??梢钥闯觯孜挥贓 111.688°、N 32.647°,其高程為200.83 m(WGS-84坐標(biāo))。
3.2.3 監(jiān)測對(duì)象面積 案例工程典型區(qū)不同監(jiān)測對(duì)象的面積如圖6所示??梢?,紀(jì)洪隧洞出口的施工生產(chǎn)生活區(qū)面積、16標(biāo)段進(jìn)口處施工生產(chǎn)生活區(qū)面積、16標(biāo)2號(hào)渣場的棄渣場面積、16標(biāo)段1號(hào)渣場的棄渣場面積以及16標(biāo)段1號(hào)渣場中2處苫蓋的面積均可明確地給出。
3.2.4 監(jiān)測對(duì)象體積 基于DEM成果,假定棄渣前棄渣場的底部較為平坦(高程無較大變化),利用微分思想,計(jì)算高程乘以柵格大小的累積和,如圖7所示,可近似得到監(jiān)測對(duì)象的體積。以16標(biāo)段1號(hào)渣場和2號(hào)渣場為例,其計(jì)算出的棄渣體積如圖8所示。
3.2.5 三維模型構(gòu)建 利用Agisoft Photoscan Professional軟件,基于構(gòu)建出的項(xiàng)目區(qū)三維模型,可實(shí)現(xiàn)三維效果下的漫游。以紀(jì)洪隧洞出口為例,其三維效果下的漫游如圖9所示。
3.3 監(jiān)測信息應(yīng)用
根據(jù)SL 277—2002《水土保持監(jiān)測技術(shù)規(guī)程》和《生產(chǎn)建設(shè)項(xiàng)目水土保持監(jiān)測規(guī)程(試行)》(辦水?!?015〕139號(hào)),本文將提取的信息主要用于擾動(dòng)土地狀況監(jiān)測、棄土(石、渣)監(jiān)測及水土保持措施監(jiān)測3方面,可為水土流失本底數(shù)據(jù)庫的建立、監(jiān)測成果的提煉與總結(jié)提供有力的支撐。
1)擾動(dòng)土地狀況監(jiān)測結(jié)果:紀(jì)洪隧洞出口的施工生產(chǎn)生活區(qū)擾動(dòng)土地面積是1萬6 562.2 m2,16標(biāo)段進(jìn)口處的施工生產(chǎn)生活區(qū)擾動(dòng)土地面積是5 153.8 m2,16標(biāo)段1號(hào)渣場的棄渣場擾動(dòng)土地面積是4 268.6 m2,16標(biāo)段2號(hào)渣場的棄渣場擾動(dòng)土地面積是1萬9 108.5 m2。
2)棄土(石、渣)監(jiān)測結(jié)果:16標(biāo)段1號(hào)渣場的棄渣體積約為1.1萬m3,16標(biāo)段2號(hào)渣場的棄渣體積約17.2萬m3。
3)水土保持措施監(jiān)測結(jié)果:臨時(shí)措施——16標(biāo)段1號(hào)渣場采取了臨時(shí)苫蓋措施,2處苫蓋面積分別是166.9和1 229.9 m2;16標(biāo)段2號(hào)渣場未采取臨時(shí)苫蓋措施。
生產(chǎn)建設(shè)項(xiàng)目水土保持監(jiān)測傳統(tǒng)的方法主要包括現(xiàn)場測量、定位監(jiān)測、實(shí)地調(diào)查、巡查等,為進(jìn)一步分析無人機(jī)遙感監(jiān)測的效果,本文對(duì)無人機(jī)遙感監(jiān)測結(jié)果與運(yùn)用傳統(tǒng)方法監(jiān)測結(jié)果進(jìn)行對(duì)比,對(duì)比結(jié)果如表1所示。其中,本文所用的傳統(tǒng)監(jiān)測方法主要是現(xiàn)場測量法,面積是利用手持GPS與皮尺實(shí)地測量而得,體積是基于手持GPS、皮尺及測距測高儀實(shí)地測量而得。手持GPS采用中海達(dá)Qcool i3標(biāo)準(zhǔn)版。該儀器單點(diǎn)定位精度5 m,SBAS定位精度3 m;皮尺采用田島(TAJIMA)手提尺100 m,測量精度0.2 cm;測距測高儀采用尼康NIKON手持激光望遠(yuǎn)鏡COOLSHOT 40i測距+測高儀,該儀器測量范圍7.5~590 m,直線距離精度為0.75 m。
分析表1可得,相比于施工單位計(jì)量值,無人機(jī)監(jiān)測結(jié)果和傳統(tǒng)方法監(jiān)測結(jié)果大多控制在10%的差異內(nèi),滿足有關(guān)要求;但從測量效率而言,無人機(jī)方法遠(yuǎn)高于傳統(tǒng)方法,在本實(shí)驗(yàn)中,無人機(jī)監(jiān)測效率是傳統(tǒng)測量效率的3~5倍。
對(duì)于施工生產(chǎn)生活區(qū)擾動(dòng)地表面積,無人機(jī)監(jiān)測值與施工單位計(jì)量值的差異小于傳統(tǒng)方法監(jiān)測值與施工單位計(jì)量值的差異。對(duì)于棄渣場的擾動(dòng)地表面積,無人機(jī)監(jiān)測值與傳統(tǒng)方法監(jiān)測值基本一致。對(duì)于棄渣場的棄渣體積,無人機(jī)監(jiān)測值普遍大于施工單位計(jì)量值,而傳統(tǒng)方法監(jiān)測值小于施工單位計(jì)量值,這是因?yàn)槔脽o人機(jī)監(jiān)測結(jié)果計(jì)算棄渣體積時(shí),把棄渣前的原始地面假定為平面,而本案例的原始地面有部分階梯式凸起;因此,無人機(jī)監(jiān)測結(jié)果偏大。對(duì)于渣場臨時(shí)苫蓋措施,無人機(jī)監(jiān)測值小于施工單位計(jì)量值,但誤差在5%以內(nèi)。利用傳統(tǒng)方法,在苫蓋面積較小時(shí),差異較小,而苫蓋面積較大時(shí),差異也較大。
無人機(jī)遙感技術(shù)應(yīng)用于實(shí)際的水土保持監(jiān)測項(xiàng)目中,有著顯著的優(yōu)勢,包括監(jiān)測效率高、可建立項(xiàng)目區(qū)三維模型等。本文以鄂北地區(qū)水資源配置工程為例,結(jié)合水土保持監(jiān)測相關(guān)技術(shù)規(guī)程,從遙感基礎(chǔ)數(shù)據(jù)獲取、水土保持基本信息提取及應(yīng)用3個(gè)方面,對(duì)這一技術(shù)的操作性及效果進(jìn)行分析。通過監(jiān)測,得到案例工程典型區(qū)域擾動(dòng)土地狀況、棄土(石、渣)情況及部分水土保持措施的落實(shí)情況等,監(jiān)測結(jié)果與施工單位實(shí)際計(jì)量結(jié)果相比,差異≤10%,滿足相關(guān)的技術(shù)要求,效率是傳統(tǒng)實(shí)地測量的3~5倍,這對(duì)于大型線性工程,大大減少人工監(jiān)測成本,提高監(jiān)測效率。另外,針對(duì)特定的水土保持監(jiān)測項(xiàng)目,基于多次定點(diǎn)觀測,可進(jìn)一步獲取項(xiàng)目區(qū)的土壤流失情況、水土流失防治效果等多項(xiàng)指標(biāo),由此,無人機(jī)監(jiān)測技術(shù)可更加全面、具體地應(yīng)用于水土保持監(jiān)測的各項(xiàng)工作中。由于受無人機(jī)一次飛行時(shí)間(螺旋翼通常在0.5 h以內(nèi))與信號(hào)傳輸距離(螺旋翼一般為1~3 km)的限制,對(duì)類似于鄂北地區(qū)水資源配置工程的線性生產(chǎn)建設(shè)項(xiàng)目,進(jìn)行全線路的無人機(jī)遙感監(jiān)測,實(shí)施難度較大,且效率不高;因此針對(duì)此種情況,可基于項(xiàng)目區(qū)衛(wèi)星遙感影像,利用無人機(jī)對(duì)線性工程典型區(qū)的監(jiān)測結(jié)果,通過后期的數(shù)據(jù)解譯與分析來開展,但其精度受衛(wèi)星遙感影像和無人機(jī)監(jiān)測結(jié)果2方面的限制。
圖4 16標(biāo)段2號(hào)渣場Fig.4 The 2th disposal area of the 16th section
圖5 渠首點(diǎn)的位置信息Fig.5 The location of the excavated point in the channel head
圖6 不同監(jiān)測對(duì)象的面積Fig.6 Areas of different monitoring objects
圖7 微分法計(jì)算監(jiān)測對(duì)象的體積Fig.7 Volume calculation for monitoring object using a differential method
由于監(jiān)測結(jié)果在應(yīng)用于實(shí)際時(shí),受監(jiān)測對(duì)象原始地表環(huán)境、無人機(jī)的飛行參數(shù)、飛行路線、飛行高度以及風(fēng)速等多種因素的影響;因此,如何根據(jù)實(shí)際對(duì)監(jiān)測結(jié)果進(jìn)行校正,構(gòu)建一套更為簡便、快速的監(jiān)測數(shù)據(jù)分析方法還需要在后期工作中做進(jìn)一步的探討。
圖8 不同監(jiān)測對(duì)象的體積Fig.8 Volumes of different monitoring objects
序號(hào)No.監(jiān)測對(duì)象Monitoringobject施工單位計(jì)量值Statisticalresultsoftheconstructionorganization無人機(jī)監(jiān)測結(jié)果MonitoringresultsbasedontheUAV傳統(tǒng)方法監(jiān)測結(jié)果Monitoringresultsbasedonthetraditionalmethods監(jiān)測值Monitoringresult差值Difference比例Ratio/%監(jiān)測值Monitoringresult差值Difference比例Ratio/%1紀(jì)洪隧洞出口施工生產(chǎn)生活區(qū)擾動(dòng)土地面積Disturbedlandareasoftheproductionandliv-ingareainconstructionprojectintheexitofJi-hongTunnel(m2)1655016562.212.20.0716612.462.40.38216標(biāo)段進(jìn)口處施工生產(chǎn)生活區(qū)擾動(dòng)土地面積Disturbedlandareasoftheproductionandliv-ingareainconstructionprojectintheentranceof16thsection(m2)51505153.83.80.075201.151.10.99316標(biāo)段1號(hào)渣場擾動(dòng)土地面積Disturbedlandareaofthe1thdisposalareainthe16thsection(m2)40004268.6268.66.724257.3257.36.43416標(biāo)段2號(hào)渣場擾動(dòng)土地面積Disturbedlandareaofthe2thdisposalareainthe16thsection(m2)1830019108.5808.54.4219237.6937.65.12516標(biāo)段1號(hào)渣場棄渣體積Thevolumeofthe1thdisposalareainthe16thsection(104m3)11.10.110.000.85-0.15-15.00
續(xù)表1
注:差值是監(jiān)測值減去施工單位計(jì)量值的差;比例是指差值除以施工單位計(jì)量值。
Note: the difference is the value of the monitoring result-the statistical result of the construction organization; the ratio is the difference to the statistical result of the construction organization.
圖9 紀(jì)洪隧洞出口三維效果下的漫游Fig.9 3D browsing of the exit of Jihong Tunnel
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Application of the UAV remote sensing technology in soil and water conservation monitoring in construction projects: A case study of water resources allocation for the region of north Hubei
ZHANG Yawen, XU Wensheng, HAN Pei, SHEN Shengyu, WANG Zhigang, ZHANG Pingcang
(Division of Soil and Water Conservation, Changjiang River Scientific Research Institute,430010, Wuhan, China)
[Background] The Unmanned Aerial Vehicle (UAV) remote sensing is a new technology for soil and water conservation monitoring. It fills the gap between satellite remote sensing and surface observation, which provides a flexible method for users. However, as to combine this new technology with the criterion and specification in soil and water conservation monitoring in construction projects, more practices are needed. [Methods] We conducted a case study for the application of UAV remote sensing technology in soil and water conservation monitoring. This case study was based on a practical construction project called “Water Resources Allocation for the Region of North Hubei” and was divided into three parts: the acquisition of basic remote sensing data, the extraction of monitoring information and the application of information in monitoring work. First, we took the aerial images of some typical regions of the project, then using the software Agisoft Photoscan Professional, we processed the raw data to generate two products, the Digital Elevation Model (DEM) and Digital Orthophoto Map (DOM) for each region. Finally, based on the criterion and specification in soil and water conservation monitoring in construction projects, the application of extracted information from the DEM and DOM results aims to apply effective information into practical monitoring work [Results] The result showed that horizontal resolutions for all the DOM were less than 0.05 m and those for all the DEM were less than 0.2 m. The computer automatic classification was much faster than visual interpretation for classifying the land cover type. However, the computer automatic method had some problems of misclassifying the shadow of the water soil and coverings into vegetation. Based on the UAV method, the disturbed production and living areas in construction project for the exit of Jihong Tunnel, the entrance of 16thsection, the 1thand 2thdisposal area in the 16thsection were 16 562.2 m2, 5 153.8 m2, 4 268.6 m2and 19 108.5 m2, respectively. The volume of the 1thand 2thdisposal area in the 16thsection was 11 thousand m3and 172 thousand m3. The 1thand 2thtemporary cover area of the 1thdisposal area in the 16thsection was 166.9 m2and 1 229.9 m2, respectively. Compared to the statistical results of the construction organization, the monitoring values based on the UAV and the traditional methods were mostly controlled in 10% of the difference, meeting the relevant requirements. However, the monitoring efficiency of the UAV WAS three to five times of that by the traditional methods. [Conclusions] These monitoring information are all required by the criterion and specification in soil and water conservation monitoring in construction projects. Therefore, by applying UAV remote sensing technology in soil and water conservation monitoring, we may acquire some essential information quickly and easily. Our study shows the feasibility of this method and also reveals that compared to traditional monitoring methods, the information extracted by this method are more accurate and can also save the monitoring cost and improve the monitoring efficiency.
UAV remote sensing technology; soil and water conservation monitoring; construction projects; remote sensing data; case study
2016-09-21
2017-03-28
張雅文(1989—),女,博士研究生。主要研究方向:遙感數(shù)據(jù)處理及應(yīng)用。E-mail:yawen1129@hotmail.com
?通信作者簡介: 許文盛(1983—),男,博士,高級(jí)工程師。主要研究方向:土壤侵蝕與環(huán)境泥沙。E-mail:wenshengxu521@aliyun.com
S157; V279
A
2096-2673(2017)02-0132-08
10.16843/j.sswc.2017.02.017
項(xiàng)目名稱: 水利部“948”計(jì)劃“無人機(jī)載微型高光譜成像儀”(201507)