史志華,劉前進,張含玉,王 玲,黃 萱,方怒放,岳紫健
近十年土壤侵蝕與水土保持研究進展與展望*
史志華1,劉前進2,張含玉2,王 玲1,黃 萱3,方怒放4,岳紫健4
(1. 華中農(nóng)業(yè)大學(xué)資源與環(huán)境學(xué)院,武漢 430070;2. 臨沂大學(xué)資源與環(huán)境學(xué)院,山東臨沂 276000;3. 河海大學(xué)農(nóng)業(yè)科學(xué)與工程學(xué)院,南京 210098;4. 中國科學(xué)院水利部水土保持研究所,陜西楊凌 712100)
在當今生態(tài)文明背景下,土壤侵蝕與水土保持研究迎來了新的發(fā)展機遇和挑戰(zhàn)。本文首先采用文獻計量學(xué)方法,定量分析了近10年來國內(nèi)外土壤侵蝕與水土保持學(xué)科發(fā)展現(xiàn)狀。在此基礎(chǔ)上,結(jié)合社會需求的變化,闡明了學(xué)科發(fā)展需求與存在問題。最后,提出了本學(xué)科研究的重點領(lǐng)域與方向:水文過程與侵蝕產(chǎn)沙機理,土壤侵蝕過程及其定量模擬,全球變化下土壤侵蝕演變及其災(zāi)變機理,社會經(jīng)濟系統(tǒng)—水土流失的互饋過程,以生態(tài)功能提升為主的土壤侵蝕防治,以及土壤侵蝕研究新技術(shù)與新方法等。
土壤侵蝕;水土保持;文獻計量;重點研究領(lǐng)域
土壤侵蝕是土壤及其母質(zhì)在外營力作用下,被破壞、分離、搬運和沉積的過程;水土保持指對外營力造成的土壤侵蝕所采取的預(yù)防和治理措施,以保護水土資源、維持土地生產(chǎn)力,并建立良好生態(tài)環(huán)境的綜合性科學(xué)技術(shù)[1]。土壤侵蝕與水土保持學(xué)科以土壤侵蝕過程為研究對象,揭示其發(fā)生發(fā)展規(guī)律,提出水土保持措施及相關(guān)對策[2]。隨著認識的深入和社會需求的變化,本學(xué)科從對土壤侵蝕現(xiàn)象與影響因子的描述,拓展到對土壤侵蝕過程、預(yù)報模型、水保措施防蝕機理及其適應(yīng)性的研究,并逐步延伸至面源污染、物質(zhì)循環(huán)與全球變化等科學(xué)問題[3]。坡面是土壤侵蝕發(fā)生的基本單元,流域是水土保持的基本單元,因此,本學(xué)科目標是通過主控要素識別和關(guān)鍵過程剖析,揭示坡面和流域尺度上土壤侵蝕過程的發(fā)生發(fā)展規(guī)律并建立預(yù)報模型,闡明水土保持措施的防侵蝕機理與其適應(yīng)性,提出適用于不同區(qū)域的水土保持范式,為土壤侵蝕評價與防治提供科學(xué)依據(jù),服務(wù)于生態(tài)文明建設(shè)和綠色發(fā)展[4]。本文利用文獻計量法,總結(jié)分析了坡面和流域尺度上土壤侵蝕與水土保持學(xué)科近10年研究的核心方向與熱點,明確了我國取得的主要成就及國際地位,探討了未來研究的重點領(lǐng)域與方向,為有針對性開展土壤侵蝕過程與機理研究、解決水土保持關(guān)鍵技術(shù)與瓶頸問題提供參考。
本文以Web of Science(WoS)數(shù)據(jù)庫核心合集作為數(shù)據(jù)源,分別制定坡面和流域尺度上土壤侵蝕與水土保持研究的檢索式TS=(("soil erosion*" or "soil loss")and("hillslope*" or "field*" or "plot*")和TS=(("soil erosion*" or "soil loss*" or sediment*)and(watershed* or catchment* or basin*))。根據(jù)上述檢索式在WoS數(shù)據(jù)庫中檢索到近十年(2010—2019年)土壤侵蝕領(lǐng)域分別在坡面和流域尺度上共發(fā)表英文文獻6 981和7 866篇。
利用文獻可視化軟件CiteSpace分析文獻中的關(guān)鍵詞并生成關(guān)鍵詞共現(xiàn)網(wǎng)絡(luò)圖譜,在圖譜的基礎(chǔ)上采用綜合定量分析方法繪制關(guān)鍵詞聚類視圖,展示土壤侵蝕與水土保持領(lǐng)域的研究熱點與前沿。圖譜中每個節(jié)點大小代表關(guān)鍵詞出現(xiàn)的影響力,節(jié)點越大代表該關(guān)鍵詞出現(xiàn)的次數(shù)越多;節(jié)點的顏色代表關(guān)鍵詞出現(xiàn)的年份,不同顏色的粗細代表頻率;節(jié)點之間的連線代表兩個關(guān)鍵詞共現(xiàn)頻率的高低,連線越粗代表共現(xiàn)頻率越高[5]。
(1)坡面侵蝕過程與機理。坡面侵蝕研究關(guān)注的熱點包括土壤侵蝕動力機制與過程模擬、土壤侵蝕與物質(zhì)遷移、土壤侵蝕與氣候變化以及風(fēng)蝕機理與防治(圖1)。雨滴打擊可直接分散土壤顆粒,也可通過改變徑流能量影響土壤分離過程;土壤分離與輸移過程存在線性互饋機制,其中利用水流剪切力、水流功率等表征水動力學(xué)特性,土壤抗蝕性與臨界剪切力刻畫土壤抗蝕性,挾沙力描述輸沙能力[6]。降雨能量越大,土壤分離出泥沙中的細顆粒含量越高,可吸附更多的養(yǎng)分與污染物[7];侵蝕泥沙呈現(xiàn)雙峰分布,懸移-躍移和推移搬運機制在不同粒級泥沙顆粒上的貢獻率有所差異[8-9],可導(dǎo)致土壤養(yǎng)分、農(nóng)藥、重金屬等物質(zhì)隨徑流泥沙運移的形態(tài)與途徑不同。土壤侵蝕驅(qū)動下,碳氮元素轉(zhuǎn)化以及溫室氣體排放均可能影響全球氣候變化,但影響程度隨降雨、地形、植被、土壤、人為管理等不同而異[10-11]。氣候變化則可通過改變降雨徑流、植被覆蓋和人類活動直接或間接地影響侵蝕過程;氣候變化模式與土壤侵蝕模型耦合,可預(yù)測未來土壤侵蝕的變化與碳循環(huán)響應(yīng),及其對氣候變化的反饋[12-13]。風(fēng)沙流中沙粒的水平和垂直速度均服從Gaussian分布,風(fēng)速、顆粒粒徑是影響躍移沙粒平均速度的重要因子[14],而輸沙率主要受到顆粒含水率、范德華力、風(fēng)沙電場等因素的控制[15]。保護性耕作措施的推廣、地表植被建設(shè)、沙障布設(shè)等措施可在一定程度上抑制風(fēng)蝕危害[16]。借助風(fēng)能示蹤技術(shù),結(jié)合全球氣候變化,有助于風(fēng)蝕模擬預(yù)報與風(fēng)蝕防治[17]。
(2)流域侵蝕產(chǎn)沙過程。流域侵蝕產(chǎn)沙關(guān)注的核心方向包括侵蝕產(chǎn)沙與景觀要素、侵蝕與產(chǎn)沙耦合機制、侵蝕產(chǎn)沙過程模擬以及現(xiàn)代新技術(shù)應(yīng)用(圖2)。降雨作為侵蝕產(chǎn)沙的驅(qū)動因子,其強度、歷時、時空分布等特征對流域侵蝕產(chǎn)沙具有決定性作用[18-19]。流域地形決定了地表徑流的匯流路徑,影響徑流速度、匯水來源[20];植被影響地表反射率、下墊面粗糙度和水分交換,在多個層次上改變降雨徑流,導(dǎo)致侵蝕產(chǎn)沙過程的變化[21]。土地利用通過改變植被覆蓋、土壤性質(zhì)、徑流速率、地形條件等,引起侵蝕發(fā)生及泥沙攔截能力的變化,進而影響侵蝕產(chǎn)沙[22]。景觀異質(zhì)性會使侵蝕產(chǎn)沙具有復(fù)雜的多尺度變異性,將流域作為一個完整的生態(tài)系統(tǒng),量化流域侵蝕與產(chǎn)沙量的關(guān)系,可揭示景觀格局對徑流和泥沙的作用機制[23]。將侵蝕產(chǎn)沙作為一個生態(tài)過程,建立不同尺度上流域景觀與侵蝕產(chǎn)沙過程的關(guān)系,利用水文連通性、源匯相對溝口耗費距離等方法,揭示降雨—徑流—侵蝕產(chǎn)沙過程及滯后機制,初步實現(xiàn)流域侵蝕產(chǎn)沙系統(tǒng)的綜合集成[24]。采用水流挾沙力公式、泥沙連續(xù)方程等,建立注重水沙匯流的侵蝕產(chǎn)沙模型,可深化土壤侵蝕過程與機理的研究,并發(fā)現(xiàn)流域侵蝕-輸移-產(chǎn)沙系統(tǒng)中的泥沙匯集傳遞過程及其機制仍有待深入[25]。技術(shù)的發(fā)展將推動學(xué)科的進步,生物標志物、紅外光譜、核素等技術(shù)被廣泛用于泥沙輸移過程和泥沙來源辨識研究,提高了流域侵蝕源區(qū)的解析精度[26];激光雷達和高時空分辨率遙感技術(shù),可實現(xiàn)地表數(shù)據(jù)的精細化表達,增強土壤侵蝕模擬與可視化[27]。

圖1 坡面侵蝕過程與機理相關(guān)論文關(guān)鍵詞共現(xiàn)關(guān)系圖

圖2 流域侵蝕產(chǎn)沙過程相關(guān)論文關(guān)鍵詞共現(xiàn)關(guān)系圖
(1)坡面侵蝕過程與機理。通過分析近十年國際SCI發(fā)文情況可知(表1),我國2010—2019年在坡面侵蝕過程與機理研究領(lǐng)域共發(fā)表SCI 論文1 515篇,世界排名第二;SCI論文篇均被引約8次,排名第四十;高被引SCI論文數(shù)量為9篇,排名第八。總體而言,雖然我國SCI發(fā)文數(shù)量較多,但高質(zhì)量SCI論文仍然較少,主要研究成果集中在坡面侵蝕形態(tài)演變的臨界條件、陡坡坡面流挾沙力方程、陡坡侵蝕的泥沙分選機理和坡面水土保持措施分類系統(tǒng)四個方面。坡面在降雨徑流作用下,發(fā)生濺蝕、片蝕、細溝侵蝕、淺溝侵蝕、切溝侵蝕等,不同侵蝕過程交互作用導(dǎo)致侵蝕形態(tài)發(fā)生演變。借助REE示蹤技術(shù)、三維激光掃描技術(shù)、激光雷達技術(shù)等,揭示了片蝕—細溝侵蝕—切溝侵蝕演變過程[28-29],探討了侵蝕形態(tài)間發(fā)生演變的臨界閾值[30],明確了重力作用對細溝發(fā)育的重要性[31],發(fā)展了溝蝕發(fā)育過程模型[32-34]。我國46%的坡耕地坡度大于15°,陡坡是侵蝕的重要來源,因此我國在陡坡侵蝕研究方面成果突出:實現(xiàn)了坡面流挾沙力與水動力學(xué)參數(shù)關(guān)系的定量表征,構(gòu)建了陡坡高含沙條件下的坡面流挾沙力方程[6,35-36];基于侵蝕泥沙顆粒分布特性,發(fā)現(xiàn)了陡坡侵蝕中細顆粒以懸移/躍移方式搬運,粗顆粒以滾動方式搬運,明確了滾動搬運在陡坡泥沙輸移中的重要性,揭示了陡坡侵蝕的泥沙分選機理[8,37]。同時,我國水土保持措施多樣,在充分總結(jié)不同措施防蝕機理及其區(qū)域適宜性的基礎(chǔ)上,提出了中國水土保持措施分類系統(tǒng)[38],包括生物措施、工程措施和耕作措施3個一級類型,以及32個二級類型和59個三級類型,成為土壤侵蝕普查和防控的重要基礎(chǔ)。
(2)流域侵蝕產(chǎn)沙過程。近十年我國在流域侵蝕產(chǎn)沙過程研究領(lǐng)域發(fā)表SCI論文數(shù)量為1 494篇,居世界第二;SCI論文引用量約為11次/篇,排名世界第三十四;高被引論文數(shù)量為11篇,排名第三(表2)。相比坡面尺度的研究,我國在流域尺度的研究成果國際影響力更大,在流域侵蝕產(chǎn)沙主控因子識別、侵蝕過程降雨—徑流—泥沙的滯后機理、水蝕區(qū)水保措施的適宜性和水土流失綜合調(diào)控與治理范式方面取得重要進展。地形、土壤、植被、降雨等是影響流域侵蝕產(chǎn)沙的重要環(huán)境因子,鑒于各因子存在非線性復(fù)雜關(guān)系,我國學(xué)者綜合運用非度量多維尺度和偏最小二乘回歸,揭示了土地利用和景觀格局對侵蝕產(chǎn)沙的重要貢獻,辨識了景觀多樣性指數(shù)、聚集度、連結(jié)度、斑塊密度等影響流域產(chǎn)沙的關(guān)鍵景觀格局指數(shù)[23,39],實現(xiàn)了流域侵蝕產(chǎn)沙對環(huán)境因子響應(yīng)的定量表征[40-42];揭示了不同降雨下侵蝕“源匯”功能轉(zhuǎn)化對降雨—徑流—泥沙滯后的作用機制[24,43],建立了流域氣候-人類活動-水沙過程復(fù)雜系統(tǒng)的解耦方法[44-45],定量分離了氣候變化和人類活動對土壤侵蝕的影響[46]。在流域土壤侵蝕防控方面,基于我國主要水蝕區(qū)的土壤侵蝕特點,綜合評估了耕作、生物、工程三大措施的防蝕機理,提出了東北黑土區(qū)、西北黃土區(qū)、西南紫色土區(qū)等水蝕區(qū)的土壤侵蝕綜合調(diào)控與治理范式,成為全世界小流域綜合治理的典范[47]。
近十年來,全球土地利用變化導(dǎo)致土壤侵蝕總量增加2.5%,土壤流失速率高于成土速率1~2個數(shù)量級,土壤侵蝕仍是土壤退化的主導(dǎo)因素[48-49]。我國通過大規(guī)模實施生態(tài)工程,土壤侵蝕呈現(xiàn)出面積持續(xù)減少、強度明顯下降等特點。聯(lián)合國提出的2030年可持續(xù)發(fā)展目標(SDGs),強調(diào)嚴格控制土地退化以保障糧食安全,關(guān)注水土保持生態(tài)系統(tǒng)服務(wù)以促進陸地生態(tài)系統(tǒng)可持續(xù)發(fā)展。可見,傳統(tǒng)的以保障糧食安全為目標的土壤侵蝕防治依舊是研究重點,同時提出了以生態(tài)功能提升為目標的土壤侵蝕防治新需求。因此,土壤侵蝕治理重心應(yīng)從綜合治理轉(zhuǎn)向生態(tài)調(diào)控,以提升生態(tài)功能為主,尋求土壤侵蝕防治與農(nóng)業(yè)高效生產(chǎn)、環(huán)境可持續(xù)發(fā)展的協(xié)同途徑,為國家生態(tài)文明建設(shè)提供科學(xué)依據(jù)[4,33,47]。

在新侵蝕環(huán)境與社會需求下,本學(xué)科面臨諸多問題。侵蝕過程與機理方面:試驗技術(shù)手段限制導(dǎo)致薄層水流流速、流量等難以準確測定,水分入滲、蒸散等難以適時確定;流域景觀異質(zhì)性引起的坡面侵蝕與流域產(chǎn)沙間非線性變化規(guī)律和作用機制仍不清楚;針對我國復(fù)雜侵蝕環(huán)境下的土壤侵蝕過程及相應(yīng)機制尚不明晰[50-52]。水土保持措施配置方面:水土保持防蝕理論滯后于實踐;規(guī)模化農(nóng)業(yè)開發(fā)中生態(tài)、生產(chǎn)與生活功能協(xié)同運行機制不完善;植被地下部分對侵蝕的調(diào)控機理仍不明確,植被重建過程中物種的選擇、配置仍是難點;水保措施防蝕效果的變化規(guī)律及其影響因素仍不清楚[4,53]。區(qū)域或全球尺度侵蝕現(xiàn)狀評估方面:不同尺度下選擇的方法與數(shù)據(jù)及其理論基礎(chǔ)缺少標準與規(guī)范;提高評價精度的技術(shù)與方法體系不健全[54-55]。
降雨和徑流為侵蝕產(chǎn)沙過程提供了能量與載體。因此,對坡面-流域尺度上的水文過程及其機制的深入認識,有助于理解侵蝕產(chǎn)沙機理。降雨產(chǎn)流水文過程及機制經(jīng)由產(chǎn)流閾值、可變源區(qū)發(fā)展至新近提出的水文連通性,侵蝕產(chǎn)沙過程相應(yīng)地從泥沙輸移比、侵蝕源與沉積匯提升至坡面與溝道連續(xù)系統(tǒng)等方面予以解析與模擬[56-57],關(guān)注的重點從將坡面或流域作為一個黑箱、“坡面+溝道”模式發(fā)展至完整的流域系統(tǒng)。基于水文連通性的侵蝕產(chǎn)沙機理,強調(diào)在土壤顆粒或團聚體尺度上分離出的泥沙,以徑流為載體,跨越土體、坡面、流域等多個尺度,形成流域產(chǎn)沙的完整過程[58]。重點研究:不同尺度下水文過程與侵蝕—搬運—沉積的級聯(lián)效應(yīng);水文連通性對流域侵蝕產(chǎn)沙影響機理及其過程模擬。
土壤侵蝕過程具有獨特的水/土界面物理化學(xué)相互作用機制,以及侵蝕地表形態(tài)和環(huán)境要素協(xié)同演化規(guī)律。目前雖然對植被截留、土壤入滲、地表產(chǎn)匯流、侵蝕輸沙、搬運沉積等物理過程進行了表達,但植被截留、土壤入滲過程表達的適用范圍受植被類型、土壤環(huán)境等因素的限制;坡面薄層流特性定量表征及動力過程的解析,仍主要沿用明渠水力學(xué)等鄰近學(xué)科的理論與方法;風(fēng)沙兩相流的相互作用機制及其傳輸過程,主要依賴經(jīng)典力學(xué)和流體力學(xué)予以解析與模擬,學(xué)科理論體系尚不完善。重點研究:含沙水流的水動力學(xué)關(guān)鍵參數(shù)與臨界條件,風(fēng)沙流動力學(xué)特征及沙粒運動過程與機制,重力侵蝕與崩崗發(fā)生的力學(xué)機制與條件;高海拔寒區(qū)融水侵蝕機理與過程模擬,多重外力復(fù)合侵蝕過程與模擬;流域侵蝕—輸移—產(chǎn)沙系統(tǒng)中的泥沙匯集傳遞過程及其機制等。
氣候變化改變了降水、溫度的時空格局,并使地表覆被與人類活動發(fā)生響應(yīng)[59]。變化的降水特性和地表覆被格局,在時空耦合過程中增加了土壤侵蝕過程的不確定性和災(zāi)變風(fēng)險;土地利用格局優(yōu)化、退化生態(tài)系統(tǒng)恢復(fù)重建等應(yīng)對氣候變化的人類活動,則可通過改變陸面的土壤、地理與生態(tài)過程作用于土壤侵蝕過程。同時,侵蝕泥沙搬運過程可使全球生源要素(C、N、P、S)循環(huán)發(fā)生變化,進而影響全球氣候變化。土壤侵蝕過程與全球氣候變化存在互饋機制。重點研究:極端氣候事件對侵蝕過程影響機制及其不確定性;全球變化情勢下土壤侵蝕災(zāi)變閾值及調(diào)控對策;土壤侵蝕對碳“源”、“匯”時空格局的影響;氣候變化下土壤侵蝕發(fā)生發(fā)展趨勢的情景模擬。
土壤侵蝕受自然和社會經(jīng)濟兩個方面因素的共同作用,而社會經(jīng)濟活動及政策對土壤侵蝕具有加劇與控制的雙重作用。但自然要素構(gòu)成的生態(tài)網(wǎng)絡(luò)與社會經(jīng)濟資本、信息等構(gòu)成的社會網(wǎng)絡(luò)存在空間上的錯位[60]。由于社會—生態(tài)網(wǎng)絡(luò)空間錯位,土壤侵蝕驅(qū)動因素的非線性作用更為復(fù)雜,水土資源利用和水土流失治理出現(xiàn)市場失靈。客觀上需要政府從全社會的利益出發(fā),在資源配置和利益分配上起到協(xié)調(diào)作用。重點研究:社會—生態(tài)網(wǎng)絡(luò)結(jié)構(gòu)與功能;農(nóng)業(yè)與非農(nóng)產(chǎn)業(yè)發(fā)展對土壤侵蝕的驅(qū)動機制與作用路徑;社會—生態(tài)網(wǎng)絡(luò)空間錯位對水土流失治理的影響機理;水土保持成本與效益的空間異置與利益權(quán)衡。
在生態(tài)文明建設(shè)背景下,提升生態(tài)功能已成為繼流域綜合治理之后土壤侵蝕防治的新需求。其注重生態(tài)系統(tǒng)的整體性與長期性,統(tǒng)籌流域及區(qū)域的空間分異與功能分區(qū),基于生態(tài)系統(tǒng)的功能與服務(wù),融合使用包括綜合治理在內(nèi)多種土壤侵蝕防治措施、高效農(nóng)業(yè)技術(shù)與流域及區(qū)域管理策略,對侵蝕泥沙的物質(zhì)流、能量流與功能流進行生態(tài)調(diào)控,實現(xiàn)農(nóng)業(yè)生產(chǎn)的高效和環(huán)境的可持續(xù)[4]。重點研究:以生態(tài)系統(tǒng)服務(wù)功能提升為核心的多尺度土壤允許流失量閾值確定;水土保持措施布局整體性優(yōu)化;土壤多樣性對水土保持措施配置的影響機理;水土保持與生態(tài)系統(tǒng)功能的權(quán)衡與協(xié)同機制;土壤侵蝕防治過程中物質(zhì)、能量和信息流演變規(guī)律及模擬。
試驗技術(shù)與方法的進步可為土壤侵蝕過程與動力機制研究、侵蝕模型建立與驗證提供精確數(shù)據(jù)與穩(wěn)健算法。目前試驗設(shè)備、觀測技術(shù)與數(shù)據(jù)處理方法受到諸多限制。人工模擬降雨的雨滴滴譜、終點速度與天然降雨具有一定差異;坡面薄層水流的三維、非均勻與非恒定性,不同于所借鑒的明渠水動力學(xué)條件[8-9,35];缺少從土壤結(jié)構(gòu)穩(wěn)定性等物理化學(xué)層面表征土壤抗蝕性的參數(shù)與方法;生物標志物、氫氧同位素、核素示蹤及紅外光譜等用于識別徑流與泥沙來源具有時效性或非穩(wěn)定性局限[61]。重點研究:薄層水流流速、水深等參數(shù)測量技術(shù)與設(shè)備的研發(fā);土壤結(jié)構(gòu)力學(xué)性質(zhì)測量儀器與方法的改進及其對侵蝕過程量化;徑流泥沙來源示蹤、低空無人飛行器遙感監(jiān)測、人工智能與機器學(xué)習(xí)等技術(shù)在土壤侵蝕研究中的應(yīng)用;區(qū)域與全球尺度水土流失動態(tài)監(jiān)測的大數(shù)據(jù)分析與云網(wǎng)絡(luò)服務(wù)平臺建設(shè)。
近10年國際上對土壤侵蝕與水土保持研究,重點關(guān)注水蝕與風(fēng)蝕動力機制、坡面侵蝕-流域產(chǎn)沙過程與物質(zhì)遷移響應(yīng)、氣候變化與土壤侵蝕互饋機制,以及新方法新技術(shù)的建立與應(yīng)用。我國針對陡坡侵蝕與流域景觀破碎的復(fù)雜侵蝕環(huán)境,識別出了坡面與流域侵蝕產(chǎn)沙主控因子,闡明了土壤分離與輸沙過程的動力機制與滯后機理,凝練了主要水蝕區(qū)水土流失綜合調(diào)控與治理范式。目前傳統(tǒng)的以保障糧食安全為目標的土壤侵蝕防治依舊是研究重點,同時提出了以生態(tài)功能提升為目標的土壤侵蝕防治新熱點。
基于試驗技術(shù)手段限制產(chǎn)流產(chǎn)沙過程準確測定、坡面侵蝕與流域產(chǎn)沙間非線性關(guān)系、水保措施防蝕理論研究落后于實踐、區(qū)域或全球尺度侵蝕評估缺少數(shù)據(jù)與方法支持等問題,提出了本學(xué)科應(yīng)將注重以下研究內(nèi)容:流域侵蝕產(chǎn)沙過程的級聯(lián)效應(yīng),及其對水文連通性的響應(yīng)與模擬;水蝕、風(fēng)蝕、重力侵蝕、融水侵蝕及復(fù)合侵蝕過程中的動力學(xué)機制,特別是水蝕過程中徑流攜沙匯集傳遞過程與機理;全球變化對土壤侵蝕過程與碳“源匯”時空格局的影響與模擬,以及土壤侵蝕災(zāi)變閾值與調(diào)控對策;農(nóng)業(yè)與非農(nóng)產(chǎn)業(yè)發(fā)展過程中土壤侵蝕變化機制、社會—生態(tài)網(wǎng)絡(luò)結(jié)構(gòu)空間錯位對水土流失治理成本與效益的影響機理;基于生態(tài)系統(tǒng)服務(wù)功能提升,確定多尺度土壤允許流失量閾值、優(yōu)化布局水土保持措施配置、明確物質(zhì)、能量和信息流演變規(guī)律及模擬;研發(fā)土壤侵蝕過程監(jiān)測設(shè)備、發(fā)展復(fù)合指紋示蹤與機器學(xué)習(xí)等技術(shù)與方法、注重大數(shù)據(jù)分析與云網(wǎng)絡(luò)服務(wù)平臺建設(shè)。
[ 1 ] Morgan R P C. Soil erosion & conservation [M]. 3rd ed. Oxford:Blackwell Publishing,2005.
[ 2 ] Leng S Y,F(xiàn)eng R G,Li R,et al. Key research issues of soil erosion and conservation in China[J]. Journal of Soil Water and Conservation,2004,18(1):1—6,26. [冷疏影,馮仁國,李銳,等. 土壤侵蝕與水土保持科學(xué)重點研究領(lǐng)域與問題[J]. 水土保持學(xué)報,2004,18(1):1—6,26.]
[ 3 ] Shi Z H,Song C Q. Water erosion processes:A historical review[J]. Journal of Soil and Water Conservation,2016,30(5):1—10. [史志華,宋長青. 土壤水蝕過程研究回顧[J]. 水土保持學(xué)報,2016,30(5):1—10.]
[ 4 ] Shi Z H,Wang L,Liu Q J,et al. Soil erosion:From comprehensive control to ecological regulation[J]. Bulletin of Chinese Academy of Sciences,2018,33(2):198—205. [史志華,王玲,劉前進,等. 土壤侵蝕:從綜合治理到生態(tài)調(diào)控[J]. 中國科學(xué)院院刊,2018,33(2):198—205.]
[ 5 ] Zhao R Y,Xu L M. The knowledge map of the evolution and research frontiers of the bibliometrics[J]. Journal of Library Science in China,2010,36(5):60—68. [趙蓉英,許麗敏. 文獻計量學(xué)發(fā)展演進與研究前沿的知識圖譜探析[J]. 中國圖書館學(xué)報,2010,36(5):60—68.]
[ 6 ] Zhang G H,Shen R C,Luo R T,et al. Effects of sediment load on hydraulics of overland flow on steep slopes[J]. Earth Surface Processes and Landforms,2010,35(15):1811—1819.
[ 7 ] Shi P,Schulin R. Erosion-induced losses of carbon,nitrogen,phosphorus and heavy metals from agricultural soils of contrasting organic matter management[J]. Science of the Total Environment,2018,618:210—218.
[ 8 ] Shi Z H,F(xiàn)ang N F,Wu F Z,et al. Soil erosion processes and sediment sorting associated with transport mechanisms on steep slopes[J]. Journal of Hydrology,2012,454/455:123—130.
[ 9 ] Wang L,Shi Z H,Wang J,et al. Rainfall kinetic energy controlling erosion processes and sediment sorting on steep hillslopes:A case study of clay loam soil from the Loess Plateau,China[J]. Journal of Hydrology,2014,512:168—176.
[ 10 ] Worrall F,Burt T P,Howden N J K. The fluvial flux of particulate organic matter from the UK:The emission factor of soil erosion[J]. Earth Surface Processes and Landforms,2016,41(1):61—71.
[ 11 ] Berhe A A,Harden J W,Torn M S,et al. Linking soil organic matter dynamics and erosion-induced terrestrial carbon sequestration at different landform positions[J]. Journal of Geophysical Research:Biogeosciences,2008,113(G4):https://doi.org/10.1029/2008jg000751.
[ 12 ] Mullan D. Soil erosion under the impacts of future climate change:Assessing the statistical significance of future changes and the potential on-site and off-site problems[J]. Catena,2013,109:234—246.
[ 13 ] Deng L,Liu G B,Shangguan Z P. Land-use conversion and changing soil carbon stocks in China’s‘Grain-for- Green’program:A synthesis[J]. Global Change Biology,2014,20(11):3544—3556.
[ 14 ] Panebianco J E,Buschiazzo D E,Zobeck T M. Comparison of different mass transport calculation methods for wind erosion quantification purposes[J]. Earth Surface Processes and Landforms,2010,35(13):1548—1555.
[ 15 ] Youssef F,Visser S M,Karssenberg D,et al. The effect of vegetation patterns on wind-blown mass transport at the regional scale:A wind tunnel experiment[J]. Geomorphology,2012,159/160:178—188.
[ 16 ] Munson S M,Belnap J,Okin G S. Responses of wind erosion to climate-induced vegetation changes on the Colorado Plateau[J]. Proceedings of the National Academy of Sciences of the United States of America,2011,108(10):3854—3859.
[ 17 ] Wang Z T,Lai Z P,Qu J J. Inverted relief landforms in the Kumtagh Desert of northwestern China:A mechanism to estimate wind erosion rates[J]. Geological Journal,2017,52(1):131—140.
[ 18 ] Bangash R F,Passuello A,Sanchez-Canales M,et al. Ecosystem services in Mediterranean river basin:Climate change impact on water provisioning and erosion control[J]. Science of the Total Environment,2013,458/459/460:246—255.
[ 19 ] Lu X X,Ran L S,Liu S,et al. Sediment loads response to climate change:A preliminary study of eight large Chinese Rivers[J]. International Journal of Sediment Research,2013,28(1):1—14.
[ 20 ] Bracken L J,Wainwright J,Ali G A,et al. Concepts of hydrological connectivity:Research approaches,pathways and future agendas[J]. Earth-Science Reviews,2013,119:17—34.
[ 21 ] Ran L S,Lu X X,Xu J C. Effects of vegetation restoration on soil conservation and sediment loads in China:A critical review[J]. Critical Reviews in Environmental Science and Technology,2013,43(13):1384—1415.
[ 22 ] Fiener P,Auerswald K,van Oost K. Spatio-temporal patterns in land use and management affecting surface runoff response of agricultural catchments—A review[J]. Earth-Science Reviews,2011,106(1/2):92—104.
[ 23 ] Shi Z H,Ai L,Li X,et al. Partial least-squares regression for linking land-cover patterns to soil erosion and sediment yield in watersheds[J]. Journal of Hydrology,2013,498:165—176.
[ 24 ] Fang N F,Shi Z H,Li L,et al. Rainfall,runoff,and suspended sediment delivery relationships in a small agricultural watershed of the Three Gorges area,China[J]. Geomorphology,2011,135(1/2):158—166.
[ 25 ] Chen F X,F(xiàn)ang N F,Wang Y X,et al. Biomarkers in sedimentary sequences:Indicators to track sediment sources over decadal timescales[J]. Geomorphology,2017,278:1—11.
[ 26 ] Vercruysse K,Grabowski R C,Rickson R J. Suspended sediment transport dynamics in Rivers:Multi-scale drivers of temporal variation[J]. Earth-Science Reviews,2017,166:38—52.
[ 27 ] Croke J,Todd P,Thompson C,et al. The use of multi temporal LiDAR to assess basin-scale erosion and deposition following the catastrophic January 2011 Lockyer flood,SE Queensland,Australia[J]. Geomorphology,2013,184:111—126.
[ 28 ] Zhang P,Sun W Y,Tang H W,et al. Advances in morphological evolution and quantitative study of rill on hillslope[J]. Journal of Sediment Research,2017,42(1):68—72. [張攀,孫維營,唐洪武,等. 坡面細溝侵蝕形態(tài)演變與量化研究評述[J]. 泥沙研究,2017,42(1):68—72.]
[ 29 ] He J J,Li X J,Jia L J,et al. Experimental study of rill evolution processes and relationships between runoff and erosion on clay loam and loess[J]. Soil Science Society of America Journal,2014,78(5):1716—1725.
[ 30 ] Zhang Y D,Wu S F,F(xiàn)eng H,et al. Experimental study of rill dynamic development process and its critical dynamic conditions on loess slope[J]. Journal of Sediment Research,2013,38(2):25—32. [張永東,吳淑芳,馮浩,等. 黃土陡坡細溝侵蝕動態(tài)發(fā)育過程及其發(fā)生臨界動力條件試驗研究[J]. 泥沙研究,2013,38(2):25—32.]
[ 31 ] Han P,Ni J R,Hou K B,et al. Numerical modeling of gravitational erosion in rill systems[J]. International Journal of Sediment Research,2011,26(4):403—415.
[ 32 ] Zheng F L,Xu X M,Qin C. A review of gully erosion process research[J]. Transactions of the Chinese Society for Agricultural Machinery,2016,47(8):48—59,116. [鄭粉莉,徐錫蒙,覃超. 溝蝕過程研究進展[J]. 農(nóng)業(yè)機械學(xué)報,2016,47(8):48—59,116.]
[ 33 ] Li R. Research into soil erosion processes and control in major water erosion regions of China[J]. Bulletin of Soil and Water Conservation,2011,31(5):1—6. [李銳. 中國主要水蝕區(qū)土壤侵蝕過程與調(diào)控研究[J]. 水土保持通報,2011,31(5):1—6.]
[ 34 ] Ma X L,Zhang K D,Yang F,et al. Influencing factor analysis of rill erosion section morphology development on slope and its dynamic characteristic experiment[J]. Transactions of the Chinese Society of Agricultural Engineering,2017,33(4):209—216. [馬小玲,張寬地,楊帆,等. 坡面細溝侵蝕斷面形態(tài)發(fā)育影響因素分析及動力特性試驗[J]. 農(nóng)業(yè)工程學(xué)報,2017,33(4):209—216.]
[ 35 ] Zhang G H. Several understandings for sediment transport capacity by overland flow[J]. Advances in Water Science,2018,29(2):151—158. [張光輝. 對坡面徑流挾沙力研究的幾點認識[J]. 水科學(xué)進展,2018,29(2):151—158.]
[ 36 ] Zhang G H,Wang L L,Tang K M,et al. Effects of sediment size on transport capacity of overland flow on steep slopes[J]. Hydrological Sciences Journal,2011,56(7):1289—1299.
[ 37 ] Wang L,F(xiàn)ang N F,Yue Z J,et al. Raindrop size and flow depth control sediment sorting in shallow flows on steep slopes[J]. Water Resources Research,2018,54(12):9978—9995.
[ 38 ] Liu B Y,Liu Y N,Zhang K L,et al. Classification for soil conservation practices in China[J]. Journal of Soil and Water Conservation,2013,27(2):80—84. [劉寶元,劉瑛娜,張科利,等. 中國水土保持措施分類[J]. 水土保持學(xué)報,2013,27(2):80—84.]
[ 39 ] Shi Z H,Huang X D,Ai L,et al. Quantitative analysis of factors controlling sediment yield in mountainous watersheds[J]. Geomorphology,2014,226:193—201.
[ 40 ] Liu Y. Effectiveness of landscape metrics in coupling soil erosion with landscape pattern[J]. Acta Ecologica Sinica,2017,37(15):4923—4935. [劉宇. 景觀指數(shù)耦合景觀格局與土壤侵蝕的有效性[J]. 生態(tài)學(xué)報,2017,37(15):4923—4935.]
[ 41 ] Gao G Y,F(xiàn)u B J,Lü Y H,et al. The effect of land cover pattern on hillslope soil and water loss in the arid and semi-arid region:A review[J]. Acta Ecologica Sinica,2013,33(1):12—22. [高光耀,傅伯杰,呂一河,等. 干旱半干旱區(qū)坡面覆被格局的水土流失效應(yīng)研究進展[J]. 生態(tài)學(xué)報,2013,33(1):12—22.]
[ 42 ] Yan B,F(xiàn)ang N F,Zhang P C,et al. Impacts of land use change on watershed streamflow and sediment yield:An assessment using hydrologic modelling and partial least squares regression[J]. Journal of Hydrology,2013,484:26—37.
[ 43 ] Huang X,F(xiàn)ang N F,Zhu T X,et al. Hydrological response of a large-scale mountainous watershed to rainstorm spatial patterns and reforestation in subtropical China[J]. Science of the Total Environment,2018,645:1083—1093.
[ 44 ] Miao C Y,Ni J R,Borthwick A G L,et al. A preliminary estimate of human and natural contributions to the changes in water discharge and sediment load in the Yellow River[J]. Global and Planetary Change,2011,76(3/4):196—205.
[ 45 ] Huang X,F(xiàn)ang N F,Shi Z H,et al. Decoupling the effects of vegetation dynamics and climate variability on watershed hydrological characteristics on a monthly scale from subtropical China[J]. Agriculture,Ecosystems & Environment,2019,279:14—24.
[ 46 ] Wang S,F(xiàn)u B J,Piao S L,et al. Reduced sediment transport in the Yellow River due to anthropogenic changes[J]. Nature Geoscience,2016,9(1):38—41.
[ 47 ] Cai Q G,Zhu A X,Bi H X. Comprehensive regulation and control paradigm of soil and water loss in Chinese main water erosion areas[M]. Beijing:Science Press,2012. [蔡強國,朱阿興,畢華興. 中國主要水蝕區(qū)水土流失綜合調(diào)控與治理范式[M]. 北京:中國水利水電出版社,2012.]
[ 48 ] Amundson R,Berhe A A,Hopmans J W,et al. Soil and human security in the 21st century[J]. Science,2015,348(6235):1261071.
[ 49 ] Borrelli P,Robinson D A,F(xiàn)leischer L R,et al. An assessment of the global impact of 21st century land use change on soil erosion[J]. Nature Communications,2017,8(1):1—13.
[ 50 ] Poesen J. Soil erosion in the Anthropocene:Research needs[J]. Earth Surface Processes and Landforms,2018,43(1):64—84.
[ 51 ] Fressard M,Cossart E. A graph theory tool for assessing structural sediment connectivity:Development and application in the Mercurey vineyards(France)[J]. Science of the Total Environment,2019,651:2566—2584.
[ 52 ] Gao G Y,F(xiàn)u B J,Zhang J J,et al. Multiscale temporal variability of flow-sediment relationships during the 1950s-2014 in the Loess Plateau,China[J]. Journal of Hydrology,2018,563:609—619.
[ 53 ] Omidvar E,Hajizadeh Z,Ghasemieh H. Sediment yield,runoff and hydraulic characteristics in straw and rock fragment covers[J]. Soil and Tillage Research,2019,194:104324.
[ 54 ] Batista P V G,Davies J,Silva M L N,et al. On the evaluation of soil erosion models:Are we doing enough?[J]. Earth-Science Reviews,2019,197:102898.
[ 55 ] Xiong M Q,Sun R H,Chen L D. A global comparison of soil erosion associated with land use and climate type[J]. Geoderma,2019,343:31—39.
[ 56 ] de Vente J,Poesen J,Verstraeten G,et al. Predicting soil erosion and sediment yield at regional scales:Where do we stand?[J]. Earth-Science Reviews,2013,127:16—29.
[ 57 ] Liu J T,Han X L,Liu J L,et al. Understanding of critical zone structures and hydrological connectivity:A review[J]. Advances in Water Science,2019,30(1):112—122. [劉金濤,韓小樂,劉建立,等. 山坡表層關(guān)鍵帶結(jié)構(gòu)與水文連通性研究進展[J]. 水科學(xué)進展,2019,30(1):112—122.]
[ 58 ] Keesstra S,Nunes J P,Saco P,et al. The way forward:Can connectivity be useful to design better measuring and modelling schemes for water and sediment dynamics?[J]. Science of the Total Environment,2018,644:1557—1572.
[ 59 ] Li Z Y,F(xiàn)ang H Y. Impacts of climate change on water erosion:A review[J]. Earth-Science Reviews,2016,163:94—117.
[ 60 ] Sayles J S,Baggio J A. Social–ecological network analysis of scale mismatches in estuary watershed restoration[J]. Proceedings of the National Academy of Sciences of the United States of America,2017,114(10):E1776-E1785. https://doi.org/10.1073/pnas. 1604405114.
[ 61 ] Collins A L,Williams L J,Zhang Y S,et al. Sources of sediment-bound organic matter infiltrating spawning gravels during the incubation and emergence life stages of salmonids[J]. Agriculture,Ecosystems & Environment,2014,196:76—93.
Study on Soil Erosion and Conservation in the Past 10 Years:Progress and Prospects
SHI Zhihua1, LIU Qianjin2, ZHANG Hanyu2, WANG Ling1, HUANG Xuan3, FANG Nufang4, YUE Zijian4
(1.College of Resources & Environment ofHuazhong Agricultural University, Wuhan 430070, China; 2. College of Resources and Environment, Linyi University, Linyi, Shandong 276000, China; 3. College of Agricultural Science and Engineering, Hohai University, Nanjing 210098, China; 4. Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shaanxi 712100, China)
Under the background of ecological civilization, soil erosion and conservation face new opportunities and challenges nowadays. We employed a bibliometric analysis on the research of soil erosion and conservation in the past ten years. The results summarized the research tendency and hotspots, and presented China’s main achievements and international status in this field. Considering social needs, we pointed out the main existing problems for scientific researches on soil erosion and conservation. Then, we identified the front scientific issues, including the coupling mechanisms of hydrology and soil erosion, the soil erosion process and modeling, the soil erosion evolution and its catastrophic mechanism under global change, the mutual feedback between socio-economy and soil erosion, the soil conservation for ecological function improvement, and the new technologies and methods for soil erosion research.
Soil erosion; Soil conservation; Bibliometric; Key research issues
S157
A
10.11766/trxb202002240070
史志華,劉前進,張含玉,王玲,黃萱,方怒放,岳紫健. 近十年土壤侵蝕與水土保持研究進展與展望[J]. 土壤學(xué)報,2020,57(5):1117–1127.
SHI Zhihua,LIU Qianjin,ZHANG Hanyu,WANG Ling,HUANG Xuan,F(xiàn)ANG Nufang,YUE Zijian. Study on Soil Erosion and Conservation in the Past 10 Years:Progress and Prospects[J]. Acta Pedologica Sinica,2020,57(5):1117–1127.
* 國家杰出青年科學(xué)基金項目(41525003)資助Supported by the National Science Fund for Distinguished Young Scholars of China(No. 41525003)
史志華,男,博士,教授,主要從事土壤侵蝕與水土保持教學(xué)和研究工作。E-mail:pengshi@mail.hzau.edu.cn
2020–02–24;
2020–04–28;
網(wǎng)絡(luò)首發(fā)日期(www.cnki.net):2020–06–04
(責(zé)任編輯:檀滿枝)