李樹(shù)寶 張麗娜 王樹(shù)森 馬迎梅 張苗苗 馬成功 于勝利
摘要:研究森林經(jīng)營(yíng)方式對(duì)不同林齡落葉松林林下枯落物及土壤水源涵養(yǎng)能力的影響,為該研究區(qū)落葉松人工林經(jīng)營(yíng)與水土保持措施的制定提供理論依據(jù)。2021年8月在赤峰市旺業(yè)甸林場(chǎng)選取近自然經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)和未經(jīng)營(yíng)措施下的落葉松幼齡林、近熟林和成熟林為研究對(duì)象,采用野外調(diào)查取樣與室內(nèi)實(shí)驗(yàn)分析相結(jié)合的方法,對(duì)比分析不同經(jīng)營(yíng)方式下落葉松幼齡林、近熟林和成熟林林下枯落物與土壤的持水能力,并運(yùn)用熵權(quán)法對(duì)落葉松林枯落物及土壤水源涵養(yǎng)能力進(jìn)行綜合評(píng)價(jià)。結(jié)果表明,9種樣地類型枯落物總厚度介于2.37~5.83 cm,總蓄積量介于11.27~37.07 t/hm2,不同林齡落葉松林林下枯落物最大持水量和有效持水量的變化趨勢(shì)由大到小順序均為成熟林、近熟林、幼齡林;不同經(jīng)營(yíng)方式落葉松林林下枯落物最大持水量和有效持水量由大到小順序均為未經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)、近自然經(jīng)營(yíng);不同林齡落葉松林林下土壤總孔隙度、毛管孔隙度、飽和持水量和毛管持水量的變化規(guī)律由大到小順序均為幼齡林、成熟林、近熟林;不同經(jīng)營(yíng)方式落葉松林林下土壤孔隙度及持水量的變化規(guī)律由大到小均為近自然經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)、未經(jīng)營(yíng);落葉松林在未經(jīng)營(yíng)措施下成熟林階段林下水源涵養(yǎng)能力最高,在常規(guī)經(jīng)營(yíng)措施下幼齡林階段林下水源涵養(yǎng)能力次之,在常規(guī)經(jīng)營(yíng)措施下近熟林階段林下水源涵養(yǎng)能力最低。
關(guān)鍵詞:森林經(jīng)營(yíng);落葉松;林齡;水源涵養(yǎng)
中圖分類號(hào):S715.7文獻(xiàn)標(biāo)識(shí)碼:A文章編號(hào):1006-8023(2023)02-0012-10
Effects of Forest Management Methods on Litter and Soil Water Conservation
Capacity of Larix principis-rupprechtii Plantation of Different Ages
LI Shubao1,2, ZHANG Lina1,3, WANG Shusen1,2*, MA Yingmei1,3, ZHANG Miaomiao1,2, MA Chenggong4, YU Shengli4
(1.College of Desert Control Science and Technology, Inner Mongolia Agricultural University, Hohhot 010018, China;
2.Key Laboratory of State Forestry and Grassland Administration for Desert Ecosystem Protection and Restoration,
Inner Mongolia Agricultural University, Hohhot 010018, China; 3.Inner Mongolia Key Laboratory of Aeolian Physics
and Desertification Engineering, Hohhot 010018, China; 4.Wangyedian Experimental Forest Farm, Chifeng 024423, China)
Abstract:The effects of forest management methods on the understory litter and soil water conservation capacity of Larix principis-rupprechtii forests of different ages were studied to provide a theoretical basis for the formulation of Larix principis-rupprechtii plantation management and soil and water conservation measures in the study area. In August 2021, young forests, near-mature forests and mature forests of Larix principis-rupprechtii ?under near-natural management, conventional management and non-management measures were selected as the research objects in Wangyedian Forest Farm, Chifeng City, the method of field survey and sampling combined with indoor experimental analysis was used to compare and analyze the water holding capacity of understory litter and soil in young Larix principis-rupprechtii forest, near-mature forest and mature forest under different management methods, and the entropy weight method was used to comprehensively evaluate the litter and soil water conservation capacity of Larix principis-rupprechtii forest. The results showed that: the total thickness of litter in 9 sample plots ranged from 2.37 cm to 5.83 cm, and the total volume of litter ranged from 11.27 t/hm2 to 37.07 t/hm2. The maximum and effective water holding capacity of litter under different ages of Larix principis-rupprechtii forests
收稿日期:2022-07-08
基金項(xiàng)目:內(nèi)蒙古地區(qū)多功能樹(shù)種選育及擴(kuò)繁關(guān)鍵技術(shù)研究與示范項(xiàng)目(2019GG004)
第一作者簡(jiǎn)介:李樹(shù)寶,碩士研究生。研究方向?yàn)樗帘3峙c荒漠化防治。Email: 964959354@qq.com
*通信作者:王樹(shù)森,博士,教授。研究方向?yàn)樗帘3峙c荒漠化防治。Email: wsswtt@126.com
引文格式:李樹(shù)寶,張麗娜,王樹(shù)森,等.森林經(jīng)營(yíng)方式對(duì)不同林齡落葉松林枯落物及土壤水源涵養(yǎng)能力的影響[J].森林工程,2023,39(2):12-21.
LI S B, ZHANG L N, WANG S S, et al. Effects of forest management methods on litter and soil water conservation capacity of Larix principis-rupprechtii plantation of different ages[J]. Forest Engineering,2023,39(2):12-21.
showed the trend of mature forest>near-mature forest>young forest. The maximum and effective water holding capacity of litter under Larix principis-rupprechtii forest under different management modes showed the order of non-management>conventional management>near natural management. Soil total porosity, capillary porosity, saturated water capacity and capillary water capacity under different ages of Larix principis-rupprechtii stands had the regularities of young forest>mature forest>near-mature forest. Soil porosity and water holding capacity of Larix principis-rupprechtii forest under different management patterns showed the change rule of near-natural management>conventional management>non-management. Under non-management measures, the understory water conservation capacity of mature forest stage of Larix principis-rupprechtii forest was the highest; under conventional management measures, the understory water conservation capacity of young forest stage was second, and the understory water conservation capacity of near-mature forest stage under conventional management measures was the lowest.
Keywords:Forest management; Larix principis-rupprechtii; forest age; water conservation
0引言
水源涵養(yǎng)能力是森林生態(tài)系統(tǒng)中重要的生態(tài)功能之一[1],是由森林林冠層、枯落物層和土壤層共同作用的復(fù)雜過(guò)程,其中枯落物層和土壤層作為主要表現(xiàn)層,通過(guò)截留、吸收和蓄積實(shí)現(xiàn)對(duì)降雨的再分配,從而達(dá)到調(diào)節(jié)徑流、保持水土、涵養(yǎng)水源和凈化水質(zhì)的作用[2-4]。森林經(jīng)營(yíng)是對(duì)現(xiàn)有森林進(jìn)行科學(xué)培育以提高森林產(chǎn)量和質(zhì)量的生產(chǎn)活動(dòng)總稱,按照不同的擇伐撫育方式可分為近自然經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)和未經(jīng)營(yíng)[5]。近自然經(jīng)營(yíng)也稱目標(biāo)樹(shù)經(jīng)營(yíng),即伐除影響目標(biāo)樹(shù)生長(zhǎng)的干擾樹(shù),目標(biāo)樹(shù)達(dá)到目的徑級(jí)時(shí)進(jìn)行單株擇伐;常規(guī)經(jīng)營(yíng)是指“間密留勻、砍小留大、砍劣留優(yōu)”,采伐強(qiáng)度較大;無(wú)干擾經(jīng)營(yíng)是指封山育林,排除人為干擾,自然更新。目前,關(guān)于該內(nèi)容的研究多集中于森林經(jīng)營(yíng)對(duì)林分結(jié)構(gòu)[5]、植物多樣性[6]、生物量和碳儲(chǔ)量[7]方面的影響。在撫育初期,僅有趙波等[8]和賽克等[9]在森林經(jīng)營(yíng)對(duì)森林持水能力的影響方面進(jìn)行了研究,后期森林經(jīng)營(yíng)方式如何影響落葉松(Larix principis-rupprechtii)人工林枯落物及土壤的水源涵養(yǎng)能力未見(jiàn)報(bào)道。因此,本研究以近自然經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)和未經(jīng)營(yíng)措施下的落葉松幼齡林、近熟林和成熟林為研究對(duì)象,采用野外調(diào)查取樣與室內(nèi)實(shí)驗(yàn)分析相結(jié)合的方法,對(duì)比分析不同經(jīng)營(yíng)方式下落葉松幼齡林、近熟林和成熟林林下枯落物與土壤的持水能力,并運(yùn)用熵權(quán)法對(duì)落葉松林林下水源涵養(yǎng)能力進(jìn)行綜合評(píng)價(jià),為該研究區(qū)落葉松人工林經(jīng)營(yíng)與水土保持措施的制定提供理論依據(jù)。
1研究地區(qū)與研究方法
1.1研究區(qū)概況
研究區(qū)位于內(nèi)蒙古自治區(qū)赤峰市喀喇沁旗旺業(yè)甸實(shí)驗(yàn)林場(chǎng),地理坐標(biāo)為118°09′~118°30′E,41°21′~41°39′N。地勢(shì)西南高東北低,平均海拔800~1 890 m。屬大陸季風(fēng)氣候,年平均氣溫4.2 ℃,年平均降水量300~500 mm。土壤類型以典型棕壤為主。林場(chǎng)林地面積24 668.2 hm2,有林地面積22 397.1 hm2,有林地共有12種優(yōu)勢(shì)樹(shù)種,主要包括落葉松、油松(Pinus tabuliformis)、白樺(Betula platyphylla)、蒙古櫟(Quercus mongolica)和山楊(Populus davidiana)等,其中落葉松面積4 835.4 hm2,占有林地面積的21.61%。
1.2研究方法
1.2.1樣地設(shè)置與調(diào)查取樣
2021年8月于旺業(yè)甸實(shí)驗(yàn)林場(chǎng)選擇近自然經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)和未經(jīng)營(yíng)措施下的落葉松幼齡林、近熟林和成熟林為研究對(duì)象,分別設(shè)置半徑為13.82 m、面積為600 m2的圓形樣地,各樣地類型3個(gè)重復(fù),共計(jì)27塊樣地。在各樣地內(nèi)呈品字形設(shè)置3個(gè)50 cm×50 cm的枯落物樣方,利用鋼卷尺分別對(duì)其未分解層和半分解層厚度進(jìn)行測(cè)量和記錄,并按照未分解層和半分解層分別收集枯落物樣品。在各樣地類型附近分別設(shè)置3個(gè)土壤剖面,分為0~10、>10~20和>20~40 cm環(huán)刀、鋁盒取樣,每層3個(gè)重復(fù)。研究區(qū)森林經(jīng)營(yíng)方式、林齡情況與前人的研究一致[9]。樣地基本情況見(jiàn)表1。
1.2.2枯落物蓄積量與持水能力測(cè)定
枯落物蓄積量采用烘干法測(cè)定[10]??萋湮锍炙芰Σ捎檬覂?nèi)浸泡法測(cè)定,稱取烘干枯落物樣品50 g裝入紗網(wǎng)袋中,在充分浸泡0.5、1、2、4、8、12、24 h時(shí)將紗網(wǎng)袋從容器內(nèi)依次取出,靜置至無(wú)重力水滴落迅速稱重并記錄,為減少實(shí)驗(yàn)誤差,設(shè)置3個(gè)空紗網(wǎng)袋作為對(duì)照。計(jì)算各樣地類型枯落物持水量、持水速率和攔蓄量等指標(biāo)[2,4,11],相關(guān)計(jì)算公式如下。
R1=M24-M0M0×100%。(1)
W1=R1×M。(2)
W2=(0.85R1-R0)×M。(3)
式中:R1為枯落物最大持水率,%;M24為枯落物浸水24 h后的質(zhì)量,g;M0為枯落物浸水前烘干質(zhì)量,g;W1為枯落物最大持水量,t/hm2;M為枯落物蓄積量,t/hm2;W2為枯落物有效攔蓄量,t/hm2;0.85為有效攔蓄系數(shù);R0為枯落物自然含水率,%。
1.2.3土壤物理性質(zhì)與持水能力測(cè)定
各樣地類型土壤容重采用環(huán)刀法測(cè)定;土壤孔隙度及持水量采用環(huán)刀浸泡法測(cè)定[1],相關(guān)計(jì)算公式如下。
Wc=10 000×Pc×H。(4)
Wn=10 000×Pn×H。(5)
Wt=Wc+Wn。(6)
式中:Wc為土壤毛管持水量,t/hm2;Wn為土壤有效持水量,t/hm2;Wt為土壤和飽和持水量,t/hm2;Pc為土壤毛管孔隙度,%;Pn為土壤非毛管孔隙度,%;H為土層深度,m。
1.2.4水源涵養(yǎng)能力綜合評(píng)價(jià)
本研究采用熵權(quán)法對(duì)9種類型落葉松林林下水源涵養(yǎng)能力進(jìn)行綜合評(píng)價(jià)[1-2,12],相關(guān)計(jì)算公式如下。
rij=xij-min(xij)max(xij)-min(xij)(i=1,…,m;
j=1,…,n)。(7)
rij=max(xij)-xijmax(xij)-min(xij)。(8)
pij=rij∑nj=1rij。(9)
Hi=-1lnn∑nj=1pijlnpij(假定Pij=0時(shí),pijlnpij=0)。(10)
Wi=1-Him-∑mi=1Hi。(11)
WCI=∑mi=1Wirij。(12)
式中:xij為第i個(gè)評(píng)價(jià)指標(biāo)對(duì)應(yīng)第j個(gè)林分類型;rij為標(biāo)準(zhǔn)化后的對(duì)應(yīng)指標(biāo)值;pij為第i項(xiàng)指標(biāo)下第j個(gè)評(píng)價(jià)對(duì)象指標(biāo)值的比重;m為評(píng)價(jià)指標(biāo)數(shù);n為樣地類型數(shù);Hi為第i項(xiàng)指標(biāo)的熵值;Wi為第i項(xiàng)指標(biāo)的權(quán)重;WCI為水源涵養(yǎng)能力綜合指數(shù)。
2結(jié)果與分析
2.1枯落物層水源涵養(yǎng)能力
2.1.1枯落物厚度及蓄積量
由圖1(a)可知,各樣地類型枯落物總厚度介于2.37~5.83 cm,均值為3.61 cm;受林齡與分解速率影響,落葉松幼齡林林下枯落物未分解層厚度大于半分解層,而近熟林和成熟林林下枯落物厚度與之相反。落葉松不同林齡林下枯落物總厚度由大到小表現(xiàn)為成熟林、幼齡林、近熟林;不同經(jīng)營(yíng)方式的變化規(guī)律由大到小表現(xiàn)為未經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)、近自然經(jīng)營(yíng)。
由圖1(b)可知,各樣地類型枯落物總蓄積量介于11.27~37.07 t/hm2,且落葉松幼齡林、近熟林和成熟林林下枯落物半分解層總蓄積量均高于未分解層。隨著林齡的增長(zhǎng),落葉松林下枯落物總蓄積量的變化規(guī)律由大到小表現(xiàn)為成熟林(30.41 t/hm2)、近熟林(19.02 t/hm2)、幼齡林(13.04 t/hm2);受采伐強(qiáng)度的影響,不同經(jīng)營(yíng)方式下落葉松林下枯落物總蓄積量的變化趨勢(shì)表現(xiàn)為未經(jīng)營(yíng)、近自然經(jīng)營(yíng)、常規(guī)經(jīng)營(yíng)。
2.1.2枯落物持水能力
由表2可以看出,隨著林齡的增長(zhǎng),落葉松林林下枯落物最大持水量呈逐漸增加的趨勢(shì),由大到小順序?yàn)槌墒炝郑?2.28 t/hm2)、近熟林(57.43 t/hm2)、幼齡林(44.47 t/hm2),且未分解層和半分解層也表現(xiàn)出相同的變化趨勢(shì);不同經(jīng)營(yíng)方式使得落葉松林林下枯落物最大持水量的變化規(guī)律由大到小依次為未經(jīng)營(yíng)(71.37 t/hm2)、常規(guī)經(jīng)營(yíng)(58.49 t/hm2)、近自然經(jīng)營(yíng)(54.31 t/hm2),其未分解層和半分解層變化與之相同。隨著落葉松的生長(zhǎng),其林下枯落物最大持水率呈現(xiàn)先增大后減小的趨勢(shì),由大到小依次為近熟林(313.88%)、幼齡林(313.45%)、成熟林(271.84%);不同經(jīng)營(yíng)方式落葉松林林下枯落物最大持水率由大到小順序?yàn)槲唇?jīng)營(yíng)(328.03%)、常規(guī)經(jīng)營(yíng)(323.43%)、近自然經(jīng)營(yíng)(247.71%);由于枯落物自身含水量及分解程度存在較大差異,除近熟林樣地類型以外,其余各類型樣地落葉松林林下枯落物最大持水率均表現(xiàn)出未分解層大于半分解層的變化規(guī)律。
由表3可知,不同林齡落葉松林下枯落物有效攔蓄量的變化規(guī)律由大到小順序?yàn)槌墒炝郑?1.08 t/hm2)、近熟林(25.20 t/hm2)、幼齡林(22.07 t/hm2),而有效攔蓄率則表現(xiàn)出隨林齡的增長(zhǎng)呈現(xiàn)先增大后減小的變化趨勢(shì),且未分解層有效攔蓄率大于半分解層;從森林經(jīng)營(yíng)方式來(lái)看,落葉松林林下枯落物有效攔蓄量由大到小順序?yàn)槲唇?jīng)營(yíng)、常規(guī)經(jīng)營(yíng)、近自然經(jīng)營(yíng),有效攔蓄率由大到小順序?yàn)槌R?guī)經(jīng)營(yíng)、未經(jīng)營(yíng)、近自然經(jīng)營(yíng),其未分解層有效攔蓄率也大于半分解層。
2.1.3枯落物持水過(guò)程
由圖2可以看出,浸水初期,不同樣地類型林下枯落物未分解層、半分解層持水量均迅速增加,隨著浸水時(shí)間的增加,其持水量緩慢增加。究其原因可能是在浸泡過(guò)程中,在0.5~2 h干燥的枯落物迅速吸水,持水量迅速增加,隨著浸泡時(shí)間的增加,枯落物吸水量到達(dá)一定程度后,其吸持水分的能力出現(xiàn)降低的趨勢(shì),持水量的增加逐漸變緩。浸泡時(shí)間為8 h時(shí),枯落物的持水量接近最大值,之后隨著浸泡時(shí)間的增加其持水量變化較小,直到枯落物持水量達(dá)到飽和狀態(tài)。不同分解階段枯落物層持水量與浸泡時(shí)間之間存在W=a·lnt+b的對(duì)數(shù)關(guān)系,式中:t為浸泡時(shí)間,h;W為浸水t小時(shí)內(nèi)枯落物的持水量,t/hm2;a為方程系數(shù);b為方程常數(shù)項(xiàng)。
由圖3可知,9種樣地類型林下不同分解層枯落物吸水速率隨浸泡時(shí)間的增加而降低,且其吸水速率隨時(shí)間的變化趨勢(shì)基本一致,均表現(xiàn)為0~2 h吸水速率迅速降低,之后緩慢下降,浸水8 h之后基本穩(wěn)定。究其原因可能是吸水速率隨著持水量的增加逐漸減小。9種樣地類型林下枯落物不同分解層吸水速率與浸泡時(shí)間存在y=k·tn的關(guān)系式,式中:y為浸水t小時(shí)內(nèi)的吸水速率;k為方程系數(shù);n為指數(shù)。
2.2土壤層水源涵養(yǎng)能力
2.2.1土壤物理性質(zhì)
由圖4(a)可知,9種樣地類型林下土壤容重介于0.88~1.43 g/cm3,均值為1.13 g/cm3,且各樣地類型林下土壤容重均隨土層深度的增加而增大。從不同林齡角度分析可知,落葉松林林下土壤容重由大到小順序?yàn)榻炝?、成熟林、幼齡林;從不同經(jīng)營(yíng)方式角度分析可知,落葉松林林下土壤容重由小到大順序?yàn)榻匀唤?jīng)營(yíng)、常規(guī)經(jīng)營(yíng)、未經(jīng)營(yíng)。由圖4(b)可以看出,研究區(qū)各樣地類型林下土壤總孔隙度和毛管孔隙度的變化范圍分別為39.45~61.89%和38.53~60.33%;且隨土層深度的增加,各樣地類型土壤總孔隙度表現(xiàn)出減小的趨勢(shì)。不同林齡落葉松林林下土壤總孔隙度由大到小順序?yàn)橛g林(55.32%)、成熟林(47.26%)、近熟林(44.97%);不同經(jīng)營(yíng)方式落葉松林林下土壤總孔隙度由大到小順序?yàn)榻匀唤?jīng)營(yíng)、常規(guī)經(jīng)營(yíng)、未經(jīng)營(yíng)的大小順序。
2.2.2土壤持水能力
由圖5可知,不同林齡對(duì)落葉松林林下土壤持水量的影響表現(xiàn)為幼齡林顯著高于成熟林和近熟林,其土壤毛管持水量、飽和持水量分別介于425.46~518.12 t/hm2和449.69~553.24 t/hm2,且不同林齡落葉松林林下土壤飽和持水量由大到小順序?yàn)橛g林、成熟林、近熟林。不同經(jīng)營(yíng)方式落葉松林林下土壤毛管持水量介于461.09~481.38 t/hm2,均值為467.90 t/hm2;且林下土壤飽和持水量由大到小順序?yàn)榻匀唤?jīng)營(yíng)(500.10 t/hm2)、常規(guī)經(jīng)營(yíng)(489.53 t/hm2)、未經(jīng)營(yíng)(485.89 t/hm2)。
2.3水源涵養(yǎng)能力綜合評(píng)價(jià)
基于枯落物層厚度、蓄積量、最大持水量、最大持水率、有效攔蓄量、有效攔蓄率、土壤層容重、毛管孔隙度、非毛管孔隙度、總孔隙度、毛管持水量、有效持水量和飽和持水量13個(gè)指標(biāo)的實(shí)測(cè)數(shù)據(jù),采用熵權(quán)法對(duì)不同類型落葉松林林下水源涵養(yǎng)能力進(jìn)行綜合評(píng)價(jià)。評(píng)價(jià)結(jié)果見(jiàn)表4。
不同森林經(jīng)營(yíng)方式落葉松幼齡林林下水源涵養(yǎng)能力綜合評(píng)價(jià)由大到小表現(xiàn)為常規(guī)經(jīng)營(yíng)(0.153)、近自然經(jīng)營(yíng)(0.129)、未經(jīng)營(yíng)(0.112),落葉松近熟林林下水源涵養(yǎng)能力由大到小表現(xiàn)為近自然經(jīng)營(yíng)(0.082)、未經(jīng)營(yíng)(0.072)、常規(guī)經(jīng)營(yíng)(0.060),落葉松成熟林林下水源涵養(yǎng)能力由大到小表現(xiàn)為未經(jīng)營(yíng)(0.189)、常規(guī)經(jīng)營(yíng)(0.126)、近自然經(jīng)營(yíng)(0.078);近自然經(jīng)營(yíng)措施對(duì)不同林齡落葉松林下水源涵養(yǎng)能力的影響由大到小表現(xiàn)為幼齡林、近熟林、成熟林,常規(guī)經(jīng)營(yíng)措施對(duì)不同林齡落葉松林下水源涵養(yǎng)能力的影響由大到小表現(xiàn)為幼齡林、成熟林、近熟林,未經(jīng)營(yíng)措施對(duì)不同林齡落葉松林下水源涵養(yǎng)能力的影響由大到小表現(xiàn)為成熟林、幼齡林、近熟林。綜上所述,落葉松林在未經(jīng)營(yíng)措施下成熟林階段林下水源涵養(yǎng)能力最高,在常規(guī)經(jīng)營(yíng)措施下幼齡林階段林下水源涵養(yǎng)能力次之,在常規(guī)經(jīng)營(yíng)措施下近熟林階段林下水源涵養(yǎng)能力最低。
3結(jié)論與討論
3.1討論
枯落物厚度及蓄積量受林分類型、林齡、砍伐程度和環(huán)境等諸多因素的影響[2,13],本研究中9種樣地類型林下枯落物厚度和蓄積量的變化范圍分別為:2.37~5.83 cm和11.27~37.07 t/hm2,這與梁文俊等[14]對(duì)華北落葉松林枯落物水文效應(yīng)的研究結(jié)果相近??萋湮镒畲蟪炙亢陀行r蓄量是表征枯落物層持水能力和涵養(yǎng)水源特性的重要指標(biāo)[1-2],且枯落物有效攔蓄量是體現(xiàn)攔蓄能力最直接的指標(biāo)[14]。研究表明,3種森林經(jīng)營(yíng)方式成熟林林下枯落物的有效攔蓄量均為最大值,隨著林齡的增長(zhǎng),林下枯落物蓄積量不斷增加,枯落物的攔蓄能力也隨之得到加強(qiáng),這與楊佳慧等[2]的研究結(jié)果一致。各樣地類型林下枯落物不同分解層持水量與浸水時(shí)間呈對(duì)數(shù)函數(shù)關(guān)系,吸水速率與浸水時(shí)間呈冪指數(shù)函數(shù)關(guān)系,該研究結(jié)果與現(xiàn)有諸多研究結(jié)果一致[15-17]。森林經(jīng)營(yíng)措施和植物物種組成等的改變以及諸多生態(tài)過(guò)程的變化均會(huì)對(duì)土壤生態(tài)系統(tǒng)造成一定的影響[18]。土壤層研究結(jié)果表明,9種樣地類型林下土壤容重均隨土層深度的增加而增大,土壤孔隙度均隨土層深度的增加而減小,相關(guān)研究者也曾得出相似的變化規(guī)律[19-21]。研究區(qū)各樣地類型土壤容重介于0.88~1.43 g/cm3,均值為1.13 g/cm3,與萬(wàn)麗[5]的研究結(jié)果相比,各樣地類型林下土壤容重均有所減小,即隨著經(jīng)營(yíng)年限的增加,土壤孔隙度均有所提高,且近自然經(jīng)營(yíng)和常規(guī)經(jīng)營(yíng)措施在林木生長(zhǎng)期有利于植被生長(zhǎng),從而改變土壤的疏松程度。本研究中的9種樣地類型林下土壤持水能力的變化規(guī)律與土壤孔隙度的變化規(guī)律一致,眾多學(xué)者也曾得出類似的研究結(jié)果[22-25]。熵權(quán)法能夠剔除主觀因素的影響,客觀判斷各評(píng)價(jià)指標(biāo)的相對(duì)重要性,可以解決因內(nèi)涵不同而不能相加的缺點(diǎn),且目前已有諸多研究者將熵權(quán)法應(yīng)用到水源涵養(yǎng)能力評(píng)價(jià)過(guò)程中,彭玉華等[26]將熵權(quán)法應(yīng)用到混交林水源涵養(yǎng)功能評(píng)價(jià)研究中;楊良辰等[12]使用熵權(quán)法對(duì)沿壩地區(qū)典型林分類型枯落物層與土壤層水源涵養(yǎng)能力進(jìn)行綜合評(píng)價(jià),類似這樣的研究還有很多[1,27],均可以說(shuō)明熵權(quán)法在水源涵養(yǎng)能力評(píng)價(jià)中的可行性和科學(xué)性。
3.2結(jié)論
1)研究區(qū)落葉松林下枯落物總厚度介于2.37~5.83 cm,總蓄積量介于11.27~37.07 t/hm2,且其最大持水量和有效持水量由大到小順序?yàn)槲唇?jīng)營(yíng)、常規(guī)經(jīng)營(yíng)、近自然經(jīng)營(yíng)。
2)近自然經(jīng)營(yíng)措施下落葉松林下土壤總孔隙度、毛管孔隙度、飽和持水量、毛管持水量均大于常規(guī)經(jīng)營(yíng)和未經(jīng)營(yíng)措施。
3)落葉松林在未經(jīng)營(yíng)措施下成熟林階段林下水源涵養(yǎng)能力最高,在常規(guī)經(jīng)營(yíng)措施下幼齡林階段林下水源涵養(yǎng)能力次之,在常規(guī)經(jīng)營(yíng)措施下近熟林階段林下水源涵養(yǎng)能力最低。
【參考文獻(xiàn)】
[1]張佳楠,張建軍,張海博,等.晉西黃土區(qū)典型林分水源涵養(yǎng)能力評(píng)價(jià)[J].北京林業(yè)大學(xué)學(xué)報(bào),2019,41(8):105-114.
ZHANG J N, ZHANG J J, ZHANG H B, et al. Water conservation capacity of typical forestlands in the Loess Plateau of Western Shanxi Province of Northern China[J]. Journal of Beijing Forestry University, 2019, 41(8): 105-114.
[2]楊家慧,譚偉,卯光憲,等.黔中不同齡組柳杉人工林枯落物水源涵養(yǎng)能力綜合評(píng)價(jià)[J].水土保持學(xué)報(bào),2020,34(2):296-301,308.
YANG J H, TAN W, MAO G X, et al. Water conservation ability of litter in Cryptomeria fortunei plantation with different age groups in central Guizhou[J]. Journal of Soil and Water Conservation, 2020, 34(2): 296-301, 308.
[3]艾彪,黃云,朱元皓,等.贛南丘陵區(qū)典型林分水源涵養(yǎng)功能評(píng)價(jià)[J].水土保持通報(bào),2021,41(1):197-205.
AI B, HUANG Y, ZHU Y H, et al. Evaluation of water conservation capacity of litter and soil layer in typical forest stands in hilly region of southern Jiangxi Province[J]. Bulletin of Soil and Water Conservation, 2021, 41(1): 197-205.
[4]侯貴榮,畢華興,魏曦,等.黃土殘塬溝壑區(qū)刺槐林枯落物水源涵養(yǎng)功能綜合評(píng)價(jià)[J].水土保持學(xué)報(bào),2019,33(2):251-257.
HOU G R, BI H X, WEI X, et al. Comprehensive evaluation of water conservation function of litters of Robinia pseudoacacia forest lands in gully region on Loess Plateau[J]. Journal of Soil and Water Conservation, 2019, 33(2): 251-257.
[5]萬(wàn)麗.不同森林經(jīng)營(yíng)模式對(duì)林分結(jié)構(gòu)與生態(tài)特征的影響:以赤峰旺業(yè)甸林場(chǎng)為例[D].北京:北京林業(yè)大學(xué),2015.
WAN L. Effects of different forest management patterns on stand structure and ecological characteristics in Wangyedian Experimental Forest Farm, Chifeng[D]. Beijing: Beijing Forestry University, 2015.
[6]王春霞.近自然經(jīng)營(yíng)對(duì)旺業(yè)甸森林灌草植物多樣性影響的研究[D].呼和浩特:內(nèi)蒙古農(nóng)業(yè)大學(xué),2017.
WANG C X. Research on effect of close-to-nature management on the shrub and herb species diversity of Wangyedian[D]. Hohhot: Inner Mongolia Agricultural University, 2017.
[7]張濤,羅于洋,王樹(shù)森,等.近自然經(jīng)營(yíng)方式對(duì)不同林齡油松人工林碳儲(chǔ)量的影響[J].水土保持通報(bào),2018,38(2):40-45.
ZHANG T, LUO Y Y, WANG S S, et al. Effects of natural alike management on carbon storage in Pinus tabuliformis plantations under different forest age[J]. Bulletin of Soil and Water Conservation, 2018, 38(2): 40-45.
[8]趙波,羅于洋,王樹(shù)森,等.近自然經(jīng)營(yíng)對(duì)不同林齡人工油松林水源涵養(yǎng)能力的影響[J].內(nèi)蒙古林業(yè)調(diào)查設(shè)計(jì),2017,40(5):6-9.
ZHAO B, LUO Y Y, WANG S S, et al. Effects of close-to-nature management on water conservation capacity of the artificial Pinus tabulaeformis forest of different ages[J]. Inner Mongolia Forestry Investigation and Design, 2017, 40(5): 6-9.
[9]賽克,高廣磊,于明含,等.不同經(jīng)營(yíng)方式對(duì)華北落葉松人工林林下生態(tài)特征的影響[J].河北農(nóng)業(yè)大學(xué)學(xué)報(bào),2016,39(5):37-43.
SAI K, GAO G L, YU M H, et al. Effects of different management on understory ecological characteristics of Larix principis-rupprechtii plantations[J]. Journal of Agricultural University of Hebei, 2016, 39(5): 37-43.
[10]許小明,鄒亞?wèn)|,孫景梅,等.黃土高原北洛河流域林地枯落物特征及水分吸持效應(yīng)[J].生態(tài)學(xué)報(bào),2021,41(13):5153-5165.
XU X M, ZOU Y D, SUN J M, et al. Litter characteristics and water retention capacity in major forestland in the Beiluo River Basin of the Loess Plateau[J]. Acta Ecologica Sinica, 2021, 41(13): 5153-5165.
[11]喻陽(yáng)華,李光容,皮發(fā)劍,等.赤水河上游主要森林類型水源涵養(yǎng)功能評(píng)價(jià)[J].水土保持學(xué)報(bào),2015,29(2):150-156.
YU Y H, LI G R, PI F J, et al. Water conservation function evaluation of some main forest type in the upper reaches of Chishui River[J]. Journal of Soil and Water Conservation, 2015, 29(2): 150-156.
[12]楊良辰,張春茹.沿壩地區(qū)3種典型林分類型枯落物層與土壤層水源涵養(yǎng)能力綜合評(píng)價(jià)[J].水土保持研究,2018,25(6):177-182.
YANG L C, ZHANG C R. Comprehensive evaluation of water conservation capacity in litter and soil layer of three typical forest types along the highland area[J]. Research of Soil and Water Conservation, 2018, 25(6): 177-182.
[13]趙鵬,馬佳明,李艷茹,等.太行山典型區(qū)域不同林分類型枯落物水文效應(yīng)[J].水土保持學(xué)報(bào),2020,34(5):176-185.
ZHAO P, MA J M, LI Y R, et al. Hydrological effects of litter in different forest types in the typical areas of Taihang Mountains[J]. Journal of Soil and Water Conservation, 2020, 34(5): 176-185.
[14]梁文俊,魏曦,趙偉文,等.關(guān)帝山不同林分結(jié)構(gòu)華北落葉松林枯落物水文效應(yīng)[J].水土保持學(xué)報(bào),2021,35(2):324-329,337.
LIANG W J, WEI X, ZHAO W W, et al. Hydrological effects of litter under different forest structures of Larix principis in Guandi Mountain[J]. Journal of Soil and Water Conservation, 2021, 35(2): 324-329, 337.
[15]杜雪,王海燕,耿琦,等.云冷杉針闊混交林枯落物持水性能[J].水土保持學(xué)報(bào),2021,35(2):361-368.
DU X, WANG H Y, GENG Q, et al. Water holding capacity of litter in spruce-fir coniferous and broad-leaved mixed forest[J]. Journal of Soil and Water Conservation, 2021, 35(2): 361-368.
[16]劉忠玲,劉建明,胡偉,等.不同密度胡桃楸次生林枯落物和土壤持水特性的研究[J].森林工程,2021,37(3):52-59,66.
LIU Z L, LIU J M, HU W, et al. Water-holding characteristics of litter and soil of Juglans mandshurica natural secondary forest with different densities[J]. Forest Engineering, 2021, 37(3): 52-59, 66.
[17]何琴飛,鄭威,彭玉華,等.珠江流域中游主要森林類型凋落物持水特性[J].水土保持研究,2017,24(1):128-134.
HE Q F, ZHENG W, PENG Y H, et al. Water-holding characteristics of litter under main forest types in the middle reaches of Pearl River Basin[J]. Research of Soil and Water Conservation, 2017, 24(1): 128-134.
[18]陳超凡,覃林,段藝璇,等.不同經(jīng)營(yíng)模式對(duì)蒙古櫟次生林葉功能性狀和土壤理化性質(zhì)的影響[J].生態(tài)學(xué)報(bào),2018,38(23):8371-8382.
CHEN C F, QIN L, DUAN Y X, et al. Effects of different management models on leaf functional traits and soil physical and chemical properties of natural secondary forest of Quercus mongolica[J]. Acta Ecologica Sinica, 2018, 38(23): 8371-8382.
[19]楊霞,陳麗華,康影麗,等.遼東低山區(qū)5種典型水源涵養(yǎng)林枯落物持水特性[J].生態(tài)學(xué)雜志,2019,38(9):2662-2670.
YANG X, CHEN L H, KANG Y L, et al. Water-holding characteristics of litter in five typical water conservation forests in low mountainous areas of eastern Liaoning[J]. Chinese Journal of Ecology, 2019, 38(9): 2662-2670.
[20]劉凱,賀康寧,王先棒.青海高寒區(qū)不同密度白樺林枯落物水文效應(yīng)[J].北京林業(yè)大學(xué)學(xué)報(bào),2018,40(1):89-97.
LIU K, HE K N, WANG X B. Hydrological effects of litter of Betula platyphylla forest with different densities in alpine region, Qinghai of northwestern China[J]. Journal of Beijing Forestry University, 2018, 40(1): 89-97.
[21]程唱,賀康寧,俞國(guó)峰,等.干旱半干旱區(qū)不同林型人工林水源涵養(yǎng)能力比較研究[J].生態(tài)學(xué)報(bào),2021,41(5):1979-1990.
CHENG C, HE K N, YU G F, et al. Comparative study on water conservation capacity of different forest types of artificial forest in arid and semi-arid area[J]. Acta Ecologica Sinica, 2021, 41(5): 1979-1990.
[22]董輝,嚴(yán)朝東,蘇純蘭,等.東莞5種生態(tài)公益林枯落物及土壤水文效應(yīng)[J].水土保持學(xué)報(bào),2021,35(5):144-149,160.
DONG H, YAN C D, SU C L, et al. Litter and soil hydrological effects of five no-commercial forests in Dongguan[J]. Journal of Soil and Water Conservation, 2021, 35(5): 144-149, 160.
[23]趙凱歌,周正虎,金鷹,等.長(zhǎng)期氮添加對(duì)落葉松和水曲柳人工林土壤碳、氮、磷含量和胞外酶活性的影響[J].南京林業(yè)大學(xué)學(xué)報(bào)(自然科學(xué)版),2022,46(5):177-184.
ZHAO K G, ZHOU Z H, JIN Y, et al. Effects of long-term nitrogen addition on soil carbon, nitrogen, phosphorus and extracellular enzymes in Larix gmelinii and Fraxinus mandshurica plantations[J].Journal of Nanjing Forestry University (Natural Science Edition), 2022, 46(5): 177-184.
[24]秦文靜,李小英,許彥紅,等.滇中地區(qū)典型公益林林分土壤養(yǎng)分及肥力研究[J].西部林業(yè)科學(xué),2022,51(2):145-154.
QIN W J, LI X Y, XU Y H, et al. Soil nutrients and fertility of typical public welfare forest in central Yunnan[J]. Journal of West China Forestry Science, 2022, 51(2): 145-154.
[25]孫擁康,湯景明,王怡.亞熱帶日本落葉松人工林枯落物及土壤層水文效應(yīng)[J].北京林業(yè)大學(xué)學(xué)報(bào),2021,43(8):60-69.
SUN Y K, TANG J M, WANG Y. Hydrological effects of litter and soil layers of Larix kaempferi plantation in subtropical regions[J]. Journal of Beijing Forestry University, 2021, 43(8): 60-69.
[26]彭玉華,鄭威,譚長(zhǎng)強(qiáng),等.廣西壯族自治區(qū)的臺(tái)灣榿木混交造林水源涵養(yǎng)功能評(píng)價(jià)[J].水土保持通報(bào),2019,39(5):98-105,112.
PENG Y H, ZHENG W, TAN C Q, et al. Evaluation of water conservation function of Alnus formosana mixed plantations in Guangxi Zhuang Autonomous Region[J]. Bulletin of Soil and Water Conservation, 2019, 39(5): 98-105, 112.
[27]王盛琦,傅文慧,寇建村,等.黃土高原水蝕風(fēng)蝕交錯(cuò)區(qū)沙地枯落物的水源涵養(yǎng)功能[J].水土保持通報(bào),2021,41(5):30-37.
WANG S Q, FU W H, KOU J C, et al. Water conservation capacity of litters on sandy land in wind-water erosion crisscross region of Loess Plateau[J]. Bulletin of Soil and Water Conservation, 2021, 41(5): 30-37.