摘要:在貴州普定縣后寨河小流域75km2面積內(nèi),采用150m×150m的網(wǎng)格布點(diǎn)方式,挖設(shè)2755個(gè)土壤剖面,研究了土壤厚度在小流域內(nèi)的分布及其影響因素,并對(duì)喀斯特小流域土壤概念進(jìn)行了探討,結(jié)果表明從流域尺度來(lái)看,當(dāng)前研究的熱點(diǎn)問(wèn)題中存在的一個(gè)新詞匯即喀斯特土壤,需要定義為由喀斯特巖石發(fā)育形成的土壤,而不應(yīng)該理解為分布在喀斯特區(qū)域內(nèi)的土壤,否則極易導(dǎo)致理解差異而形成誤解。流域尺度下土壤的分布特征表現(xiàn)為8度以下坡度條件下多分布厚度大的土層,而隨著坡度的增加土層厚度減小;喀斯特與非喀斯特的土壤厚度存在差別,海拔條件下的土壤厚度與地貌特征關(guān)聯(lián)度較大;而人為作用則由于主動(dòng)選擇的結(jié)果,人為影響大的土壤厚度較大;小流域內(nèi)土壤厚度的影響因素主要與水動(dòng)力條件相關(guān),表現(xiàn)在坡度、坡位的主要影響方面,因此小流域土壤的利用需要考慮到土壤厚度的分布特征,即土壤厚度大的區(qū)域可以進(jìn)行利用,但土層薄的區(qū)域則需要加強(qiáng)保護(hù),尤其是坡度較大的區(qū)域;而石漠化區(qū)域則需要進(jìn)行治理并加強(qiáng)保護(hù)。
關(guān)鍵詞:喀斯特小流域; 喀斯特土壤;土壤厚度;分布特征;利用與保護(hù)
中圖分類(lèi)號(hào):S1522
文獻(xiàn)標(biāo)識(shí)碼:A
文章編號(hào):1008-0457(2017)03-0001-05國(guó)際DOI編碼:10.15958/j.cnki.sdnyswxb.2017.03.001
Abstract:2755 profiles were dug according grid of 150m×150m 75km2 area of small watershed of Houzhaihe,Puding,Guizhou provinceInfluencing factors of soil thickness distribution were studied,and the concept of karst soil was discussed,the results showed as follow,currently,karst soil,a new word of extremely used,is difficult to understand for the meanings’ confusion,which needed to be defined exactly to be developed from the karst rocks and to be distinguished from the soil distributed in karst areaSoil was thicker when slope was lower than 8 degree,but thinner as the slope increasedThe thickness of karst soil thinner than non-karst soil,soil thickness was increased with the decrease of altitude about sea level in the small watershedSoil was thicker owing to the selection of humanFrom about,soil thickness was controlled by hydrodynamic force such as degree of slope and position of slopeIt is needed to consider soil thickness while utilizing of soil in the small watershed,which means soil can be used while soil thickness is larger,but need to be protected while soil thickness is thinner,especially area of larger slope degreeThe area of karst rocky desertification is needed to be managed and strengthened protection
Key words:karst small watershed;karst soils;soil thickness;distributional characteristics;utilization and protection
喀斯特地區(qū)由于特殊的二元水文結(jié)構(gòu)以及復(fù)雜的峰叢、峰林、洼地和漏斗等地貌形態(tài),成土速率慢,土層淺薄且不連續(xù)[1]。受成土母質(zhì)地形氣候植被等成土因素及人為干擾活動(dòng)影響,喀斯特土壤具有復(fù)雜性和高度的空間變異性 [2,3]。……