选取新疆南部阿克苏市郊柯柯牙防护林不同林龄新疆杨(Populus alba var.pyramidalis)林下土壤为研究对象,以裸露地为对照,通过野外采样和室内分析,基于分形维数模型研究了不同种植年限新疆杨土壤颗粒分形维数(D)特征及其主要影响因素。...选取新疆南部阿克苏市郊柯柯牙防护林不同林龄新疆杨(Populus alba var.pyramidalis)林下土壤为研究对象,以裸露地为对照,通过野外采样和室内分析,基于分形维数模型研究了不同种植年限新疆杨土壤颗粒分形维数(D)特征及其主要影响因素。结果表明:不同年限新疆杨土壤D值处于2.2693~2.7104之间,明显高于裸露地(D=2.0545)(P<0.05),由高到低依次为22年生>15年生>6年生;在土壤深度10~30 cm和30~50 cm时,22年生防护林地D值较大,其它年龄林地各土层D值变化幅度不明显(P>0.05)。该防护林内各养分含量均高于裸露地,其差异显著(P<0.05),随杨树年龄的增长而增加。林地内土壤可溶性盐总量比裸露地降低了73%,其差异显著(P<0.05),随着杨树年龄的增长,土壤pH值及水溶性盐总量趋于降低。土壤颗粒分形维数与粉黏粒、土壤有机质、速效钾、全氮、有效磷、碱解氮、HCO_3^-等土壤理化参数呈显著正相关关系,与粗砂粒、Ca^(2+)、Mg^(2+)、SO_4^(2-)、Cl^-、K^++Na^+等呈显著负相关,与全磷和pH值相关性不大(P>0.05)。研究表明,柯柯牙人工防护林水土保持措施对土壤改良效益显著,随着种植年限的延长其效果越来越明显。展开更多
There are many different and even controversial results concerning the effects of Tamarisk on the physicochemical properties of soil. A year-round monitoring of soil salinity, p H and moisture is conducted beneath the...There are many different and even controversial results concerning the effects of Tamarisk on the physicochemical properties of soil. A year-round monitoring of soil salinity, p H and moisture is conducted beneath the Tamarisk shrub in a coastal wetland in the Bohai Sea in China, to ascertain the effects of Tamarisk on the physicochemical properties of soil in coastal wetland. Compared with the control area, the soil moisture content is lower around the area of the taproot when there is less precipitation in the growing season because of water consumption by Tamarisk shrub. However, the soil moisture content is higher around the taproot when there is more precipitation in the growing season or in the non-growing period because of water conservation by the rhizosphere. The absorption of salt by the Tamarisk shrub reduces the soil salinity temporarily, but eventually salt returns to the soil by the leaching of salt on leaves by rainfall or by fallen leaves. The annual average soil moisture content beneath the Tamarisk shrub is lower than the control area by only 6.4%, indicating that the Tamarisk shrub has little effect on drought or water conservation in soils in the temperate coastal wetland with moderate annual precipitation. The annual average salinity beneath the Tamarisk shrub is 18% greater than that of the control area, indicating that Tamarisk does have an effect of rising soil salinity around Tamarisk shrubs. The soil p H value is as low as 7.3 in summer and as high as 10.2 in winter. The p H of soil near the taproot of the Tamarisk shrubs is one p H unit lower than that in the control area during the growing season. The difference in p H is less different from the control area in the non-growing season, indicating that the Tamarisk shrub does have the effect of reducing the alkalinity of soil in coastal wetland.展开更多
文摘选取新疆南部阿克苏市郊柯柯牙防护林不同林龄新疆杨(Populus alba var.pyramidalis)林下土壤为研究对象,以裸露地为对照,通过野外采样和室内分析,基于分形维数模型研究了不同种植年限新疆杨土壤颗粒分形维数(D)特征及其主要影响因素。结果表明:不同年限新疆杨土壤D值处于2.2693~2.7104之间,明显高于裸露地(D=2.0545)(P<0.05),由高到低依次为22年生>15年生>6年生;在土壤深度10~30 cm和30~50 cm时,22年生防护林地D值较大,其它年龄林地各土层D值变化幅度不明显(P>0.05)。该防护林内各养分含量均高于裸露地,其差异显著(P<0.05),随杨树年龄的增长而增加。林地内土壤可溶性盐总量比裸露地降低了73%,其差异显著(P<0.05),随着杨树年龄的增长,土壤pH值及水溶性盐总量趋于降低。土壤颗粒分形维数与粉黏粒、土壤有机质、速效钾、全氮、有效磷、碱解氮、HCO_3^-等土壤理化参数呈显著正相关关系,与粗砂粒、Ca^(2+)、Mg^(2+)、SO_4^(2-)、Cl^-、K^++Na^+等呈显著负相关,与全磷和pH值相关性不大(P>0.05)。研究表明,柯柯牙人工防护林水土保持措施对土壤改良效益显著,随着种植年限的延长其效果越来越明显。
基金The Public Science and Technology Research Funds Projects of Ocean under contract No.201205008
文摘There are many different and even controversial results concerning the effects of Tamarisk on the physicochemical properties of soil. A year-round monitoring of soil salinity, p H and moisture is conducted beneath the Tamarisk shrub in a coastal wetland in the Bohai Sea in China, to ascertain the effects of Tamarisk on the physicochemical properties of soil in coastal wetland. Compared with the control area, the soil moisture content is lower around the area of the taproot when there is less precipitation in the growing season because of water consumption by Tamarisk shrub. However, the soil moisture content is higher around the taproot when there is more precipitation in the growing season or in the non-growing period because of water conservation by the rhizosphere. The absorption of salt by the Tamarisk shrub reduces the soil salinity temporarily, but eventually salt returns to the soil by the leaching of salt on leaves by rainfall or by fallen leaves. The annual average soil moisture content beneath the Tamarisk shrub is lower than the control area by only 6.4%, indicating that the Tamarisk shrub has little effect on drought or water conservation in soils in the temperate coastal wetland with moderate annual precipitation. The annual average salinity beneath the Tamarisk shrub is 18% greater than that of the control area, indicating that Tamarisk does have an effect of rising soil salinity around Tamarisk shrubs. The soil p H value is as low as 7.3 in summer and as high as 10.2 in winter. The p H of soil near the taproot of the Tamarisk shrubs is one p H unit lower than that in the control area during the growing season. The difference in p H is less different from the control area in the non-growing season, indicating that the Tamarisk shrub does have the effect of reducing the alkalinity of soil in coastal wetland.
