草业科学
草業科學
초업과학
Pratacultural Science
2015年
10期
99-107
,共9页
谌芸%何丙辉%练彩霞%刘志鹏
諶蕓%何丙輝%練綵霞%劉誌鵬
심예%하병휘%련채하%류지붕
水土保持%根重密度%根长密度%根表面积密度%土壤养分
水土保持%根重密度%根長密度%根錶麵積密度%土壤養分
수토보지%근중밀도%근장밀도%근표면적밀도%토양양분
soil and water conservation%RWD (root weight density)%RLD (root length density)%RAD (root surface area density)%soil nutrient
为探讨紫色土区草本植物根系的改土培肥效应，选取已种植3年（2011－2013年）的水土保持常用草类紫花苜蓿、狗牙根和香根草为目标物种，分0～10 cm，10～20 cm，20～30 cm 土层采集根系和土壤样品，WinRHIZO （Pro．2004c）根系分析系统测定根系指标，常规方法测定土壤理化性质。结果表明：所有土层，香根草的各项根系指标均较优，尤其是根长密度和根表面积密度（最大均值分别为13．46 cm／cm3和5．75 cm2／cm3），紫花苜蓿则总体上的根重密度最好（最小均值为18．10 mg／cm3）；定植3年，这3种草本植物并未对试验区紫色土的机械组成产生显著影响，但在数值上草本区有粗颗粒减少、细颗粒增多的趋势；多数草本植物对多个土层的土壤有机质和速效钾产生显著影响（有机质增加，速效钾亏损），而对土壤全氮、碱解氮、总磷、有效磷和全钾的影响却很微弱；所有草本区的全钾含量较高3．93～4．83 g／kg，却在几乎所有土层出现速效钾的亏损，尤其是紫花苜蓿区最大亏损量达20．24 mg／kg；相关分析中，所有土壤养分与全部或部分根系指标呈现显著或极显著相关（最大相关系数为0．833）。
為探討紫色土區草本植物根繫的改土培肥效應，選取已種植3年（2011－2013年）的水土保持常用草類紫花苜蓿、狗牙根和香根草為目標物種，分0～10 cm，10～20 cm，20～30 cm 土層採集根繫和土壤樣品，WinRHIZO （Pro．2004c）根繫分析繫統測定根繫指標，常規方法測定土壤理化性質。結果錶明：所有土層，香根草的各項根繫指標均較優，尤其是根長密度和根錶麵積密度（最大均值分彆為13．46 cm／cm3和5．75 cm2／cm3），紫花苜蓿則總體上的根重密度最好（最小均值為18．10 mg／cm3）；定植3年，這3種草本植物併未對試驗區紫色土的機械組成產生顯著影響，但在數值上草本區有粗顆粒減少、細顆粒增多的趨勢；多數草本植物對多箇土層的土壤有機質和速效鉀產生顯著影響（有機質增加，速效鉀虧損），而對土壤全氮、堿解氮、總燐、有效燐和全鉀的影響卻很微弱；所有草本區的全鉀含量較高3．93～4．83 g／kg，卻在幾乎所有土層齣現速效鉀的虧損，尤其是紫花苜蓿區最大虧損量達20．24 mg／kg；相關分析中，所有土壤養分與全部或部分根繫指標呈現顯著或極顯著相關（最大相關繫數為0．833）。
위탐토자색토구초본식물근계적개토배비효응，선취이충식3년（2011－2013년）적수토보지상용초류자화목숙、구아근화향근초위목표물충，분0～10 cm，10～20 cm，20～30 cm 토층채집근계화토양양품，WinRHIZO （Pro．2004c）근계분석계통측정근계지표，상규방법측정토양이화성질。결과표명：소유토층，향근초적각항근계지표균교우，우기시근장밀도화근표면적밀도（최대균치분별위13．46 cm／cm3화5．75 cm2／cm3），자화목숙칙총체상적근중밀도최호（최소균치위18．10 mg／cm3）；정식3년，저3충초본식물병미대시험구자색토적궤계조성산생현저영향，단재수치상초본구유조과립감소、세과립증다적추세；다수초본식물대다개토층적토양유궤질화속효갑산생현저영향（유궤질증가，속효갑우손），이대토양전담、감해담、총린、유효린화전갑적영향각흔미약；소유초본구적전갑함량교고3．93～4．83 g／kg，각재궤호소유토층출현속효갑적우손，우기시자화목숙구최대우손량체20．24 mg／kg；상관분석중，소유토양양분여전부혹부분근계지표정현현저혹겁현저상관（최대상관계수위0．833）。
In order to explore the effects of herb roots on soil physical properties and soil nutrients,alfalfa (Medicago sativa ),Bermuda grass (Cynodon dactylon )and vetiver grass (Vetiveria zizanioides ),planted for three years,were used for these experiments.Taking bare plots as a contrast,soil and root samples from 0-10 cm,10-20 cm and 20-30 cm soil layers were collected.Then the WinRHIZO (Pro.2004c)root analy-sis system was used to measure root parameters and conventional methods were used to measure soil physical and chemical properties.In all three soil layers,vetiver grass root parameters were excellent,especially root length density and root surface area density,for these two traits the maxima averaged 13.46 cm/cm3 and 5.75 cm2/cm3 ,respectively.Overall,root weight density (RWD)of alfalfa was the greatest,with a minimum aver-age of 18.10 mg/cm3 .None of the three herbs had any significant effects on soil physical properties 3 years af-ter planting,but data for the herb plots showed that the proportion of sand particles had decreased and the pro-portion of finer particles (silt and clay)had increased,compared to bare CK plots.Most herbs had significant effects on soil organic matter and available potassium in most soil layers,with content of organic matter in-creasing and content of available potassium decreasing.However,the herbs had almost no effect on soil total nitrogen,alkali-hydrolyzable nitrogen,total phosphorous,available phosphorous and total potassium.The to-tal potassium contents of all herb plots (3.93-4.83 g/kg)were higher than the bare plots,but the available potassium levels of all herb plots were low,especially in alfalfa.The maximum deficient number was 20.24 mg/kg.All soil nutrients had significant correlations (P <0.05)with all or some of the root parameters,and the maximum correlation coefficient was 0.833,for the relationship between organic matter and RWD.
