花椒林—牧草间作对牧草生长、光合特性及土壤理化性质的影响
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摘要
环境日益受到人们的重视,可持续发展逐渐成为人们所追求的目标。在退耕还林还草,进行生态建设和改造中,其核心应该是应用生态系统管理的思想对社会、经济和自然系统进行合理调控以实现区域社会——经济——自然复合生态系统的高效、和谐可持续发展。长期以来林业以展一直受到经营单一化的制约,效益不高,单位面积的土地生产力低下,林业的可持续发展受到严重影响。林草复合经营在解决区域农林争地矛盾、挖掘生物资源潜力,协调资源合理利用、保护改善生态环境、促进粮食增产等方面发挥着日益重要的作用和效益。而且甘肃临夏州是一个人多地少、土壤贫瘠、主要以生态林和经济林为主的干旱、半干旱地区,因此探索甘肃临夏地区的林草复合种植模式具有较深远的意义。
本研究是在国家林业局科技成果转化项目——“天保”工程林间红豆草—紫花苜蓿等优良牧草推广种植项目的基础上,结合“十一五”国家科技支撑项目“奶业优质饲草生产技术研究开发”中的“西北地区高效林草间作模式与技术体系研究”子子课题,在甘肃临夏州进行花椒林——牧草的林草间作研究。试验主要选取9年生花椒林和紫花苜蓿、白三叶、百脉根、小麦作为研究对象,应用生理学和生态经济学的原理和方法,对三种林草间作模式的生态效益和经济效益进行评价分析。结果表明:
(1)从间作物和花椒的物候期可以发现:小麦的物候期与花椒的物候期基本重叠,小麦的生长受到花椒树的遮荫影响严重。而间作牧草主要收获的是牧草产量,间作后,其营养生长期相对延长约半个月左右。在生长过程中,生长最快的是在5月中下旬,百脉根生长最快可达4.515cm/d,苜蓿达2.920cm/d。而小麦的第一个高生长期是在5月初,约2.74cm/d。
(2)三种豆科牧草的光合日变化曲线都呈双曲线,而且上午第一个峰值高于第二个峰值。第一个峰值三种牧草分别为:苜蓿10.89μmolCO_2m~(-2)s~(-1),百脉根8.94μmolCO_2m~(-2)s~(-1),白三叶5.13μmolCO_2m~(-2)s~(-1),而第二个峰值分别为:苜蓿4.10μmolCO_2m~(-2)s~(-1),百脉根4.45μmolCO_2m~(-2)s~(-1),白三叶4.64μmolCO_2m~(-2)s~(-1)。三种植物的光响应通过Dagneli的光响应曲线拟合效果较好,通过拟合,求得三种植物的光饱和点分别为:苜蓿2367μmolm~(-2)s~(-1),百脉根2198μmolm~(-2)s~(-1),白三叶1475μmolm~(-2)s~(-1);光补偿点分别为:苜蓿46.49μmolm~(-2)s~(-1),百脉根15.19μmolm~(-2)s~(-1),白三叶44.28μmolm~(-2)s~(-1);表观量子效率分别为:苜蓿0.065mol/mol~(-1),百脉根0.024mol/mol~(-1),白三叶0.098mol/mol~(-1)。
(3)在林地间作牧草可以提高土壤的水分含量,起到涵养水源的作用。就三种间作地的土壤水分含量,通过方差分析得出,在四个不同土壤深度种植苜蓿与未间作的花椒林其土壤水分都具有显著性差异,尤其是6cm和10cm其水土壤水分具有极显著性差异;间作百脉根和间作白三叶的各层与未间作的花椒林地其也具有一定的显著性差异。间作地其6cm,10cm,15cm,20cm土壤含水量比未间作地分别高出3.55%,3.02%,3.63%,3.38%。
(4)牧草的根系分布是反映固持土壤能力的一个指标,尤其是表层土壤根系的分布。就三种豆科牧草在林地间作中的根系分布情况为:0-5cm白三叶、百脉根、苜蓿和对照生物量(干重)分别为1595 Kg/hm2,1025.833 Kg/hm2,1113.3 Kg/hm2,100 Kg/hm2,分别占所测总生物量的67.73%、42.39%、42.24%和14.47%。其中0-5cm土壤中白三叶、百脉根和苜蓿的毛细根量分别为902.5 Kg/hm2,630 Kg/hm2,432.667 Kg/hm2。
(5)就三种林草间作模式的对土壤肥力变化的研究结果显示:由于豆科牧草,具有较强的自身固氮能力。就碱解氮的含量,间作牧草地比未间作地明显提高,苜蓿、百脉根和白三叶比未间作地分别高出约14.35mg/Kg、14.76mg/Kg和6.51mg/Kg。通过方差分析结果显示,间作苜蓿与百脉根与未间作地,其碱解氮的含量呈极显著性差异。
(6)以间作物的经济产量可得:苜蓿的年干产量最高,达549.72 Kg/667m~2,其次是白三叶约271.79 Kg/667m~2,百脉根的产量约252.16 Kg/667m~2。由二茬的产量结果显示,在第一茬苜蓿的鲜草产量最高,达1782.37 Kg/667m~2,而第二茬白三叶的鲜草产量比苜蓿高约68.18 Kg/667m~2,但干草产量仍为苜蓿最高105.65 Kg/667m~2。间作小麦与间作苜蓿、百脉根和白三叶相比其鲜产量分别低出约1181.83 Kg/667m~2,1374.02 Kg/667m~2和1700.85 Kg/667m~2,但干产量小麦要高于苜蓿约85.38 Kg/667m~2。
Peple now pay more and more attention to environment which are one of main problems the world is confronted with .Sustainabledevelopment comes to be an object people aim at .In order to achieve the effective ,harmonious and sustainable development of the local social-economic-natural compound ecosystem ,the core of ecological forestry construction should be regulationg the social ,economic and natural systems rationally in accord with the principle of the applicable ecosystem management .Long time ago ,single management has restricted the development of forest practice .Low benefit and soil productivity are the prominent characteristics ,so the sustainable development of forest is held back . Tree-grass complex has played an increasingly important role in the solution of local agro-forest confliction for land ,expoitation of biological resources ,balance of resource utilization ,environmental conservation ,improvement of food production ,and so on. At the same time ,linxia gansu province is arid and sem-iarid,and the soil is proven and less than what their need, ecological forestry and economic forestry play an impotent role in local. So finding new models to develop forest is meaningful.
This research was basted on“Tianbao”project——the generalization of forestry intercropping with alfalfa ,Onobrychis and other forages which is the project of state forestry Bureau scientific and technological payoffs transformation ,and according to the topic dairy high quality forage grass production engineering reseatch and development——northwestern highly effective tree-grass intercropping pattern and technical systern research which is the project of“shi yi wu”national science and technology support . Tish research is located in linxia gansu province ,baded on 9 years Chinese prickly ash intercropping with alfalfa ,white clover and bird's foot trefoil.We studied the ecological and economic efficiency using econology principle and method.
This paper summarizes the tree-grass complex system, the results show that :
(1) From the phenophase from the interplanting of plants and Chinese prickly ash,we may discover that :the phenophase of Wheat and Chinese prickly ash is overlap, so the wheat's growth is serious influenced by the Chinese prickly ash tree, but interplanting with forage grass main lengthens the nutrition vegetal period and harvest more grass. What grows is quickest in mid-May, the lotus corniculatus grows may reach the 4.515cm/d, and the alfalfa reaches the 2.920cm/d. But the wheat's first high vegetal period is at the beginning of May, approximately 2.74cm/d.
(2) The photosynthesis curve of three kind of leguminous forage is double peak type, moreover the morning first peak is higher than the second . The first peak of three pasturages respectively are: Alfalfa is 10.89μmolCO_2m~(-2)s~(-1), lotus corniculatus is 8.94μmolCO_2m~(-2)s~(-1), white clover is 5.13μmolCO_2m~(-2)s~(-1), but the second peak value respectively is: Alfalfa is 4.10μmolCO_2m~(-2)s~(-1), lotus corniculatus is 4.45μmolCO_2m~(-2)s~(-1), white clover is 4.64μmolCO_2m~(-2)s~(-1). Through the Dagneli light response curve fitting is good and obtains the light saturation points is: Alfalfa 2367μmolCO_2m~(-2)s~(-1), lotus corniculatus 2198μmolCO_2m~(-2)s~(-1), white three 1475μmolCO_2m~(-2)s~(-1); The light compensation point is: Alfalfa 40.49μmolCO_2m~(-2)s~(-1), lotus corniculatus 15.19μmolCO_2m~(-2)s~(-1), white three 44.28μmolCO_2m~(-2)s~(-1); The apparent quantum yield is: Alfalfa 0.065mol/mol~(-1), lotus corniculatus 0.024mol/mol~(-1), white three 0.098mol/mol~(-1).
(3) Tree-grass interplanting may enhance the soil moisture content,play an impotent role in self-control water source. Through variance analysis the soil moisture of interplanting show that: the soil moistrte of alfalfa interplanting with Chinese prickly ash has the significance difference in four different depth, particularly 6cm and 10cm also have the extremely significance difference; The interplanting with lotus corniculatus and white clover also has significance difference in different depth . The soil moisture of tree-grass complex is 3.55%, 3.02%, 3.63%, 3.38% higher than solid planting of trees on 6cm,10 cm,15cm,20 cm .
(4) The forage grass root system distribution is reflects the persisting soil ability, particularly the distribution of surface layer. The root system distributed situation is: In 0-5cm white clover , the lotus corniculatus, the alfalfa and the comparison (dry weight) is 1595Kg/hm2,1025.833Kg/hm2,1113.3 Kg/hm2, 100 Kg/hm2 ,occupies the total biomass 67.73%, 42.39%, 42.24% and 14.47%. In the 0-5cm soil white clover , the lotus corniculatus and alfalfa's capillarity root quantity respectively is 902.5 Kg/ hm2, 630Kg/ hm2, 432.667Kg/hm2.
(5) The soil fertility of three kind of tree-grass interplanting patternshow that : As a result of the strong own nitrogen-fixing capacity of leguminous forage. On the nitrogen's content, the intercropping with alfalfa, lotus corniculatus and white clover is 14.35 mg/Kg, 14.76 mg/Kg and 6.51 mg/Kg higher than not interplanting. The variance analysis result show that the interplanting with alfalfa and lotus corniculatus has extremely significance difference with unintercropping.
(6) The economic outputs of interplanting show that : Alfalfa's annual output is highest, reaches 549.72Kg/ 667m~2, next is white three , is 271.79 Kg/667m~2, lotus corniculatus's output is 252.16Kg/667m~2. The two harvest in one year show that alfalfa's fresh output is the highest in the first stubble,is reaches 1782.37Kg/667m~2, but the second stubble, white clover fresh grass output is 68.18Kg/667m~2 higher than alfalfa, but the alfalfa of hay output is still highest ,teaches 105.65Kg/667m~2. Interplanting of wheat the fresh output is 1181.83 Kg/667m~2,1374.02 Kg/667m~2 and 1700.85 Kg/667m~2 lower than alfalfa, lotus corniculatus and white clover .but the dry matter quantity of wheat is 85.38 Kg/667m~2 higher than the alfalfa.
本研究是在国家林业局科技成果转化项目——“天保”工程林间红豆草—紫花苜蓿等优良牧草推广种植项目的基础上,结合“十一五”国家科技支撑项目“奶业优质饲草生产技术研究开发”中的“西北地区高效林草间作模式与技术体系研究”子子课题,在甘肃临夏州进行花椒林——牧草的林草间作研究。试验主要选取9年生花椒林和紫花苜蓿、白三叶、百脉根、小麦作为研究对象,应用生理学和生态经济学的原理和方法,对三种林草间作模式的生态效益和经济效益进行评价分析。结果表明:
(1)从间作物和花椒的物候期可以发现:小麦的物候期与花椒的物候期基本重叠,小麦的生长受到花椒树的遮荫影响严重。而间作牧草主要收获的是牧草产量,间作后,其营养生长期相对延长约半个月左右。在生长过程中,生长最快的是在5月中下旬,百脉根生长最快可达4.515cm/d,苜蓿达2.920cm/d。而小麦的第一个高生长期是在5月初,约2.74cm/d。
(2)三种豆科牧草的光合日变化曲线都呈双曲线,而且上午第一个峰值高于第二个峰值。第一个峰值三种牧草分别为:苜蓿10.89μmolCO_2m~(-2)s~(-1),百脉根8.94μmolCO_2m~(-2)s~(-1),白三叶5.13μmolCO_2m~(-2)s~(-1),而第二个峰值分别为:苜蓿4.10μmolCO_2m~(-2)s~(-1),百脉根4.45μmolCO_2m~(-2)s~(-1),白三叶4.64μmolCO_2m~(-2)s~(-1)。三种植物的光响应通过Dagneli的光响应曲线拟合效果较好,通过拟合,求得三种植物的光饱和点分别为:苜蓿2367μmolm~(-2)s~(-1),百脉根2198μmolm~(-2)s~(-1),白三叶1475μmolm~(-2)s~(-1);光补偿点分别为:苜蓿46.49μmolm~(-2)s~(-1),百脉根15.19μmolm~(-2)s~(-1),白三叶44.28μmolm~(-2)s~(-1);表观量子效率分别为:苜蓿0.065mol/mol~(-1),百脉根0.024mol/mol~(-1),白三叶0.098mol/mol~(-1)。
(3)在林地间作牧草可以提高土壤的水分含量,起到涵养水源的作用。就三种间作地的土壤水分含量,通过方差分析得出,在四个不同土壤深度种植苜蓿与未间作的花椒林其土壤水分都具有显著性差异,尤其是6cm和10cm其水土壤水分具有极显著性差异;间作百脉根和间作白三叶的各层与未间作的花椒林地其也具有一定的显著性差异。间作地其6cm,10cm,15cm,20cm土壤含水量比未间作地分别高出3.55%,3.02%,3.63%,3.38%。
(4)牧草的根系分布是反映固持土壤能力的一个指标,尤其是表层土壤根系的分布。就三种豆科牧草在林地间作中的根系分布情况为:0-5cm白三叶、百脉根、苜蓿和对照生物量(干重)分别为1595 Kg/hm2,1025.833 Kg/hm2,1113.3 Kg/hm2,100 Kg/hm2,分别占所测总生物量的67.73%、42.39%、42.24%和14.47%。其中0-5cm土壤中白三叶、百脉根和苜蓿的毛细根量分别为902.5 Kg/hm2,630 Kg/hm2,432.667 Kg/hm2。
(5)就三种林草间作模式的对土壤肥力变化的研究结果显示:由于豆科牧草,具有较强的自身固氮能力。就碱解氮的含量,间作牧草地比未间作地明显提高,苜蓿、百脉根和白三叶比未间作地分别高出约14.35mg/Kg、14.76mg/Kg和6.51mg/Kg。通过方差分析结果显示,间作苜蓿与百脉根与未间作地,其碱解氮的含量呈极显著性差异。
(6)以间作物的经济产量可得:苜蓿的年干产量最高,达549.72 Kg/667m~2,其次是白三叶约271.79 Kg/667m~2,百脉根的产量约252.16 Kg/667m~2。由二茬的产量结果显示,在第一茬苜蓿的鲜草产量最高,达1782.37 Kg/667m~2,而第二茬白三叶的鲜草产量比苜蓿高约68.18 Kg/667m~2,但干草产量仍为苜蓿最高105.65 Kg/667m~2。间作小麦与间作苜蓿、百脉根和白三叶相比其鲜产量分别低出约1181.83 Kg/667m~2,1374.02 Kg/667m~2和1700.85 Kg/667m~2,但干产量小麦要高于苜蓿约85.38 Kg/667m~2。
Peple now pay more and more attention to environment which are one of main problems the world is confronted with .Sustainabledevelopment comes to be an object people aim at .In order to achieve the effective ,harmonious and sustainable development of the local social-economic-natural compound ecosystem ,the core of ecological forestry construction should be regulationg the social ,economic and natural systems rationally in accord with the principle of the applicable ecosystem management .Long time ago ,single management has restricted the development of forest practice .Low benefit and soil productivity are the prominent characteristics ,so the sustainable development of forest is held back . Tree-grass complex has played an increasingly important role in the solution of local agro-forest confliction for land ,expoitation of biological resources ,balance of resource utilization ,environmental conservation ,improvement of food production ,and so on. At the same time ,linxia gansu province is arid and sem-iarid,and the soil is proven and less than what their need, ecological forestry and economic forestry play an impotent role in local. So finding new models to develop forest is meaningful.
This research was basted on“Tianbao”project——the generalization of forestry intercropping with alfalfa ,Onobrychis and other forages which is the project of state forestry Bureau scientific and technological payoffs transformation ,and according to the topic dairy high quality forage grass production engineering reseatch and development——northwestern highly effective tree-grass intercropping pattern and technical systern research which is the project of“shi yi wu”national science and technology support . Tish research is located in linxia gansu province ,baded on 9 years Chinese prickly ash intercropping with alfalfa ,white clover and bird's foot trefoil.We studied the ecological and economic efficiency using econology principle and method.
This paper summarizes the tree-grass complex system, the results show that :
(1) From the phenophase from the interplanting of plants and Chinese prickly ash,we may discover that :the phenophase of Wheat and Chinese prickly ash is overlap, so the wheat's growth is serious influenced by the Chinese prickly ash tree, but interplanting with forage grass main lengthens the nutrition vegetal period and harvest more grass. What grows is quickest in mid-May, the lotus corniculatus grows may reach the 4.515cm/d, and the alfalfa reaches the 2.920cm/d. But the wheat's first high vegetal period is at the beginning of May, approximately 2.74cm/d.
(2) The photosynthesis curve of three kind of leguminous forage is double peak type, moreover the morning first peak is higher than the second . The first peak of three pasturages respectively are: Alfalfa is 10.89μmolCO_2m~(-2)s~(-1), lotus corniculatus is 8.94μmolCO_2m~(-2)s~(-1), white clover is 5.13μmolCO_2m~(-2)s~(-1), but the second peak value respectively is: Alfalfa is 4.10μmolCO_2m~(-2)s~(-1), lotus corniculatus is 4.45μmolCO_2m~(-2)s~(-1), white clover is 4.64μmolCO_2m~(-2)s~(-1). Through the Dagneli light response curve fitting is good and obtains the light saturation points is: Alfalfa 2367μmolCO_2m~(-2)s~(-1), lotus corniculatus 2198μmolCO_2m~(-2)s~(-1), white three 1475μmolCO_2m~(-2)s~(-1); The light compensation point is: Alfalfa 40.49μmolCO_2m~(-2)s~(-1), lotus corniculatus 15.19μmolCO_2m~(-2)s~(-1), white three 44.28μmolCO_2m~(-2)s~(-1); The apparent quantum yield is: Alfalfa 0.065mol/mol~(-1), lotus corniculatus 0.024mol/mol~(-1), white three 0.098mol/mol~(-1).
(3) Tree-grass interplanting may enhance the soil moisture content,play an impotent role in self-control water source. Through variance analysis the soil moisture of interplanting show that: the soil moistrte of alfalfa interplanting with Chinese prickly ash has the significance difference in four different depth, particularly 6cm and 10cm also have the extremely significance difference; The interplanting with lotus corniculatus and white clover also has significance difference in different depth . The soil moisture of tree-grass complex is 3.55%, 3.02%, 3.63%, 3.38% higher than solid planting of trees on 6cm,10 cm,15cm,20 cm .
(4) The forage grass root system distribution is reflects the persisting soil ability, particularly the distribution of surface layer. The root system distributed situation is: In 0-5cm white clover , the lotus corniculatus, the alfalfa and the comparison (dry weight) is 1595Kg/hm2,1025.833Kg/hm2,1113.3 Kg/hm2, 100 Kg/hm2 ,occupies the total biomass 67.73%, 42.39%, 42.24% and 14.47%. In the 0-5cm soil white clover , the lotus corniculatus and alfalfa's capillarity root quantity respectively is 902.5 Kg/ hm2, 630Kg/ hm2, 432.667Kg/hm2.
(5) The soil fertility of three kind of tree-grass interplanting patternshow that : As a result of the strong own nitrogen-fixing capacity of leguminous forage. On the nitrogen's content, the intercropping with alfalfa, lotus corniculatus and white clover is 14.35 mg/Kg, 14.76 mg/Kg and 6.51 mg/Kg higher than not interplanting. The variance analysis result show that the interplanting with alfalfa and lotus corniculatus has extremely significance difference with unintercropping.
(6) The economic outputs of interplanting show that : Alfalfa's annual output is highest, reaches 549.72Kg/ 667m~2, next is white three , is 271.79 Kg/667m~2, lotus corniculatus's output is 252.16Kg/667m~2. The two harvest in one year show that alfalfa's fresh output is the highest in the first stubble,is reaches 1782.37Kg/667m~2, but the second stubble, white clover fresh grass output is 68.18Kg/667m~2 higher than alfalfa, but the alfalfa of hay output is still highest ,teaches 105.65Kg/667m~2. Interplanting of wheat the fresh output is 1181.83 Kg/667m~2,1374.02 Kg/667m~2 and 1700.85 Kg/667m~2 lower than alfalfa, lotus corniculatus and white clover .but the dry matter quantity of wheat is 85.38 Kg/667m~2 higher than the alfalfa.
引文
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