Study On Ecological And Economic Benefit And Adaption Of Herbage Planting In Yellow River Floodplian

Wind erosion and desertification is fierce in Yellow River Floodplian, Controling the expansion of wind-drift sand, improving ecological environment, developing farming and animal husbandry economics are always the urgent solution problems in this area. Herbage planting experimental adaptation was studied in Chiping wind-sand region of Yellow River in this paper, by the methods of random district experiment, field observation and laboratory experiment. 10 herbage species were introduced that include Sorghum Hybrid Sudangrass,Bromus intermis,Lolium perenne,Dactylis glomerata,Festuca arundinacea,Medicago satira L. cv.,Millionaire,Varnal,WL323 and Melilotus Albus. And the growth characteristic, Eco-efficiency ,economic benefits and eco-physiological characteristics of herbages were mainly studied in this thesis, while a comprehensive evaluation obtained by Analytic Hierarchy Process(AHP). The results show that:1,Studied herbages emerged orderly. the rate of emergence was 100%,and the rate of regeneration was also 100%. All of them can adapt to the growth environment of sandy area of Yellow River.2,The plant height and growth rate are different from the renewable speed after mowing and the growth rate after turning green to the first mowing. The height and biomass between different herbages have a Significant difference, before the first mowing. The height and biomass of Sorghum Hybrid Sudangrass were the highest(78.92cm), and the lowest was Melilotus suaveolens ledeb(30.84cm); The growth rate of Sorghum Hybrid Sudangrass is fastest(3.76cm/d), the slowest one is Melilotus suaveolens ledeb(0.91cm/d); After the first mowing, the renewable speed of Sorghum Hybrid Sudangrass is the fastest(3.76cm/d),the slowest one is Melilotus suaveolens ledeb(0.91cm/d).The renewable speed of other herbages are between 1.34cm/d and2.31cm/d. After turning green to the first mowing, the fastest growing herbage is Festuca arundinacea, that is 1.57cm/d. The slowest one is Bromus intermis leyss., that is 0.80cm/d.3,The root longth of different herbages have a significant difference, before the first mowing.To all herbages, the ratio of root and stem is less than 1. The average roots of Millionaire is the longest(27.25cm), and the shortest one is Bromus intermis leyss.(16.94cm). the ratio of root and stem of Millionaire is the largest(0.64), and the smallest one is Sorghum Hybrid Sudangrass(0.24).4,The production,the ratio of dry matter to fresh matter,the ratio of stem and leaves and the number of roots for the herbages are different from each other. The heaviest single plant biomass of fresh weight and dry matter is Sorghum Hybrid Sudangrass. The fresh weight of Melilotus suaveolens ledeb is lightest, and Dactylis glomerata has the lightest dry matter; The ratio of dry matter to fresh matter of Melilotus suaveolens ledeb is the highest(0.33), there is similar ratio of dry matter to fresh matter in other herbages, about 0.26; the ratio of dry stem and leaves of Sorghum Hybrid Sudangrass is the largest(1.07), and the smallest one is Melilotus suaveolens ledeb. Others are between 0.47 and 0.68. The order of the dry production per area from high to low is Sorghum Hybrid Sudangrass>Lolium perenne>Millionaire>Bromus intermis leyss.>Melilotus suaveolens ledeb>WL323>Medicago satira L. cv.>Varnal>Festuca arundinacea>Dactylis glomerata;The root system of herbages mainly distribute in the 0~30cm soil layer, and the total root quantity of leguminous herbage is more than the gramineae herbage generally. The level of distribution and vertical root distribution of different herbages have obviouse differences, which shows different capacity of soil and water-holding.5,The daily changes of net photosynthetic rate for the herbages are all bimodal curves. While the daily changes of transpiration rate displays unimodal curve. Different herbages have different performances of net photosynthetic rate and transpiration rate; The average daily WUE of the herbages from large to small is Sorghum Hybrid Sudangrass>Bromus intermis leyss. > Festuca arundinacea > Lolium perenne > Millionaire >Varnal > WL323 > Dactylis glomerata > Melilotus suaveolens ledeb >Medicago satira L. cv..6,Herbages have a significant effect on improving soil,control wind erosion,improving the micro-climate. The maximum water-holding rate is Dactylis glomerata, that is 430.97%. The minimum is Sorghum Hybrid Sudangrass, that is 173.57%. In ten herbages planting lands, the soil bulk density decreased 6.90%～16.55% and 4.79%～11.64% lower than control in 0～20cm and 20～40cm soil layers, The status of total porosity,capillay porosity and the non-capillary are superior to the control. The smaller than the 0.05mm side extremely fine sand content in herbage planting lands is 8.33～13.79% higher than that in wasteland. corrosion resistance pellet in soil increase, The composition of bigger than the 0.25mm side coarse sand content has dropped to 53.3～76.85% of wasteland,and erodibility physical pellet in soil decreased. The content of soil organic matter, alkali nitrogen, available phosphorus, available potassium in studied herbage land is higher than that in wasteland. That is 14.29% to 126.53%,22.72% to 376.15%,12.47% to 364.09% and 17.78% to 114.79%, respectively. Compared to the wind speed in 2m height, in 0.2m height in studied herbage decrease by 61.17% to 69.87%,the control decrease only 19.17%. Wind erosion reduction is more obvious in herbage planting land than that in wasteland, about 73.64% to 83.33% in spring. Herbages can make the soil temperature reduce 4℃to 9.5℃in 5cm to 20cm soil layers, respectively. Herbage has the effect on humidification obviously. The value is 3.6% to 5.7% of the control.7,The cost-effect and financial profitability of Sorghum Hybrid Sudangrass are highest up to 9.96and 8.96,compared with the lowest, Dactylis glomerata, that is 2.61 and 1.61. 8,The quality synthetic evaluation to herbage ordered from high to low is Sorghum Hybrid Sudangrass,Millionaire,Lolium perenne,Melilotus Albus,WL323,Bromus intermis,Medicago satira L. cv.,Varnal,Festuca arundinacea and Dactylis glomerata. The sequence can be used as a recommended order in planting herbage of sandy area of Yellow River.