Contrast And Analysis On Transpiration Water Consumption Between Plantation Community And Desert Shrub Community In Arid Region

For contrasting and analysis the transpiration water consumption between plantation commynity and desert shrub community in Arid Region, Flow4-DL and Prober12 were used to measure P.alba,P.xrusskii, Haloxylon ammodendron,Tamarix elongate sap-flow dynamics and the envirement factors in Karamay Cabe forest and the outer margin during August, 30 , 2009– October, 30, 2010.The change characters of plantation tree and desert shrub sap flow and the method to caculate tree and shrub stands transpiration water consumption were contrasted and analysised. The cheif results were show as followed:(1). The sap flow of plantation tree and desert shrub change as a single-peak curve and came in being small-scope fluctuation at peak time. The scope of fluctuation at peak time bacame bigger with DBH or diameter of branch increased. The dyanamix curve of plantation sap flow was smoother than desert shrub's.(2).Solar radiation,PAR,wind speed,Air humidity were the main factor of plantation and desert shrub sap flow. The firstly domination factor of Haloxylon ammodendron,Tamarix elongate sap-flow was PAR and Wind speed second. The first and second domination factor of P.alba, P.xrusskii were respectivly Air humidity and PAR. Same main factors and a dominating factor can be used to fit the sap flow. The fittings result of the former was better than the later,but the later's fitting equetion was easy and efficient,so we select the domination factor to fit sap flow.(3). The sap flow of plantation and desert shrub would decreased in rainy day than in dry day. When the rain occurred during a day ,the sap flow would decreased and the range was small; when during a night, the sap flow would increased than dry night and the range was great. The plantation's sap flow would increased only when it was raining and one or two hours before and after the rain and decrease in whole rainy day. The desert shrub'sap flow would increased before raining in night and the flowing night of the rainy day. The change of Tamarix elongate'sap flow in rainy day was great than The change of Haloxylon ammodendron's.(4). The sap velocity and DBH / diameter of branch were significantly correlated and the relation between them could be use different functions to fit and have been determind. The relation between P.xrusskii sap velocity and DBH could fit with logarithmic function, P.alba was line function; The relation between Haloxylon ammodendron's sap velocity and diameter of branch could fit with exponential function, and Tamarix elongate's power function.(5). The fitting equation which fitted the relations of sap velocity and DBH / diameter of branch can compare the ability of different plant'transpiration water consumption. The ability of P.xrusskiil's transpiration water consumpution was higher than P.alba's , the drought resistant ability was lower than P.alba's and conversely P.xrusskii's transpirtion water consumption ability was lower and drought resistant ability was higher than P.alba's. Haloxylon ammodendron's transpiration water consumption abilty was lower than P.xrusskiil's and the drought resistant ability was higher when diameter of branch during 1cm - 3cm. P.alba's water-saving was bigger than P.xrusskiil's as a whole,becouse there were mainly plant whose DBH wre less 10cm.(6). It was advisable to use diameter and sapwood area as convert scalar to calculate plantation stands transpiration water consumption. There was a power regression equtation between P.xrusskiil and P.alba's sapwood area and DBH. The poplar plantation'transpiration water consumption was 30.84t/hm2d by This equtation and fitting equation which fitted the relations of sap velocity and DBH. The diameter of branch and crown of shurb could be used as convert scalar to caculate the desert shurb stands transpiration water consumption. There was a exponential regression equtation between Haloxylon ammodendron's transpiration water consumption and crown. The transpiration water consumption is 19.04 times as much as Haloxylon ammodendron's. The stands'transpiration water consumption of Karamy cabe forest was 1.62t/hm2d before the base builting up and 92451.54t/d now, recreased by 84433.72t/d. The cost of water was 2760.49yuan/d. It would taken 422.4 thousand Yuan in whole growing season becouse of the transpirantion water consumption.(7). The stands transpiration water consumption in poplar plantation varies with planting model,planting way and planting density, so there are the highest water use efficency in the same mageagement patten. The highest water use efficiency of P.alba's stands planting by the maneagement of single-channel and single-planting is 4.5m×2m with the water consumption 49.65t/hm2d. Then it is 4.5m×0.75m×0.5m in the maneagement patton of single-channel and double-planting with the water consumption 60.86t/hm2d, 8m×2m×2m in zoon planting with internal 8 maters with water consumption 8.39t/hm2d. In the same planting idensity ,the water consumption of single-channel and double-planting is highest,followed by single-channel and double-planting's, and that of zoon planting with internal 8 maters is lowest, and 48.06 t/hm2d,34.36 t/hm2d,24.88 t/hm2d respectively.