【摘 要】
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Plantations have been widely established to improve ecosystem services and functioning.Black locust,Robinia pseudoacacia L.is a common,widely planted spe-cies to control soil erosion on the Loess Plateau.Previous studies have focused on economic values bu
【机 构】
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College of Resources and Environment,Huazhong Agricultural University,Wuhan 430070,People’s Republic
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Plantations have been widely established to improve ecosystem services and functioning.Black locust,Robinia pseudoacacia L.is a common,widely planted spe-cies to control soil erosion on the Loess Plateau.Previous studies have focused on economic values but the interac-tions between soil and plant carbon(C),nitrogen(N)and phosphorus(P)remain unknown.Investigating variations of soil,green and senesced leaf C,N and P levels in R.pseu-doacacia along a latitudinal gradient is useful to understand-ing its ecological functions.The results show that soil C,N and senesced leaf N and P significantly decreased with an increase in latitude,but there were no significant changes in the senesced leaf C and soil P.The resorption efficiency of N was related with latitude and soil N levels,and the rela-tion between green leaf N and soil N was significant.These relations suggest that soil N was the key in affecting green leaf N levels.At higher latitudes,senesced leaves had lower N levels associated with higher N resorption efficiency to maintain a stable N content in green leaves.With a decrease of soil N,R.pseudoacacia can enhance N resorption effi-ciency to meet the demand of growth.Thus,it is an impor-tant species for reforestation,especially in nutrient-poor environments.
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