Dynamics of soil nitrogen availability following vegetation restoration along a climatic gradient of a subtropical karst region in China
Author(s)
Hu, Peilei
Zhao, Yuan
Xiao, Dan
Xu, Zhihong
Zhang, Wei
Xiao, Jun
Wang, Kelin
Griffith University Author(s)
Year published
2021
Metadata
Show full item recordAbstract
Purpose: Soil nitrogen (N) availability plays an important role in determining ecosystem structure and function. However, the variation patterns of soil N availability under different vegetation restoration strategies along climatic gradients in the ecologically fragile karst region of China have been poorly understood. Methods: Soil N variables, including total N (TN), inorganic N [ammonium (NH ) and nitrate (NO )], and rates of net N mineralization and nitrification were measured following managed (plantation forest) and natural (spontaneous regeneration) vegetation restoration along a climatic gradient in the karst region ...
View more >Purpose: Soil nitrogen (N) availability plays an important role in determining ecosystem structure and function. However, the variation patterns of soil N availability under different vegetation restoration strategies along climatic gradients in the ecologically fragile karst region of China have been poorly understood. Methods: Soil N variables, including total N (TN), inorganic N [ammonium (NH ) and nitrate (NO )], and rates of net N mineralization and nitrification were measured following managed (plantation forest) and natural (spontaneous regeneration) vegetation restoration along a climatic gradient in the karst region of southwestern China. Results: Compared to that in the cropland, soil TN and NH concentrations significantly increased in both vegetation restoration strategies after 15 years of cropland abandonment. The net N mineralization and nitrification rates were lower in both vegetation restoration strategies compared with those in cropland and secondary forest. There were no significant differences in the soil N variables between the two vegetation restoration strategies. Furthermore, soil NO was positively correlated with mean annual temperature (MAT) following vegetation restoration, whereas the net nitrification rate was negatively correlated with MAT. Generally, soil pH was the main factor affecting soil inorganic N, whereas elevation, soil microbial abundance, SOC or C:N, and climatic factors mainly affected soil net N mineralization and nitrification rates. Conclusion: Vegetation restoration was beneficial to soil N accumulation and is likely to decrease the risk of N loss in warmer regions given the reduced potential nitrification rate with increased MAT in the karst region of Southwest China.
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View more >Purpose: Soil nitrogen (N) availability plays an important role in determining ecosystem structure and function. However, the variation patterns of soil N availability under different vegetation restoration strategies along climatic gradients in the ecologically fragile karst region of China have been poorly understood. Methods: Soil N variables, including total N (TN), inorganic N [ammonium (NH ) and nitrate (NO )], and rates of net N mineralization and nitrification were measured following managed (plantation forest) and natural (spontaneous regeneration) vegetation restoration along a climatic gradient in the karst region of southwestern China. Results: Compared to that in the cropland, soil TN and NH concentrations significantly increased in both vegetation restoration strategies after 15 years of cropland abandonment. The net N mineralization and nitrification rates were lower in both vegetation restoration strategies compared with those in cropland and secondary forest. There were no significant differences in the soil N variables between the two vegetation restoration strategies. Furthermore, soil NO was positively correlated with mean annual temperature (MAT) following vegetation restoration, whereas the net nitrification rate was negatively correlated with MAT. Generally, soil pH was the main factor affecting soil inorganic N, whereas elevation, soil microbial abundance, SOC or C:N, and climatic factors mainly affected soil net N mineralization and nitrification rates. Conclusion: Vegetation restoration was beneficial to soil N accumulation and is likely to decrease the risk of N loss in warmer regions given the reduced potential nitrification rate with increased MAT in the karst region of Southwest China.
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Journal Title
Journal of Soils and Sediments
Note
This publication has been entered as an advanced online version in Griffith Research Online.
Subject
Earth sciences
Environmental sciences
Agricultural, veterinary and food sciences
Science & Technology
Life Sciences & Biomedicine
Soil Science
Ecology