Fencing enclosure alters nitrogen distribution patterns and tradeoff strategies in an alpine meadow on the Qinghai-Tibetan Plateau

NWIPB OpenIR

	Fencing enclosure alters nitrogen distribution patterns and tradeoff strategies in an alpine meadow on the Qinghai-Tibetan Plateau
	Chen, Xiaopeng; Zhang, Tao; Guo, Ruiying; Li, Haiyan; Zhang, Rui; Degen, A. Allan; Huang, Kewei; Wang, Ximing; Bai, Yanfu; Shang, Zhanhuan
	2021
发表期刊	CATENA
卷号	197
摘要	The grasslands of Qinghai-Tibetan Plateau have become extremely degraded, resulting in widespread deficiency of soil N. In efforts to restore degraded lands, fencing enclosure has been used extensively. However, the effect of fencing on N allocation patterns and nutritional strategy of alpine plants are equivocal. In this study, we used N-15 tracer (CO ((NH2)-N-15)(2), 10 g N m(-2)) to examine the allocation and distribution of N in plants and soil in grasslands either grazed heavily by livestock or fenced for three years in an alpine meadow of Northern Tibet. The N-15 recovery (N-15(rec)) in shoots of the fenced enclosure increased by 207% in grasses, decreased by 103% in forbs, and did not change in sedges when compared to the grazed meadow. The N-15(rec) in shoots accounted for only 1.97% and 4.65% of the total N in the grazed and fenced meadows, respectively. Fencing increased soil N-15 content at 0-5 cm depth by 6.9%, but decreased the content at 5-10 cm depth by 11.7%. The results demonstrated that fencing altered the soil N distribution by increasing N-15 rec in top soil and by decreasing N-15(rec) in subsurface soil. In addition, fencing had no impact on root N-15 storage (33%-39%), N-15 losses (9.6%-12.5%) and soil available N-15(rec) (NH4+ -N, NO3--N and light fraction organic N), but decreased root:shoot N-15(rec) ratio by 49.8% (16.9:1 in grazed and 8.4:1 in fenced grassland). Fencing increased soil organic carbon, total N and NO3--N concentrations, which indicated that the strategy of the plants was to allocate relatively more N to roots in nutrient-poor soil (grazed) but relatively more N to shoots in nutrient-rich soil (fenced).
关键词	N-15 tracing Grazing exclusion Nutrition strategy Alpine meadow
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/60864
专题	中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Chen, Xiaopeng,Zhang, Tao,Guo, Ruiying,et al. Fencing enclosure alters nitrogen distribution patterns and tradeoff strategies in an alpine meadow on the Qinghai-Tibetan Plateau[J]. CATENA,2021,197.
APA	Chen, Xiaopeng.,Zhang, Tao.,Guo, Ruiying.,Li, Haiyan.,Zhang, Rui.,...&Shang, Zhanhuan.(2021).Fencing enclosure alters nitrogen distribution patterns and tradeoff strategies in an alpine meadow on the Qinghai-Tibetan Plateau.CATENA,197.
MLA	Chen, Xiaopeng,et al."Fencing enclosure alters nitrogen distribution patterns and tradeoff strategies in an alpine meadow on the Qinghai-Tibetan Plateau".CATENA 197(2021).