Nitrification potentials in early successional black locust and in mixed hardwood forest stands in the southern Appalachians, USA
Nitrification potentials in early successional black locust and in mixed hardwood forest stands in the southern Appalachians, USA
复制标题
美国阿巴拉契亚山脉南部早期演替刺槐和阔叶混交林的硝化潜力
DOI：
10.1007/bf02180195
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发表时间：
1986
期刊：
影响因子：
4
通讯作者：
W. Swank
中科院分区：
文献类型：
--
作者：
F. Montagnini;B. Haines;L. Boring;W. Swank
美国阿巴拉契亚山脉南部的 Coweeta 水文实验室测量了刺槐（刺槐）、早期演替流域 (WS6) 上的松树混合阔叶林 (WS6) 以及位于相邻混合阔叶流域 (WS14) 上的较老的橡树山核桃林中的土壤氮矿化和硝化潜力以及土壤溶液化学。刺槐和松树混合阔叶林的早期演替林分高于较老的生长分水岭的橡树山核桃林。氨化速率是控制早期演替林硝化作用的主要因素。没有证据表明较老的橡树-山核桃森林地区的土壤硝化作用受到抑制。在早期演替分水岭内，刺槐地区的净矿化和硝化速率至少是松树与硬木混合林地区的两倍。 3月份刺槐林0~15 cm土壤中交换性硝酸盐浓度高于松混阔叶林，7月份刺槐优势地0~15、16~30和31~45 cm深度的交换性硝酸盐浓度也较高。刺槐下的土壤溶液硝酸盐浓度高于松树混合硬木下的土壤溶液硝酸盐浓度。以固氮刺槐为主的地区具有较高的氮矿化和硝化速率，导致早期演替流域土壤柱中硝酸盐淋溶损失的可能性较高。
Soil nitrogen mineralisation and nitrification potentials, and soil solution chemistry were measured in black locust (Robinia pseudo-acacia L.), in pine-mixed hardwood stands on an early successional watershed (WS6), and in an older growth oak-hickory forest located on an adjacent, mixed hardwood watershed (WS14) at Coweeta Hydrologic laboratory, in the southern Appalachian mountains, U.S.A. Nitrification potentials were higher in black locust and pine-mixed hardwood early successional stands than in the oak-hickory forest of the older growth watershed. Ammonification rates were the main factor controlling nitrification in the early successional stands. There was no evidence of inhibition of nitrification in soils from the older growth oak-hickory forest site.Within the early successional watershed, black locust sites had net mineralisation and nitrification rates at least twice as high as those in the pine mixed-hardwood stands. Concentrations of exchangeable nitrate in the soil of black locust stands were higher than in pine-mixed hardwoods at 0–15 cm in March and they were also higher at 0–15, 16–30 and 31–45 cm depth in the black locust dominated sites in July. Soil solution nitrate concentrations were higher under black locust than under pine-mixed hardwoods. Areas dominated by the nitrogen fixing black locust had greater nitrogen mineralisation and nitrification rates, resulting in higher potential for leaching losses of nitrate from the soil column in the early successional watershed.