Phosphorus uptake in four tree species under nitrogen addition in subtropical China
Phosphorus uptake in four tree species under nitrogen addition in subtropical China
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中国亚热带施氮条件下四种树种的磷吸收量
DOI：
10.1007/s11356-017-9633-x
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发表时间：
2017-08-01
影响因子：
5.8
通讯作者：
Yin, Guangcai
中科院分区：
文献类型：
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作者：
Liu, Juxiu;Li, Yiyong;Yin, Guangcai
大气氮沉降是副热带地区中国的一个严重问题，这里N大量存在，而P缺乏。一些研究假设，N-2固定剂可以通过用固定的N-2交换土壤磷来克服磷限制。为了了解N-2固定剂能否在富N亚热带的中国上投入固定的N-2来生产胞外磷酸酶，以及是否能刺激丛枝菌根真菌吸收土壤P，进行了露天温室试验。将两种N-2固定植物(马占相思和红豆杉)和两种非N-2固定植物(木荷和马尾松)分别置于3个施氮量水平下：5.6 kg ha(-1)a(-1)(环境N)、15.6 kg ha(-1)a(-1)(中N)和20.6 kg ha(-1)a(-1)(高N)。我们发现，在富N亚热带的中国地区，植物对土壤磷的吸收能力具有物种特异性。在施氮量下，N-2固定剂的吸磷速率高于非N-2固定剂，这与N-2固定剂的土壤APA和AMF较高(p<；0.01)有关。然而，随着时间的推移，高N施用量对土壤微生物磷脂脂肪酸(PLFAs)含量的影响比非N-2固定剂更显著(p<；0.05)。结果表明，在亚热带中国地区环境氮沉降条件下，N-2固定剂比非N-2固定剂具有更高的吸磷能力。然而，未来持续的氮沉降可能会影响N-2固定剂对磷的吸收能力，因为高N加入量会降低土壤中N-2固定剂的微生物PLFA。
Atmospheric N deposition is a serious problem in subtropical China where N is present in large amounts but P is deficient. Several studies hypothesized that N-2 fixers can overcome phosphorus limitation by trading fixed N-2 for soil phosphorus. In order to know whether N-2 fixers could invest fixed N-2 in extracellular phosphatase production and could stimulate arbuscular mycorrhizal fungi (AMF) to acquire soil P in N-rich subtropical China, an open-air greenhouse experiment was carried out. Two N-2 fixers (Acacia mangium and Ormosia pinnata) and two non-N-2 fixers (Schima superba and Pinus massoniana) were exposed to three levels of N addition: 5.6 kg ha(-1) a(-1) (ambient N), 15.6 kg ha(-1) a(-1) (middle N), and 20.6 kg ha(-1) a(-1) (high N). We found that the capacity of plants to acquire soil P in N-rich subtropical China is species specific. The higher P uptake rates were found for N-2 fixers than non-N-2 fixers under N addition, which were related to the greater soil APA and higher AMF (p < 0.01) in the soil of N-2 fixers. However, with time, high N addition decreased more significant quantities of soil microbial phospholipid fatty acids (PLFAs) in the soil of N-2 fixers than that of non-N-2 fixers (p < 0.05). We conclude that N-2 fixers have higher P uptake capacity than non-N-2 fixers under ambient N deposition in subtropical China. However, continuing N deposition in the future might affect P uptake ability of N-2 fixers as high N addition would decrease soil microbial PLFAs of N-2 fixers.