NITROGEN-FIXATION ASSOCIATED WITH THE NEW-ZEALAND MANGROVE (AVICENNIA-MARINA (FORSK) VIERH VAR RESINIFERA (FORST F) BAKH)
NITROGEN-FIXATION ASSOCIATED WITH THE NEW-ZEALAND MANGROVE (AVICENNIA-MARINA (FORSK) VIERH VAR RESINIFERA (FORST F) BAKH)
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DOI：
10.1128/aem.49.4.955-959.1985
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发表时间：
1985-01-01
影响因子：
4.4
通讯作者：
SILVESTER, WB
中科院分区：
文献类型：
--
作者：
HICKS, BJ;SILVESTER, WB
采用乙炔还原法和~（15）N_2吸收法测定了新西兰北岛2个地点红树林的固氮酶活性。0-10 mm表层沉积物中固氮酶活性（C_2H_2还原）与颗粒有机质分解干重呈显著正相关（r = 0.91，n = 17），与光照无关。根系活性与表层10 mm根系干重无相关性（r =-0.01，n = 13）。在空气下乙炔还原速率的季节性和样品变化范围为0.4-50.0 μ mol C2 H4 m-2 h-1，并且乙炔还原在厌氧气氛中被抑制。N2固定率的分解叶片从表面测量的15 N2吸收范围从5.1-7.8 nmol的N2克（干重）-1小时-1和乙炔减少固定的平均摩尔比为4.5：1。厌氧条件抑制了分解叶片中的固氮酶活性，这与光照无关。固氮酶活性也与气载体。这种活动是光依赖性的，可能是由于一个或多个物种的眉藻目前作为一种真菌。活动率一般在100-500 nmol的C2 H4 pneumatophore-1 h-1在夏季，但值高达1500 nmol的C2 H4 pneumatophore-1 h-1。
Nitrogenase activity in mangrove forests at 2 locations in the North Island, New Zealand, was measured by acetylene reduction and 15N2 uptake. Nitrogenase activity (C2H2 reduction) in surface sediments 0-10 mm deep was highly correlated (r = 0.91, n = 17) with the dry weight of decomposing particulate organic matter in the sediment and was independent of light. The activity as not correlated with the dry weight of roots in the top 10 mm of sediment (r = -0.01, n = 13). Seasonal and sample variation in acetylene reduction rates ranged from 0.4-50.0 .mu.mol of C2H4 m-2 h-1 under air and acetylene reduction was depressed in anaerobic atmospheres. N2 fixation rates of decomposing leaves from the surface measured by 15N2 uptake ranged from 5.1-7.8 nmol of N2 g (dry weight)-1 h-1 and the mean molar ratio of acetylene reduced to N2 fixed was 4.5:1. Anaerobic conditions depressed the nitrogenase activity in decomposing leaves, which was independent of light. Nitrogenase activity was also associated with pneumatophores. This activity was light dependent and was probably attributable to one or more species of Calothrix present as an epiphyte. Rates of activity were generally between 100-500 nmol of C2H4 pneumatophore-1 h-1 in summer, but values up to 1500 nmol of C2H4 pneumatophore-1 h-1 were obtained.