Resource Limitations on Soil Microbial Activity in an Antarctic Dry Valley
Resource Limitations on Soil Microbial Activity in an Antarctic Dry Valley
复制标题
南极干谷土壤微生物活动的资源限制
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
L. Greenfield
中科院分区：
文献类型：
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作者：
A. Sparrow;E. Gregorich;D. Hopkins;P. Novis;B. Elberling;L. Greenfield
尽管南极干谷土壤在地球上一些最恶劣的环境条件下发挥作用，但重要的生物活动集中在景观中的小区域。这些生产区是有机物中碳和氮的来源，并重新分配到周围生物贫瘠的土壤中。我们进行了为期 3 年的重复现场实验，涉及简单（葡萄糖和 NH4Cl）和复杂（甘氨酸和湖泊碎屑）形式的 C 和 N 土壤改良剂，以评估南极干旱山谷土壤微生物活动的资源限制。所有底物的呼吸反应都很缓慢，对 NH4Cl 的反应显着但较弱，随后 2 年后对所有底物产生更广泛的反应，并且在实验室培养中在添加底物 3 年后进行。这种反应表明，土壤微生物群落受到氮的限制，当这种限制得到缓解时，生物体就能够获取它们以前无法代谢的储存的碳。在实验室条件下添加碳和氮底物对呼吸速率的影响比原位测量的响应速率更快、更显着。由于可能限制田间微生物获取土壤资源的空间限制在实验室培养中已被消除，因此这一发现凸显了获取这些土壤资源的严重空间限制。
Although Antarctic dry valley soils function under some of the harshest environmental conditions on the planet, there is significant biological activity concentrated in small areas in the landscape. These productive areas serve as a source of C and N in organic matter redistributed to the surrounding biologically impoverished soils. We conducted a 3-yr replicated field experiment involving soil amendment with C and N in simple (glucose and NH4Cl) and complex (glycine and lacustrine detritus) forms to evaluate the resource limitations on soil microbial activity in an Antarctic dry valley. The respiratory response for all substrates was slow, with a significant but weak response to NH4Cl, followed by a more widespread response to all substrates after 2 yr and in laboratory incubations conducted 3 yr after substrate addition. This response suggests that the soil microbial community is N limited and, when that constraint is alleviated, the organisms are able to access a pool of stored C that they could not metabolize before. The effects of added C and N substrates on respiration rates under laboratory conditions were more rapid and significant than the response rates measured in situ. Because the spatial constraints that had probably limited access to soil resources by microorganisms in the field would have been removed in the laboratory incubation, this finding highlights the severe spatial constraints on access to resources in these soils.
影响因子：
9.7
作者：
D. Hopkins;A. Sparrow;L. Shillam;L. English;P. Dennis;P. Novis;B. Elberling;E. Gregorich;L. Greenfield
通讯作者：
D. Hopkins;A. Sparrow;L. Shillam;L. English;P. Dennis;P. Novis;B. Elberling;E. Gregorich;L. Greenfield
影响因子：
8.8
作者：
Hartley, Iain P.;Hopkins, David W.;Wookey, Philip A.
通讯作者：
Wookey, Philip A.