Cuesta D, Taboada A, Calvo L, Salgado J M
Department of Biodiversity and Environmental Management, Area of Zoology, University of León, Campus de Vegazana s/n, E-24071 León, Spain.
Environ Pollut. 2008 Mar;152(2):394-402. doi: 10.1016/j.envpol.2007.06.073. Epub 2007 Sep 10.
We studied the short- and medium-term effects of experimental nitrogen fertilization (3 and 15 months after the treatment) on the arthropods of Calluna vulgaris heathlands in NW Spain. Three heathland sites were selected with two permanent plots per site: control and fertilized. Ammonium nitrate fertilizer (56 kg N ha(-1) yr(-1)) was applied monthly and insects were caught using pitfall traps. We found mainly species-level responses to nitrogen addition. Seven species (e.g. Lochmaea suturalis) showed a consistent trend (benefited or harmed) in both periods and were proposed as possible reliable indicators of the effects of nitrogen deposition in these ecosystems. We also found variable arthropod trophic-group responses: (a) herbivores (leaf beetles, true bugs) increased in abundance on a short-term scale; (b) predators (carabid beetles, true bugs) showed opposite and less clear responses in both periods. Further long-term studies are needed to determine the mechanisms underlying the observed arthropod responses.
我们研究了实验性氮肥施用（处理后3个月和15个月）对西班牙西北部普通石南灌丛节肢动物的短期和中期影响。选择了三个石南灌丛地点，每个地点有两个永久样地：对照样地和施肥样地。每月施用硝酸铵肥料（56千克氮/公顷·年），并使用陷阱诱捕器捕捉昆虫。我们主要发现了物种水平对氮添加的响应。七个物种（如缝叶蜂）在两个时期都表现出一致的趋势（受益或受害），并被提议作为这些生态系统中氮沉降影响的可能可靠指标。我们还发现节肢动物营养级组的反应各不相同：（a）食草动物（叶甲虫、椿象）在短期内数量增加；（b）捕食者（步甲、椿象）在两个时期表现出相反且不太明显的反应。需要进一步的长期研究来确定观察到的节肢动物反应背后的机制。
