Nitrate production and availability in residential soils.
Nitrate production and availability in residential soils.
复制标题
住宅土壤中硝酸盐的产生和可用性。
DOI：
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发表时间：
2011
影响因子：
5
通讯作者：
M. Cadenasso
中科院分区：
文献类型：
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作者：
S. Raciti;P. Groffman;J. Jenkins;R. Pouyat;T. Fahey;S. Pickett;M. Cadenasso
美国住宅用地面积的迅速增加引起了人们对与氮肥有关的水污染的关注。硝酸盐（NO3-）是活性氮的形式，最容易受到淋溶和径流的影响;因此，如果我们要准确预测住宅扩建对水质的影响，就需要更深入地了解硝化作用和NO3（-）的可用性。特别是，很少有土地利用的历史，住房密度和住宅土壤的年龄影响NO3（-）池和通量，特别是在深度的评估。在这项研究中，我们使用了1米深的土芯，以评估潜在的净硝化和矿化，微生物呼吸和生物量，土壤NO3（-）和NH 4+池在32个住宅家庭草坪，以前的土地利用和年龄不同，但有类似的土壤类型。这些进行了比较，8个森林参考网站类似的土壤。我们的研究结果表明，住宅用地的变化增加了活性氮的池和生产，这对该地区的水质有明显的影响。然而，研究结果与通常的假设相矛盾，即住宅区土壤中NO3（-）的产生和可用性明显高于森林。而净硝化作用（128.6 +/- 15.5 mg m（-2）d（-1）vs. 4.7 +/- 2.3 mg m（-2）d（-1）;平均值+/- SE）和交换性NO3（-）（3.8 +/- 0.5 g/m2对0.7 +/- 0.3 g/m2）在本研究中住宅区土壤中显著高于森林土壤，与其他研究中的落叶林相比，这些NO3（-）产生和可用性的测量值仍然很低。第二个意想不到的结果是，目前的房主管理做法是不能预测NO3（-）的可用性或生产。这可能反映了施肥后无机氮的瞬时有效性。较高的住房密度和农业用地的历史是预测更大的NO3（-）在住宅土壤中的可用性。如果这些因素是很好的预测在更广泛的网站，他们可能是有用的指标NO3（-）的可用性和淋溶和径流潜力在景观尺度。
The rapid increase in residential land area in the United States has raised concern about water pollution associated with nitrogen fertilizers. Nitrate (NO3-) is the form of reactive N that is most susceptible to leaching and runoff; thus, a more thorough understanding of nitrification and NO3(-) availability is needed if we are to accurately predict the consequences of residential expansion for water quality. In particular, there have been few assessments of how the land use history, housing density, and age of residential soils influence NO3(-) pools and fluxes, especially at depth. In this study, we used 1 m deep soil cores to evaluate potential net nitrification and mineralization, microbial respiration and biomass, and soil NO3(-) and NH4+ pools in 32 residential home lawns that differed by previous land use and age, but had similar soil types. These were compared to eight forested reference sites with similar soils. Our results suggest that a change to residential land use has increased pools and production of reactive N, which has clear implications for water quality in the region. However, the results contradict the common assumption that NO3(-) production and availability is dramatically higher in residential soils than in forests in general. While net nitrification (128.6 +/- 15.5 mg m(-2) d(-1) vs. 4.7 +/- 2.3 mg m(-2) d(-1); mean +/- SE) and exchangeable NO3(-) (3.8 +/- 0.5 g/m2 vs. 0.7 +/- 0.3 g/m2) were significantly higher in residential soils than in forest soils in this study, these measures of NO3(-) production and availability were still notably low, comparable to deciduous forest stands in other studies. A second unexpected result was that current homeowner management practices were not predictive of NO3(-) availability or production. This may reflect the transient availability of inorganic N after fertilizer application. Higher housing density and a history of agricultural land use were predictors of greater NO3(-) availability in residential soils. If these factors are good predictors across a wider range of sites, they may be useful indicators of NO3(-) availability and leaching and runoff potential at the landscape scale.