Background

The influence of outdoor green space on microbial communities indoors has scarcely been investigated. Here, we study the associations between nearby residential green space and residential indoor microbiota.

Methods

We collected settled dust from 176 living rooms of participants of the ENVIRONAGE birth cohort. We performed 16S and ITS amplicon sequencing, and quantitative PCR measurements of total bacterial and fungal loads to calculate bacterial and fungal diversity measures (Chao1 richness, Shannon and Simpson diversity indices) and relative abundance of individual taxa. Green spaces were estimated within 50m and 100m buffers around the residential address. We defined total residential green space using high-resolution land-cover data, further stratified in low-growing (height<3m) and high-growing green (height>3m). We used land-use data to calculate the residential nature. We ran linear regression models, adjusting for confounders and other potential determinants. Results are expressed as units change for an interquartile range (IQR) increase in residential green space and their 95% confidence intervals (CI).

Results

After adjustment, we observed statistically significant associations between the indoor microbial diversity indices and nearby residential green space. For bacteria, the Shannon index was directly associated with residential nature (e.g. 0.08 units increase (CI:0.02,0.13) per IQR increase in nature within a 50m buffer). Fungal diversity was directly associated with high-growing residential green and inversely with low-growing green. For example, an IQR increase in high-growing green within a 50m buffer was associated with increases in 0.14 (CI:0.01,0.27) and 0.02 (CI:0.008,0.04) units in the Shannon and Simpson indices, respectively.

Conclusions

Nearby green space determines the diversity of indoor environment microbiota, and the type of green differently impacts bacterial and fungal diversity. Further research is needed to investigate in more detail possible microbial taxa compositions underlying the observed changes in indoor microbiota diversity and to explore their contribution to beneficial health effects associated with green space exposure.

中文翻译：

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住宅绿地可塑造室内微生物环境

背景

几乎没有研究室外绿地对室内微生物群落的影响。在这里，我们研究了附近住宅绿地与住宅室内微生物群之间的关联。

方法

我们收集了 ENVIR ON参与者的 176 个客厅的灰尘年龄出生队列。我们进行了 16S 和 ITS 扩增子测序，以及总细菌和真菌负荷的定量 PCR 测量，以计算细菌和真菌多样性测量（Chao1 丰富度、香农和辛普森多样性指数）和单个分类群的相对丰度。绿地估计在住宅地址周围 50m 和 100m 缓冲区内。我们使用高分辨率土地覆盖数据定义了总住宅绿地，进一步分为低生长（高度<3m）和高生长绿色（高度>3m）。我们使用土地利用数据来计算居住性质。我们运行线性回归模型，调整混杂因素和其他潜在决定因素。结果表示为住宅绿地四分位距 (IQR) 增加的单位变化及其 95% 置信区间 (CI)。

结果

调整后，我们观察到室内微生物多样性指数与附近住宅绿地之间存在统计学上的显着关联。对于细菌，香农指数与居住性质直接相关（例如，在 50m 缓冲区内，自然界每增加 0.08 个单位（CI：0.02,0.13））。真菌多样性与高增长的住宅绿地直接相关，与低增长的绿地成反比。例如，50m 缓冲区内高生长绿色的 IQR 增加分别与香农和辛普森指数中 0.14 (CI:0.01,0.27) 和 0.02 (CI:0.008,0.04) 单位的增加相关。

结论

附近的绿地决定了室内环境微生物群的多样性，而绿地类型对细菌和真菌多样性的影响也不同。需要进一步的研究来更详细地调查所观察到的室内微生物群多样性变化背后可能的微生物分类群组成，并探索它们对与绿色空间暴露相关的有益健康影响的贡献。