Lincoln University, Faculty of Agriculture and Life Sciences, Department of Soil and Physical Sciences, PO Box 84, Lincoln, 7647, New Zealand.
Lincoln University, Faculty of Agriculture and Life Sciences, Department of Ecology, PO Box 84, Lincoln, 7647, New Zealand.
Plant Physiol Biochem. 2019 Apr;137:213-221. doi: 10.1016/j.plaphy.2019.02.008. Epub 2019 Feb 14.
Biowastes are unwanted materials of biological origin. They include biosolids, dairy shed effluent, and sawdust. When applied to soil, biowastes can provide plant nutrients, but also introduce heavy metals, pathogens, or xenobiotics. Biowastes could improve degraded or low-fertility soils and generate revenue through the production of non-food products such as essential oils. We grew New Zealand native plants, mānuka (Leptospermum scoparium J.R. Forst & G. Forst) and kānuka (Kunzea robusta de Lange & Toelken) in series of greenhouse experiments in low-to-medium-fertility soils (Bideford clay loam, Lismore stony silt loam, and Pawson silt loam) amended with either biosolids (up to 13500 kg N ha equiv.), biosolids + sawdust (1:0.5-1250 kg N ha equiv.) and dairy shed effluent (200 kg N ha equiv.). Two types of biosolids from Kaikoura (KB) and Christchurch City Council (CB) were used in the experiments. CB (1500 kg N ha equiv.) and dairy shed effluent (200 kg N ha equiv.) increased the biomass of L. scoparium by up to 120% and 31%, and K. robusta by up to 170% and 34%, respectively. Adding sawdust to KB increased the biomass of L. scoparium and K. robusta although it offset the L. scoparium growth increase in the KB-only treatment. The growth response of K. robusta to biowastes was greater than L. scoparium with oil production in K. robusta increasing by up to 211% when 1500 kg N ha equiv. of CB was applied to Lismore stony silt loam. Generally, the treatments had a negligible effect on oil concentration in all the soil types, except for the KB + sawdust treatment, which increased the oil concentration by 82%. Most of the EOs' major components were unaffected by biowaste addition in the soils, although some components increased in the Bideford clay loam following KB and KB + sawdust application. Biosolids increased foliar concentrations of Zn, Cu, and Cd, but these were below risk-threshold concentrations. Applying CB (up to 1500 kg N ha equiv.) to low-fertility soils is recommended to establish ecosystems dominated by L. scoparium and K. robusta that annually would produce ca. 100 kg ha of EOs worth US$ 26k and 24k, respectively. Adding sawdust to CB could have environmental benefits through reduction of N leaching. Field trials are warranted to elucidate critical ecological variables and production economics in biowaste management.
生物废物是指具有生物来源的无用物质。它们包括生物固体、奶制品棚舍废水和木屑。当应用于土壤时，生物废物可以提供植物养分，但也会引入重金属、病原体或外来化合物。生物废物可以改善退化或低肥力土壤，并通过生产非食用产品（如精油）来产生收入。我们在一系列温室实验中用新西兰本地植物曼努卡（Leptospermum scoparium J.R. Forst & G. Forst）和卡努卡（Kunzea robusta de Lange & Toelken）进行了种植，这些实验使用了添加了生物固体（高达 13500kg N ha 当量）、生物固体+木屑（1:0.5-1250kg N ha 当量）和奶制品棚舍废水（200kg N ha 当量）的低-中肥力土壤（比德福德粘壤土、利斯莫尔多石粉壤土和鲍森粉壤土）。实验中使用了来自凯库拉（Kaikoura）和克赖斯特彻奇市议会（Christchurch City Council）的两种生物固体。克赖斯特彻奇市议会（1500kg N ha 当量）和奶制品棚舍废水（200kg N ha 当量）使 L. scoparium 的生物量增加了高达 120%和 31%，K. robusta 的生物量增加了高达 170%和 34%。在 KB 中添加木屑增加了 L. scoparium 和 K. robusta 的生物量，尽管它抵消了仅用 KB 处理时 L. scoparium 生长的增加。K. robusta 对生物废物的生长反应大于 L. scoparium，当在利斯莫尔多石粉壤土中施加 1500kg N ha 当量的 CB 时，K. robusta 的产油量增加了高达 211%。一般来说，除了 KB+木屑处理外，这些处理对所有土壤类型中的油浓度都没有显著影响，在该处理中，油浓度增加了 82%。生物废物的添加在土壤中对大多数精油的主要成分没有影响，但在施加 KB 和 KB+木屑后，比德福德粘壤土中的一些成分增加了。生物废物增加了叶片中的 Zn、Cu 和 Cd 浓度，但这些浓度低于风险阈值浓度。建议在低肥力土壤中施加 CB（高达 1500kg N ha 当量），以建立以 L. scoparium 和 K. robusta 为主导的生态系统，每年可生产约 100kg ha 的精油，价值分别为 26k 美元和 24k 美元。在 CB 中添加木屑可以通过减少氮淋失来带来环境效益。需要进行田间试验来阐明生物废物管理中的关键生态变量和生产经济。
