Ruhr-Universität Bochum, Institute of Geography, Soil Science and Soil Ecology, Universitätsstrasse 150, 44801 Bochum, Germany.
Ruhr-Universität Bochum, Institute of Urban Water Management and Environmental Engineering, Universitätsstrasse 150, 44801 Bochum, Germany.
Environ Pollut. 2018 Feb;233:561-568. doi: 10.1016/j.envpol.2017.10.048. Epub 2017 Nov 5.
In many water-scarce countries, waste water is used for irrigation which poses a health risk to farmers and consumers. At the same time, it delivers nutrients to the farming systems. In this study, we tested the hypotheses that biochar can be used as a filter medium for waste water treatment to reduce pathogen loads. At the same time, the biochar is becoming enriched with nutrients and therefore can act as a fertilizer for soil amendment. We used biochar as a filter medium for the filtration of raw waste water and compared the agronomic effects of this "filterchar" (FC) and the untreated biochar (BC) in a greenhouse pot trial on spring wheat biomass production on an acidic sandy soil from Niger. The biochar filter showed the same removal of pathogens as a common sand filter (1.4 log units on average). We did not observe a nutrient accumulation in FC compared to untreated BC. Instead, P, Mg and K were reduced during filtration while N content remained unchanged. Nevertheless, higher biomass (Triticum L. Spp.) production in BC (+72%) and FC (+37%) treatments (20 t ha), compared with the unamended control, were found. There were no significant differences in aboveground biomass production between BC and FC. Soil available P content was increased by BC (+106%) and FC (+52%) application. Besides, mineral nitrogen content was reduced in BC treated soil and to a lesser extent when FC was used. This may be explained by reduced sorption affinity for mineral nitrogen compounds on FC surfaces. Although the nutrients provided by FC decreased, due to leaching in the filter, it still yielded higher biomass than the unamended control.
在许多水资源短缺的国家，废水被用于灌溉，这对农民和消费者的健康构成了威胁。与此同时，废水为农业系统提供了养分。在本研究中，我们检验了以下假设，即生物炭可用作废水处理的过滤介质，以减少病原体负荷。同时，生物炭会富集养分，因此可以作为土壤改良的肥料。我们使用生物炭作为过滤介质来过滤原废水，并在尼日尔的酸性沙质土壤上的温室盆栽试验中比较了这种“过滤炭”（FC）和未处理生物炭（BC）的农艺效果，用于春小麦生物量的生产。生物炭过滤器对病原体的去除效果与普通砂滤器相同（平均去除 1.4 个对数单位）。我们没有观察到 FC 与未处理的 BC 相比存在养分积累。相反，在过滤过程中 P、Mg 和 K 减少，而 N 含量保持不变。尽管如此，BC（+72%）和 FC（+37%）处理（20 吨/公顷）的生物量（小麦属）产量均高于未施肥对照，BC 和 FC 之间的地上生物量产量没有显著差异。BC 和 FC 的应用增加了土壤有效磷含量（BC 增加 106%，FC 增加 52%）。此外，BC 处理土壤中的矿质氮含量减少，而 FC 处理时则减少得较少。这可能是由于 FC 表面对矿质氮化合物的吸附亲和力降低所致。尽管 FC 提供的养分因过滤而淋失，但它仍产生了比未施肥对照更高的生物量。
