Bekchanova Madina, Campion Luca, Bruns Stephan, Kuppens Tom, Lehmann Johannes, Jozefczak Marijke, Cuypers Ann, Malina Robert
Centre for Environmental Sciences, Research Group Environmental Economics, UHasselt-Hasselt University, Agoralaan Gebouw D, 3590, Diepenbeek, Belgium.
Centre for Environmental Sciences, Research Group Environmental Biology, UHasselt-Hasselt University, Agoralaan Gebouw D, 3590, Diepenbeek, Belgium.
Environ Evid. 2024 Feb 22;13(1):3. doi: 10.1186/s13750-024-00326-5.
Biochar is a relatively new development in sustainable agricultural management that can be applied to ameliorate degraded and less fertile soils, especially sandy-textured ones, to improve their productivity with respect to crop production through improved nutrient availability. However, as the literature has shown, the response of sandy-textured soils to biochar varies in terms of effect size and direction. Therefore, the present study systematically reviewed the available evidence to synthesize the impact of biochar amendments on aspects of the nutrient cycle of sandy-textured soils.
Both peer-reviewed and gray literature were searched in English in bibliographic databases, organizational web pages, and Internet search engines. Articles underwent a two-stage screening (title and abstract, and full-text) based on predefined criteria, with consistency checks. Validity assessments were conducted, utilizing specifically designed tools for study validity. Data extraction involved categorizing the various properties of the nutrient cycle into nine main Soil and Plant Properties (SPPs), each of which was studied independently. Nine meta-analyses were performed using a total of 1609 observations derived from 92 articles. Comparing meta-averages with and without correction for publication bias suggests that publication bias plays a minor role in the literature, while some indication for publication bias is found when accounting for heterogeneity by means of meta-regressions.
According to the results, soil total and available nitrogen [N], phosphorous [P] and potassium [K], plant nutrient level, and potential cation exchange capacity (CEC) increased by 36% (CI [23%, 50%]), 34% (CI [15%, 57%]), 15% (CI [1%, 31%]), and 18% (CI [3%, 36%), respectively, and NO emission and mineral nutrient leaching decreased by 29% (CI [- 48%, - 3%]) and 38% (CI [- 56%, - 13%). On average, however, biochar had no effect on soil mineral nitrogen and nutrient use efficiency. Publication bias was identified in the response of effective CEC. After corrections for publication bias, the response shifted from 36% to a negative value of - 34% (CI [- 50%, - 14%]). Meta-regression found that the effect modifiers experimental continent, biochar application rate, and soil pH, explain result heterogeneity. Stronger responses came from the continent of South America, higher application rates, and higher pH soils. Overall, biochar is found useful for many SPPs of nutrient cycling of sandy-textured soils, thereby contributing to increased crop yields in such soils.
生物炭是可持续农业管理领域一项相对较新的发展成果，可用于改良退化和肥力较低的土壤，尤其是沙质土壤，通过提高养分有效性来提高其作物生产能力。然而，正如文献所示，沙质土壤对生物炭的反应在效应大小和方向方面存在差异。因此，本研究系统地回顾了现有证据，以综合生物炭改良对沙质土壤养分循环各方面的影响。
在书目数据库、组织网页和互联网搜索引擎中用英文搜索了同行评审文献和灰色文献。文章根据预定义标准进行两阶段筛选（标题和摘要以及全文），并进行一致性检查。利用专门设计的研究有效性工具进行有效性评估。数据提取包括将养分循环的各种属性分类为九个主要的土壤和植物属性（SPP），每个属性都独立进行研究。使用从92篇文章中获得的总共1609个观测值进行了九项荟萃分析。比较有无发表偏倚校正的荟萃平均值表明，发表偏倚在文献中起的作用较小，而在通过荟萃回归考虑异质性时发现了一些发表偏倚的迹象。
结果显示，土壤全氮和有效氮、磷、钾、植物养分水平以及潜在阳离子交换容量（CEC）分别增加了36%（置信区间[23%，50%]）、34%（置信区间[15%，57%]）、15%（置信区间[1%，31%]）和18%（置信区间[3%，36%]），氮氧化物排放和矿质养分淋失分别减少了29%（置信区间[-48%，-3%]）和38%（置信区间[-56%，-13%]）。然而，平均而言，生物炭对土壤矿质氮和养分利用效率没有影响。在有效CEC的反应中发现了发表偏倚。校正发表偏倚后，反应从36%变为-34%的负值（置信区间[-50%，-14%]）。荟萃回归发现，效应修饰因素实验大陆、生物炭施用量和土壤pH值可以解释结果的异质性。来自南美洲大陆更强的反应、更高的施用量以及更高pH值的土壤。总体而言，生物炭被发现对沙质土壤养分循环的许多SPP有用，从而有助于提高此类土壤的作物产量。
