Department of Civil Engineering, Indian Institute of Technology Guwahati, 781039, India; Centre for Sustainable Polymers, Indian Institute of Technology Guwahati, 781039, India.
Department of Civil Engineering, Indian Institute of Technology Guwahati, 781039, India; Centre for Sustainable Polymers, Indian Institute of Technology Guwahati, 781039, India; Department of Chemical Engineering, Indian Institute of Technology Guwahati, India.
Sci Total Environ. 2022 Dec 10;851(Pt 2):158311. doi: 10.1016/j.scitotenv.2022.158311. Epub 2022 Aug 28.
Growing demand for plastic and increasing plastic waste pollution have led to significant environmental challenges and concerns in today's world. Bioplastics offer exciting new opportunities and possibilities where biodegradable and bio-based plastics are expected to be more eco-friendly and rely on renewable resources. With all its promises, evaluating its real impact and fate on the geoenvironment is paramount for promoting bioplastic use. This paper presents a systematic literature review to understand current bioplastic-soil research and the effects of its residues on the geoenvironment. 632 studies related to bioplastic research in soil since 1973 were identified and categorized into different relevant topics. Publication trend showed bioplastic-soil research grew exponentially after 2010 wherein field studies accounted to 33.1 % of the total studies and only about 9.7 % studied the effects of bioplastic residues on the geoenvironment. Majority of the lab studies were on development and subsequent stability of bioplastics in soil. Short-term studies (in months) dominated the longer-term studies and studies over 4 years were almost non-existent. Lab and field experiments often gave inconsistent results with seasonal, climatic and bio-geographical factors strongly influencing the field results and bioplastic stability in soil. Most existing studies reported significant effects for microbioplastic concentrations at or above 1 % w/w. Bioplastic residues were found to substantially affect soil C/N ratio, impact soil microbial diversity by favouring certain microbial taxa and alter soil physical structure by influencing soil aggregates formation. At higher concentrations, plant health and germination success were also negatively affected. Conclusively, the review found it important to focus more on long-term field experiments to better understand the degree and extent of bioplastic residue impact on soil physico-chemical properties, mechanical properties, soil biology, soil-bioplastic-plant response, nutrients and toxicity. There are also very few studies investigating contaminant transport and migration of micro or nano-bioplastics in soil.
对塑料的需求不断增长，以及日益严重的塑料废物污染，给当今世界带来了重大的环境挑战和问题。生物塑料提供了令人兴奋的新机会和可能性，可生物降解和基于生物的塑料有望更加环保，并依赖可再生资源。尽管生物塑料前景广阔，但评估其对地质环境的实际影响和命运对于促进生物塑料的使用至关重要。本文进行了系统的文献综述，以了解当前生物塑料-土壤研究以及其残留物对地质环境的影响。自 1973 年以来，共确定了 632 项与土壤中生物塑料研究相关的研究，并将其分为不同的相关主题。研究表明，2010 年后生物塑料-土壤研究呈指数级增长，其中田间研究占总研究的 33.1%，只有约 9.7%的研究关注生物塑料残留物对地质环境的影响。大多数实验室研究侧重于生物塑料在土壤中的开发和随后的稳定性。短期研究（以月为单位）占主导地位，长期研究较少，超过 4 年的研究几乎不存在。实验室和田间实验的结果往往不一致，季节性、气候和生物地理因素强烈影响田间结果和生物塑料在土壤中的稳定性。大多数现有研究报告称，在 1%（w/w）或以上的微生物塑料浓度下，会产生显著影响。生物塑料残留物被发现会极大地影响土壤 C/N 比，通过有利于某些微生物类群来影响土壤微生物多样性，并通过影响土壤团聚体的形成来改变土壤的物理结构。在较高浓度下，植物的健康和发芽成功率也受到负面影响。综上所述，该综述认为，更注重长期田间实验非常重要，以便更好地了解生物塑料残留物对土壤理化性质、机械性质、土壤生物学、土壤-生物塑料-植物反应、养分和毒性的影响程度和范围。也很少有研究调查微纳米生物塑料在土壤中的污染物迁移和运移。
