Biodiv Sci ›› 2022, Vol. 30 ›› Issue (1): 21243.  DOI: 10.17520/biods.2021243

Special Issue: 昆虫多样性与生态功能

• Review • Previous Articles     Next Articles

Effects of organic planting on arthropod diversity in farmland: A meta-analysis

Fangqian Huang, Chao Wang, Mingqing Liu, Qiuhui Chen, Xiao Han(), Lei Wang(), Yunguan Xi, Jibing Zhang   

  1. Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042
  • Received:2021-06-20 Accepted:2021-09-22 Online:2022-01-20 Published:2022-01-29
  • Contact: Xiao Han,Lei Wang

Abstract:

Aims: Organic planting is widely considered an environment-friendly agricultural management pattern that plays a crucial role in the protection of agricultural biodiversity. The change of arthropod biodiversity is proposed as a key ecological indicator for agricultural sustainability. However, the effects of organic planting on arthropod biodiversity remain inconsistent in published studies, which may have resulted from the durations of organic planting, land use and cropping systems across the individual studies. The diverse results from previous studies could weaken the practicability of their conclusions in policymaking, which highlighted the necessity of conducting a meta-analysis to provide a generalized understanding of the effects of organic planting on arthropod diversity. This study aims to quantify the impact of organic planting on arthropod biodiversity using meta-analysis and provide scientific support for the formulation of ecological compensation policy under organic planting.

Methods: This meta-analysis conducted a literature review of peer-reviewed papers published before the end of 2020 which compared the impacts of organic and conventional planting on arthropod biodiversity. The results from 75 experimental sites, which contained 227 paired valid datasets, were selected for our analysis. To distinguish between the sources of variation for the responses of biodiversity to organic planting, the paired measurements were further subdivided into subgroups according to the factors of duration, land use, crop variety, pesticide application frequency in conventional planting, and arthropod functional groups.

Results: The results showed that compared with conventional planting, organic planting significantly improved the richness, abundance, and evenness of arthropods by the rate of 34.95%, 64.95%, and 12.09%, respectively. The abundance of the natural enemies of arthropods increased by 71.80% (P < 0.05) while the abundance of pests decreased by 10.46% under organic planting. The richness of the natural enemies and pests under organic planting were both increased by 22.50% and 31.03% respectively, relative to conventional planting (P < 0.05). The application of pesticides significantly decreased the arthropod biodiversity in conventional planting. Compared with the organic planting, an increase in the time of pesticide application in the conventional planting lead to decreases in the arthropod richness and evenness of arthropods by 13.54% and 2.64%, respectively. The responses of arthropod richness and abundance to organic planting were significantly positive when the duration was equal to or exceeded three years. The positive effect of organic planting on arthropod abundance in paddy fields was 4.7 times higher than that in dryland (P < 0.05), but the responses of richness and evenness to organic planting were comparable between paddy and dryland (P > 0.05). The responses of arthropod richness, abundance, and evenness to organic planting under the vegetable system were 81.46%, 74.14%, and 18.55%, respectively (P < 0.05); and under the tea-planting system were 48.86%, 49.06%, 30.88% (P < 0.05), respectively. The benefits of organic planting on arthropod biodiversity under the cropping systems of vegetable and tea were demonstrated to be more significant than that under other cropping systems.

Conclusions: Our meta-analysis suggests that organic planting plays an important role in protecting and improving biodiversity in croplands by increasing the abundance of natural enemies and decreasing pests abundance. The frequency of pesticide application was observed to be the key factor which significantly regulates the change of arthropod biodiversity. To promote the positive effects of organic planting on the protection of biodiversity in cropland, policymakers should not only to encourage the implementation of organic planting in regions where necessary conditions are satisfied, but also facilitate the ecological innovation of conventional planting by introducing the principles, concepts, and technologies of organic planting into conventional planting. This will be of more practical significance to agricultural biodiversity conservation in China.

Key words: agricultural biodiversity, organic planting, conventional planting, arthropod, meta-analysis