Skinulienė Lina, Marcinkevičienė Aušra, Butkevičienė Lina Marija, Steponavičienė Vaida, Petrauskas Ernestas, Bogužas Vaclovas
Agroecosystems and Soil Sciences Department, Vytautas Magnus University, K. Donelaičio Str. 58, 44248 Kaunas, Lithuania.
Plants (Basel). 2022 May 10;11(10):1279. doi: 10.3390/plants11101279.
In this study, our investigated hypothesis was that different pre-crops would have different effects on earthworm activity and soil CO emissions. We also hypothesized that a pre-crop clover-timothy mixture would perform best in terms of increasing the share of organic carbon in soil and, in this way, contribute to improving the sustainability of agroecosystems. The aim of this study was to explore the residual effects of using a 50-year-term of three different crop rotations and a continuous bare fallow period on soil CO emissions by investigating the soil earthworm populations, soil agrochemical properties, and winter wheat yields. A field experiment was carried out from 2016 to 2017 at Vytautas Magnus University in Lithuania (54°53' N, 23°50' E). The experiment was conducted in crop stands of winter wheat cv. 'Skagen', which were sown in three crop rotations with different pre-crops and a continuous bare fallow period. The pre-crop used for winter wheat in the cereal crop rotation (CE) was a vetch and oat mixture for green forage, LEG-CER; the pre-crop used for winter wheat in the field with row crops (FWR) crop rotation was black fallow, FAL-CER; the pre-crop used for winter wheat in the Norfolk (NOR) crop rotation was a clover-timothy mixture, GRS-CER; and finally, continuous bare fallow, FAL-CONTROL, was used as well. The highest soil CO emission intensity was determined after the pre-crops that left a large amount of plant residues (clover and timothy mixture) in the soil. Plant residues remaining after the pre-crop had the greatest effect on the number of earthworms in the soil after the harvesting of winter wheat. Winter wheat had the best yield when grown in grass and legume sequences. Crop rotation sequences that included perennial grasses accumulated higher contents of total nitrogen and organic carbon. The best values for the productivity indicators of wheat were obtained when it was grown after a fallow crop fertilized with cattle manure. An appropriate crop rotation that promotes the steady long-term contribution of organic matter and increases the content of organic carbon in the soil will have a positive effect on the agrochemical, biological, and physical properties of soil and agroecosystem sustainability; moreover, these effects cannot be achieved by technological means alone.
在本研究中，我们调查的假设是不同的前茬作物会对蚯蚓活动和土壤二氧化碳排放产生不同影响。我们还假设，就增加土壤中有机碳的比例而言，前茬三叶草-梯牧草混合物的表现最佳，并以此方式有助于提高农业生态系统的可持续性。本研究的目的是通过调查土壤蚯蚓种群、土壤农用化学性质和冬小麦产量，探索使用50年的三种不同作物轮作和连续裸地休耕期对土壤二氧化碳排放的残留影响。2016年至2017年在立陶宛的维陶塔斯·马格努斯大学（北纬54°53′，东经23°50′）进行了田间试验。试验在冬小麦品种‘斯卡根’的作物田中进行，该品种冬小麦以三种不同前茬作物和连续裸地休耕期进行轮作播种。谷类作物轮作（CE）中冬小麦的前茬作物是用作青饲料的巢菜和燕麦混合物，LEG-CER；大田作物（FWR）轮作田中冬小麦的前茬作物是冬闲，FAL-CER；诺福克（NOR）轮作中冬小麦的前茬作物是三叶草-梯牧草混合物，GRS-CER；最后，还采用了连续裸地休耕，FAL-CONTROL。在前茬作物在土壤中留下大量植物残体（三叶草和梯牧草混合物）之后，测定出最高的土壤二氧化碳排放强度。前茬作物残留的植物残体对冬小麦收获后土壤中的蚯蚓数量影响最大。冬小麦在禾本科和豆科轮作序列中生长时产量最佳。包含多年生禾本科植物的作物轮作序列积累了更高的总氮和有机碳含量。当小麦在施过牛粪肥的休闲作物之后种植时，获得了最佳的小麦生产力指标值。适当的作物轮作能够促进有机物质的长期稳定贡献并增加土壤中有机碳的含量，这将对土壤的农用化学、生物学和物理性质以及农业生态系统的可持续性产生积极影响；此外，这些影响无法仅通过技术手段实现。
