Key laboratory of Nonpoint Source Pollution Control, Ministry of Agriculture and Rural Affairs of P. R. China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Key laboratory of Nonpoint Source Pollution Control, Ministry of Agriculture and Rural Affairs of P. R. China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Sci Total Environ. 2022 Jan 20;805:150441. doi: 10.1016/j.scitotenv.2021.150441. Epub 2021 Sep 20.
Excess phosphorus (P) leached from high fertiliser input cropping systems in northern China is having detrimental effects on water quality. Before improved management can be directed at specific soils and cropping system types estimates of P leached loss apportionment and mitigation potentials across the main soil (fluvo-aquic soil, FAS; cinnamon soil, CS; black soil, BS) areas and cropping systems (protected vegetable fields, PVFs; open vegetable fields, OVFs; cereal fields, CFs) are needed. The present study designed and implemented conventional fertilisation and low input system trials at 75 sites inclusive of these main soils and cropping system types in northern China. At all sites, a uniform lysimeter design (to 0.9 m depth) enabled the collection and analysis of leachate samples from 7578 individual events between 2008 and 2018. In addition, site-specific static and dynamic activity data were recorded. Results showed that annual total phosphorus (TP) leached losses across the main soil areas and cropping systems were 4.99 × 10 kg in northern China. A major finding was PVFs contributed to 48.5% of the TP leached losses but only accounted for 5.7% of the total cropping areas. The CFs and OVFs accounted for 40.3% and 11.2% of the TP leached losses, respectively. Across northern China, the TP leached losses in PVFs and OVFs were greatest in FAS areas followed by CS and BS areas. The higher TP leached losses in FAS areas were closely correlated with greater P fertiliser inputs and irrigation practices. From a management perspective in PVFs and OVFs systems, a decrease of P inputs by 10-30% would not negatively affect yields while protecting water quality. The present study highlights the importance of decreasing P inputs in PVFs and OVFs and supporting soil P nutrient advocacy for farmers in China.
中国北方高施肥作物系统淋失的过量磷（P）对水质产生了不利影响。在针对特定土壤和作物系统类型进行改进管理之前，需要估算主要土壤（冲积性水稻土、棕壤、黑土）和作物系统（设施蔬菜地、露地蔬菜地、旱作谷物地）的 P 淋失损失分配和缓解潜力。本研究在中国北方的 75 个地点设计和实施了常规施肥和低投入系统试验，这些地点包括上述主要土壤和作物系统类型。在所有地点，采用统一的淋溶仪设计（至 0.9 m 深度），收集和分析了 2008 年至 2018 年期间 7578 个淋溶事件的淋出液样本。此外，还记录了特定地点的静态和动态活动数据。结果表明，中国北方主要土壤和作物系统的年总磷（TP）淋失损失为 4.99×10kg。一个主要发现是，设施蔬菜地导致了 48.5%的 TP 淋失损失，但仅占总耕地面积的 5.7%。旱作谷物地和露地蔬菜地分别占 TP 淋失损失的 40.3%和 11.2%。在中国北方，设施蔬菜地和露地蔬菜地的 TP 淋失损失在冲积性水稻土地区最大，其次是棕壤和黑土地区。冲积性水稻土地区较高的 TP 淋失损失与较高的磷肥投入和灌溉实践密切相关。从设施蔬菜地和露地蔬菜地系统的管理角度来看，减少 10-30%的 P 投入不会对产量产生负面影响，同时还能保护水质。本研究强调了减少设施蔬菜地和露地蔬菜地 P 投入以及为中国农民提供土壤 P 养分宣传的重要性。
