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991.
992.
秸秆或粉煤灰添加对砂姜黑土持水性及小麦抗干旱胁迫的影响 总被引:2,自引:1,他引:1
针对黄淮海平原典型中低产土壤砂姜黑土黏粒含量较高,土壤有效水分库容较低,严重限制作物生产的现状,该文采用盆栽试验,研究了不同外源改性物料的添加对土壤持水性能及小麦生理的影响,以期获得农田水分管理过程中的关键参数。盆栽试验设置常规氮磷钾(control,CK),常规氮磷钾配施下的添加秸秆(straw returning,SR)、秸秆碳(straw carbon,SC)和粉煤灰(fly ash,FA)处理,维持土壤相对含水率在80%,培育小麦至抽穗期,开展为期10 d的干旱胁迫试验。结果显示SR和SC处理提高了土壤持水能力,且处理间的差异较小;FA处理因其表面富含大量疏水性结晶矿物,土壤相对含水率下降较快,迟效水含量显著低于其余处理,但土壤速效水含量显著提高。不同改性措施均有提高小麦叶片相对含水率,减轻干旱胁迫的趋势,但在极端干旱胁迫下,FA处理叶片相对含水率不仅明显低于其余处理,且作物体内积累大量丙二醛、过氧化氢等有害物质。田间管理中砂姜黑土相对含水率应维持在38%(SR)、36.5%(SC)和24.5%(FA)以上,当土壤相对含水率低于30.78%(SC)、28.43%(SR)和22.5%(FA)时将会对作物生理产生不可逆的伤害。鉴于秸秆优良的保水性能,粉煤灰“富水,不保水”的特性,秸秆与粉煤灰的配合施用将利于砂姜黑土的改良。相关机制值得进一步研究。 相似文献
993.
植保无人机低空低量施药雾滴沉积飘移分布立体测试方法 总被引:2,自引:2,他引:0
随着植保无人机在中国的广泛使用,植保无人机的沉积分布均匀性与雾滴飘移流失也引起各方面的重视。目前,针对植保无人机施药雾滴沉积飘移的测试方法较少,且着重于从沉积或飘移中某一方面分析植保无人机雾滴沉积飘移规律,未对作业中全方位的雾滴的沉积飘失规律进行系统测试。该文基于国际标准ISO22866和ISO24253建了1套针对低空低量植保无人机的立体测试方法,分别在地面布置沉积和飘移收集器,在空中架设立体沉积和空中飘移收集器,结合航拍影像所获取的植保无人机准确作业参数,对4个型号植保无人机分别搭载德国Lechler公司的IDK120-015和TR80-0067喷头进行了测试,系统分析了无人机周边的总沉积以验证方法准确性,计算了总地面沉降以表征可利用部分和空中耗散以评估环境风险。结果表明,各植保无人机地面沉积率在53.6%~76.6%,地面飘移率最高17.4%,空中飘移率可高达14.7%;该测试系统可收集62.4%~101.7%无人机喷洒出的雾滴。测试的4种植保无人机在搭载IDK喷头后均明显降低了雾滴飘移,但也同时降低地面沉积率;各植保无人机在搭载2种喷头时沉积规律不同,不同植保无人机设计需要选择不同喷头。该测试方法能够有效的收集并分析植保无人机在作业区域的雾滴立体分布状态,可为植保无人机综合评估提供新的参考依据。 相似文献
994.
Li Fayong Liang Xinqiang He Shuang Li Meiru Cao Yucheng Zhang Jin Tian Guangming 《Journal of Soils and Sediments》2020,20(2):629-640
Journal of Soils and Sediments - Laboratory incubation experiments using 15N stable isotope labeling and acetylene suppression techniques were conducted to compare the autotrophic nitrification and... 相似文献
995.
996.
Journal of Soils and Sediments - Soil bulk density and hydraulic conductivity are two of many key factors for vegetation establishment and the other way around. Variations in them may cause patchy... 相似文献
997.
He Yao Hu Yaxian Gao Xin Wang Rui Guo Shengli Li Xianwen 《Journal of Soils and Sediments》2020,20(4):1906-1919
Journal of Soils and Sediments - Erosion processes spatially redistribute soil particles and the associated carbon across landscapes. Their spatial redistribution pattern is governed by the... 相似文献
998.
Zheng Xiaomei Wu Jianfu Yan Xiao Qin Guobing Zhou Rongwei Wei Zongqiang 《Journal of Soils and Sediments》2020,20(11):3846-3856
Journal of Soils and Sediments - The effects of soil properties on biochar-induced soil phosphate sorption and availability are not well investigated. An alkaline biochar-induced soil phosphate... 相似文献
999.
Huijie Li Jiawei Wang Saif Ali Babar Iqbal He Zhang Shanshan Wang 《Soil Science and Plant Nutrition》2020,66(2):308-316
ABSTRACT Cotton is critical for phosphorus demands and very sensitive for its deficiency. However, identifying the effect of low-phosphorus tolerance on cotton growth, yield, and fiber quality by reducing phosphorus consumption. This may help to develop phosphorus-tolerant high-yielding cotton cultivars. In a two-year repeated (2015 and 2016) hydroponic experiment (using 0.01 and 1 mM KH2PO4), two cotton cultivars with phosphorus sensitivity (Lu 54; a low-phosphorus sensitive and Yuzaomian 9110; a low-phosphorus tolerant) were screened on the base of agronomic traits and physiological indices through correlation analysis, cluster analysis and principal component analysis from 16 cotton cultivars. Low phosphorus nutrition reduced the plant height, leaf number, leaf area, phosphorus accumulation and biomass in various organs of seedlings. The deficiency negatively affected the morphogenesis of seedlings, as well as yield and fiber quality. Further, these screened cultivars were tested in a pot experiment with 0, 50, 100, 150, 200 kg P2O5 ha?1 during 2016 and 2017. It was found to have a significant (P< 0.05) difference in boll number, lint yield, fiber strength, and micronaire at the harvest. Furthermore, after collectively analyzed the characteristics of Lu 54 and Yuzaomian 9110, there were six key indices that could improve the low phosphorus tolerance of cotton cultivars. These were root phosphorus accumulation, stem phosphorus accumulation percentage, leaf and total biomass of seedlings, seed cotton weight per boll and fiber length. 相似文献
1000.
ABSTRACT Zinc (Zn) deficiency is common worldwide and is a major limiting factor in the cultivation of Platycodon grandiflorum because most P. grandiflorum is cultivated on soils with slight or severe levels of Zn deficiency in China. To investigate the effects of soil Zn fertilization on P. grandiflorum and its residual effects on soil characteristics, a randomized complete block design was conducted at the experimental station of Shandong Agricultural University China in 2016–2018. In 2016, ZnSO4 · 7H2O was used as Zn fertilizer. The fertilizer levels of Zn fertilizer were designed as 0, 4, 6, 8 and 10 kg ha?1 and were denoted as CK, Zn4, Zn6, Zn8 and Zn10. No Zn fertilizer was used in 2017 and 2018. The results showed that soil Zn fertilization increased the quantity of soil bacteria, and actinobacteria, Zn8 and Zn10 treatments increased the soil fungal quantity in 2017, whereas the effect was observed only in the Z10 treatment in 2018. Soil Zn fertilization enhanced the activity of polyphenol oxidase, decreased that of phosphatase, and did not influence the invertase activity in both 2017 and 2018. Both the yield and the quality of P. grandiflorum in the succeeding three years increased due to the soil Zn fertilization in 2016. Overall, soil Zn application is a suitable approach to the cultivation of P. grandiflorum, and the residual effects of a one-time soil Zn fertilization could last at least two years. 相似文献