Results 11 to 20 of about 7,285 (204)

减氮配施缓释氮肥对棉田土壤酶活性和氮素吸收利用的影响

open access: yesShuitu Baochi Xuebao, 2022
为探明减氮配施缓释氮肥对棉田土壤酶活性和氮素吸收利用的影响,通过试验研究减氮、配施不同比例缓释氮肥对棉花土壤理化性质、酶活性、无机氮含量、氮肥利用率及棉花产量的影响。试验选用"新陆早64号"棉花品种,设置2种施氮方式,分别为常规全施尿素(T2)和缓释氮肥与尿素不同比例配施(US),配施处理按照施氮量设3个水平,分别为不减氮U0.8S0.2(T3)、U0.6S0.4(T4),减氮20% U0.6S0.2(T5)、U0.4S0.4(T6),减氮40% U0.4S0.2(T7)、U0.2S0.4(T8 ...
邱悦   +5 more
doaj  

尿素与复合氮肥增效剂配施对水稻氮素利用的影响

open access: yesShuitu Baochi Xuebao, 2006
采用^15N-尿素进行盆栽和田间试验,研究了复合氮肥增效剂用量、尿素与复合氮肥增效剂配施对水稻生长、籽粒产量和氮素吸收利用的影响。结果表明,适宜用量(施氮量的20%)的复合氮肥增效剂能显著促进水稻幼苗生长发育;尿素全量配施复合氮肥增效剂不影响水稻生长,能显著提高水稻植株Ndff%、氮吸收总量,氮素利用率和^15N的吸收量,尿素减量5%~15%(即减少施氮7.8~23.7kg/hm^2)配施复合氮肥增效剂基本上不影响水稻生长、籽粒产量和吸氮总量,能显著提高氮素的农学效率、生理效率和氮素利用率;植株吸氮总量、
田秀英, 王正银
doaj   +2 more sources

Nitrogen Transports and Transformations in Mangrove Sediments using Nitrogen Isotope Techniques in China [PDF]

open access: yes, 2012
人类活动对生态系统的影响日益扩大,过量施肥、化石燃料的燃烧等引发的氮(N)负荷迅速增加。陆地生态系统过剩的N通过流域汇集至河口和海岸,威胁着海洋生态系统的健康。目前,全球N循环正致力于揭示河口和海岸地区N的源汇格局及主导机制。红树林湿地广泛分布于热带、亚热带河口和海岸地区,作为陆源营养盐入海过渡带,在缓解陆源N输入方面扮演着重要角色,成为了研究的热点。 本研究利用N稳定同位素技术,将现场培养与室内模拟培养相结合,揭示了我国东南沿海典型河口和海湾红树林湿地沉积物总氮沉积、固氮作用、反硝化作用 ...
李颖
core  

Ultrafast Catalytic Decomposition Reaction Using a ZIF‐67@Celluolose Nanofiber Composite‐Based Cobalt/ Nitrogen Co‐Doped Nanoporous Carbon for Water Treatment

open access: yesRare Metals, EarlyView.
ABSTRACT Recently, cobalt/nitrogen co‐doped materials have emerged as heterogeneous catalysts to activate peroxymonosulfate (PMS) and have been applied to advanced oxidation processes for environmental remediation. However, their recyclability and reusability remain major barriers to practical application.
Wen‐Kai Zhu   +11 more
wiley   +1 more source

The Effect of N2O Emission Mitigation by Growing Soybeans Instead of Other Crops [PDF]

open access: yes, 2016
农业是重要的温室气体排放源之一,而在农业生产过程中施用氮肥是引起农业温室气体排放的主要原因。因此,如何合理有效的施用氮肥对减少农业温室气体排放、减缓全球气候变化至关重要。鉴于此,对通过合理施用氮肥从而减少温室气体排放的减排措施进行成本效益分析,将有助于我们找到具有经济效益的农业温室气体减排方法。目前,相关减排措施研究主要集中在农田测土配方施肥、改良施肥(缓释肥和长效肥)上。得益于与豆类作物共生的根瘤菌具有的固氮作用,豆类作物相比其他农作物施用更少的氮肥,从而排放更少的氧化亚氮(N2O)。因此 ...
许俊武
core  

Elevation, soil pH and calcium availability shape regional and local scale spatial patterns of PhoD gene abundance in tropical and subtropical forests

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Organic phosphorus mineralization is a critical process in the phosphorus cycle, governing phosphorus bioavailability for plants. The PhoD gene, which encodes the key enzyme alkaline phosphatase, serves as a valuable biomarker for this process.
Sandhya Mishra   +3 more
wiley   +1 more source

Fabricating Highly Efficient Ternary Mn–CeOx/Co3O4 Catalysts for Low Temperature Thermal Desorption of Persistent Perfluorooctanoic Acid in Soil

open access: yesRare Metals, Volume 45, Issue 1, January 2026.
ABSTRACT Developing efficient catalytic thermal desorption systems is of great significance in the field of sustainable soil remediation. Herein, novel Mn–Ce solid solution modified Co3O4 nanocrystals were successfully prepared for the removal of perfluorooctanoic acid (PFOA) in soil.
Yu‐Hao Liu   +8 more
wiley   +1 more source

Gradient distributions of nitrogen and organic carbon in the soils from inland to tidal flat in the Yellow River Delta [PDF]

open access: yes, 2014
黄河三角洲是我国典型的通过黄河冲积泥沙填海造陆形成的近代沉积区。区域受到黄河冲积、沉积等自然过程和农业耕种熟化等人类活动的双重影响。本研究通过在黄河三角洲地区内陆到河口海湾不同距离采集典型土壤类型剖面发生层样品,探讨土壤有机碳、总氮等生源要素的空间分布规律,为阐明我国典型海岸带地区陆源碳、氮的输送及循环特征提供基础依据。研究结果表明,黄河三角洲内陆与河口地区呈现出完全不同的土壤碳、氮分布规律。表层土壤碳、氮含量在黄河沿岸及三角洲南部均表现出由陆向海逐级递减的空间分布特征 ...
李远   +4 more
core   +1 more source

Nitrogen Anchoring Effect Triggering Improved Reversible Hydrogen Storage of Mg(BH4)2

open access: yesRare Metals, Volume 45, Issue 1, January 2026.
ABSTRACT This research uncovered the influence of nitrogen‐doped MXene Ti3CN on the reversible hydrogen storage properties of Mg(BH4)2. The Mg(BH4)2‐20Ti3CN composite began releasing hydrogen at a temperature of 80°C. In addition, the composite discharged over 8.8 wt% hydrogen at a comparatively lower temperature of 270°C, whereas the pure Mg(BH4)2 ...
Zhen‐Xuan Ma   +7 more
wiley   +1 more source

小麦氮素营养与籽粒灌浆期氮素转移的研究进展

open access: yesShuitu Baochi Xuebao, 2004
对小麦氮素营养与籽粒灌浆期氮素转移研究进展进行了综述。过去进行的大量研究结果表明,小麦籽粒最终累积的氮素有相当一部分来自于灌浆期间营养器官中氮素的再转移,来自营养器官氮(内源氮)与土壤中新吸收氮(外源氮)的比例基本上是1:2。因此,花后营养器官氮素营养水平是决定小麦籽粒产量、籽粒中氮素累积量和蛋白质含量的一个重要因素。灌浆期间营养器官氮素向籽粒发生转移的同时,常常伴随着叶片光合性能的下降和叶片的衰老。不同基因型品种在灌浆期的氮素转移程度不同,表现为随品种演替,旗叶、茎秆和叶鞘中氮素的输出率增加 ...
李世清 王瑞军 张兴昌 伍维模 邵明安
doaj   +2 more sources

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