Results 21 to 30 of about 7,285 (204)

Study on the nitrogen removal process and influencing factors in the rhizosphere of Sesuvium portulacastrum floating bed [PDF]

open access: yes, 2016
大气是地球氮元素储量最大的氮库,由于氮气的三键结构十分稳定,打开它所需的能量较高,因此在工业革命以前,主要靠闪电固氮和生物固氮将其转化为人和生物可以利用的含氮化合物。然而随着人类社会的不断发展,为了满足人们生产生活的需要,大量氮元素被通过工业的方式固定下来,并随着化肥的滥用积累在环境中,造成氮循环的破坏,并产生水体富营养化现象。富营养化带来的恶果就是水体藻类大量繁殖,溶解氧急剧降低,造成鱼虾等水生生物的死亡等。因此,想要根除富营养化现象就必须将水体过量的氮、磷营养盐从水体脱除 ...
仇元
core  

High nitrogen enrichment buffers plant photosynthesis against herbivory damage

open access: yesFunctional Ecology, Volume 40, Issue 1, Page 229-238, January 2026.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Herbivorous insects and nitrogen deposition are key drivers of ecosystem productivity under global change. However, their combined effects on plant photosynthesis, particularly during insect outbreaks, remain poorly understood in natural ecosystems.
Yongqiang Zhang   +6 more
wiley   +1 more source

Study on Geochemistry of Nutrient and Nutrient Criteria in Jiulong Estuary [PDF]

open access: yes, 2015
由于大量的人为输入河口的营养盐(特别是氮和磷),近海富营养化区域逐渐扩大。河口和近海水体的富营养化已经引起了全世界的广泛关注。水体富营养化对环境造成很多影响,比如水质恶化、赤潮爆发、生态系统结构改变、低氧和死亡区的出现以及大量的经济损失。研究河口营养盐循环,并建立合理的营养盐基准值保护河口及沿海水体的措施刻不容缓。 本研究融合多学科知识,对不同季节的九龙江河口地区进行了多个航次的现场采样和同位素培养,运用GIS技术并收集整理历史数据,揭示了九龙江河口营养盐时空变化、内部迁移转化过程以及水体营养盐浓度 ...
黄铮
core  

Plant functional trait dissimilarity drives plant mixture effects on fine root biomass and trait variations

open access: yesNew Phytologist, Volume 249, Issue 2, Page 764-776, January 2026.
Summary Fine roots are critical for soil resource uptake, yet how declining plant diversity alters fine root biomass (RB) and traits remains unclear. We tested how plant functional trait dissimilarity in shade tolerance, drought tolerance, growth rate, and nitrogen‐fixation ability drives variation in root attributes.
Sai Peng, Yakun Zhang, Han Y. H. Chen
wiley   +1 more source

脲醛缓释肥不同配比对小麦生长及土壤氮素养分的影响

open access: yesShuitu Baochi Xuebao, 2017
在黄淮海地区冬小麦中高产田采用小区试验,以普通尿素基施、普通尿素基施加追施作对比,研究脲醛氮占总氮30%,40%,50%,60%,70%的不同脲醛缓释掺混肥在田间的氮素养分释放特征,以及对土壤氮素养分、小麦产量、氮素利用率及经济效益的影响,探明合理施用脲醛缓释肥最优氮素配比,以达到增加产量、节约资源、增加经济效益的目的。结果表明:脲醛掺混肥氮素释放量在小麦生育进程中呈现高低再高低的变化过程,脲醛氮占总氮40%或50%最有利于土壤氮素供应,脲醛氮所占比例过大或过小,都不利于小麦整个生长期氮素供应 ...
周华敏   +5 more
doaj  

Genetic analysis and gene mapping of panicle branches stay-green trait in rice [PDF]

open access: yes, 2016
水稻是重要的粮食作物之一,全球一半以上的人口以大米为主食。随着世界人口的增长,人们正面临着越来越严重的粮食危机。如何增加水稻产量一直是作物育种以及植物学研究的重要目标。近年来水稻遗传育种工作者发现了一些成熟期叶片的叶绿素不降解或仅少量降解而使叶片仍保持绿色的持绿型水稻品种,研究发现其叶片持绿性状多数属多基因控制的数量遗传,少数属隐性主效基因控制的质量性状遗传,相关基因大多已被鉴定及克隆。迄今为止,尚未见穗枝梗持绿性状的研究报道。佳辐占系本课题组育成的优质高产早稻品种,已在生产上大面积推广应用 ...
王永杰
core  

Factors influencing fine roots decomposition rates in response to nitrogen addition vary across root characteristics

open access: yesFunctional Ecology, Volume 39, Issue 12, Page 3504-3516, December 2025.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Nitrogen (N) deposition strongly affects litter decomposition and nutrient release, thereby reshaping carbon cycling in terrestrial ecosystems. Although most studies have focused on above‐ground litter, the effects of N addition on fine root decomposition and their ...
Yuneng Wang   +5 more
wiley   +1 more source

基于15N同位素示踪盐渍化农田向日葵氮素利用规律

open access: yesShuitu Baochi Xuebao, 2022
为探明盐渍化农田不同施氮水平下向日葵氮素吸收利用规律,采用15N同位素示踪技术进行田间微区试验,以不施氮处理(N0)为对照,设计3种施氮水平(N1=150 kg/hm2、N2=225 kg/hm2、N3=300 kg/hm2),于向日葵成熟期测定植株和0—100 cm土层土壤15N同位素丰度及总氮含量,研究各处理肥料氮素的去向及其利用机制。结果表明:向日葵氮素吸收量随施氮量的增加而增加,成熟期作物氮素吸收量在N2水平较不施氮显著增加38.7%;土壤氮和肥料氮对作物当季氮素吸收的贡献比例为84.9%和15.
乔天, 刘霞, 杨威, 高宏远
doaj  

Research on Nitrogen Reduction Processes in Fujian Mangrove Sediments Using Nitrogen Stable Isotope in China [PDF]

open access: yes, 2017
近年来,由于人类活动频繁,导致大量营养盐输入水生系统中,造成严重的富营养化,威胁水生生物生长,污染饮用水,同时破坏水体的娱乐用途。当输入系统的氮不能通过生物地球化学作用被河流移除或滞留时,过量的氮大都带入海岸带河口,最终进入大陆架作为重要的氮汇途径,而这些过量氮素将会引起近岸海域富营养化及一系列环境问题。红树林是分布在热带和亚热带海岸河口地区潮间带开放的生态系统。其栖息地—海岸潮汐湿地—作为河口沉积区的重要组成,是全球碳、氮、磷的重要源、汇及转化器,因此成为了研究的热点 ...
杨晶鑫
core  

Nitrogen‐transforming microorganisms potentially facilitate the invasion of Moso bamboo (Phyllostachys edulis) into evergreen broadleaf forests

open access: yesFunctional Ecology, Volume 39, Issue 10, Page 2704-2716, October 2025.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Moso bamboo (Phyllostachys edulis) invasions into broadleaf forests can cause serious ecological problems, such as reducing biodiversity and disrupting community succession.
Ting Zhou   +5 more
wiley   +1 more source

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