反硝化作用在氮循环中扮演什么角色？
What role does denitrification play in the nitrogen cycle?
反硝化菌在缺氧条件下把硝酸盐还原成氮气（N2）返回大气，是氮循环“出口”，能削减水体富营养化，但也可能把氮肥变气体损失掉。
Denitrifying bacteria in low-oxygen conditions convert nitrate back to N2 gas, the cycle's 'exit' that curbs aquatic eutrophication but also loses fertilizer as gas.
难度 专业 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Odum & Barrett,《Fundamentals of Ecology》第5版,Brooks/Cole,2004
E. P. Odum and G. W. Barrett, Fundamentals of Ecology, 5th ed., Brooks/Cole, 2004
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL3334843W：Fundamentals of ecology
#反硝化 #硝酸盐 #氮气
大气氮沉降怎么导致生物多样性下降？
How does atmospheric nitrogen deposition lower biodiversity?
化石燃料与化肥使活性氮随降雨沉降，富营养化让少数喜氮植物生长旺盛、遮盖并排挤其他物种，贫瘠生境的特有植物首先消失。
Fossil fuels and fertilizers send reactive nitrogen down as deposition; eutrophication lets a few nitrogen-loving plants outcompete others, and specialist plants of poor soils vanish first.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Odum & Barrett,《Fundamentals of Ecology》第5版,Brooks/Cole,2004
E. P. Odum and G. W. Barrett, Fundamentals of Ecology, 5th ed., Brooks/Cole, 2004
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL3334843W：Fundamentals of ecology
#氮沉降 #富营养化 #生物多样性
人类工业固氮（哈伯法）与自然生物固氮的规模对比如何？
How does human industrial (Haber-Bosch) nitrogen fixation compare with natural biological fixation?
20 世纪以来工业固氮使全球活性氮产量翻倍，如今人为固氮总量已与自然生物固氮相当甚至更多，深刻改变了全球氮循环并带来污染。
Since the 1900s, Haber-Bosch fixation has roughly doubled reactive nitrogen creation; anthropogenic fixation now rivals or exceeds natural biological fixation, reshaping the global N cycle and causing pollution.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
G. Tyler Miller,《Living in the Environment》Cengage 多版
G. T. Miller, Living in the Environment, Cengage Learning, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL66394W：Living in the environment
#哈伯法 #工业固氮 #氮循环
为什么磷被称为“峰值的”、不可再生的资源？
Why is phosphorus called a 'peaking', non-renewable resource?
磷主要来自有限的磷矿石，无法像氮那样靠大气补充；开采峰值临近、集中产地少，且农业流失造成水体富营养化，形成“缺而污染并存”的矛盾。
Phosphorus comes mainly from finite phosphate rock, not replenished from air like nitrogen; peak extraction nears, supply is concentrated, yet farm runoff causes eutrophication—a scarcity-pollution paradox.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
Global Phosphorus Research
global P research
#磷 #峰值资源 #富营养化
农业径流造成“死区”（缺氧）的机制是什么？
How do agricultural runoff create 'dead zones' (hypoxia)?
化肥随雨水汇入河口，刺激藻类暴发性繁殖，藻类死亡后被细菌分解耗光底层氧气，形成缺氧水体使鱼虾大量死亡，如墨西哥湾夏季死区。
Fertilizer runoff feeds algal blooms at estuaries; decaying algae are decomposed by bacteria that consume bottom oxygen, creating hypoxic water that kills fish and shrimp, e.g., the Gulf of Mexico dead zone.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Odum & Barrett,《Fundamentals of Ecology》第5版,Brooks/Cole,2004
E. P. Odum and G. W. Barrett, Fundamentals of Ecology, 5th ed., Brooks/Cole, 2004
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL3334843W：Fundamentals of ecology
#死区 #缺氧 #富营养化
撒哈拉的沙尘为什么会飞越大西洋滋养亚马逊?沙尘暴也有温柔的一面?
How does Saharan dust fly across the Atlantic to feed the Amazon — do dust storms have a gentle side?
每年约1.8亿吨撒哈拉沙尘升空,一部分搭乘东风急流跨越五千公里落在亚马逊盆地——所携的磷正是热带雨林最缺的营养(土壤淋溶严重,磷依赖外援)。研究估算这份补给可抵消水土流失损失的相当比例磷,堪称地球最大的生态补贴。沙尘亦有气候角色:落入海洋的铁元素喂养固碳浮游植物,高空沙尘影响云形成与辐射平衡。当然,近距沙尘暴是健康灾难——PM10爆表、呼吸道疾病激增,治理关键在源头植被与放牧管理。
Roughly 180 million tonnes of Saharan dust take wing each year, part riding easterly jets five thousand kilometers to fall on the Amazon — carrying phosphorus, the nutrient rainforest soils chronically lack through leaching; studies estimate this intercontinental delivery offsets a large share of hydrological phosphorus losses, Earths biggest ecological subsidy. Dust also plays climate roles: iron landing on oceans feeds carbon-fixing plankton, and high-altitude dust shapes clouds and radiation. Up close though, storms are health disasters — PM10 spikes and respiratory surges — managed best by source-zone vegetation and grazing control.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Yu 等,《The fertilizing role of African dust in the Amazon rainforest》,Atmospheric Chemistry and Physics 第15卷,2015
H. Yu et al., The fertilizing role of African dust in the Amazon rainforest, Atmospheric Chemistry and Physics 15, 2015
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-119-22117-3 (2006, Wiley)
#沙尘输送 #生物地球化学循环 #跨洋养分
农民施下的氮肥为什么只有一半左右真正进了庄稼?没被吸收的氮去了哪里、惹了什么祸?
Why does only about half of the nitrogen fertiliser farmers apply ever reach the crop, where does the rest end up, and what trouble does it cause?
因为施肥量普遍超过作物当季的吸收能力,全球农田一半以上的氮素未被收获带走。它们沿三条路离开农田:挥发成氨气与一氧化二氮——后者是效力远超二氧化碳的温室气体;以硝酸盐形态淋入地下水,威胁饮用水安全;随径流入河入海,引发藻类暴发与近海低氧死区。对策是测土配方精量施肥、缓控释肥、硝化抑制剂并与豆科轮作固氮,让更多氮长进籽粒而非散逸进环境。
Fertiliser is routinely spread far beyond what a crop can absorb in a single season, so worldwide more than half of applied nitrogen leaves the field unharvested. It escapes down three routes: volatilising into ammonia and nitrous oxide, a greenhouse gas vastly more potent than CO2; leaching as nitrate into the groundwater that feeds drinking wells; and washing off into rivers and seas, triggering algal blooms and low-oxygen dead zones. Soil-tested precision dosing, slow-release fertilisers, nitrification inhibitors and rotations with nitrogen-fixing legumes all aim to steer nitrogen into grain instead of the environment.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
Zhang X等论文《Managing nitrogen for sustainable development》,Nature 2015
Zhang X et al., 'Managing nitrogen for sustainable development', Nature, 2015
独立核验依据 · Independent verification: 核验依据 1 EUROPEPMC 标识 26595273：Managing nitrogen for sustainable
#氮肥利用率 #面源污染 #精准施肥