Results 21 to 30 of about 1,353 (93)
Read the free Plain Language Summary for this article on the Journal blog. Abstract The stoichiometric imbalance caused by nitrogen (N) deposition typically exacerbates phosphorus (P) limitation in plants. However, it remains unclear whether this effect extends to soil microbes, particularly those in the rhizosphere.
Jipeng Wang +5 more
wiley +1 more source
为了研究氮沉降对次生林土壤碳氮组分和酶活性的影响,以华西雨屏区湿性常绿阔叶次生林为对象,从2014年1月起进行野外定位模拟氮沉降试验,分别设置对照(CK,+0 g/(m2·a))、低氮(LN,+5 g/(m2·a))和高氮(HN,+15 g/(m2·a))3个氮添加水平。在氮沉降进行27个月后,按照腐殖质层和淋溶层表层进行取样,测定不同土层土壤总有机碳(TOC)、可浸提溶解性有机碳(EDOC)、易氧化碳(ROC)、全氮(TN)、硝态氮(NO3--N)和铵态氮(NH4+-N)含量以及蔗糖酶、脲酶 ...
孙宇 +10 more
doaj
High nitrogen enrichment buffers plant photosynthesis against herbivory damage
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
生物质煤气废水是一种新出现的高浓度氨氮有机废水。作者采用化学沉淀法去除该废水中的氨氮,研究了不同沉淀剂、pH、温度和搅拌时间对氨氮去除效果的影响。结果表明,MgCl2+Na3PO4·12H2O明显优于其他沉淀剂组合。当n(Mg2+)∶n(NH4+)∶n(PO43-)=1∶1∶1、pH10.0、温度30℃、搅拌时间30min时,废水中的氨氮质量浓度从处理前的222mg/L降到17mg/L,去除率为92.3%。
张文华 +4 more
doaj +2 more sources
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
为探究大气氮沉降增加导致的土壤团聚体结构变化规律及其对土壤水分入渗性能的影响,在贡嘎山针叶成熟林和中龄林内分别设计2种氮肥形态[(NH4)2SO4、KNO3]和4个浓度水平(0,10,20,40 kg/(hm2·a)N)的添加试验,研究不同形态大气氮沉降对亚高山森林土壤团聚体结构和土壤水分入渗特征的影响。结果表明:(1)随施氮量增加,中龄林土壤大团聚体含量逐渐增加,土壤持水量、孔隙度和水分稳定入渗率逐渐增大;成熟林土壤大团聚体含量、土壤持水量、孔隙度和水分稳定入渗率均表现出先增加后降低的趋势;(2 ...
郭海云, 王根绪, 孙守琴
doaj
焦化废水属于典型的高氨氮难降解有毒有害工业废水,其对传统生物处理工艺和深度处理工艺都提出了很高的挑战。以某焦化废水处理站为实例,介绍了焦化废水的水质特点、工艺流程、构筑物参数和设备选型,分析了运行效果、出水水质以及运营成本。工程实际运行效果表明,采用预处理-两级A/O-磁混凝沉淀-多相催化臭氧氧化的工艺路线对焦化废水进行处理,废水COD、氨氮和总氮的去除率分别为98.4%、98.6%和88.5%,出水的COD≤80 mg/L,氨氮≤10 mg/L,总氮≤20 mg/L,达到或优于 ...
张志超, 牛涛, 于豹, 石伟
doaj +2 more sources
Dutch landscapes have lost insect‐pollinated plants over the past 87 years
This study implies that Dutch landscapes are losing insect‐pollinated plant species, which is likely due, at least in part, to the decline in pollination services. Our results of quantifying the decline in insect‐pollinated plants support the necessity and urgency of taking conservation initiatives.
Kaixuan Pan +3 more
wiley +1 more source
Summary Global change has accelerated local species extinctions and colonizations, often resulting in losses and gains of evolutionary lineages with unique features. Do these losses and gains occur randomly across the phylogeny? We quantified: temporal changes in plant phylogenetic diversity (PD); and the phylogenetic relatedness (PR) of lost and ...
Josep Padullés Cubino +33 more
wiley +1 more source
为探究荒漠草原土壤微生物特征对短期氮添加的响应,以宁夏荒漠草原为对象,参照国内外同类研究和当地的氮沉降量,设置N0、N1、N2、N3、N4的5个处理,其纯氮添加量分别为0,2.5,5,10,15 g/(m2·a),以尿素为氮源进行为期2年的氮添加试验,对不同氮添加处理下荒漠草原浅层土壤微生物特征进行了研究。结果表明:(1)随氮添加量的增加,荒漠草原0—20 cm土层土壤铵态氮含量呈升高的变化趋势,硝态氮含量呈先升高后下降的变化趋势。在0—10 cm土层,N1、N2、N3 ...
宋珂辰 +5 more
doaj +2 more sources

