Results 11 to 20 of about 653,168 (147)

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, Volume 40, Issue 4, Page 983-1000, April 2026.
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

Dutch landscapes have lost insect‐pollinated plants over the past 87 years

open access: yesJournal of Applied Ecology, Volume 61, Issue 6, Page 1323-1333, June 2024.
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

滴灌施氮对春玉米氮素吸收、土壤无机氮含量及氮素平衡的影响

open access: yesShuitu Baochi Xuebao, 2018
为解决吉林省半干旱区滴灌施肥条件下氮肥合理施用问题,通过2年(2015—2016年)田间试验,研究了覆膜滴灌条件下施氮量(0,70,140,210,280,350 kg/hm2)对春玉米产量、氮素吸收利用、土壤剖面无机氮含量变化及氮素平衡的影响。结果表明:施氮量在70~210 kg/hm2范围内玉米产量随施氮量的增加显著增加,当施氮量超过210 kg/hm2后,处理间产量无显著差异;将玉米产量(y)与施氮量(x)拟合,得出最佳施氮量分别为195.1,201.0 kg/hm2 ...
侯云鹏   +7 more
doaj  

Trade‐off between soil carbon sequestration and net ecosystem economic benefits for paddy fields under long‐term application of biochar

open access: yesGCB Bioenergy, Volume 16, Issue 1, January 2024.
The use of biochar increased greenhouse gas (GHG) emissions but countered the harm caused by GHG emissions by considerable soil carbon sequestration resulting in a negative carbon footprint. Furthermore, the use of biochar lowered the proportion of CH4 and N2O, demonstrating that biochar usage has a considerable positive effect on GHG emissions ...
Zhuoxi Chen   +4 more
wiley   +1 more source

长期不同施肥措施水稻土可矿化氮与微生物量氮关系的研究

open access: yesShuitu Baochi Xuebao, 2007
采用短期淹水密闭培养法、长期淹水密闭培养-间歇淋洗法及氯仿薰蒸法,探讨不施氮肥、施氮肥、氮肥 有机肥、氮肥 有机肥 放萍4种施肥措施,连续16年长期定位试验水稻土的可矿化氮及微生物量氮的变化.结果表明:经过16年培肥及水稻种植,与不施氮肥相比,单施化学氮肥使水稻土可矿化氮数量极显著下降(p<0.01),化学氮肥与有机肥配施可极显著地提高水稻土可矿化氮数量(p<0.01);而化学氮肥及化学氮肥与有机肥配施均可极显著增加水稻土微生物量氮的数量(p<0.01),但以单施化学氮肥增加的幅度最大 ...
张玉玲   +4 more
doaj   +2 more sources

施氮对小麦产量和氮素径流损失及氮肥投入阈值的研究

open access: yesShuitu Baochi Xuebao, 2018
为明确巢湖流域小麦季氮肥投入阈值,在连续3年田间试验条件下,研究了(2012—2014年)不同氮肥水平下(N0、N1、N2、N3、N4、N5分别为0,157.5,210.0,262.5,310.0,420.0 kg/hm2)小麦产量、植株氮素积累量、氮肥利用率、土壤无机氮残留量(0—20 cm)及氮素径流流失;同时,利用回归方程模型对其间的相关关系进行拟合。结果表明:(1)与不施氮肥相比,施用氮肥可不同程度提高小麦产量,其中以N3处理增加的比例最大,为64.8%。利用二次函数分析,当施用氮肥超过290 ...
徐云连   +5 more
doaj  

河北太行山山前平原葡萄园土壤硝态氮累积特征及影响因素

open access: yesShuitu Baochi Xuebao, 2022
为进一步摸清农户生产实践条件下果园土壤硝态氮分布特征及影响因素,以河北太行山山前平原的保定地区葡萄园为研究对象,调查28个果园生产管理现状,测定分析葡萄园和临近农田共31个样点0—200 cm土壤硝态氮含量、累积量及主要影响因素。结果表明:葡萄生产中氮肥施用量偏高,每季平均为297 kg/hm2,过量的养分投入导致氮素在土壤中累积,0—200 cm土层硝态氮淋洗现象明显,平均累积量高达1 555 kg/hm2。不同树龄、施氮量、灌溉量水平下,土壤硝态氮含量有所不同,但均表现出随土层深度增加而增加的趋势 ...
郭路航   +6 more
doaj   +2 more sources

施氮量对冀西北春玉米氮肥利用率和土壤硝态氮时空分布的影响

open access: yesShuitu Baochi Xuebao, 2011
在田间条件下研究了施氮量对春玉米产量、氮肥利用率和土壤硝态氮时空分布的影响,旨在为冀西北春玉米氮肥优化管理提供理论依据。研究结果表明,春玉米产量随施氮量的增加而提高,当施氮量高于225 kg/hm2时,春玉米产量和氮肥利用率显著降低。从春玉米播种前到收获后,不施氮处理0-90 cm各土层硝态氮含量不断降低,施氮处理0-30 cm和30-60 cm土层硝态氮含量呈先上升后迅速下降并保持稳定的趋势,而60-90 cm土层硝态氮在春玉米生长后期有增加的趋势;春玉米收获后随着土层深度的增加,硝态氮呈波浪式下降 ...
王激清, 刘社平, 韩宝文
doaj  

施肥与灌水对硝态氮在土壤中残留的影响

open access: yesShuitu Baochi Xuebao, 2005
通过田间试验研究不同施氮量与灌水量对春玉米和冬小麦田土壤中硝态氮分布与累积的影响,结果表明,春玉米收获后0~2 m土壤中累积硝态氮185.7~748.0 kg/hm2,其中1 m以上占57.9%~70.1%。由于施用氮肥而增加的硝态氮占施N量的1.8%(N 112.5 kg/hm2),50.7%(N 225 kg/hm2),56.7%(N 337.5 kg/hm2)和77.0%(N450 kg/hm2)。不施N和施N 112.5 kg/hm2时春玉米田土壤剖面没有明显累积峰;施N等于或高于225 kg ...
高亚军 李生秀 李世清 田霄鸿 王朝辉 郑险峰 杜建军
doaj   +2 more sources

施氮对"双低"油菜吸氮特性及氮素生理效率的影响

open access: yesShuitu Baochi Xuebao, 2006
采用盆栽试验研究施氮对双低油菜吸氮特性及产量的影响。结果表明,植株氮素累积量,施氮处理从苗期到抽苔末期迅速增加,抽苔末期到开花末期下降,开花末期后有所回升,但仍没有超过抽苔末期的氮素累积量;不施氮处理与施氮处理有类似的变化趋势,但变化幅度明显小于施氮处理,而且开花末期后的氮素累积量超过了抽苔末期。无论施氮与否,营养器官含氮量随生育期的进程持续下降,而生殖器官含氮量施氮时持续下降,不施氮时则呈单峰曲线。干物质累积最大速率出现的日期,不施氮处理明显早于施氮处理。氮素生理效率,施氮处理在角果发育期最高 ...
宋海星   +5 more
doaj  

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