为了研究湿地退化过程中土壤碳氮磷储量与生态化学计量变化,明确碳氮“汇”功能的变化和土壤碳、氮、磷的平衡关系,采用实地采样调查、室内分析与数理统计法,研究了若尔盖自然湿地保护区内未退化湿地沼泽(SW)、沼泽化草甸(SM)、草甸(ME)3种不同退化程度湿地的典型样地在碳氮磷含量、储量以及生态化学计量变化特征。结果表明,沼泽化草甸土与草甸土全剖面总有机碳、全氮含量较沼泽土分别降低了29.55%,6.52%和67.53%,40.04%,碳氮储量分别降低了67.49%,60.10%和85.14%,54.47 ...
叶 +7 more
doaj
研究黄土高原侵蚀环境下林地开垦后坡面土壤养分空间分布状况,确立林地开垦后侵蚀驱动的坡地土壤养分空间变异特征。以黄土高原丘陵区子午岭林地和开垦28年的侵蚀坡面为研究对象,分析土壤主要性质和养分含量的变化情况,运用经典统计学和地统计法分析坡面土壤基本性质和养分空间分布规律。林地开垦后坡面土壤pH增加了0.24个单位,有机质、全氮、全磷和铵态氮、硝态氮、速效磷和速效钾分别降低了13.77,1.14,0.10 g/kg和6.05,1.63,4.99,58.44 mg/kg。林地的土壤有机质 ...
王昭 +6 more
doaj
[Chemical diversity of dissolved organic matter revealed by ultra performance liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry]. [PDF]
Ma C, Ni HX, Qi YL.
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Testing AnnAGNPS for water quality modelling in the typical sub-watersheds in Jiulong River watershed [PDF]
在中国东南丘陵山区一中尺度流域———九龙江流域选取4个土地利用方式不一的典型小流域,借助GIS和相关资料率定模型参数,并通过对2003年4月至9月各小流域出口降雨水质水量的同步监测,检验了连续分布式参数模型(AnnualizedAGriculturalNonPointSourceModel,AnnAGNPS)的适用性.研究结果表明,模型对于地表径流量的模拟能力好于对泥沙和营养盐的模拟,对总磷和泥沙输出的模拟结果表现出了较大的不确定性.
张珞平 +3 more
core
Effects of Water and Nitrogen Management on Soil Nitrogen Metabolism Enzyme Activity and Wheat Nitrogen Utilization [PDF]
[Objective] To explore the effects of water and nitrogen management on soil nitrogen metabolism enzyme activity and wheat nitrogen utilization under irrigation based on soil moisture.
CUI Zhenkun +4 more
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Spatial distribution of vegetation and soil properties on the Ulan Bator-Fengzhen transect on the Mongolian Plateau [PDF]
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Comprehensive Geochemical Evaluation and Influencing Factors of Topsoil Nutrients in a Farming Area of Dabie Mountain in Western Anhui, China [PDF]
Western Anhui is an important precision agricultural area in China, characterized by diverse landforms and multiple soil types. To determine the spatial distribution of soil nutrient elements and their controlling factors, we analyzed 5 nutrient ...
Chao SONG +5 more
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为了探究海拔高度与土壤理化性质之间的关系,对秦岭火地塘林区不同海拔高度土壤理化性质进行研究。在不同海拔高度设置样地,对土壤进行分层取样,室内测定土壤pH值、有机质、全氮、全磷、全钾、有效氮、有效磷和有效钾含量。结果表明:(1)在不同采样深度下,随着土壤深度增加,除土壤pH值逐渐升高外,有机质、全氮、有效磷和有效钾的含量逐渐降低,其他指标无明显变化规律;(2)土壤pH值、有机质、全氮和有效磷含量与海拔之间有显著的相关关系,土壤pH值随海拔升高先逐渐升高,最高点出现在海拔1 800~2 000m ...
张巧明 +3 more
doaj
目的为了解秦岭水源地土壤结构及土壤氮变化对生态恢复的响应。方法基于秦岭水源地闵家河小流域不同土地利用的土壤样品数据,定量分析生态恢复下流域土壤侵蚀及全氮损失量,探究生态恢复对土壤团聚体组成、稳定性及全氮分布的影响。结果1)流域土壤侵蚀以微度侵蚀为主,发生轻度和中度侵蚀的区域占比仅为6.76%。农地土壤侵蚀模数和单位面积土壤全氮损失显著高于林地和草地,56.46%的土壤侵蚀和45.11%的土壤全氮损失源自农地且主要分布在流域中、下游区域。2)生态恢复显著提高土壤团聚体稳定性和大团聚体质量分数。与农地相比较,
徐明珠 +8 more
doaj
Authenticity Detection of Egg White Powder Using Near-Infrared Spectroscopy Based on Improved One-Dimensional Convolutional Neural Network Model [PDF]
An improved one-dimensional convolutional neural network (1D-CNN) model for the authenticity detection of egg white powder was constructed based on near-infrared spectroscopy (NIRS). This model required no spectral preprocessing.
ZHU Zhihui, LI Wolin, HAN Yutong, JIN Yongtao, YE Wenjie, WANG Qiaohua, MA Meihu
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