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张掖盆地1990s表土层深部土壤重金属分布特征及其来源分析
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作者 何甘地 何进忠 +1 位作者 牛洪斌 张忠平 《物探与化探》 CAS 2024年第5期1388-1399,共12页
甘肃省张掖盆地是国家现代农业示范区,也是1990s迄今唯一农业土壤调查与区域地球化学勘查相重合的地区。笔者搜集了1990s甘肃省物探队与化探队在张掖盆地及其周围山地采集的岩石、表土层深部土壤和水系沉积物的地球化学调查数据,按照拉... 甘肃省张掖盆地是国家现代农业示范区,也是1990s迄今唯一农业土壤调查与区域地球化学勘查相重合的地区。笔者搜集了1990s甘肃省物探队与化探队在张掖盆地及其周围山地采集的岩石、表土层深部土壤和水系沉积物的地球化学调查数据,按照拉依达法则和采样介质计算了元素在各个地质单元中的背景值;进而以重金属为主线,采用将区域表土层深部土壤背景值与中国土壤背景值和同时期耕作层土壤平均值作对比、第四系地层土壤背景值与区域土壤背景值作对比,以及将地球化学混合模型与地理学要素相结合的方法,探讨1990s张掖盆地表土层深部土壤重金属分布特征及其物质来源。相对中国土壤元素背景值,研究区表土层深部土壤富集Cu和Cd,贫Zn;与同时期耕作层土壤相比,Cr显著富集,Cu、Zn、Pb和As显著贫化。重金属Zn、Cd和As主要源于北祁连;Pb来源于龙首山;Hg和Cr可能主要与人类活动有关;表土层深部土壤中的H3潜在生态风险指数异常是西北风和东南风共同作用的结果。重金属在表土层深部土壤中的富集程度与人类活动强度正相关,与新构造运动强度负相关。本次研究为探讨该区区域土壤环境演化提供了科学数据。 展开更多
关键词 土壤 表土层深部土壤 重金属 物质来源 张掖盆地 甘肃
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Determination of Optimum Growing Degree-Days (GDD) Range Before Winter for Wheat Cultivars with Different Growth Characteristics in North China Plain 被引量:9
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作者 LI Qiao-yun YIN Jun +5 位作者 LIU Wan-dai ZHOU Su-mei LI Lei niu Ji-shan niu hong-bin MA Ying 《Journal of Integrative Agriculture》 SCIE CSCD 2012年第3期405-415,共11页
To provide base for adjusting the sowing date,achieving the yield potential of wheat cultivars with different growth characteristics,and improving the utilization rate of natural resource in the North China Plain (NC... To provide base for adjusting the sowing date,achieving the yield potential of wheat cultivars with different growth characteristics,and improving the utilization rate of natural resource in the North China Plain (NCP),a 4-yr field experiment of growing degree-days (GDD) before winter (realized through different sowing dates) with three wheat (Triticum aestivum L.) cultivars of each type of semi-winterness and weak springness was carried out at 20 test experimental sites (32°4’N36°1’N) of Henan Province in the NCP.The results showed that:(i) yield of semi-winterness wheat was significantly higher than weak springness wheat (P〈0.01);(ii) there was a quadratic regression between the yield and GDD before winter.According to the regression equation,the optimum GDD range with high yield of semi-winterness and weak springness wheats was 750-770 and 570-590°C d,respectively;(iii) under the optimum GDD condition,the foliar age on the main stem of semi-winterness and weak springness wheats was 7.67-7.91 and 6.36-6.86 leaves,respectively,calculated by the linear regression equation between foliar age and GDD before winter;(iv) both semi-winterness and weak springness wheats were in the double ridge stage of spike differentiation under the condition of the optimum GDD range,and at this time,the foliar age on the main stem of semi-winterness and weak springness wheats was about 7.80 and 6.07 leaves,respectively,which was consistent with the results calculated by the liner regression equation.Therefore,we could consider that the sowing date is appropriate if the foliar age is about 7.8 and 6.3 leaves for semi-winterness and weak springness wheats,respectively.According to the results of this study,choosing semi-winterness wheat and planting 710 d earlier would improve yield and natural resource utilization in NCP. 展开更多
关键词 WHEAT growing degree-days (GDD) yield foliar age
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深度学习联合地震反演助力深海储层参数预测 被引量:4
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作者 安鹏 高健祎 +2 位作者 曹丹平 牛洪彬 吴凡 《海洋工程装备与技术》 2019年第S01期255-260,共6页
弹性阻抗反演是主要的储层参数预测方法之一。入射角范围有限和低地震资料质量等原因,会导致密度反演的准确率较低。此外,纵横波速度比在速度峰值处的反演稳定性较差,也不能直接反演孔隙度等储层物性参数。目前通过常规的弹性阻抗反演... 弹性阻抗反演是主要的储层参数预测方法之一。入射角范围有限和低地震资料质量等原因,会导致密度反演的准确率较低。此外,纵横波速度比在速度峰值处的反演稳定性较差,也不能直接反演孔隙度等储层物性参数。目前通过常规的弹性阻抗反演等方法无法有效解决上述问题。本文将深度学习技术与弹性阻抗反演技术相结合,基于全连接深度神经网络建立起三个角度弹性阻抗与弹性、物性储层参数之间的非线性映射关系,测井数据的密度、纵横波速度比预测的均方根误差均降低10%以上。并以弹性阻抗搭建起测井、地震数据之间的桥梁,通过标准化等数据处理技术,最终得到密度、纵横波速度比和孔隙度的三维预测结果。 展开更多
关键词 深度学习 地震反演 深海勘探 储层参数预测
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