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N-cycle gene abundance determination of N mineralization rate following re-afforestation in the Loess Plateau of China

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Soil Ecology Letters 2024年第1期6卷 97-106页

作者： Yaping Zhao Yuqing Zhao Shuohong Zhang Yulin Xu Xinhui Han gaihe yang Chengjie Ren College of Agronomy Northwest A&F UniversityYangling 712100China Shaanxi Engineering Research Center of Circular Agriculture College of AgronomyNorthwest A&F UniversityYangling 712100China

Afforestation effectively improved soil microbial communities and significantly increased soil nitro-gen mineralization rate(Rm).Soil microorganisms drive Rm by regulating soil N-cycling *** nitrification genes had a major effect on soil Rm than denitrification genes after *** the function of forest ecosystems requires an understanding of the mechanism of soil nitrogen ***,it remains unclear how soil N-cycling genes drive soil nitrogen mineralization during *** this study,we collected soil samples from a chrono-sequence of 14,20,30,and 45 years of Robinia pseudoacacia L.(RP14,RP20,RP30,and RP45)with a sloped farmland(FL)as a *** metagenomic sequencing analysis,we found significant changes in the diversity and composition of soil microbial communities involved in N-cycling along the afforestation time series,with afforestation effectively increasing the diversity(both alpha and beta diversity)of soil microbial *** conducted indoor culture experiments and analyzed correlations,which revealed a significant increase in both soil nitrification rate(Rn)and soil nitrogen mineralization rate(Rm)with increasing stand ***,we found a strong correlation between soil Rm and soil microbial diversity(both alpha and beta diversity)and with the abundance of soil N-cycling *** least squares path modeling(PLS-PM)analysis showed that nitrification genes(narH,narY,nxrB,narG,narZ,nxrA,hao,pmoC-amoC)and denitrification genes(norB,nosZ,nirK)had a greater direct effect on soil Rm compared to their effect on soil microbial *** results reveal the relationships between soil nitrogen mineralization rate and soil microbial communities and between the mineralization rate and functional genes involved in N-cycling,in the context of Robinia pseudoacacia *** on the Loess *** study enriches the understanding of the effects of microorganisms on soil nitrogen mineraliza

关键词： afforestation soil N mineralization rate denitrification genes nitrification genes the Loess Plateau

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汾河流域土地利用景观格局演变及其驱动因素探究

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西北农林科技大学学报（自然科学版） 2024年第6期52卷 83-94页

作者：杨珺李豪马青冯永忠杨改河周琳慧田昱辉太原师范学院经济与管理学院山西晋中030619 西北农林科技大学农学院陕西杨凌712100 西北农林科技大学人文社会发展学院陕西杨凌712100

【目的】分析汾河流域临汾段土地利用面积变化及景观格局演变特征,掌握影响土地利用变化的驱动因素,旨在为汾河流域可持续发展以及生态环境保护提供参考。【方法】以汾河流域中游临汾市为研究区,基于1990-2020年遥感、气象、社会经济等... 详细信息

【目的】分析汾河流域临汾段土地利用面积变化及景观格局演变特征,掌握影响土地利用变化的驱动因素,旨在为汾河流域可持续发展以及生态环境保护提供参考。【方法】以汾河流域中游临汾市为研究区,基于1990-2020年遥感、气象、社会经济等数据,计算该地区的土地利用程度指数、土地利用动态度、土地利用转移矩阵、景观格局指数(类型级别和景观级别),探讨近30年临汾市土地利用面积变化特征及景观格局的变化趋势,利用主成分分析方法筛选影响临汾市土地利用变化的主要驱动因素。【结果】从土地利用结构来看,临汾市土地利用类型以耕地为主,草地和林地次之。从土地面积变化来看,1990-2020年,各土地类型的面积变化量绝对值由大到小依次为建设用地>草地>耕地>林地>水域>未利用地,其中建设用地、林地及水域面积均增长,其余土地类型面积均减少;土地利用类型转移以耕地转为建设用地和草地以及草地转为耕地和林地为主。景观类型级别方面,耕地、林地和草地的最大斑块指数(LPI)、景观形状指数(LSI)、斑块平均大小(AREA_MN)和斑块结合度(COHESION)均较高;景观级别方面,随着时间的延长,斑块数量(NP)、斑块密度(PD)、香农多样性指数(SHDI)和香农均匀度指数(SHEI)总体均增加,边缘面积分维指数(PAFRAC)和蔓延度指数(CONTAG)均减少。主成分分析结果表明,社会经济因素、产业结构因素和自然因素是临汾市土地利用面积变化最主要的驱动因素。【结论】1990-2020年,临汾市的土地利用面积与景观格局发生了明显变化,探明了影响临汾市土地利用面积变化的主要驱动因素,其中建设用地、草地、林地和耕地受各驱动因素的影响较明显。

关键词：土地利用转移矩阵景观格局驱动因素汾河流域

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Seeking sustainable solutions for human food systems

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Geography and Sustainability 2023年第3期4卷 183-187页

作者： Zhiyuan Zhu Jiajia Duan Zhenzhong Dai Yongzhong Feng gaihe yang College of Agronomy Northwest A&F UniversityYangling 712100China College of Rural Revitalization Northwest A&F UniversityYangling 712100China

Sustainable food system development is the cornerstone of global human survival and *** research briefly analyzes the challenges facing the current food system,summarizes the directions of food system trans-formation,expounds the role of geography in the transformation of food system,and discusses the future paths to promote the sustainable development of food *** main conclusions are as follows:1)The interaction of factors such as regional conflicts,climate change,slowdown in development,raging epidemics,and resource and environmental constraints pose multiple challenges to the global food system.2)The food system should be high-quality,efficient,nutritious and healthy,green and low-carbon,inclusive and inclusive transformation.3)Geography can provide solutions for the transformation of food systems.4)The transformation paths of the food system includes:establishing a global food system with benefit sharing,cleaner production,and fair participation,improving the innovation capability of the food system,and establishing an effective organizational guarantee system.

关键词： Food systems Sustainable development Solutions

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Effect of competition on spatial patterns of oak forests on the Chinese Loess Plateau

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Journal of Arid Land 2017年第1期9卷 122-131页

作者： KANG Di DENG Jian QIN Xiaowei HAO Fei GUO Shujuan HAN Xinhui yang gaihe College of Forestry Northwest A&F University Yangling 712100 China The Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province Yangling 712100 China College of Agronomy Northwest A&F University Yangling 712100 China Spice and Beverage Institute Research Chinese Academy of Tropical Agricultural Sciences Wanning 730070 China Yunnan Baiyao Group CO. LTD Kunming 650500 China

Reforestation or natural forest regeneration is an alternative measure for controlling soil erosion in degraded land on the Chinese Loess Plateau（CLP）. However, our understanding of the temporal dynamics and the spatial patterns of forest regeneration remains inadequate. Two oak forests at different development stages were investigated to determine the spatial patterns of competitions（intraspecies and interspecies） during different successional stages. The intraspecies and interspecies spatial relationships among different tree diameters at breast height were analyzed at multiple scales by Kriging interpolation method and univariate and bivariate O-ring statistics. Our analytical results indicated that self-correlation and competition intensity were relatively high between oak and pine trees in the early development stage of oak forests due to their clumped distributions of heavy seeds. Birch trees had a lower competition in comparison to oak trees although birch was the dominant species. Therefore, asymmetric competition of oak trees was most likely to have led to their edge dispersal and their success in replacing the pioneer species. Asymmetric competition means that larger individuals obtained a disproportionately large share of the resources and suppressed the growth of smaller individuals. Kriging interpolation analysis showed a tendency towards homogenization caused by interspecies competition during the succession of oak forests. Our results demonstrated that the competition was the driving factor in the spatial distribution of oak forests on the CLP.

关键词： arid and semi-arid region forest regeneration competition spatial pattern oak forests

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Responses of plant community to the linkages in plant-soil C:N:P stoichiometry during secondary succession of abandoned farmlands,China

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Journal of Arid Land 2020年第2期12卷 215-226页

作者： LIU Weichao FU Shuyue YAN Shengji REN Chengjie WU Shaojun DENG Jian LI Boyong HAN Xinhui yang gaihe College of Agronomy Northwest A&F UniversityYangling 712100China Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province Yangling 712100China School of Life Science Yan'an UniversityYan'an 716000China

Succession is one of the central themes of ecology;however,the relationship between aboveground plant communities and underground soils during secondary succession remains *** this study,we investigated the composition of plant community,plant-soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0,10,20,30,40 and 50 a in China,*** showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 *** organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a,but both were significantly higher than those of control farmland(31.21%-139.10%and 24.24%-121.21%,respectively).Moreover,C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands,explaining 35.70%of the total ***,soil C:N ratio was significantly and positively related with the Shannon-Wiener *** study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them.

关键词： C:N ratio soil nutrient plant community restoration loess hilly region

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黄土高原次生林演替对团聚体有机碳含量及化学稳定性的影响

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生态学报 2024年第5期44卷 1940-1950页

作者：刘颖异刘涵宇张琦李向阳刘剑剑刘伟超王兴任成杰杨改河韩新辉西北农林科技大学农学院杨凌712100 陕西省循环农业工程技术研究中心杨凌712100

次生林演替过程中土壤团聚体有机碳的积累机制和化学稳定性研究较少。为探明次生林演替对土壤团聚体有机碳含量及其化学组成稳定性的影响,选取黄土高原次生白桦林(演替初期),山杨辽东栎混交林(演替中期)和辽东栎林(演替后期)为研究对象... 详细信息

次生林演替过程中土壤团聚体有机碳的积累机制和化学稳定性研究较少。为探明次生林演替对土壤团聚体有机碳含量及其化学组成稳定性的影响,选取黄土高原次生白桦林(演替初期),山杨辽东栎混交林(演替中期)和辽东栎林(演替后期)为研究对象,分析演替过程中不同粒径土壤团聚体有机碳含量变化特征。采用傅里叶红外光谱技术(FTRI)测定活性(AC)和非活性(IC)有机碳化学组成,以(IC/AC)作为有机碳化学组成稳定性指标,并分析其影响因素。结果表明:次生林演替过程中土壤团聚体有机碳含量表现出逐渐增加的趋势且各群落间差异显著(P<0.05),以演替后期的中等粒径团聚体为最高(37.63 g/kg)。土壤团聚体AC中多糖体有机碳含量最高(55.87%),而IC中芳香族有机碳含量最高(94.45%),演替过程中IC与AC总体变化趋势均呈现先降后增。IC/AC随着演替的进行呈先降低后升高的趋势,其中演替后期微团聚体有机碳化学组成稳定性最强达到了3.95。微团聚体含量(WM)与土壤全氮、全磷、全钾一起,显著促进了团聚体有机碳化学组成稳定性(P<0.05)。综上,次生林演替有利于促进土壤团聚体有机碳的积累以及有机碳化学稳定,其中微团聚体起到了关键性作用。

关键词：土壤团聚体有机碳化学组成次生林演替傅里叶红外光谱技术(FTRI) 黄土高原

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Effect of Soil C,N and P Stoichiometry on Soil Organic C Fractions After Afforestation

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Pedosphere 2017年第4期27卷 705-713页

作者： ZHAO Fazhu ZHANG Lu SUN Jiao REN Chengjie HAN Xinhui yang gaihe PANG Guowei BAI Hongying WANG Jun College of Urban and Environmental Sciences Northwest University Shaanxi Land Construction Group Shaanxi LCG Land Project Technology InstituteKey Laboratory of Degraded and Unused Land Consolidation Engineeringthe Ministry of Land and Resources of China Institute of Agricultural Resources and Environment Ningxia Academy of Agriculture and Forestry Sciences College of Agronomy Northwest A&F University

Afforestation is recognized as an important driving force for soil organic C(SOC) dynamics and soil element *** evaluate the relationships between soil C:N:P stoichiometry and SOC fractions,soil C:N:P stoichiometry distributions at 0–200 cm soil depths were analyzed and the contents of SOC fractions were evaluated in 9 typical land-use systems on the Loess Plateau of *** contents of light fraction organic C,particulate organic C(>53,53–2 000,and>2 000 μm),labile organic C,microbial biomass C,and dissolved organic C decreased with increasing soil depth and were higher in afforested soil than in slope cropland *** with the slope cropland,different vegetation types influenced soil C:N,C:P,and N:P ratios,especially when C:P and N:P ratios were significantly higher(P<0.05).Moreover,SOC fractions at the 0–10 and 10–40 cm depths were particularly affected by soil C:P ratio,whereas those at the 40–100 and 100–200 cm soil depths were significantly affected(P<0.05) by soil N:P *** results indicate that changes in SOC fractions are largely driven by soil C:P and N:P ratios at different soil depths after afforestation.

关键词： dissolved organic C, labile organic C, light fraction organic C, microbial biomass C, particulate organic C

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Accumulative Effect of Soil Organic Carbon and Nitrogen in Water-Stable Aggregates and Soil Stability Characteristics of Robinia pseudoacacia Plantation in the Loess Hilly-Gully Region

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Open Journal of Soil Science 2016年第12期6卷 204-221页

作者： Jiao Sun Junfeng Li gaihe yang Wenfang Hao College of Life Science Northwest Agriculture and Forest University Yangling Shaanxi China Institute of Agricultural Resources and Environment Ningxia Academy of Agriculture and Forestry Sciences Yinchuan Ningxia China College of Water Conservancy and Architectural Engineering Shihezi University Shihezi Xinjiang China College of Agriculture Northwest Agriculture and Forest University Yangling Shaanxi China

Soil water-stable aggregates (WSAs) are the basic unit of soil constitution and can contribute to remaining the stable soil constitution. The objective of this study was to clarify the distribution and stability of WSAs and the soil organic carbon (SOC), the total nitrogen (TN), and the total phosphorus (TP) concentrations in 0 - 20 cm and 20 - 40 cm soil layers under the different ages of Robinia pseudoacacia plantations. The 20, 25, 40, and 50 years-old Robinia pseudoacacia plantations were selected. Stepwise regression analysis showed that >5 mm and 1 - 2 mm WSAs, SOC concentration in 2 - 5 mm WSAs, and TN and TP concentrations in < 0.25 mm WSAs were dominant independent variables affecting aggregate stability and that SOC in 0.25 - 0.5 mm WSAs, TN in <0.25 mm and 1 - 2 mm WSAs and TP in 2 - 5 mm WSAs were dominant independent variables affecting SOC, TN, and TP concentrations in bulk soils.

关键词： Soil Water-Stable Aggregate Robinia pseudoacacia Plantation Soil Nutrient

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延安市退耕过程植被覆盖度变化及其影响因子分析

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农业机械学报 2015年第8期46卷 272-280页

作者：朱会利杨改河韩磊西北农林科技大学林学院陕西杨凌712100 长安大学地质工程与测绘学院西安710054 长安大学地球科学与资源学院西安710054

基于像元二分模型,利用2000—2012年的MODIS植被指数资料分析了延安市退耕还林过程中植被覆盖度的变化及影响因子。研究结果表明,2000—2012年延安市植被覆盖度呈极显著增长趋势,由43.4%增加到66.8%,增幅达53.9%。延安市各区县的植被覆... 详细信息

基于像元二分模型,利用2000—2012年的MODIS植被指数资料分析了延安市退耕还林过程中植被覆盖度的变化及影响因子。研究结果表明,2000—2012年延安市植被覆盖度呈极显著增长趋势,由43.4%增加到66.8%,增幅达53.9%。延安市各区县的植被覆盖度在波动中均呈现增长趋势,增幅较大的为子长县、延川县和延长县,分别为212.8%、134.2%和127.8%,增幅较小的为黄龙县和黄陵县,分别为28.9%和29.2%。植被覆盖状况总体呈现稳定的改善状态,改善极显著和显著的县区面积占研究区总面积的74.04%,改善不明显的县区面积占研究区总面积的23.91%,退化显著和极显著的县区面积仅占研究区总面积的2.05%。研究区高覆盖度植被和中覆盖度植被面积增加,低覆盖度植被面积减少,退耕初期由大到小表现为:低覆盖度植被面积、高覆盖度植被面积、中覆盖度植被面积,退耕后期由大到小分别为:高覆盖度植被面积、中覆盖度植被面积、低覆盖度植被面积,表明该区域植被覆盖度结构转好。植被覆盖度变化受6—8月份的降水量影响不大,相关性较低,但和累计退耕还林面积有较强的正相关性。说明退耕还林工程的实施增加了地面植被覆盖度,改善了植被覆盖的结构,植物应对环境变化的能力越来越强,降水量的年际变化对植被覆盖度造成的影响越来越小。

关键词：植被覆盖度遥感退耕还林动态变化影响因子

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冬小麦F_2主要性状遗传进度的分析

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西北农林科技大学学报（自然科学版） 1989年第3期23卷 38-44页

作者：杨改河西北农业大学农学系

本文通过对F_2主要性状遗传进度、相关遗传进度、选择指数的估算分析,得出在有些组合中可对单株粒重进行直接选择,一些组合可用株高、抽穗期、百粒重、每穗粒数对单株粒重进行间接选择,其它产量组成因素以直接选择为佳。提出可用Y=-3.49... 详细信息

本文通过对F_2主要性状遗传进度、相关遗传进度、选择指数的估算分析,得出在有些组合中可对单株粒重进行直接选择,一些组合可用株高、抽穗期、百粒重、每穗粒数对单株粒重进行间接选择,其它产量组成因素以直接选择为佳。提出可用Y=-3.4923X-11.7590X+65.3411X+0.8909X(株高+抽穗期+百粒重+每穗粒数)指数式进行组合评定和单株选择。

关键词：小麦育种数量遗传遗传进度育种方法

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