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1.
黄淮海平原地区夏玉米农田土壤呼吸的动态研究 总被引：30，自引：1，他引：30
本文通过对黄淮海平原地区玉米生长季土壤呼吸的测定表明：该地区土壤呼吸日变化呈现单峰曲线；土壤呼吸季节变化大体呈现随温度变化的趋势，最大值出现在8月10日左右；土壤呼吸受5cm地温的影响最大，达到极显著水平。施有机肥对土壤呼吸影响较大，氮磷配施也增加了土壤呼吸量，免耕比耕翻有较少的土壤呼吸量。运用DNDC模型模拟土壤呼吸变化趋势和土壤呼吸变化通量均与田间实测的比较接近，可以用来模拟分析黄淮海平原地区农业土壤碳氮的循环。 相似文献
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不同施肥处理对黑土土壤呼吸的影响 总被引：23，自引：0，他引：23
基于中国科学院海伦生态实验站的长期定位试验,采用静态箱式法研究了玉米生长期间不同施肥处理对黑土土壤呼吸的影响。结果表明,在玉米生长期间,土壤呼吸速率表现出明显的季节性变化,分别在出苗后23、37、50、63、87、110 d出现峰值,其中最大峰值出现在出苗后第87天,其后土壤呼吸速率呈下降趋势,直到玉米收获,而根际呼吸速率的季节性变化规律与土壤呼吸相似,土体呼吸速率则主要受气温变化影响;玉米生长显著影响土壤呼吸,土壤呼吸速率的变化基本与玉米生长规律相一致,随生长而增加,随衰老而减小;施肥对土壤呼吸速率、根际呼吸速率有明显的影响,但对土体呼吸速率影响较小,从整个玉米生长期来看,NPKOM处理的土壤呼吸速率和根际呼吸速率最高,其中NPKOM处理土壤呼吸速率为C 27.5~474 mg m-2h-1,NPK处理和NP处理变化范围相近,分别为C 25.9~339 mg m-2h-1和C 29.5~358 mg m-2h-1,NK处理与CK处理变化范围分别为C 28.4~208 mg m-2h-1和C 22.1~184 mg m-2h-1;施肥对土壤呼吸量和根际呼吸量有显著的影响,表现为NPKOM>NPK>NP>CK>NK;在整个玉米生育期中,土壤呼吸累积量在拔节孕穗期和乳熟期出现两个峰值,表现为双峰曲线的变化规律,而土体呼吸累积量只在拔节孕穗期出现峰值,呈抛物线型,根际呼吸量在苗期最低,乳熟期最高,乳熟期后,根际呼吸量下降。 相似文献
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通过对黄土丘陵区油松、沙棘人工林自然组(含凋落物)和去凋组(不含凋落物)土壤呼吸、5cm土壤温度和含水量的监测,研究地表凋落物对土壤呼吸的影响。在两种林分内分别设置20m×20m样地,样地内随机设置5个观测点,于2015年6月到2016年5月使用LI-8100系统进行监测。结果表明:(1)自然组油松林和沙棘林土壤呼吸季节动态及日动态均表现为单峰型变化曲线,沙棘土壤呼吸年均值[2.10μmol/(m~2·s)]显著高于油松[1.56μmol/(m~2·s),p0.05];去除凋落物后,两种林分土壤呼吸与自然组具有相似的季节及日动态特征,但土壤呼吸年均值不存在显著性差异。(2)沙棘林自然组土壤呼吸年均值显著高于去凋组[1.58μmol/(m~2·s),p0.05],凋落物呼吸对土壤总呼吸的贡献率为15.81%;油松林自然组与去凋组土壤呼吸年均值差异不显著,凋落物呼吸对土壤总呼吸的贡献率仅为1.61%。(3)自然组和去凋组中油松、沙棘林土壤呼吸与温度均存在显著指数关系(p0.05),与含水量则存在显著线性负相关关系(p0.05);两组处理土壤温度和含水量对土壤呼吸的单独解释量均较低(0.05%~37.82%),土壤呼吸主要受到温度和含水量共同作用的影响(8.01%~66.44%)。地表凋落物显著提高了沙棘林土壤呼吸的Q10和土壤呼吸量,但仅显著提高了油松林的Q10,对土壤呼吸量并未显著增加。油松林作为黄土丘陵区水土保持及生态恢复的造林树种更有利于该地区林地碳汇功能的提升。 相似文献
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黄土丘陵区土壤基础呼吸对草地植被恢复的响应及其影响因素 总被引：6，自引：0，他引：6
为探讨黄土丘陵区草地植被自然恢复过程中土壤微生物活性的变化特征及其影响因素, 采用"时空互代"法采集宁夏云雾山自然保护区8个不同植被恢复年限的春、夏两季0～20 cm和20～40 cm的土样, 用室内密闭静态培养-碱液吸收法测定了新鲜和风干土样的基础呼吸.结果表明: 土壤基础呼吸随植被恢复年限增加呈增加趋势, 土壤呼吸强度和累积呼吸量都表现为植被恢复73年和78年较高, 而耕地和植被恢复3年最低.采样季节对呼吸强度测定有较大影响, 春季土样能更好地反映土壤微生物活性的变化.风干土样可以通过预培养后测定土壤的呼吸作用, 且能更加稳定地反映不同土壤之间的差异.在测定土壤基础呼吸时, 利用 1 d或3 d的培养平均值能更稳定地表现不同土壤的特性.累积呼吸量可较呼吸强度更直观地反映不同土壤的微生物活性.土壤有机质和全氮含量与土壤呼吸强度密切相关. 相似文献
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通过对经不同途径形成的新鲜蚓粪和老化蚓粪进行35d的CO2呼吸动态测定,比较两种蚓粪有机碳呼吸的差异,从而加深对蚯蚓影响土壤有机碳库周转的理解。新鲜蚓粪由过1mm筛的潮土与红壤在不同植物残体施用下经蚯蚓(Metaphire guillelmi)48h作用形成,湿润老化的蚓粪也由上述两种土壤经同种蚯蚓30d培养生成。结果表明:新鲜蚓粪中有机碳的呼吸量均大于相应土壤中的,特别是施用玉米残体形成的蚓粪;老化蚓粪中,除红壤不施植物残体形成的老化蚓粪的呼吸量低于相应土壤外,其它老化蚓粪的呼吸量均大于相应土壤的。蚓粪的呼吸与土壤质地、有机碳含量、植物残体及蚓粪老化程度等有关。 相似文献
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农田土壤呼吸特征及根呼吸贡献的模拟分析 总被引：17，自引：8，他引：17
采用静态箱法研究了黄淮海平原典型农田土壤CO2排放通量的日变化、季节变化特征,分析了土壤温度、水分对土壤呼吸的影响;并利用反硝化一分解(DNDC)模型定量化研究了根呼吸对土壤总呼吸的贡献.结果表明,在作物生长季节内棉花地、休闲地和冬小麦/夏玉米地土壤CO2排放均表现出明显的季节变化规律.土壤CO2排放季节变化的总体趋势是夏季高、其他季节低,与对应气温的动态变化基本一致.冬小麦/夏玉米地土壤CO2排放通量高峰值为2324 mg·m-2·h-1,棉花地为1111.9 mg·m-2·h-,休闲地为436.07 mg·m-2·h-1.土壤CO2季节性排放受温度的影响最大,其中与5 cm地温的相关性最好,与土壤湿度的相关性不太明显.同一种种植模式施氮量高的处理CO2平均排放通量大于低的处理.同时根据DNDC模型估算,玉米根际呼吸对土壤呼吸的贡献最大,为91%～95%,棉花和冬小麦根际呼吸比例分别约为70%和80%.施氮不仅影响土壤微生物的呼吸而且还影响到根系呼吸. 相似文献
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不同秸秆还田方式对黄土高原坡耕地土壤呼吸的影响 总被引：2，自引：0，他引：2
选取豫西黄土高原典型玉米坡耕地,设置常规耕作+秸秆不还田（CT）,常规耕作+秸秆还田（TSI）和常规耕作+秸秆覆盖（TSM）3种处理,采用LI-8100A土壤碳通量测定系统,研究非生长季不同秸秆还田方式对土壤呼吸时空变化的影响。结果表明:CT,TSI,TSM处理下土壤呼吸速率随时间变化趋势基本一致,变化范围分别为0.22～1.23,0.29～1.35,0.26～0.91 μmol/（m2·s）,在温度和水分较低时段3者差异不显著,在温度和水分较高的时段3种处理土壤呼吸差异显著,表现为TSI > CT > TSM。3种处理不同坡位土壤呼吸有明显差异,总体表现为坡下 > 坡中 > 坡上,TSM处理下土壤呼吸空间异质性明显低于其他两种处理;不同坡位土壤温度和水分呈现明显的差异性,表现为坡下 > 坡中 > 坡上,并随温度和水分的升高,空间差异性增大。不同处理下土壤呼吸与温度和水分都呈现出显著的线性相关关系（p < 0.01）。秸秆覆盖在非生长季能有效减少土壤呼吸量,而秸秆还田增加土壤呼吸量,因此秸秆覆盖从减少温室气体排放的角度是较合理的秸秆还田方式。 相似文献
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运用盆栽试验研究了玉米生长和施氮水平(N 150 mg kg-1和300 mg kg-1)对土壤呼吸的影响。结果表明种植玉米的土壤呼吸速率(C)的变化范围为19. 6 ~ 762. 1 mg m-2h-1,而裸土为4. 3 ~ 36mg m-2h-1。在玉米生长的条件下,苗期土壤呼吸最低,73%的土壤呼吸分配在拔节孕穗期和成熟期。玉米生长中各阶段根际呼吸对土壤呼吸的贡献在58%~98%,苗期最小。施氮对裸土呼吸速率无显著影响;在玉米生长的条件下,施用高氮的土壤呼吸比施用低氮高28%,且两种施氮水平下土壤呼吸的差异主要发生在生长中后期。玉米生长的条件下土壤呼吸与温度的相关性不显著,而裸土下土壤呼吸速率与气温、表土温度、5 cm土壤温度均呈极显著的相关性;裸土施用高氮下的土壤呼吸与温度的相关性大于低氮。总之,玉米生长和土壤施氮不仅影响土壤呼吸速率和呼吸量,也影响土壤呼吸在各生长阶段的分配,还影响到土壤呼吸与温度的关系。 相似文献
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有机物料对平邑甜茶实生苗根系呼吸强度的影响 总被引：21，自引：6，他引：21
研究了几种有机物料对一年生平邑甜茶实生苗吸收根、生长根、褐色木质根呼吸强度的影响。结果表明,不同有机物料对三类根呼吸强度提高的程度不同,夏季为鸡粪>羊粪>花生秧处理;秋季羊粪>鸡粪>花生秧处理。整株根系呼吸强度,夏季鸡粪、羊粪和花生秧处理分别比对照提高56%、31%和25%;秋季羊粪比鸡粪处理高19%。吸收根、生长根和褐色木质根呼吸强度差异显著,夏季吸收根呼吸强度是褐色木质根的2～3倍、秋季为2～2.4倍;生长根呼吸强度是褐色木质根的1.5～1.9倍、秋季为1.3～1.7倍。白色根(吸收根与生长根之和)与褐色木质根各自的总呼吸量占整株根系呼吸量比例随季节变化而不同,夏季白色根所占比例超过50%,秋季褐色木质根呼吸量所占比例达68%～80%,在整株根系呼吸量中占主导地位。 相似文献
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论述数字馆藏的产生、概念和特点,分析数字馆藏资源建设中存在的问题,探讨数字馆藏资源建设中应采取的策略。 相似文献
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Sycheva S. A. Pushkina P. R. Khokhlova O. S. Ukrainsky P. A. 《Eurasian Soil Science》2020,53(11):1521-1537
Eurasian Soil Science - Recent and Late Pleistocene soils of the central forest-steppe in the East European Plain have been studied. The main objective of the work is to reveal changes in the... 相似文献
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The alterations are studied which are produced in the content of mineral elements and organic fractions of sap with the increase in the osmotic pressure of the nutritive solution at levels of 2.0; 3.5 and 5.0 atm., obtained through the addition to the nutritive solution either of magnesium sulphate or PEG‐4000. Through the effect of the osmotic pressure, the transformations are modified of the nitrogen and mineral phosphorus at organic fractions experience a series of modifications which produce different values in the Nm%TSN and Pm%TSP ratios with respect to control. Through action of the specific effect of magnesium sulphate, the reducing sugars concentrations in sap having an important increase. 相似文献
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Changes in the taxonomic structure of actinomycetes in the rhizosphere of winter rye (Secale cereale L.) growing on acid soddy-podzolic soil were studied. During the first stages of ontogenesis of winter rye, the rhizosphere complex of mycelial prokaryotes was characterized by a relatively level generic structure (with respect to the indices of abundance and frequency of particular genera), low values of the species diversity, and low domination frequency of the species from the Streptomyces genus. The numbers and species diversity of the streptomycetes increased during the further growth of the winter rye, so that streptomycetes became a dominant group in the complex of the rhizosphere actinomycetes. According to the two-way ANOVA, the population density of the Micromonospora and the Streptosporangium genera in the rhizosphere was mainly dictated by the winter rye variety, whereas the population density of the streptomycetes depended on the particular stage of the winter rye development. The differences between the actinomycetal complexes characteristic of different varieties of winter rye at the early stages of its development was leveled by the end of the winter rye growth. 相似文献
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Yu. G. Chendev A. L. Aleksandrovskii O. S. Khokhlova M. I. Dergacheva A. N. Petin A. N. Golotvin V. A. Sarapulkin G. L. Zemtsov S. V. Uvarkin 《Eurasian Soil Science》2017,50(1):1-13
The Late Holocene stage of forest pedogenesis has been studied on the interfluves along river valleys in the forest-steppe zone of the Central Russian Upland. The development of gray forest soils from the former chernozems as a result of the Late Holocene advance of forest vegetation over steppes is discussed. It is argued that the climatic conditions of the Subatlantic period were unstable, so that multiple alternation of forest and steppe vegetation communities took place. This specified a complex character of soil evolution upon contrasting substitution of forest pedogenesis for steppe pedogenesis. On the interfluves near the natural drainage network (balkas, ravines, and steep slopes of river valleys), the climate-driven dynamics of forest and steppe vegetation with corresponding changes in the character of pedogenesis could take place during the entire Holocene, which is reflected in a lower thickness of humus profiles and deeper leaching of carbonates from chernozems of the Early Iron Age in comparison with their analogues formed under steppe cenoses in central parts of the interfluves. Two variants of the evolution of gray forest soils can be suggested: the pulsating evolution typical of balkas and interfluves near river valleys and the continuous progressive evolution typical of automorphic (plakor) positions in central parts of the interfluves. 相似文献
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Accumulation of chemical elements in the raised peatbogs of the subtaiga Trans-Urals in the Holocene
The results of studying the variability of the geochemical parameters of the layers of the Sartamskii upland peatbog in the south of Tyumen oblast based on the radiocarbon time scale are given. Four basic types of peat and stages of peat deposits formation in the Holocene are distinguished: the organomineral layer of the sediments in a paleolake (up to 5065 ± 60 years ago), the low moor layer (4300–4900 years ago), the transitional layer (3100–4300 years ago), and the high moor peat (250–3100 years ago). The upper peat layer (last 200–300 years) significantly differs from its main portion; in particular, it is characterized by an increased ash content and the accumulation of a number of elements. The relationship between the various characteristics of the deposit is analyzed using principal component analysis, and the conditions of the formation of the peat deposit in different time periods are estimated, including the climatic conditions (in relative units). The anthropogenic signal of the accumulation of some elements in wetland systems is identified. 相似文献
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产地溯源是保护农产品品牌及地区特色产品、防止欺诈、保护消费者权益的有效保障。稳定同位素指纹分析是用于食品产地溯源的有效技术之一,具有高效、准确、可靠的特点。本文系统分析了近5年来,稳定同位素指纹分析技术在植物源性初级农产品、加工农产品溯源中的应用以及稳定同位素在食品加工过程中分馏变化的研究进展。在此基础上,展望了今后稳定同位素在植物源性农产品产地溯源中的研究重点和发展方向。 相似文献
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Specific structural and dynamic parameters of communities from various ecological and trophic groups of microorganisms and algae in the litter of artificial tree stands were studied using the example of the Staro-Berdyansky Forest in the steppe zone of Ukraine. The composition of the communities was shown to vary by seasons and depend on the forest-forming woody species. In spring, in all the litters, the maximal number of actinomycetes and aminotrophs was recorded; in the leaf litter, the number of phosphate-mobilizing organisms was also the largest. In summer, the development of cellulolytic organisms, ammonifiers, and nitrogen-fixers was intensified; in autumn, the number of micromycetes and oligotrophic organisms decreased. The composition of dominants, the species richness of algae and their abundance also varied by seasons. Representatives of the Chlorophyta division predominated. The highest species richness of algae was characteristic of the spring litter samples, and their number, for the spring and autumn ones. The positive correlation was established between the numbers of micromycetes and oligotrophs, micromycetes and algae. The negative correlation was found between the numbers of micromycetes and actinomycetes, cellulose-decompose bacteria and algae in the litters. 相似文献