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宁镇山区不同森林土壤生物学特性的研究 总被引:24,自引:6,他引:18
对宁镇山区不同森林土壤微生物、土壤酶活性,营养元素的变化及凋落物的分解等生物学特性进行了探讨,结果表明,土壤微生物数量和6种土壤酶的生化活性在不同的季节的不同的林型土壤中均呈现出一定的变化规律,土壤中营养元素的含量随森林的生长周期而发生规律性的变化,并与土壤中微生物数量和土壤酶活性有显著的相关性,不同林地凋落物分解速率与其营养元素归还速率存在一定的时空差异,对次生栎林、毛竹林和杉木林土壤各生物学特性的比较表明,栎林土壤营养元素的含量最丰富,并具有较强的自肥调控能力,因此种植针阔混交林有利于防止针叶纯林的地力衰退现象。 相似文献
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福建柏和杉木人工林营养元素积累与分配 总被引:3,自引:0,他引:3
对福建三明33a生福建柏和杉木人工林群落营养元素积累和分配进行了研究,结果表明:福建柏和杉木人工林群落乔木层生物量分别为228.8thm-2和235.1thm-2,N、P、K、Ca和Mg等5种元素总积累量分别为1283kghm-2和1060kghm-2,乔木层和群落5种元素积累量的大小顺序均为:K>N>Ca>Mg>P,5种元素总积累量在乔木层各器官的分配量顺序分别为:干材>枝>根>干皮>叶>枯枝、干材>根>干皮>叶>枝>枯枝。福建柏的营养利用效率低于杉木。虽然两种人工林生态系统94%以上的营养元素储存在土壤中,但是土壤中植物容易利用的有效营养元素储量较低,其中有效P在土壤中的储量低于植物中的储量。福建柏和杉木人工林33 a生时乔木层5种营养元素总和的当年存留量分别为30.75kghm-2和16.53kghm-2。 相似文献
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杉木人工林土壤可溶性有机质及其与土壤养分的关系 总被引:28,自引:5,他引:23
通过在福建省来舟林场对不同栽植代数杉木人工林土壤可溶性有机碳(DOC)和氮(DON)及土壤养分的研究,其结果表明,随着杉木栽植代数的增加林地土壤DOC和DON含量逐渐下降,在0~10cm土层内第3代杉木林土壤DOC和DON含量分别是第1代杉木林的83.9%和87.1%、第2代杉木林的90.6%和96.9%,在10~20cm土层内第3代杉木林土壤DOC和DON含量分别是第1代杉木林的80.2%和81.5%、第2代杉木林的81.8%和90.0%。在不同林地和土层内土壤DOC含量之间的差异性达到了显著或极显著水平,而DON含量之间的差异性不显著。不同栽植代数杉木林土壤养分的变化趋势与DOM一致,随着杉木连栽,土壤养分含量呈下降趋势。在0~10cm土层内第3代杉木林土壤全氮、全钾、铵态氮和速效钾含量分别是第1代杉木林的83.1%、60.4%、68.1%和44.3%,是第2代杉木林的84.6%、68.5%、74.4%和58.7%;在10~20cm土层内第3代杉木林土壤全氮、全钾、铵态氮和速效钾含量分别是第1代杉木林的74.0%、53.4%、57.6%和54.6%,是第2代杉木林的94.8%、59.5%、74.3%和65.5%。经相关性分析,在各土层内土壤DOC和DON含量与土壤全氮、全钾、铵态氮和速效钾等土壤养分含量存在着不同程度的相关性。 相似文献
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不同代数杉木林养分积累和分布的比较研究 总被引:21,自引:3,他引:18
在全国杉木中心产区,选择不同栽植代数(1、2、3代)、不同年龄阶段(5、10、15、20年)、不同立地(14、16、18地位指数)的杉木人工林,进行不同栽植代数杉木林养分积累和分布的比较研究.结果表明,栽植代数对杉木林养分积累和分布有较大影响.随栽植代数增加,杉木林乔木层养分积累及养分利用效率均呈逐代递减趋势,表现为3代<2代<1代,而林下植被养分积累呈逐代增加趋势,2、3代杉木林乔木层养分积累分别比1代下降17.62%和36.28%,3代比2代下降22.65%,同时多代连栽杉木林养分利用效率下降,生产单位干物质所需养分增加,增加了杉木生长对林地肥力的压力,不利于林地肥力的维持,但有利于其林下植被的养分积累. 相似文献
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亚热带地区阔叶林与杉木林土壤活性有机质比较 总被引:2,自引:0,他引:2
通过对亚热带3个地区地带性阔叶林和杉木林土壤活性有机质的比较,分析森林类型变化及杉木连栽对土壤有机碳和养分含量的影响.结果表明:地带性阔叶林转变为杉木林后,土壤总有机碳含量下降27.8%~52.1%、腐殖酸碳下降32.2%~52.8%、胡敏酸下降36.4%~59.0%、富里酸下降29.7%~50.0%;杉木连栽也使土壤总有机碳和腐殖质含量下降.森林类型改变和杉木连栽对土壤活性有机质的影响更明显.杉木林取代阔叶林后,土壤微生物生物量碳、微生物生物量氮、可溶性有机碳和可溶性有机氮含量的最大降幅分别为61.8%、38.2%、43.3%和69.0%;与第1代杉木林相比,第2代杉木林土壤微生物生物量碳、微生物生物量氮、可溶性有机碳和可溶性有机氮含量的最大降幅分别为34.7%、29.3%、30.4%、18.4%.经相关性分析,除冷水浸提有机氮外,土壤活性有机质与养分含量之间具有密切的相关关系. 相似文献
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杉木人工林土壤微生物生物量碳氮特征及其与土壤养分的关系 总被引:15,自引:4,他引:11
研究了湖南会同红黄壤区杉木人工林和常绿阔叶林土壤微生物量和养分状况.结果表明,该区杉木人工林取代地带性常绿阔叶林和杉木连栽后,土壤微生物碳、氮和土壤养分含量下降,土壤严重退化.在0~10 cm土层内,常绿阔叶林土壤微生物碳和氮含量为800.5和84.5 mg·kg-1,分别是第1代杉木林的1.90和1.03倍、第2代杉木林的2.16和1.27倍;在10~20 cm土层内,常绿阔叶林土壤微生物碳和氮含量为475.4和63.3 mg·kg-1,分别是第1代杉木纯林的1.86、1.60倍和第2代杉木林的2.11和1.76倍.在0~10 cm 和10~20cm土层内,杉木人工林取代常绿阔叶林和杉木栽植代数增加后,土壤全氮、全钾、铵态氮和速效钾含量均明显降低,但差异并不显著.人工杉木林林分组成单一,其凋落物分解慢、归还养分数量少;炼山等造成的表土流失是杉木人工林土壤微生物量和养分库退化的重要原因.土壤微生物碳与土壤全氮、铵态氮、全钾和速效钾含量呈极显著的正相关,土壤微生物氮与土壤养分含量也达到极显著水平. 相似文献
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亚热带侵蚀红壤植被恢复后营养元素通量的变化 总被引:8,自引:1,他引:7
对亚热带花岗岩红壤强度侵蚀地采取种草促林(ER1)、植灌促林(ER2),栽阔促林(ER3)3种生态恢复措施近20a后生态系统的营养元素储量及通量进行了研究,并以强度侵蚀地(CK1)和村旁受保护的风水林(CK2)为对照。研究结果表明:强度侵蚀地生态系统储存在植被中的营养元素总量及流通量极小,植被营养元素库存量仅7.494kg/hm2,乔木层营养元素年吸收量0.505kg/hm2,年归还量0.141kg/hm2。生态恢复约20a后,植被养分库储量和通量显著增加,ER1、ER2和ER3植被的营养元素总储量分别是强度侵蚀地的22.2、99.5倍和62.3倍,乔木层营养元素年吸收量分别是强度侵蚀地的20.9、171.5倍和82.9倍,年归还量分别是强度侵蚀地的42.5、158.4倍和93.9倍,年存留量分别是强度侵蚀地的12.5、176.6倍和78.7倍。ER2的营养元素循环恢复程度最好,虽然其植被营养元素库储存量、吸收量和归还量仍低于同地带未遭侵蚀的马尾松林,但其营养元素的吸收量和存留量与CK2的已没有显著差异,生态系统已基本具有自我维持功能。而施肥、有效的水土保持工程措施、种植当地适生的固N树种、适当高的密度、加强植被管理等措施,均可能有利于营养元素循环功能的恢复。 相似文献
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通过八年杉木针阔混交林的综合定位研究,筛选出一种高生产力和生态协调的人工林一以8杉木2火力楠为优势的混交林。林分的蓄积量和乔木层贮存的能量分别比杉木纯林高13.7%和11.3%,杉木火力楠混交林提高了林分的光能利用率,改善了林内小气候;增加了林地有机质的含量;促进了土壤中有益微生物的繁衍和土壤理化性质的改良,提高了土壤肥力和蓄水保水能力;增强了林分对害虫自我抑制能力。 相似文献
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广西林朵林场栽针(杉)保阔混交造林的效果研究 总被引:4,自引:0,他引:4
广西林朵林场栽针(杉)保阀混交造林试验表明:19龄和30龄混交林林分总蓄积量分别为184.78和515.58m3hm(-2),比同龄杉木纯林的依次高23.0%和21.8%.混交林中主要树种杉木的树高、胸径和蓄积量随混交树种株数比例的增加而降低.混交林林地枯枝落叶层现存量平均为15.18thm(-2),N、P、K、Ca和Mg5种元素的积累量平均为422.22kghm(-2),分别比杉木纯林的高25.3%和32.33%.混交林林地土壤有机质、全氮、水解氮、有效磷和速效钾的平均含量以及孔隙度和持水量都高于杉木纯林. 相似文献
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Changes in nutrient cycling with age in a Cunninghamia lanceolata plantation forest北大核心CSCD 下载免费PDF全文
Aims The purpose of this study is to investigate the characteristics of nutrient cycling in Cunninghamia lanceolata plantations with different ages, and to provide scientific basis for the management of high-yield plantations in China. Methods In this study, we used the ecological data of the past 25 years in Hunan Huitong Ecological Station and analyzed the nutrient cycling characteristics of the C. lanceolata plantation forests with different ages according to the law of tree growth and the dynamics of nutrient uptake. Important findings For most nutrients, their concentrations ranked in order as leaf > twig > bark > root > stem for all C. lanceolata trees with any ages. When the tree age was less than 12 years, nutrient concentrations increased with age, while they decreased with age when the tree was more than 12 years old. The changes in average annual nutrient uptake with age showed two peaks. Nutrient return gradually increases with age. For the same age, the nutrient use efficiency followed the order of phosphorus (P) > potassium (K) > nitrogen (N) > magnesium (Mg) > calcium (Ca). After the stand was closed, the nutrient utilization efficiency increases with the growth and development of trees. The cycling intensity of Ca and Mg was greater than that of N and P at the same stand age. The changes in nutrient cycling intensity with age varying curve with stand age acted as parabolic curve. Utilization of N, P and K was longer than displayed a parabolic shape for all elements. The utilization time of each element got shorter with increasing stand age. These results suggested that the nutrient uptake in different growth stages was not only controlled by the quantity of biomass, but also affected by the difference in nutrient concentration between previous and current stages. The nutrient cycling processes were jointly controlled by the mechanisms of nutrient redistribution and storage in Cunninghamia lanceolata, during the growth and development stages, and the nutrient use efficiency during different growth stages. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved. 相似文献
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川东红池坝地区红三叶(Trifoliumpratense)和鸭茅(Dactylisglomerata)人工草地土壤和植物营养元素的含量特征如下:(1)土壤中的元素含量以铁、钾和镁较高,钠、钙、氮、锰和磷较低,硫、锌、硼、铜和钼微少;(2)从元素的富集特征来看,该区土壤中的钙、硫为重度淋溶元素,钾、磷、镁、锌、钠为中度淋溶元素,铁、铜属轻度淋溶元素,锰属富集元素;(3)根据元素的生物吸收系列,红三叶属氮-钙型植物,鸭茅属氮-钾-磷型植物。(4)两种牧草的生物吸收系数,均以钙、硫、磷较高,钠、铁较低,其余7种元素介于二者之间。 相似文献
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Panagiotis Michopoulos George Baloutsos Anastasios Economou Constantini Samara Nikolaos S. Thomaidis Theodoros Grigoratos 《Plant and Soil》2007,294(1-2):31-39
The nutrient cycling and foliar status for the elements Ca, Mg, K, N, P, S, Fe, Mn, Zn and Cu were investigated in an urban
forest of Aleppo pine (Pinus halepensis) in 2004 in Athens, Greece in order to draw conclusions on the productivity status and health of the ecosystem. The fluxes
of bulk and throughfall deposition were characterized by the high amounts of Ca, organic N and sulfate S. The magnitude of
the sulfate S fluxes indicated a polluted atmosphere. The nutrient enrichment in throughfall was appreciable for ammonium
N, P and Mn. The mineral soil formed the largest pool for all the elements followed by the forest floor, trunk wood and trunk
bark. The understory vegetation consisting of annual plants proved important for storing N, P and K. Compared to current year
needles of Aleppo pine in remote forests of Spain, the needles of the Aleppo pine trees in Athens had significantly higher
concentrations of Ca, N, P and Cu and significantly lower concentrations of Mg and Zn. The soil had a high concentration of
calcium carbonate and accordingly high pH values. When all inputs to the forest floor were taken into account, the mean residence
time of nutrients in the forest floor followed the order Fe > Mn > Cu > Ca > Mg > P > Zn > N > K > S. 相似文献
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Nutrient cycling within three Pinus sylvestris stands was studied in eastern Finland. The aim of the study was to determine annual fluxes and distribution of N, P, K, Ca, Mg, Zn, Fe, B, and Al in the research stands. Special emphasis was put on determining the importance of different fluxes, especially the internal cycle within the trees in satisfying the tree nutrient requirements for biomass production. The following nutrient fluxes were included, input; free precipitation and throughfall, output; percolation through soil profile, biological cycle; nutrient uptake from soil, retranslocation within trees, return to soil in litterfall, release by litter decomposition. The distribution of nutrients was determined in above- and belowground tree compartments, in ground and field vegetation, and in soil.The nitrogen use efficiencies were 181, 211 and 191 g of tree aboveground dry matter produced per g of N supplied by uptake and retranslocation in the sapling, pole stage and mature stands, respectively. Field vegetation was more efficient in nitrogen use than trees. Stand belowground/aboveground and fine root/coarse root biomass ratios decreased with tree age. With only slightly higher fine root biomass, almost three times more nitrogen had to be taken-up from soil for biomass production in the mature stand than in the sapling stand.The annual input-output balances of most nutrients were positive; throughfall contained more nutrients than was lost in mineral soil leachate. The sulphate flux contributed to the leaching of cations, especially magnesium, from soil in the mature stand.Retranslocation supplied 17–42% of the annual N, P and K requirements for tree aboveground biomass production. Precipitation and throughfall were important in transferring K and Mg, and also N in the sapling stand. Litterfall was an important pathway for N, Ca, Mg and micro nutrients, especially in the oldest stands. 相似文献