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杉木毛竹混交林土壤理化性状研究 总被引：3，自引：1，他引：2
对尤溪县梧园村毛竹纯林改造成毛竹混交林的土壤理化性质进行分析,结果表明:在0～20 cm土层中,杉竹混交林土壤的容重低于毛竹纯林,总孔隙度、非毛管孔隙度、毛管孔隙度、通气度、孔隙度比都比毛竹纯林增加,杉竹混交林土壤的毛管持水量、最小持水量增加,土壤的保水能力增强;杉竹混交林土壤的有机质、全氮、全磷、全钾、水解性氮、速效磷和速效钾含量比毛竹纯林增加,土壤的酸性得到改善。说明混交有利于改善土壤的通气透水能力,发挥林分水源涵养功能,有利于增加土壤养分及养分的有效化,从而有利于植物的生长。 相似文献
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毛竹杉木混交造林对土壤养分及林木生长的影响 总被引：3，自引：0，他引：3
对福建省宁化县方田乡泗坑村营造的7年生杉木毛竹混交林和杉木、毛竹纯林的林下土壤养分及林木生长量进行调查分析,结果表明:毛竹杉木混交林的土壤有机质、全氮、全磷、全钾、水解氮、速效磷、速效钾的含量均比毛竹纯林和杉木纯林高,毛竹杉木混交林中毛竹、杉木的平均胸径、平均高、枝下高、冠幅、单株材积生长量均比毛竹、杉木纯林高。表明,毛竹、杉木混交造林改善了土壤养分,促进林分的生长。 相似文献
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秦岭山区油松纯林与松栎混交林下土壤养分状况分析 总被引：1，自引：0，他引：1
对秦岭山区油松纯林与松栎混交林下土壤养分状况进行研究,结果表明:纯林与混交林都有富积养分的效应,但两者对养分的影响有明显差异。混交林在土壤表层、根际及土壤剖面上土壤的有机质、全氮、速效氮含量明显高于纯林,而速效磷的含量低于油松纯林。在0~20cm土层,土壤有机质、全氮、速效氮、全磷、速效磷的含量,混交林比纯林分别增加83.8%、40.6%、127.6%、7.3%、44.4%。由于混交林能积累较多的有机质,因而更有利于改善土壤肥力。 相似文献
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杉木多代连栽林地营造杉阔混交林后的土壤肥力变化 总被引：3，自引：0，他引：3
在３代杉木采伐迹地上营造彬阔混交林的林地土壤孔隙状况,水分状况和养分状况优于继续营造杉林纯林,且以表层土壤尤为明显。土壤表层容重杉阔混交林的比杉木纯林减少６．８７％;土壤贮水量比杉森纯林增加３．６１％;土壤表层非毛管孔隙度比杉木要纯林高３．３１％;土壤表层的有机质、全氮、水解性氮、速效性磷和速铲性外界一分别比杉木纯林增加１８．９８％、２４．７３％、１８．７５％￣１６．６０％、１０．８７％和５．７０ 相似文献
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杉木火力楠混交林与杉木纯林土壤碳氮库研究 总被引：4，自引：0，他引：4
通过实地调查取样和室内C、N元素分析仪的测定,比较了杉木纯林与杉木火力楠混交林的土壤碳库及垂直分布差异,结果显示:混交林的土壤有机碳含量比纯林高,其有机碳贮量比杉木纯林大17.57%,主要差异在枯枝落叶层,分别为3.620 t.hm-2和12.610 t.hm-2。有机碳富集指数20~40 cm差异最大,混交林富集指数是纯林的1.18倍。混交林土壤有机碳贮量(79.460 t.hm-2)大于杉木纯林(67.583 t.hm-2),且均以表层(0~20 cm)碳贮量为主。混交林的全氮含量高于纯林,C/N则低于纯林。这些差异主要是由不同林分凋落物数量和性质上的差异引起的。杉木和火力楠混交林比杉木纯林更有利于碳的贮存,人工造林应多发展混交林。 相似文献
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[目的]研究杉木纯林转化为杉木阔叶树异龄复层混交林(简称杉阔复层林)对土壤团聚体稳定性和有机碳及养分储量的影响,为杉木人工林结构优化调控和可持续发展提供理论依据。[方法]以浙江开化不同树种构建的杉阔复层林和杉木纯林为研究对象,分析0～20 cm土层水稳性团聚体(WSA)稳定性以及全土和团聚体有机碳(SOC)、总氮(TN)、总磷(TP)和镁(Mg)储量的变化。[结果](1)杉阔复层林和杉木纯林0.25 mm水稳性团聚体(WSA_(0.25 mm))占比最高;与杉木纯林相比,复层林均显著增加5 mm水稳性团聚体(WSA_(5 mm))比例,同时也显著提高土壤平均质量直径(MWD)和几何平均直径(GMD),降低了团聚体分形维数(D)。(2)杉阔复层林和杉木纯林不同粒级团聚体中SOC和TN储量变化趋势一致,均为WSA_(5 mm)、2～5 mm粒径水稳性团聚体(WSA_(2～5 mm))0.25～2 mm粒径水稳性团聚体(WSA_(0.25～2 mm))WSA_(0.25 mm),而不同粒级团聚体中TP和Mg储量差异较小。(3)全土和团聚体有机碳及养分储量主要受5 mm粒径团聚体有机碳(SOC_(A5 mm))、2～5 mm粒径团聚体总氮(TN_(A2～5 mm))含量以及土壤pH的影响;团聚体稳定性主要受WSA_(5 mm)、土壤pH以及2～5 mm粒径团聚体有机碳(SOC_(A2～5 mm))含量的影响。(4)复层林不同伴生树种对团聚体组分、稳定性、土壤有机碳及养分储量有重要影响,主成分分析(PCA)发现,杉木纯林引入紫楠(杉木+紫楠)后显著影响全土和团聚体磷镁储量以及MWD和GMD;杉木纯林引入红茴香(杉木+红茴香)后显著影响全土和团聚体碳氮储量。[结论]杉阔异龄复层林的构建有利于改善杉木纯林土壤理化性质,尤以乔木阔叶树种紫楠和红茴香引入,对杉木纯林土壤团聚体稳定性和有机碳及养分储量的改善效果更佳。 相似文献
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亚热带地区杉木人工林和阔叶林土壤活性有机质研究(英文) 总被引：1，自引：2，他引：1
土壤活性有机质对土壤养分如氮、磷、硫的生物化学循环具有作用,其含量和质量影响土壤的初级生产力。本试验在中国科学院会同森林生态实验站通过对第一代、第二代杉木纯林和地带性阔叶林土壤活性有机质组分的对比研究,发现杉木纯林土壤活性有机质的含量低于地带性阔叶林。第一代杉木纯林易氧化有机碳、微生物生物量碳、水溶性有机碳和水溶性碳水化合物的含量分别比第二代杉木纯林高35.9%、13.7%、87.8%和50.9%,比地带性阔叶林的低15.8%、47.3%、38.1%和30.2%。在调查的三种林地内,土壤微生物生物量碳和水溶性有机碳含量下降幅度较大,其次为水溶性碳水化合物,而易氧化有机碳的变化最小。同时,杉木纯林土壤养分等理化性质也比地带性阔叶林低。这表明在杉木纯林取代地带性阔叶林以及杉木纯林连栽后林地的土壤肥力降低。图3 表2参26。 相似文献
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《四川林业科技》2021,(4)
为了探索不同林分类型对土壤化学性质的影响,以杉木纯林、柳杉纯林、鹅掌楸纯林、柳杉×楠木混交林等四个林分类型为研究对象,运用方差分析法分析不同林分类型的土壤化学性质及有机质含量差异。结果表明:不同林分类型土壤的pH值、速效钾、全磷、全钾、全氮存在显著性差异,有效磷、碱解氮、有机质无显著性差异;四种林分的土壤pH值在4.02～5.33之间,呈酸性,均随土壤深度的增加而增加;不同林分类型的土壤有机质、全氮、全磷、碱解氮和有效磷含量均随土层深度增加而减少;四种不同林分土壤全磷含量均表现为0～10 cm高于10～20 cm;杉木纯林、柳杉纯林、鹅掌楸纯林的土壤全钾含量随着土层的加深均存在上下波动,而柳杉×楠木混交林含量逐渐增加;四种林分土壤碱解氮、有效磷含量均随土层深度的增加而减少;杉木纯林和柳杉纯林土壤的速效钾含量随着土层的加深呈现先增加后减少的趋势,而鹅掌楸纯林和柳杉×楠木混交林则是逐渐增加;四种林分在0～10 cm、10～20 cm、20～40 cm、40～60 cm土层的平均供磷强度依次为2.64%、2.71%、2.57%和2.61%;鹅掌楸纯林和柳杉×楠木混交林土壤供钾强度均随着土层增加而增加,柳杉纯林则为先增加后减小。 相似文献
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Vegetation recovery is a key measure to improve ecosystems in the Loess Plateau in China. To understand the evolution of soil
microorganisms in forest plantations in the hilly areas of the Loess Plateau, the soil microbial biomass, microbial respiration
and physical and chemical properties of the soil of Robinia pseudoacacia plantations were studied. In this study, eight forest soils of different age classes were used to study the evolution of
soil microbial biomass, while a farmland and a native forest community of Platycladus orientalis L. were chosen as controls. By measuring soil microbial biomass, metabolic quotient, and physical and chemical properties,
it can be concluded that soil quality was improved steadily after planting. Soil microbial biomass of C, N and P (SMBC, SMBN
and SMBP) increased significantly after 10 to 15 years of afforestation and vegetation recovery. A relatively stable state
of soil microbial biomass was maintained in near-mature or mature plantations. There was an increase of soil microbial biomass
appearing at the end of the mature stage. After 50 years of afforestation and vegetation recovery, compared with those in
farmland, the soil microbial biomass of C, N and P increased by 213%, 201% and 83% respectively, but only accounting for 51%,
55% and 61% of the increase in P. orientalis forest. Microbial soil respiration was enhanced in the early stages, and then weakened in the later stage after restoration,
which was different from the change of soil organic carbon. The metabolic quotient (qCO2) was significantly higher in the soils of the P. orientalis forest than that in farmland at the early restoration stage and then decreased rapidly. After 25 years of afforestation and
vegetation recovery, qCO2 in soils of the R. pseudoacacia forest was lower than that in the farmland soil, and reached a minimum after 50 years, which was close to that of the P. orientalis forest. A significant relationship was found among soil microbial biomass, qCO2 and physical and chemical properties and restoration duration. Therefore, we conclude that it is possible to artificially
improve the ecological environment and soil quality in the hilly area of the Loess Plateau; a long time, even more than 100
years, is needed to reach the climax of the present natural forest.
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Translated from Acta Ecologica Sinica, 2007, 27(3): 909–917 [译自: 生态学报] 相似文献
12.
The soil microbial biomass and nutrient status under the native broadleaved forest and Cunninghamia lanceolata plantations at the Huitong National Research Station of Forest Ecosystem (in Hunan Province, midland of China) were examined
in this study. The results showed that after the native broadleaved forest was replaced by mono-cultured C. lanceolata or C. lanceolata, soil microbial biomass and nutrient pool decreased significantly. In the 0–10 cm soil layer, the concentrations of soil
microbial carbon and nitrogen in the broadleaved forest were 800.5 and 84.5 mg/kg, respectively. These were 1.90 and 1.03
times as much as those in the first rotation of the C. lanceolata plantation, and 2.16 and 1.27 times as much as those in the second rotation of the plantation, respectively. While in the
10–20 cm soil layer, the microbial carbon and nitrogen in the broadleaved forest were 475.4 and 63.3 mg/kg, respectively.
These were 1.86 and 1.60 times as much as those in the first rotation, and 2.11 and 1.76 times as much as those in the second
rotation, respectively. Soil nutrient pools, such as total nitrogen, total potassium, NH4
+-N, and available potassium, also declined after the C. lanceolata plantation replaced the native broadleaved forest, or Chinese fir was planted continuously. Less litter and slower decay
rate in pure Chinese fir plantation were the crucial factors leading to the decrease of soil microbial biomass and nutrient
pool in this area. Human disturbance, especially slash-burning and site preparation, was another factor leading to the decrease.
There were significant positive correlations between soil microbial carbon and nitrogen and soil nutrients. To improve soil
quality and maintain sustainable productivity, some measures, including planting mixed conifer with hardwood, preserving residues
after harvest, and adopting scientific site preparation, should be taken.
Translated from Chinese Journal of Applied Ecology, 2006, 17(12): 2,292–2,296 [译自: 应用生态学报] 相似文献
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WANG Qing-kui WANG Si-long 《林业研究》2006,17(3):197-200
Conversion of natural secondary broad-leaved forest to Cunninghamia lanceolata plantation is a common management practice in subtropical China. In this study, we compared soil physico-chemical properties, microbial biomass in one natural secondary broad-leaved forest and two C. lanceolata plantation sites to estimate the effects of forest conversion on soil microbial biomass at the Huitong Experimental Station of Forestry Ecology, Chinese Academy of Sciences. Concentrations of soil organic carbon, total nitrogen, NH4^＋-N and microbial biomass carbon and nitrogen were much lower under C. lanceolata plantations as compared to natural secondary broad-leaved forest. Soil microbial biomass C in the first and second rotation of C. lanceolata plantations was only 53%, 46% of that in natural secondary broad-leaved forest, and microbial biomass N was 97% and 79%, respectively. The contribution of microbial biomass C to soil organic C was also lower in the plantation sites. However, the contribution of microbial N to total nitrogen and NH4^＋-N was greater in the C. lanceolata plantation sites. Therefore, conversion of natural secondary broad-leaved forest to C. lanceolata plantation and continuous planting of C. lanceolata led to the decline in soil microbial biomass and the degradation of forest soil in subtropical China. 相似文献
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Effects of different vegetation restoration models on soil microbial biomass in eroded hilly Loess Plateau, China 总被引：2，自引：0，他引：2
Vegetation restoration is a key measure to improve the eco-environment in Loess Plateau, China. In order to find the effect
of soil microbial biomass under different vegetation restoration models in this region, six trial sites located in Zhifanggou
watershed were selected in this study. Results showed that soil microbial biomass, microbial respiration and physical and
chemical properties increased apparently. After 30 years of vegetation restoration, soil microbial biomass C, N, P (SMBC,
SMBN, SMBP) and microbial respiration, increased by 109.01%–144.22%, 34.17%–117.09%, 31.79%–79.94% and 26.78%–87.59% respectively,
as compared with the farmland. However, metabolic quotient declined dramatically by 57.45%–77.49%. Effects of different models
of vegetation restoration are different on improving the properties of soil. In general, mixed stands of Pinus tabulaeformis-Amorpha fruticosa and Robinia pseudoacacia-A. fruticosa had the most remarkable effect, followed by R. pseudoacacia and Caragana korshinkii, fallow land and P. tabulaeformis was the lowest. Restoration of mixed forest had greater effective than pure forest in eroded Hilly Loess Plateau. The significant
relationships were observed among SMBC, SMBP, microbial respiration, and physical and chemical properties of soil. It was
concluded that microbial biomass can be used as indicators of soil quality.
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Translated from Journal of Natural Resources, 2007, 22(1): 20–27 [译自: 自然资源学报] 相似文献
15.
We studied the distribution of soil nutrients, the number of soil microorganisms, soil enzyme activities, and their relationships
in pure and mixed plantations. Soil enzyme activities, the number of soil microorganisms, and soil nutrients were measured
in plantations of Chinese pine (Pinustabulaeformis), larch (Larix kaempferi), sharp tooth oak (Quercus aliena var. acuteserrata), Manchurian catalpa (Catalpa fargesii), and mixed plantations in the Qinling Mountains, China. Compared with pure plantations, the conifer-broad-leaved broadleaf
mixed plantations increased total N, available N, total P, available K, and organic matter in the forest soil; promoted the
activities of invertase and urease by 16.7% and 53.8%; and increased the total amount of soil microorganisms by 95.9% and
the number of bacteria by 104.5% (p<0.05). The correlations between soil enzymes, number of microorganisms, and soil nutrients were significant (p<0.05), and the correlations between the number of soil bacteria and basic nutrient prosperities (total N, available N, available
K, and organic matter (OM)) were significant or highly significant. The correlations between the number of soil actinomycetes,
and soil total N, available N, OM, and pH were also significant or highly significant. A suitable mixture of planted conifers
and broad-leaved species improves the quality and amount of soil nutrients, increases the number of soil microorganisms and
changes their redistribution. The change of soil enzymes and the number of soil microorganisms are indications of the change
tendency of soil nutrients.
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Translated from Journal of Northwest A&F University (Nat. Sci. Ed.), 2008, 36(10): 88–94 [译自: 西北农林科技大学学报] 相似文献
16.
为评价我国北方大规模人工造林对土壤磷素转化及磷素有效性的影响,对半干旱沙地樟子松人工林和天然植被(疏林草地)不同层次(0～5 cm, 5～20 cm)土壤中不同形态磷组分和磷酸单酯酶活性进行了比较.结果表明:除人工林土壤中活性有机磷不受土壤深度影响外,各样地表层土壤中各种磷素含量和酶活性均显著高于低层土壤,但分层效应在人工林中低于疏林草地;与疏林草地土壤相比,除Al-P外,人工林土壤中各种磷素绝对含量和酶活性均显著降低,总有机磷和Ca-P在全磷中的比例显著下降,而活性磷,Al-P和Fe-P占全磷的比例增加.可见表层土壤是磷素转化最活跃的区域,凋落物分解是土壤磷的主要来源;用樟子松进行人工造林促进了有机磷的矿化和Ca-P的溶解,提高了土壤磷素的有效性,同时导致土壤总磷库逐渐耗竭.要维持该人工防护林功能和稳定性,必须对地被物予以保护,并进行适当施肥.表3参38. 相似文献
17.
Jonathan C. Onyekwelu 《林业研究》2012,23(2):253-260
We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15 and 15-30 cm from plantations of six different ages during the rainy season, dry seasons, and their transitions. We used plate count and fumigation-extraction methods to determine microbe population and microbial biomass carbon (MB-C) and nitrogen (MB-N), respectively. Plantation age did not affect microbial indices, implying a non-significant effect of plantation development on microbial communities. It could also imply that soil microbial indices had already stabilized in the sampled plantations. Seasonal variation and soil depth had significant effects on microbial indices. At 0-15 cm soil depth, mean MB-C increased from 50.74 μg g-1 during the peak of the dry season (i.e. March) to 99.58 μg g-1 during the peak of the rainy season (i.e. September), while it increased from 36.22 μg g-1 to 75.31 μg g-1 at 15-30 cm soil depth between the same seasonal periods. Bacteria populations and MB-N showed similar increasing trends. Correlations between MB-C, MB-N, microbe populations, and rainfall were positive and linear. Significantly higher microbial activities took place in the plantations during the rainy season, increased with soil wetness, and decreased at greater soil depth. 相似文献
18.
Soil properties under an exotic plantation (Pinus caribaea) and an indigenous plantation (Podocarpus imbricatus) were compared with adjacent secondary forests and abandoned land in the tropical forest areas of Jianfengling National Nature
Reserve in Hainan province, southern China. The surface soil (0–0.2 m) under Pi. caribaea has higher bulk density, lower soil organic carbon, total N, total K, available N, microbial biomass carbon, and smaller
soil microbial communities (as indicated by soil Biolog profiles) than under Po. imbricatus. Both land use types showed negative cumulative soil deterioration index (DI) compared to secondary forests. However, compared
to abandoned land (DI = –262), the soil quality of Po. imbricatus showed improvement (DI = –194) while that of Pi. caribaea showed deterioration (DI = –358). These results demonstrated that these exotic pine plantations can significantly and negatively
influence soil properties. By contrast, our results showed that adoption of indigenous species in plantations, or natural
regeneration, can improve soil quality. 相似文献
19.
Assessing the effects of vegetation types on carbon storage fifteen years after reforestation on a Chinese fir site 总被引：2，自引：0，他引：2
Forest ecosystems play a significant role in sequestering carbon (C) in biomass and soils. Plantations established in subtropical China since the 1980s, mainly of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) in monocultures, have proved to be major C sinks. However, information is lacking about whether mixing Chinese fir with broadleaved tree species will increase stand growth and C sequestration. We address this question by comparing a pure Chinese fir plantation and two mixed plantations established in 1990 at Huitong Experimental Station of Forest Ecology, Hunan Province, China. The mixed plantations include Chinese fir and either Kalopanax septemlobus (Thunb.) Koidz or Alnus cremastogyne Burk., planted at 4:1 ratios. We found that total C storage was 123, 131 and 142 Mg ha−1 in the pure plantation, mixed plantation with K. septemlobus, and mixed plantation with A. cremastogyne, respectively. The mixed plantation with A. cremastogyne increased C storage in biomass relative to the pure Chinese fir plantation (P < 0.05). No significant difference was detected between mixed plantations. Soil C storage did not differ among these plantations, ranging from 67.9 ± 7.1 to 73.3 ± 9.1 Mg ha−1, which accounted for about 55% of the total C pools. Our results indicated that as the mixture of Chinese fir and broadleaved species will increase both biomass C and soil C storage over pure Chinese fir, and will do it, within 15 years of planting. 相似文献