共查询到20条相似文献，搜索用时 187 毫秒
1.
《森林与环境学报》2010,(2)
通过对福建省平和天马国有林场3种相思人工林凋落物的数量及其组成进行为期1a的定位监测,同时分析凋落物不同组分含碳率,估算出凋落物碳的年归还量及其季节动态。结果表明,黑木相思林的年凋落物量最大,约为7338.28kg·hm-2,其次为卷荚相思林和马占相思林;凋落叶在凋落物中占绝对优势,分别占总凋落物的65.32%、83.71%和68.10%。3种相思人工林凋落物的月变化均呈双峰型季节变化。卷荚相思林、黑木相思林和马占相思林凋落物碳年归还量分别为2875.79、3641.37和2964.91kg·hm-2,卷荚相思林凋落物碳归还季节变化表现为秋季夏季冬季春季;黑木相思林表现为春、夏和秋3个季节较大,冬季较小;马占相思林表现为秋季夏季春季冬季。 相似文献
2.
根据定位观测的数据,探讨了杉木人工林凋落物量及其分解过程中碳素释放率.结果表明,14～16年生杉木人工林平均每年约有1 201.24 kg*hm-2凋落物,其中以针叶为最多,占凋落物总量的69.8%,其次是小枝,占24.54%,落果和其它碎屑物质仅占5.63%.不同组分的碳素含量高低顺序排列为:针叶＞落果＞碎屑＞枯枝,变异系数在3.36%～8.24%之间.针叶、枯枝的碳素含量均随时间的推移而下降,而其释放率均随时间的推移而增大,针叶中碳素的释放速率明显高于枯枝中碳素的释放速率.凋落物中碳素的释放规律与总干物质的分解速度并不完全一致.杉木人工林年凋落物碳素释放量约为149.25 kg·hm-2a-1,占凋落时碳素量(548.24 kg·hm-2a-1)的27.22%.经一年的分解后,针叶释放碳素量为120.12 kg·hm-2a-1,占总释放量的81.03%,枯枝、落果及其它碎屑释放碳素量为29.13 kg·hm-2a-1,占总释放量的18.97%. 相似文献
3.
[目的]研究外源性氮和磷对马占相思凋落叶的分解速率、分解过程中N、P、K含量和土壤生化特性的影响,以便为森林土壤养分管理提供参考。[方法]以广东省云勇林场马占相思林下凋落叶为试验材料,采用尼龙网袋分解法,设置对照(CK)、施N(10 g·m~(-2))、施P(5 g·m~(-2))、施N+P(N 10 g·m~(-2)+P 5 g·m~(-2))4种处理,每隔3个月取样1次,并测定凋落叶残留量和N、P、K含量。[结果]表明:施N、P和N+P处理对马占相思凋落叶的分解均为促进作用。各处理马占相思凋落叶的N含量在分解过程中大致保持稳定,施P和N+P处理的凋落叶P含量在分解过程中总体呈波动性上升,而各处理的凋落叶K含量变化规律不明显。施N、P和N+P处理提高了马占相思林土壤的有机质和全N含量,促进脲酶、磷酸酶及过氧化氢酶的活性。[结论]施N、P和N+P处理促进了马占相思凋落叶的分解,有利于马占相思林的养分循环。 相似文献
4.
四川省茂县四种人工林凋落物研究 总被引：3，自引：0，他引：3
对四川省茂县四种人工林的年凋落量、凋落物组成、凋落动态及分解率进行了观测.结果表明:云南松、日本落叶松、连香树、油松这四种人工林的年凋落量依次为6.42、4.87、3.79、3.45 t·hm-2a-1;四种人工林其叶的年凋落量占年总凋落量的比例明显大于其它组分的;四种人工林其叶的凋落集中在10、11月,呈现出明显的温带森林凋落的特征;连香树、日本落叶松、油松、云南松其花的凋落高峰期分别出现在4月、4月、6月和6～7月;日本落叶松和油松、云南松其果的凋落高峰期分别出现在9月和4月;叶鞘和芽鳞分别在8月和7月时出现最大凋落量;其它组分凋落的动态规律不明显;各人工林凋落物的分解率随其阔叶所占总凋落量比例的增加而增加. 相似文献
5.
木荷凋落物分解及对土壤作用规律的研究 总被引：18，自引：0，他引：18
在福建省永春碧卿林场开展的木荷凋落物分解及土壤淋溶试验表明 :木荷人工林凋落物量和养分积累量下坡 >中坡 >上坡 ,养分积累量Ca >N >K >Mg >Fe >P >Zn >Cu ;凋落物分解的失重率Ws与时间t之间存在Ws =34 45 2Lnt -3 0 741(R =0 98)的对数关系 ;木荷凋落物可通过增加土壤有机质 ,提高土壤和下渗液的盐基量 ,提高土壤pH值 ,降低土壤水解性总酸度等途径来缓解土壤的酸化作用 相似文献
6.
研究广西南宁市马占相思人工林5种微量元素(Fe,Mn,Zn,Cu和B)的分布和生物循环特征以及随林龄的变化趋势.结果表明:1)林木各组分微量元素含量表现为树叶＞枯枝＞干皮＞活枝＞树根＞干材,各组分中微量元素Mn含量最高,其次是Fe,zn和B,以Cu最低;2)林地土壤微量元素Fe含量最高,其次是Mn,Zn和B,以Cu最低;3)4,7和11年生马占相思人工林林分微量元素的总贮存量依次为13.953,22.357和28.835 kg·hm-2,其中乔木层微量元素贮存量占47.37%～58.68%,林下植被和凋落物微量元素贮存量分别占14.76%～23.54%和26.63%～29.10%;4)4年生马占相思人工林微量元素贮存量主要集中在树叶和树枝,7和11年生则主要集中在树干和树根;5)3个林龄林分微量元素年净积累量依次为1.536,1.750和1.652 kg·hm-2a-1,林木各组分微量元素年净积累量总的变化趋势为树干＞树枝或树根＞树叶＞树皮,同一组分各微量元素年净积累量变化顺序一致,即Mn＞Fe＞Zn(B)＞Cu;6)3个林龄林分微量元素年吸收量分别为5.423,5.862和5.273 kg·hm-2a-1,年归还量分别为3.771,4.112和3.737 kg-hm-2a-1,利用系数分别为0.821,0.479和0.312,循环系数分别为0.695,0.701和0.709,周转期分别为1.753,2.979和4.522年. 相似文献
7.
湖南会同毛竹林土壤碳循环特征 总被引：6，自引：1，他引：5
测定和分析湖南会同毛竹林土壤的碳贮量和各组分呼吸量.结果表明:毛竹林土壤有机碳贮量为115.558 t·hm-2,矿质土壤层、凋落物层和根系分别占96.01%,0.64%和3.34%;毛竹林地土壤年呼吸排放碳总量为9.257 t·hm-2a-1,异养呼吸、自养呼吸和凋落物年呼吸最分别占59.49%,28.27%和12.24%;毛竹林细根年生长量为6.895 t·hm-2a-1,年分解量为0.312 t·hm-2a-1,细根年周转率为0.93次·a-1;毛竹林年凋落物进入土壤的碳总量为2.245 t·hm-2a-1,地上和地下凋落物分别占78.5%和21.5%. 相似文献
8.
9.
南宁马占相思人工林生态系统碳素密度与贮量 总被引：7，自引：0，他引：7
对南宁市马占相思人工林3个不同年龄阶段(4,7和11年生)生态系统的碳素密度、贮量及其空间分布特征进行研究.结果表明:马占相思不同器官中碳素密度为455.4～494.5 g·kg-1,各器官碳素密度表现为:皮＞干或叶＞枝＞根;同一林分中各层次碳素密度表现为乔木层＞灌木层＞草本层;0～80 cm土层中碳素密度随林龄增加而增大,且随土层深度增加而下降;3个年龄阶段马占相思人工林生态系统总碳贮量分别为117.63,176.70和202.08 t·hm-2,其中乔木层分别占25.67%,46,10%和50.91%,灌木和草本层分别占1.82%,1.65%和1.62%,土壤层分别占69.84%,49.62%和44.59%,凋落物层分别占2.68%,2.34%和2.88%;3个年龄阶段林分碳素年净固定量分别为10.66,15.70和12.55 t·hm-2a-1,其中乔木层碳素年净固定量分别为7.54,12.14和9.36 t·hm-2a-1,占林分总量的70.17%,74.14%和74.58%;凋落物层碳素年固定量分别为312,3.56和3.191 t·hm-2a-1,占林分总量的70.17%.74.14%和74.58%. 相似文献
10.
毛竹、杉木人工林生态系统碳平衡估算 总被引：4，自引：0，他引：4
采用CID-301PS光合测定仪,对湖南会同林区毛竹和杉木人工林土壤CO2排放动态进行观测,并结合现存生物量调查,对其生态系统碳平衡特征进行估算.结果表明:毛竹和杉木林生态系统碳贮量分别为144.3和152.52 t·hm-2,并且其碳贮量空间分布格局基本一致,土壤层是主要部分,其次为乔木层,凋落物层和林下植被层所占比例最小.毛竹林土壤层有机碳贮量占76.89%,乔木层占22.16%,凋落物和林下植被层分别占0.51%和0.41%;杉木林土壤层碳贮量占62.03%,乔木层占34.99%,凋落物和林下植被层分别占2.28%和0.70%.毛竹林和杉木林生态系统年固定CO2总量分别为38.87和26.95 t·hm-2a-1,但其每年以土壤异养呼吸和凋落物呼吸的形式排放CO2的量分别为24.35和15.75 t·hm-2a-1,毛竹林和杉木林生态系统年净固定CO2的量分别为14.52和11.21 t·hm-2a-1,折合成净碳量分别为3.96和3.07 t·hm-2a-1. 相似文献
11.
From 2002 to 2003, based on the investigation of sample plots and stem analysis of remained plantation communities in the areas of returning farmland to forest in the 1980s in Datong County, Qinghai Province, this paper studies tree productivity and moisture potential productivity of six types of plantations on the land of returning farmland to forest, such as green poplar (Populus cathayana Rehd.) and shrub mixed forest, Asia white birch (Betula platyphylla) and China spruce (Picea asperata) mixed forest, Dahurian larch (Larix gmelinii) pure forest, China spruce pure forest and Asia white birch pure forest and so on. The results show that: in sub-humid region of Loess Plateau, 3 000 trees per hm2 is a proper standard of planting density. Under current condition, the productivity index of green poplar and shrub mixed forest, Asia white birch pure forest, China spruce pure forest, and Asia white birch and China spruce mixed forest with the density of 2 100–3 333 trees per hm2 can serve as potential productivity standard of actual biomass of arbor established forest. In sub-humid area, Thornthwaite Model is adopted to estimate plant climate potential productivity, which is about 8 462 kg•hm–2•a–1. The actual potential water productive efficiency of Purplecone spruce (Picea purpurea) and Asia white birch pure established forest are 17.22 and 22.14 kg•mm–1•hm–2•a–1 respectively, and that of green poplar and shrub mixed established forest, and Asia white birch and China spruce mixed established forest are 21.14 and 19.09 kg•mm–1•hm–2•a–1 respectively. The potential productivity of green poplar and shrub mixed forest, Asia white birch and China spruce mixed forest, China spruce pure forest and Asia white birch pure forest which have grown into forest with the density of 3 000 trees per hm2 have attained or been close to that of local climax community, which is local maximum tree productivity at present. These types of forestation models are the developing direction of the returning farmland to forest project. 相似文献
12.
在孟加拉诺阿卡利地区及相临裸地,对海岸植被(12年和17年生无瓣海桑Sonneratia apetala)进行探索性研究,以便了解海岸造林对土壤特性的影响.在三种不同地带(内陆、中部、海边),在12年生和17年生无瓣海桑林下,土壤深度分别为0-10,10-30和30-40cm,土壤湿度、土壤粒度、有机质、C含量、总N、pH、有效P、K、Na、Ca和Mg含量明显高(p≤0.05,p≤0.01,p≤0.001)于其相临裸地的数据,土壤含盐量明显(p≤0.01)低于其相临裸地的数据.在内陆CharAlim植被,土壤表面的土壤湿度,土壤粒度,有机质,C含量、总N、pH、土壤含盐量、有效P、K、Na、Ca和Mg含量分别为:31.09%、2.24 g·cm-3、2.41%、4.14%、0.58%、7.07、O.09 dS·cm-1、28.06 mg·L-1、O.50 mg·L-1、11.5 mg·L-1、3.30 mg·L-1和2.7 mmol·kg-1;而在相邻的Char Rehania贫瘠地区的相同土壤深度,其相关值分别为:16.69%、1.25g·cm-3、O.43%、0.74%、O.25%、6.57、0.13 dS·cm-1、13.07mg·L-1、O.30mg·L-1、1.4 mg·L-1、O.30 mmol·kG-1和0.50 nag·L-1.然而,在小内陆到海边的植被中,土壤湿度、土壤密度、有机质、C含量、总N、pH、有效P、K、Na和Ca含量逐渐降低,而土壤含盐量、Na和Mg含量却逐渐增加.虽然,在植被与相临裸地的不同土壤深度中土壤质地不同,植被地中砂土份额明显(p≤0.01)低于相临裸地,而粉砂土份额则明显(p≤0.001)高于裸地.在本研究中,所有参数的评价也在为其他地区相关研究得到应用. 相似文献
13.
Guo Jianfen Xie Jinsheng Lu Haoliang Liu Dongxia Yang Yusheng Chen Guangshui 《中国林学(英文版)》2004,6(1):33-36
The amount of carbon returned through litterfall and its seasonal pattern were studied in a natural forest of Castanopsis kawakamii (NF) and adjacent monoculture plantations of C. kawakamii (CK) and Chinese fir (Cunninghamia lanceolata) (CF) in Sanming, Fujian Province, China. Mean annual carbon return through total litterfall over 3 years (from 1999 to 2001)
was 5.097 t·hm−2 in the NF, 4.337 t·hm−2 in the CK and 2.502 t·hm−2 in the CF respectively. Of the total carbon return in the three forests, leaf contribution accounted for 58.96%, 68.53% and
56.12% and twig 24.41%, 22.34% and 26.18%, respectively. The seasonal patterns of carbon return from total litterfall and
leaf-litter were quite similar among the three forests. A peak of carbon input from litterfall in the NF and the CK occurred
in spring except for the highest annual C return through branch litter of the NF in summer, while the CF showed the maximum
C return in summer. The results of this study demonstrate that the natural forest has a greater C return through litterfall
than monoculture plantations, which is beneficial to the increase of soil organic matter storage and the maintenance of soil
fertility.
[Supported by the Teaching and Research Award Program of MOE P.R.C. (TRAPOYT) and the Key Basic Research Project of Fujian
Province (2000F004)] 相似文献
14.
Chen Hongji 《林业研究》1999,10(3):181-182
Different types of plantations were observed in Baishilazi National Nature Reserve, Liaoning Province, for 34 a. The environmental
quality ofAbies holophylla plantations was analyzed under different cutting systems. Analysis factors included soil erosion rate, humification degree
of litters, and water hold capacity. The surface soil loss of clear cutting area was 19000t·km−2·a−1 more than that of selective cutting area. The content of soil organic matter in board-leaved—Abies holophylla forest was 4.62% more than that in pure stand, and the water hold capacity of the mixed forest was 1.43 time of that of pure
stand. The mixed forest of board-leaved—Abies holophylla by selective cutting can upgrade the ecological environment quality.
This paper is a part of a key project from Liaoning Science Committee.
Responsible editor: Zhu Hong 相似文献
15.
The concentrations and seasonal dynamics of DOC in forest floors of monoculture plantations ofCastanopsis kawakamii and Chinese fir (Cunninghamia lanceolata) were assessed in Sanming, Fujian, China (26°11′30″N, 117°26′00″E). Forest floor samples were taken in January, April, July
and October in 2002 and divided into undecomposed material (horizon Oi), partially decomposed organic material (horizon Oe),
and fully decomposed organic material (horizon Oa). Upon collection, DOC concentrations of samples were analyzed by a High
Temperature TOC. The results showed that the annual average DOC concentration of Chinese fir (1341.7 mg·kg−1) in the forest floor was higher than that ofCastanopsis kawakamii (1178.9 mg·kg−1). Difference in DOC concentrations was observed among three horizons of the forest floor. DOC concentration of forest floor
in the two forests was the highest in horizon Oe. Seasonal trends of DOC concentrations in different horizons of forest floors
were similar and the maximal value occurred in autumn (or winter). The concentration and temporal change of DOC in studied
forests were probably related to the variation in moisture, temperature, biological activity and quantity of organic matter
in the forest floor.
Foundation item: This study was supported by the Teaching and Research Award program for MOE P.R.C. (TRAPOYT)
Biography: ZHANG Jiang-shan (1946-), male, Researcher in Fujian Normal University, Fuzhou 350007, P.R. China.
Responsible editor: Zhu Hong 相似文献
16.
Microclimate in agroforestry systems in central Amazonia: does canopy closure matter to soil organisms? 总被引：7，自引：0，他引：7
Christopher Martius Hubert Höfer Marcos V.B. Garcia Jörg Römbke Bernhard Förster Werner Hanagarth 《Agroforestry Systems》2004,60(3):291-304
Microclimate was recorded and soil organisms were collected 1997-1999 in ecosystem stands of contrasting structure in central
Amazonia (a primary forest, a 12-year secondary forest, two different agroforestry systems, a rubber tree (Hevea brasiliensis) plantation, and a peach palm (Bactris gasipaes) monoculture with a densely closed canopy). The aim was to look at the effects of canopy closure on microclimate and soil
organisms. Monthly maxima temperature, average air and soil temperatures, and saturation deficit were highest in September
1997, and total annual rainfall in 1997 was 12-28% lower than in the other study years. The monthly average litter temperatures
were consistently 2-4 °C higher in the plantation sites than in the rainforest and the secondary forest, and temperatures
on single days (not the monthly averages) in the plantations were up to 10 °C higher than in the primary forest. The highest
average litter and soil temperatures and the highest temperature maxima were recorded in the agroforestry plantations. Canopy
closure strongly determined the litter temperatures in the sites. Soil macrofauna biomass was also strongly correlated to
canopy closure (linear regression, P = 0.05). We conclude that a well developed canopy effectively protects the soil macrofauna
from high temperature variation and drought stress. Therefore, optimizing these agroforestry systems for canopy closure may
contribute to a better management of the beneficial soil decomposer community.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
17.
The effects of soil animals on soil nitrogen （N） mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distinguished with Tullgren and Baermann methods under three Pinus sylvestris var. mongolica Litv. plantations in Zhanggutai sandy land, China. In addition, soil N mineralization rate was also measured with PVC closed-top tube in situ incubation method. The soil animals collected during growing season belonged to 13 orders, 5 groups, 4 phyla, whose average density was 86 249.17 individuals-m^-2. There were significant differences in soil animal species, densities, diversities and evenness among three plantations. Permanent grazing resulted in decrease of soil animal species and diversity. The average ammonification, nitrification and mineralization rates were 0.48 g：m^-2·a^-1, 3.68 g·m^-2·a^-1 and 4.16 g·m^-2·a^-1, respectively. The ammonification rate in near-mature forest was higher than that in middle-age forests, while the order of nitrification and net mineralization rates was： middle-age forest without grazing 〈 middle-age forest with grazing 〈 near-mature forest with grazing （P〈0.05）. Soil N mineralization rate increased with soil animal amounts, but no significant relationship with diversity. The contribution of soil animals to N mineralization was different for different ecosystems due to influences of complex factors including grazing, soil characteristics, the quality and amount of litter on N mineralization. 相似文献
18.
M. K. da Silva Moço E. F. da Gama-Rodrigues A. C. da Gama-Rodrigues R. C. R. Machado V. C. Baligar 《Agroforestry Systems》2009,76(1):127-138
Agroforestry systems deposit great amounts of plant residues on soil and this leads to high levels of soil organic matter
content and has increased soil biodiversity and improved its conservation. This study compares the distribution of meso and
macrofaunal communities in soil and litter under cacao agroforestry systems and in a natural forest in the southern Bahia
state of Brazil. Soil and litter samples were obtained in September 2003, February 2004, and August 2004 in five cacao agroforestry
systems. The systems evaluated included: cacao renewed under Erythrina sp. (Erythrina poeppigiana) (CRE); cacao renewed under natural forest (Cabruca, CRF); an old cacao system under Erythrina sp. (OCE); an old cacao system under a natural forest system (Cabruca, OCF) and a cacao germplasm collection area (CGC).
As a reference soil and litter under a natural forest (NF) was included. Organisms were collected over a 15-day period with
a Berlese–Tullgren apparatus. The density and richness of total fauna varied distinctly according to sites, sampling time
and material sampled (soil and litter). 16,409 of fauna were recovered from soil and litter samples and the density of total
fauna was 2,094 individuals m−2 in the litter and 641 individuals m−2 in the soil. The richness was 11.8 in the litter and 7.5 in the soil. The cacao agroforestry systems adopted for growing
cacao in the southern Bahia region of Brazil have beneficial effects on the soil and litter faunal communities, and such systems
of cacao cultivation could be considered as a conservation system for soil fauna. The development of a litter layer resulted
in higher abundance and diversity of soil fauna. 相似文献
19.
Agroforestry systems based on poplar (Populus deltoides) are becoming popular in eastern and northern parts of India. Therefore studies on the structure and function of the systems
are important. The investigations included allometric equations for above- and belowground tree components, crop and plantation
floor biomass and litter fall estimation at Pusa, Bihar, India. Biomass, floor litter mass, litter fall and net primary productivity
(NPP) of plantations increased with an increase in age of trees whereas, crop biomass for any specific crop interplanted with
poplar decreased with the age of the plantation. The total plantation biomass increased from 12.08 to 90.59 Mg ha−1 and NPP varied from 5.69 to 27.9 Mg ha−1 year−1. The biomass accumulation ratio ranged from 2.1 to 3.2. Total annual litter fall was in between 1.95 and 10.00 Mg ha−1 year−1, of which 92–94% was contributed by leaf litter. Compartmental models were developed for dry matter distribution in agroforestry
systems involving young (3-year-old) and mature (9-year-old) poplar trees interplanted with various crops, the crops being
grown in two rotations maize (Zea mays) – wheat (Triticum aestivum) – turmeric (Curcuma domestica) and pigeonpea (Cajanus cajan) – turmeric. This study substantiates the potential of Populus deltoides G3 under agroforestry combinations. 相似文献
20.
The present study was an effort to understand the amount of litter fall and its subsequent decomposition and quantify the release of available nutrients and soil physicochemical characteristics in plantations of four forest tree species(Lagerstroemia parviflora, Tectona grandis, Shorea robusta and Michelia champaca) in the Chilapatta Reserve Forest of the Cooch Behar Wildlife Division in the Terai zone of West Bengal, India. The most litter(5.61 Mg ha~(-1))was produced by T. grandis plantation and the least(4.72 Mg ha~(-1)) by L. parviflora. The material turnover rate to the soil through decomposition from total litter was fastest during the first quarter of the year and subsequently decreased during the next two quarters. The material turnover rate was only 1 year, which indicates that more than90% of the total litter produced decomposed within a year.The available primary nutrient content in litter varied across the four plantations over the year. The plantations generally did not significantly influence the soil physical characteristics but did significantly influence the availability of primary nutrients and organic carbon at two depths(1–15 and16–30 cm) over the year. The availability of soil primary nutrients in the four plantations also increased gradually from the first quarter of the year to the third quarter and then decreased during the last quarter to the same level as in the first quarter of the year at both depths. The availability for soil organic carbon in the plantations followed a similar trend. The amount of litter produced and the material turnover in the soil in the different plantations differed, influencing the nutrient availability and organic carbon at the plantations. The amount of soil organic carbon was highest for T. grandis(2.52 Mg ha~(-1)) and lowest for L. parviflora(2.12 Mg ha~(-1)). Litter is the source of soil organic matter,and more the litter that is produced by the plantations, the higher will be the content and amount of soil organic carbon in the plantation. 相似文献