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1.
田林老山中山杉木人工林生产力及营养元素循环的研究 总被引：3，自引：0，他引：3
林卫江 《广西农业生物科学》1991,(4)
广西田林县老山林场中山区气候冷凉潮湿,土壤肥力较高,能满足杉木速生要求。17年生杉木人工林乔木层的生物量达138.46t/ha,平均净生产量为8.15t/ha·a,与杉木中心产区相当。乔木层对N,P,K,Ca,Mg5种营养元素的吸收量为224.04kg/ha·a,其中42.3％存留在林木层,42.5％通过凋落物,15.2％通过降雨淋洗归还土壤。通过凋落物归还是N,P,Ca,Mg归还的主要途径,K的归还主要通过降雨淋洗;K,Ca,Mg的循环系数较大,分别达到0.58,0.68和0.60;N,P相对较小,分别为0.48和0.33。林木正处于生长旺盛阶段,杉木对5种营养元素的吸收量、存留量和归还量以及循环系数都有较高水平,生物量积累也较大。 相似文献
2.
厚荚相思人工林营养元素生物循环的研究 总被引：14，自引：0，他引：14
对1.5～4.5年生厚荚相思人工林5种营养元素(N、P、K、Ca和Mg)的含量、积累、分配和生物循环以及它们随林分年龄的变化趋势进行了研究.结果表明,厚荚相思人工林不同器官中营养元素含量排序大致为树叶＞于皮＞树枝＞树根＞干材,林木各器官中营养元素含量均以N最高,其次是Ca,然后是K和Mg,P最低;厚莫相思人工林营养元素贮存量依次为145.00～611.70 kg/hm2,随生长过程中生物量的增加而增大;不同器官微量元素贮存量的分配随林分年龄的增长发生变化,1.5年生时营养元素贮量主要集中在树叶和树枝,2.5～4.5年生时营养元素贮量则主要集中在树干和树根;林分营养元素年净积累量为96.66～135.93 kg/(hm2·a),林木各组分营养元素年净积累量总的变化趋势以树干最高,树皮最低,年吸收量为116.50～258.10 kg/(hm2·a),年归还量分剐为19.83,117.21,114.83,122.17 kg/(hm2·a),利用系数分别为0.80,0.78,0.55和0.42,循环系数分别为0.17,0.49,0.48和0.47,周转期分别为7.34,2.64,3.73,5.01年. 相似文献
3.
对湖南汨罗桤木人工林5种营养元素(N、P、K、Ca、Mg)的季节动态、空间分布及生物循环进行研究。结果表明:桤木叶片营养元素含量均为春季最高,干材养分含量偏低,且大部分元素在春季达最低点,所以建议桤木干材在春季采伐;树皮有大量Ca富集,根系中营养元素季节变化不明显。林下植被元素含量从春季到冬季有下降的趋势,枯落物、土壤层中元素含量季节变化趋势不明显,K元素各个土层各个季节含量变化都不是很大。桤木人工林生态系统各组分养分含量变化差异较大,以树叶中养分含量最高,30-60cm土壤层中含量最低;乔木层各器官排序为树叶>树皮>树枝>树根>树干,各器官中养分元素含量以N最高,P最低。桤木人工林生态系统养分总贮量为167 809.80kg/hm2,其中乔木层5种元素总量为754.77kg/hm2,占生态系统养分总贮量的0.45%,林下植被与枯落物层二者的养分积累量为254.04kg/hm2,占生态系统养分总贮量的0.15%。营养元素的年积累量为350.18kg/hm2,以N的积累量最大。桤木年吸收量、归还量、存留量分别为449.38,348.23,101.15kg/hm2。营养元素的循环系数为0.77,利用系数为0.60,周转期为2.17年,循环速率依次为N>Ca>Mg>K>P。 相似文献
4.
《农业研究与应用》2017,(4)
采用标准样地法对广西天峨县12年生光皮桦人工林5种养分元素(N、P、K、Ca、Mg)的含量、积累量及其分配特征进行了研究。结果表明,光皮桦各组分养分含量由大到小依次为树叶、树枝、干皮、树根、干材;不同器官养分元素含量以N、K或Ca最高,其次是P,Mg最低。12年生光皮桦人工林养分积累量为1118.37 kg/hm2,其中乔木层、灌木层、草本层和凋落物层养分积累量分别为930.18、64.88、35.34和87.97 kg/hm2,分别占养分总积累量的83.17%、5.80%、3.16%和7.87%。光皮桦人工林5种养分元素年净积累量为77.53 kg/hm2,不同器官年净积累量排序为干材树枝干皮树叶树根。 相似文献
5.
太行山地区侧柏人工林主要养分元素分配及循环特征 总被引：2，自引：0，他引：2
为了解侧柏(Platycladus orientalis)人工林养分循环特征,以太行山丘陵区侧柏人工林为研究对象,采用样地标准木收获法,对其生物量和养分循环进行了研究.结果表明:(1)侧柏人工林(26 a)生物量约45.55t/hm2,林分净生产力为2.07 t/hm2;生物量分配排序为;树干树根树皮树枝树叶.(2)林分营养元素积累量为455.23 kg/hm2,积累量的排序为:CaNP.(3)灌草植被层营养元素积累量顺序为:CaNP,灌草层3种元素总贮量仅占乔木层的5.5%.(4)凋落物营养元素年归还量为337.12 kg/hm2,3种营养元素归还量排序为:CaNP,Ca的年归还量最高,为271.66 kg/hm2,分别是N和P的4.42倍和69.12倍.(5)年吸收量、年存留量、养分年归还量和富集系数排序均为CaNP;吸收系数排序为CaNP;利用系数、循环系数排序是NCaP,侧柏对N的利用系数最大;Ca的富集能力最强.分别是N,P的1.9和2.8倍.侧柏的N周转时间最短(1.22 a),P周转时间最长(3.63 a),Ca周转时间居中(1.43 a). 相似文献
6.
《农业研究与应用》2017,(4)
采用标准样地法对广西天峨县12年生光皮桦人工林5种养分元素(N、P、K、Ca、Mg)的含量、积累量及其分配特征进行了研究。结果表明,光皮桦各组分养分含量由大到小依次为树叶、树枝、干皮、树根、干材;不同器官养分元素含量以N、K或Ca最高,其次是P,Mg最低。12年生光皮桦人工林养分积累量为1118.37 kg/hm2,其中乔木层、灌木层、草本层和凋落物层养分积累量分别为930.18、64.88、35.34和87.97 kg/hm2,分别占养分总积累量的83.17%、5.80%、3.16%和7.87%。光皮桦人工林5种养分元素年净积累量为77.53 kg/hm2,不同器官年净积累量排序为干材>树枝>干皮>树叶>树根。 相似文献
7.
为定量分析植被恢复进程的变化特征,以太行山丘陵区的栓皮栎人工林为研究对象,在样方调查的基础上,对其各器官N、P、Ca 3种营养元素的含量、积累、分配和养分循环变化情况进行研究。结果表明：1）不同植物器官中,营养元素含量差异明显;各龄级中,营养元素含量最多的器官是树叶,树干含量最低;营养元素含量的排序为Ca〉N〉P。2）林地土壤有机质、N和P含量随龄级增加呈明显增长趋势,植被恢复能明显加快土壤肥力的提高。3）20-40 a栓皮栎人工林营养元素积累量为2764.58-3689.38 kg/hm^2,年存留量为89.88-138.17 kg/（hm^2·a）,归还量为229.80-262.06 kg/（hm^2·a）。随龄级增加,营养元素储存总量随之升高,而存留量反而降低;吸收量和归还量呈现先升高后降低的趋势;不同营养元素的储存量、吸收量、归还量和存留量的大小排列次序均为Ca〉N〉P。4）循环系数和周转时间随龄级增加而升高,利用系数则呈现下降趋势;各元素之间Ca的周转时间最长（12.73-16.19a）,利用系数最小。 相似文献
8.
为了解刺槐人工林养分循环特征,以太行山丘陵区刺槐人工林为研究对象,采用样地标准木收获法,对其生物量和养分循环进行研究。结果表明：1）刺槐林乔木层总生物量为39.87 t/hm^2,各器官生物量排序为树干〉树根〉树皮〉树枝〉树叶,树干所占生物量比例最大,叶生物量最小。2）3种元素在各器官中含量表现出较大差异,在树干、树根和树皮中的含量大小排序是N〉Ca〉P,枝、叶中含量排序为Ca〉N〉P。3）各器官营养元素积累量、年存留量分配关系为树干〉树叶〉树枝〉树根〉树皮,林分3种营养元素积累量为633.20 kg/hm^2,积累量和年存留量大小排序为Ca〉N〉P,Ca积累量最多（368.36 kg/hm^2）,P最少（18.19 kg/hm^2）,N居中（276.65 kg/hm^2）。4）凋落物营养元素年归还量为286.52 kg/hm^2,3种营养元素年归还量大小排序为Ca〉N〉P,Ca最高（196.48 kg/hm^2）,分别是N和P的2.31倍和40.26倍。5）刺槐人工林吸收系数排序为N〉P〉Ca,富集系数为N〉P〉Ca,刺槐对N吸收系数、富集系数均高于P、Ca,利用系数、循环系数排序是Ca〉N〉P,Ca周转时间最短（1.87 a）,P最长（3.73 a）,N居中（3.25 a）。 相似文献
9.
温肇穆 《广西农业生物科学》1990,(2)
本文报道广西龙胜县里骆林区24～28年生杉木林林内和林外降水的养分含量及其变化。林外雨的元素含量,以kg/ha·a表示,N是12.972,P 0.289,K 7.249,Ca 9.154,Mg 3.676。乔木层的元素淋溶量,以kg/ha·a表示,N是10.715,P 0.249,K 9.420,Ca 8.675,Mg 9.574。N,P,K的淋溶量与它们在杉木冠层中的积累量呈直线相关;K,Ca,Mg的淋溶量与林内降水量呈直线相关。降水淋溶是K和Mg归还的主要途径。 相似文献
10.
秦武明 《广西农业生物科学》2008,27(3):270-275
研究了广西高峰林场11年生（近熟林）马占相思人工林10种营养元素生物循环的特点。结果表明：（1）马占相思不同器官营养元素含量以树叶（叶状柄）为最高,树干最低;各器官中大量营养元素含量以N最高,其次是Ca或K,然后是Mg,P最低;微量元素含量则以Mn和Fe最高,其次是Zn和B,Cu最低;（2）林分营养元素贮存量为2609．28kg／hm^2,乔木层、灌木层、草本层和凋落物层分别占83．95％、4．43％、1．71％和9．91％,林木中不同器官营养元素贮存量排序为干材〉树枝〉树根〉干皮〉树叶．（3）林分年吸收量、归还量、存留量分别为388．47、195．51和192．96kg／（hm^2·a）,10种元素的循环系数为0．39～0．78,循环速率依次为Mn〉Zn〉Mg〉P〉Ca〉Fe〉N〉Cu〉K〉B。 相似文献
11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响 总被引：2，自引：2，他引：0
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions. 相似文献
13.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
14.
Thomas Larsen Jesper Luxhøi Jakob Magid Lars Stoumann Jensen Paul Henning Krogh 《Biology and Fertility of Soils》2007,44(1):59-68
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization
and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition
with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the
decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots
with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass,
soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration,
N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially
(<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation
in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils,
indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but
the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation
for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community
performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea. 相似文献
15.
《中国生态农业学报》2014,(6)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
16.
《中国生态农业学报》2014,(7)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
17.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
18.
I.L. Boyd 《Biological conservation》2010,143(7):1664-1674
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options. 相似文献
19.
Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage 总被引：1，自引：0，他引：1
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate. 相似文献
20.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献