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1.
为给红树林保护区的人工造林及红树林持续发展和保护提供依据,对不同树龄无瓣海桑根际土壤的理化性状和土壤酶活性进行了研究.结果表明,不同树龄无瓣海桑的根际土壤为偏酸性至中性(pH6.70~7.04),呼吸速率均较高(>112 mg·kg-1·h-1).根际土壤有机质的含量和含水量随着树龄增加而增加,而微生物量碳、总氮、总磷的含量都在7a树龄达到最高值.随后则随树龄增加而减少,表明7a树龄的无瓣海桑根际土壤的肥力最高,随后随树龄增加而降低.无瓣海桑根际土壤的脲酶、纤维素酶和β-葡糖苷酶的活性变化和微生物量碳、总氮、总磷含量的变化趋势类似,在第7年达到最高值,随后则随树龄增加而减少,表明7a树龄的无瓣海桑正处于生长的高峰期.根际微生物代谢活跃,和氮素营养、碳素营养的转化有密切关系的土壤酶活性达最大值.而磷酸酶和芳基硫酸酯酶的活性随着树龄增加而增加.脱氢酶的活性在不同树龄无瓣海桑间无显著性差异.相关性分析结果表明,除脱氧酶外,土壤酶活性和总氮、总磷、微生物量碳等土壤肥力指标多呈极显著的正相关.  相似文献   

2.
研究了深圳福田红树林无瓣海桑 +海桑人工林群落的Ca、Mg、Na元素的吸收、分布、累积和循环。结果表明 ,该群落植物现存量中 ,库存Ca、Mg、Na总量分别为 2 5 975 4 6、10 332 4 6、115 832 16mg·m-2 ,其中地下部分分别为 86 38 93、6 342、894 99 0 1mg·m-2 。该群落Ca、Mg、Na元素生物循环为 :年吸收量分别为 9337 6 2 6、36 73 318、5 0 2 0 3 5 4 7mg·m-2 ,年归还量分别为 4 32 6 96、16 79 2 97、11792 3474 8mg·m-2 ,年存留量分别为 5 0 10 6 6 6、1976 0 2 8、384 11 2 0mg·m-2 ,周转期分别为 :7a、7a、10a。其中Ca、Mg的循环比Na要快  相似文献   

3.
盐胁迫对青钱柳根部离子分布及幼苗生长的影响   总被引:3,自引:0,他引:3  
在0、1、3和5 g·L-1NaCl处理下,采用X-射线微区分析法对安徽黄山、江西九江及云南昆明3个种源青钱柳的幼苗根部离子分布及幼苗生长变化进行分析.结果表明:在3或5 g·L-1 NaCl胁迫下,根部组织中Na 、Cl-的相对含量增加,K 、Ca2 、Mg2 相对含量降低;随着盐浓度增加,根部表皮和皮层中的Na 含量增加,而Cl-在根部中柱和皮层中的相对含量明显增加.根部组织中的离子失衡,K /Na 和Ca2 /Na 值减小,Na /(K Na Ca2 Mg2 )值增大;根部组织中K /Na 值的减小和Cl-的显著增加导致幼苗存活率降低,幼苗叶面积、苗高、地径及生物量增量减少;供试种源幼苗耐盐能力为黄山>昆明>九江,且青钱柳幼苗的耐盐阈值在1 g·L-1左右.  相似文献   

4.
石漠化石灰土与水土保持植物葛藤化学元素含量特征   总被引:1,自引:0,他引:1  
对贵州花溪区石灰土及水土保持植物葛藤化学元素的含量进行了研究.结果表明:(1)石灰土pH值为7.98,有机质含量为56.60 g·kg-1.全N、全P含量分别为3.56,0.64 g·kg-1,N和P有效率低,速效N仅占全N含量的0.47%.速效P仅占全P的1.46%.全K含量为6.92 g·kg-1.属缺K型土壤.全Ca、全Mg含量分别为15.44、2.74 g·kg-1.(2)微量元素含量依次排序为Fe>Mn>Zn>Ni>Pb>Cu>Co>Cd.全Pb、全Zn、全Cu含量均未超过我国土壤环境质量标准(GB15618-1995)中的3级标准,可以作为林地使用.(3)水土保持植物葛藤体内不同元素含量的差异较大,N、K、Ca元素含量在10 g·kg-1以上,P、Mg元素含量为l~6 g·kg-1,Fe元素在1 000 mg·kg-1以上,Zn、Mn、Pb、Cu元素含量为10~100 mg·kg-1,Cd、Ni元素含量<5 mg·kg-1.(4)葛藤对土壤中N、P、K、Ca、Mg元素的积累能力最强,其次是对Zn、Cd,Cu、Pb元素,而对Mn、Ni、Fe元素的积累能力最弱.研究结果可为石漠化石灰土的植被修复提供理论依据.  相似文献   

5.
三明小湖赤枝栲林地部分矿质元素及土壤理化性质研究   总被引:1,自引:0,他引:1  
分析测定福建三明小湖赤枝栲林部分矿质元素及土壤理化因子 ,结果表明 :该地区土壤 pH值为 4 2 4 ,全N平均含量为 0 0 84 2 % ,全P(P2 O5% )为 0 0 15 5 % ,有机质为 3 7874 %。该地土壤的全N、全P和有机质均不高。该地区土壤Mg元素含量为 6 2 6 0 4 4mg kg-1,Ca为 15 6 5 88mg kg-1,Mn为 80 4 4 4 3mg kg-1,Fe为 2 6 179 6mg kg-1,Co为 3 3335mg kg-1,Ni为12 94 6 7mg kg-1,Cu为 15 2 95 3mg kg-1,Zn为 2 6 9116mg kg-1,Mo为 0 4 6 4 1mg kg-1,Cd为 0 0 4 70mg kg-1,Pb为 9 786 5mg kg-1。土壤矿质元素中 ,Ca、Fe含量偏高 ,Mn含量偏低  相似文献   

6.
对2 a生单种无瓣海桑(Sonneratia apetala)、单种秋茄(Kandelia obvata)和混种无瓣海桑—秋茄(1:1)人工林下土壤理化性质、微生物群落结构、酶活性进行了研究.结果表明,单种无瓣海桑林下土壤pH值最低(5.61±0.08),土壤有机质、总磷、总氮含量在3个群落间均无显著差异;单种无瓣海桑林下土壤蛋白酶、芳基硫酸酯酶和磷酸酶的活性高于其它两种人工林,脲酶、纤维素酶和脱氢酶活性以混种林下最高(分别为190.20±28.49,19.04±4.77和93.21±14.10μg·g-1·h-1),β-葡萄糖苷酶和芳基硫酸酯酶活性在3种人工林下差异不显著;单种无瓣海桑林下土壤中各种脂肪酸含量较高,混种林下土壤的脂肪酸含量最低;典型相关分析表明,蛋白酶活性和土壤pH、总氮含量呈显著负相关(P<0.01),磷酸酶活性与总磷含量呈显著正相关(P<0.01).  相似文献   

7.
三匹虎自然保护区森林土壤理化性质的研究   总被引:6,自引:0,他引:6  
在广西三匹虎自然保护区的森林环境中,于不同的海拔高度带设置了研究其森林土壤理化性质用的9个调查样地,分别采集土样测定其土壤理化性质.结果表明:(1)0~100 cm土层的土壤容重为0.54~1.44 g·cm-3;土壤总孔隙度为53.93 %~72.00 %;土壤通气度为8.28 %~30.55 %;土壤有效贮水量为819.8~1 707.0 t·hm-2.(2)0~40 cm土层土壤的pH值为3.92~4.56;土壤的平均全氮含量和碳氮比分别为1.96 g·kg-1和15.5;土壤的平均全磷和速效磷含量分别为0.62 g·kg-1和1.53 mg·kg-1;土壤的平均全钾和速效钾含量分别为15.25 g·kg-1和97.5 mg·kg-1.(3)三匹虎自然保护区的森林植被在改良其森林土壤的物理特性,提高土壤贮水能力,丰富森林土壤有机质及其N、P、K的含量等,增强土壤涵养水源及肥力上都具有显著的生态功能.  相似文献   

8.
沙棘林改土培肥作用的研究   总被引:6,自引:0,他引:6  
通过对沙棘林土壤及枯枝落叶营养状况的测定,结果表明,不同地区、不同林龄沙棘林地土壤和枯枝落叶营养元素含量差异不大,林地土壤中N全、P全、K全、Ca++、Mg++的含量分别为O.0306%-O.2902%、O.0843%-O.1779%、2.1274%-2.8207%,0.0026%-0.0182%、1.3375%×10-4-6.9385%×10-4;N速、P速、K速、CEC值分别为15.167%-52.267%、2.5747%-l4.l980%、78.8735%-33.4135%、8.1860-25.2595mg/kg。枯枝落叶的N全、P全、K全、Ca++、Mg++分别为1.2696%-11.6694%、0.0576%-0.1283%、0.6250%-0.9823%,2.0643%-3.8821%、0.2187%-0.3143%,且不同土层和林龄表现出不同的规律性;沙棘林地土壤中有机质与N、P、K相关性最为密切。沙棘林地营养含量比相应的农田和草地的高得多,表现出明显的改土培肥作用。  相似文献   

9.
为了研究生态毯覆盖对土壤湿度和养分的影响,首次将生态毯应用于地震滑坡区砾石泥沙堆积区和泥沙堆积区。结果表明:铺设生态毯的土壤含水量均高于裸地的;各层的土壤水分含量随干旱日数的增加呈下降的趋势,生态毯的下降趋势较为平稳;保水效果为椰纤维生态毯秸秆+椰纤维生态毯秸秆生态毯裸地。覆盖生态毯可以提高土壤有机质含量和p H值;土壤速效N、P、K和全N、全P、全K的含量也有一定程度的提高。铺设生态毯能有效固定地震滑坡区的砾石泥沙,改善土壤的水热条件,进而增加根系、微生物的活动和植被有机体的积累,促进枯落物的分解,逐步提高土壤中的养分含量。  相似文献   

10.
在岷江上游干旱河谷岷江柏木幼林地经过连续4 a利用雨季种植绿肥压青,增加土壤肥力,提高水分利用率,促进幼树生长研究。结果表明:(1)种植红豆草的土壤0~40 cm含水量旱季增加3.68 g·kg-1,0~20 cm土壤容重降低0.07 g·cm-3;种植草木樨土壤0~40 cm含水量旱季增加4.18 g·kg-1,0~20 cm土壤容重降低0.05 g·cm-3;种植沙打旺土壤0~40 cm含水量增加2.46 g.kg-1,0~20 cm土壤容重降低0.18 g·cm-3。(2)种植绿肥压青,土壤有机质增加0.37 g·kg-1~0.55 g·kg-1,土壤CaCO3含量下降0.66 g·kg-1~1.36 g·kg-1,有效氮增加4.5 mg·kg-1~18.5 mg·kg-1,有效磷含量增加1.0~3.46 mg·kg-1,CEC比对照增加0.54~0.58mg.100g-1。(3)种植红豆草、草木樨、沙打旺绿肥压青对岷江柏木树高、地径生长有显著的促进作用,尤其种植红豆草的岷江柏木幼树生长最好,高、径生长为对照的1.7倍和1.6倍。  相似文献   

11.
In vitro propagation of a medicinal plant: Tripterygium wilfordii Hook f.   总被引:1,自引:0,他引:1  
In this study a reliable protocol was developed for the establishment of commercial in vitro cultures of Tripterygium wilfordii Hook f.. Juvenile shoots from one-year-old elite plants were used as the source of explants. New axillary shoots were obtained after 30 days of culture on a MS medium supplemented with BAP (2.0 mg·L–1) and NAA (0.1 mg·L–1). The optimal multiplication medium was a modified MS medium supplemented with BAP (1.0 mg·L–1) and NAA (0.1 mg·L–1). This yielded a multiplication rate of 2.4 for each subculture. Slightly more than 92% of shoots rooted when cultured on a modified MS medium containing IBA (0.2 mg·L–1) and acti-vated charcoal (0.5 mg·L–1). Activated charcoal promoted both a strong and a high rooting rate during the rooting phase. Plantlets were transferred to pots for a short acclimatization stage in a greenhouse where 95% of the plantlets survived. This highly reproduci-ble procedure can be adopted for large-scale propagation of T. wilfordii.  相似文献   

12.
Embryo of lilacs (Syringa L) culture in vitro and the rapid propagation were studied. The orthogonal experiments, including the selection of basal medium, embryo age and other factors such as sugar, benzyladenine (BA), naphthalene acetic acid (NAA) and glutamine (Gln), were carried out. The results indicated that the optimal medium for embryo culture was Monnier medium supplemented with NAA (0.001 mg.L^-1), BA (0.1 mg.L^-1), sugar (50 g.L^-1), and Gin (400 mg.L^-1), with a germination rate of 91.7% at least; the optimal embryo age was 50 d; and Gln had significant effects on the germination rate of embryo.Moreover, the optimal medium for subculture was MS BA (2 mg.L^-1) NAA (0.001 mg.L^-1) Gln (0.5 mg.L^-1), with the propagation coefficient of 3.6 at least.  相似文献   

13.
Leaves of fine Populus tomentosa genotype TC152 were used as explants to establish cell suspension lines. The effects of plant growth regulators on callus induction and establishment of cell suspension lines were studied. The callus induction rate was the highest on a MS solid medium supplemented with 1.0 mg·L^-1 2,4-D. A cell suspension line could be obtained by inoculating calli which were not subcultured into a MS liquid medium supplemented with 1.5 mg·L^-1 2,4-D. The best subculture medium was MS + 0.8 mg'L-1 2,4-D + 30 g·L^-1 sucrose with a subculture cycle of seven days.  相似文献   

14.
For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L−1 and 500 mg·L−1 and combinational treatment of scarification with gibberellic acid of 250 mg·L−1 and 500 mg·L−1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous.  相似文献   

15.
We examined the somatic embryogenesis from and histological studies of zygotic embryos of seeds in European Grape 'Moldova' (Vitis vinifera U 'Moldova'). Primary calli were initiated on Nitsch and Nitsch (NN) medium supplemented with 1.0 mg·L^-1 2,4-D and 0.5 mg·L^-1 6-BA. Embryogenic calli were produced upon transfer to a NN medium with 0.5 mg·L^-1 6-BA and 2 mg·L^-1 NAA and somatic embryos were obtained on a half strength MS medium without plant growth regulators. During the somatic embryo germination, an addition of 1.0 mg·L^-1 6-BA in the medium could accelerate somatic embryos to develop into normal plants and increase the conversion rate from 0 to 43.3%. Histological studies of embryogenic calli and somatic embryos demonstrated dynamic changes of proteins and starch grains. The developmental processes of somatic embryos were similar to those of zygotic embryos, including typical epiderma, cotyledon primordium and vascular tissue.  相似文献   

16.
The effects of Timentin and cefotaxime (Cef) on shoot regeneration of the London plane tree (Platanus acerifolia Willd.) and their use for the suppression of Agrobacterium tumefaciens in Agrobacterium-mediated genetic transformation were compared. Shoot regeneration was significantly reduced on the media with Cef at concentrations from 100 to 500 mg·L–1. Timentin showed negative effect on plant regeneration at concentrations of 100 and 500 mg·L–1; however, 300 mg·L–1 Timentin was shown to facilitate shoot r...  相似文献   

17.
Despite growing attention to the role of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in forest nutrient cycling, their monthly concentration dynamics in forest ecosystems, especially in subtropical forests only were little known. The goal of this study is to measure the concentrations and monthly dynamics of DOC and DON in precipitation, throughfall and stemflow for two plantations ofSchima superba (SS) and Chinese fir (Cunninghamia lanceolata, CF) in Jianou, Fujian, China. Samples of precipitation, throughfall and stemflow were collected on a rain event base from January 2002 to December 2002. Upon collection, all water samples were analyzed for DOC, NO3 −N, NH4 +−N and total dissolved N (TDN). DON was calculated by subtracting NO3 −N and NH4 +−N from TDN. The results showed that the precipitation had a mean DOC concentration of 1.7 mg·L−1 and DON concentration of 0.13 mg·L−1. The mean DOC and DON concentrations in throughfall were 11.2 and 0.24 mg·L−1 in the SS and 10.3 and 0.19 mg·L−1 in the CF respectively. Stemflow DOC and DON concentrations in the CF (19.1 and 0.66 mg·L−1 respectively) were significantly higher than those in the SS (17.6 and 0.48 mg·L−1 respectively). No clear monthly variation in precipitation DOC concentration was found in our study, while DON concentration in precipitation tended to be higher in summer or autumn. The monthly variations of DON concentrations were very similar in throughfall and stemflow at both forests, showing an increase at the beginning of the rainy season in March. In contrast, monthly changes of the DOC concentrations in throughfall of the SS and CF were different to those in stemflow. Throughfall DOC concentrations were higher from February to April, while relatively higher DOC concentrations in stemflow were found during September–November period. Foundation item: This study was supported by the Teaching and Research Award program for MOE P.R.C. (TRAPOYT). Biography: Guo Jian-fen (1977-), female, Ph. Doctor in College of Life Science, Xiamen University, Xiamen 361005, P.R. China. Responsible editor: Zhu Hong  相似文献   

18.
Dalbergia sissoo Roxb. is one of the promising multipurpose tree species of South Asia. Most of the plantations of D. sissoo from seeds are facing severe threats due to the die-back disease, which ultimately causes death of this potential tree-species within a few months. Vegetative propagation could avoid the die-back disease. Thirty mother trees of different age-groups of D. sissoo were selected for evaluating the rooting behaviour of branch cuttings from D. sissoo as influenced by auxins (IAA or IBA at 100, 200, 500 mg·L−1), ages of mother trees (10, 4 and 2 years old) and different environment conditions, i.e., different mediums (soil and sand) or light conditions (in shade and open condition). The results show that application of IAA and IBA induced more numbers of cuttings (collected from 10-year-old mother trees) to root compared to control. Branch cuttings of D. sissoo collected from 10-year-old mother trees and planted in soil bed in open conditions had 100.0% of cuttings to root in IAA (100 mg·L−1) and IBA (200 mg·L−1) treatments. Both rooting medium (Soil and sand) influenced significantly (p<0.05) on rooting response of branch cuttings. Soil medium was found to achieve maximum no. of branch cuttings to root, compared to sand medium.  相似文献   

19.
The effect of Thidiazuron (TDZ), basal media and light quality on adventitious shoot regeneration from in vitro cultured stem of Populus albaxP berolinensis were determined to establish a high efficiency shoot regeneration system from stem explants of P. alba~P berolinensis. Stems ofPopulus alba~P berolinensis were collected from cultured shoots in vitro derived from dormancy buds of 3-year-old seedlings. The stem explants were cultured on MS medium containing 0.02-mg·L-1NAA (naphthaleneacetic acid), and 0.1, 0.3, 0.5 and 1.0 mg·L-1 concentrations of TDZ to determine the effect of TDZ on shoot regeneration. Three basal media, i.e. MS, woody plant medium (WPM) and B5, were used to test their influences of different media on adventitious shoot regeneration. Green, red, blue and yellow plastic films in comparison with florescent light as control were used to observe their effects on shoot regeneration. The results showed that differ- ent concentrations of TDZ had an evident influence on shoot regeneration. Lower concentration of TDZ (0.1 mg·L-1) resulted in more ad- ventitious shoot regeneration and higher concentration of TDZ (〉0.1 mg·L-1) inhibited shoot regeneration. Among different media, MS medium exhibited a high efficiency for shoot regeneration, followed by WPM medium, while B5 medium inhibited shoot regeneration. Normal light and yellow light exhibited better effects on shoot regeneration, compared with other light.  相似文献   

20.
Tall fescue (Festuca arundinacea Schreb.) is a cool-season turfgrass used on fairways in golf courses. The object of this study was to develop a more efficient, reliable, and repeatable approach in transforming the grass using Agrobacterium (EHA105), where β-glucuronidase gene (uidA) was used as a reporter and hygromycin phosphotransferase gene (hyg) as a selectable marker. An effective expression of transgene was observed in transforming 2-month-old calli derived from mature seeds (cv. Bingo) cultured on MS medium supplemented with 9 mg·L−1 2, 4-D. A two-step solid medium selection with increasing hygromycin concentration (from 30 to 50 mg·L−1) was used to obtain resistant calli. Transgenic plants have been produced from many independent transformed calli. The presence of functional β-glucuronidase gene (uidA) was detected in hygromycin-resistant calli. Transgenic plants were regenerated and PCR and Southern blot confirmed transgene integration in the tall fescue genome. Biography: QIAN Hai-feng (1973–), male, Ph.D., associate professor in Zhejiang University of Technology.  相似文献   

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