首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 453 毫秒
1.
引种针叶树种矿质元素浓度及季节变化的比较研究   总被引:6,自引:0,他引:6  
以8~10年生的引种试验林为取材对象,分别在1992年4月30日、7月30日、10月30日及1993年1月30日,同时采15个树种当年和1年生针叶,测定N、P、K、Ca和Mg浓度。结果表明,矿质元素浓度种间存在极显著差异。各元素浓度高低总趋势为N>K>Ca>P>Mg。松属中单维管束亚属和双维管束亚属分别表现为富N、Mg和K、P两种元素含量型。树种间Mg元素季节动态存在显著多样性,N、P、K、Ca动态模式松类树种具有极大的相似性。  相似文献   

2.
邹永梅 《江苏林业科技》1998,25(4):20-22,37
用ICP仪分析具有代表性的10个马尾松种源休眠期针叶内矿质营养元素的含量。马尾松休眠期针叶的P和Mg在种源间与种源内个体间的含量差异不显著;Fe,Al两元素在种源间和种源内差异均显著。其中Al含量差异为种源内〉种源间。K,Ca,Mn,Cu,Zn,Si,Na,Ni,Co等9种元素均为种源间差异显著,种源内差异不显著。  相似文献   

3.
通过研究4个种源(塔河、松岭、黑河、带岭)兴安落叶松(Larix gmelinii Rupr.)、多年生枝针叶和当年生枝针叶氮浓度的季节动态和种源差异,结果表明:4种源兴安落叶松多年生枝针叶和当年生枝针叶氮浓度均在8月份达到最大值,7月份出现最小值;当年生枝叶氮浓度仅在生长季初期的6月和7月存在显著差异(P0.05),而多年生枝叶氮浓度在整个生长季内都无显著差异。  相似文献   

4.
我省于1979年开展全国第二次杉木地理种源试验,供试材料来自全国和本省计60个种源,设4个点。经8年试验表明,杉木地理种源间生长量差异极为显著,南岭山地种源显著或极显著优于其它种源。经过综合评定,为我省各生态区选出6─7个优良种源,再按出现频率高低选出全省适用的优良种源4个:融水、大田、锦屏、会同。8年生材积增益幅度30%─70%。  相似文献   

5.
对华山松26个种源针叶生长的研究表明,南、北华山松种源针叶生长节律有显著差异。针叶长度是南方种源大手北方种源,相差近一倍,并呈显著的地理变异规律。  相似文献   

6.
《江西林业科技》1994,(3):35-39,119
我省于1979年开展全国第二次杉木地理种源试验,供试材料来自全国和本省计60个种源,设4个点,经8年试验表明,杉木地理种源间生长量差异极为显著,南岭山地种显著或极显著优于其它种源,经过综合评定,为我省各生态区选出6-7个优良种源,再按出现频率高低选出全省适用的优良种源4个:融水、大田、锦屏、全同。8年生材积增益幅度30-70%。  相似文献   

7.
本文以26个华山松全分布区种源对象,研究了1、2年生枝和叶的含水量,N、P、K、Ca,Mg等元素含蝗地理变异。结果表明:南、北种源含水量无明显差异,其它元素均存在显著差异,并有明显纬向渐规律。N、P、K、和Ca含量北方种源比南方种源高,Mg含量南方种源比北方种源高。1、2年生枝以K含量最高,叶中以N含量最大,各元素在不同组织中,除N、P含量一致,其它均有差异。  相似文献   

8.
杉木地理种源矿质分析及变异规律的研究   总被引:1,自引:0,他引:1  
研究了杉木地理种源间矿质元素(杉木种源针叶灰分中氮、钾、铁、磷、钙、钩等元素百分含量)代谢的差异,及其与地理分布的关系,作为选择优良种源的科学依据。试验测定结果:生长快的种源钾含量高于生长慢的种源,钾、铁两元素百分含量高值区和杉木生长好的中心区基本一致。  相似文献   

9.
《江西林业科技》1994,(3):120-127
研究了杉木地理种源间矿质元素(杉木种源针叶灰分中氮、钾、铁、磷、钙、钠等元素百分含量)代谢的差异,及其与地理分布的关系,作为选择优良种源的科学依据。试验测定结果:生长快的种源钾含量高于生长慢的种源,钾、铁两元素百分含量高值区和杉木生长好的中心区基本一致。  相似文献   

10.
不同营林措施对马尾松针叶养分的影响   总被引:4,自引:0,他引:4  
对设置在贵州龙里、台江以及广西热带林业实验中心的不同施肥、不同密度、不同抚育措施、不同整地方式和不同种源马尾松人工林试验样地内针叶样品的N、P、K、Ca、Mg含量进行分析研究,结果表明,除广西施肥5年后,不同处理间针叶N、Mg两元素含量具有极显著差异外,其余措施对马尾松针叶养分含量的影响均未达到显著差异水平。因此,施肥具有调节马尾松针叶养分含量的作用;而不同造林密度林地内马尾松个体吸收养分的能力相同,则高密度易造成地力的快速衰退,对长期高密度造林的林地,应加以施肥,以维护土壤的持续利用;抚育措施并不影响林木养分的吸收;整地也未对马尾松吸收养分有多大影响;不同种源吸收养分的特点差异不大,因而优良种源加速林地地力的衰退。  相似文献   

11.
Foliar mineral concentration may provide a basis for monitoring the consequences of long-term environmental changes, such as eutrophication and acidification of soils, or increase in atmospheric CO(2) concentration. However, analytical drifts and inter-tree and year-to-year variations may confound environmental effects on long-term changes in foliar mineral concentration. We have characterized the relative effects of these potentially confounding factors on foliar carbon, nitrogen, phosphorus, calcium, potassium, magnesium and manganese concentrations in 118 pure beech (Fagus sylvatica L.) stands, sampled in 1969-71 and 1996-97. Interannual fluctuations of these elements were quantified in a subset of six beech stands monitored for 5 years. Intercalibration between the methods used at each sampling period for nitrogen and phosphorus analyses showed significant, but low, relative differences (0.8 and 3.3% for N and P, respectively). Based on inter-tree variability, elements could be arranged in four groups: C (constant), N and P (low variability), K and Ca (medium variability), Mn and Mg (high variability). Inter-tree coefficients of variation were 2, 6, 8, 15, 18, 22 and 27%, respectively. Year-to-year fluctuations increased in the order N, P, Mg, K, Ca, and Mn coefficients of variation of 4, 4, 7, 9, 11, 15 and 29%, respectively). Between the two sampling periods, foliar N concentration increased 12%, whereas decreases were observed for P (-23%), Mg (-38%) and Ca (-16%). Ratios of N/P, N/K and N/Mg increased by 42, 19 and 77%, respectively. These changes were larger than the interannual variations for P, Mg, N/P, N/Mg and Mg/Ca. Decreasing concentrations of P and cations were particularly marked for trees growing on acidic soils, whereas the positive N trend did not depend on soil type. Both increasing atmospheric CO(2) concentrations and acidification of forest soils could contribute to decreasing P and cation concentrations in foliage. The increase in foliar N concentration with time suggests a nitrogen deposition effect. Whatever the causes of these changes, the large shift in element ratios indicates an accelerating imbalance between nitrogen and cation status.  相似文献   

12.
Balanites aegyptiaca (L.) Delile. is one of the priority indigenous fruit trees for rural communities in the West African Sahel. As part of a participatory tree domestication program in Niger, phenotypic variation in fruit and seed morphology was assessed in four natural populations in eastern Niger. Measured variables were weight of the fruit, seed coat and kernel; length and width of the fruit and seed (25 trees per population, 30 fruits per tree). Derived variables were the tree’s coefficient of variation (CVs) for each measured variable, and two sets of factor scores from principal components analysis of tree means and CVs. ANOVA indicated significant variation in all measured variables due to trees nested in populations. ANOVA and simple linear regression indicated significant geographic variation in some variables: the drier parts of the sample region tended to have heavier fruits and kernels, longer/narrower seeds, and lower within-tree variability in fruit and seed width. Length and width were strongly correlated between fruits and seeds, fruit weight was moderately correlated with seed dimensions, and CVs of fruit weight and width were moderately correlated with the CV of seed width. Some hypotheses for the geographic variation are presented, and some practical implications of the correlations for tree domestication programs are discussed.  相似文献   

13.
Miller SP  Cumming JR 《Tree physiology》2000,20(16):1129-1135
Effects of simulated serpentine soil conditions (elevated Mg:Ca ratio and Ni concentration) on seedlings from populations of Virginia pine (Pinus virginiana Mill.) from serpentine and non-serpentine sites were evaluated in sand culture. We determined (1) how seedlings are affected by elevated Mg:Ca ratio and Ni concentrations, (2) if there are interactive effects between Mg:Ca ratio and Ni concentrations on seedling growth, needle pigment concentrations, and nutrition, and (3) if Virginia pine populations from serpentine areas are edaphic ecotypes. A Mg:Ca ratio of 5 and 50 microM Ni both reduced seedling growth compared with control seedlings grown in the presence of the standard Mg:Ca ratio of 0.5 and no Ni. Interactive effects between Mg:Ca ratio and Ni concentrations were highly significant for growth, foliar pigments, and needle and root elemental concentrations. Nickel-mediated reductions in growth and foliar pigment concentrations were less at the serpentine Mg:Ca ratio of 5 than at the standard (non-serpentine) Mg:Ca ratio of 0.5. Foliar N was reduced by Ni concentrations as low as 10 microM, and foliar and root K, Ca and P concentrations were significantly reduced by Ni concentrations above 25 microM, with greater reductions at a Mg:Ca ratio of 0.5 than at a Mg:Ca ratio of 5. There were no population x serpentine soil factor interactions for seedling growth, foliar pigment concentrations, or nutrition, suggesting that seedlings from trees growing on serpentine soils are not edaphic ecotypes. We conclude that serpentine conditions present at the site of seed collection have not resulted in the selection of edaphic ecotypes of Virginia pine with respect to Mg:Ca ratio and Ni concentration.  相似文献   

14.
In 1998, a fertilizer experiment aiming to investigate the effects of slow-release N, P, K and Mg fertilizer (SILVAMIX Mg NPK®) on a 60-year-old spruce stand with symptoms of yellowing was established. In this paper, trees were selected to investigate the relation between annual diameter increment, yellowing, foliation, needle and soil chemical properties: ten from the fertilized treatment (F), ten green trees from the control (CG) and ten yellow trees from the control (CY). CG and CY trees were growing in close proximity at a distance of only several meters apart under the same soil conditions. In treatment F, increased annual diameter increment, improved foliation, needle Mg concentration, plant-available Mg and P concentrations in the soil and absence of yellow trees were recorded 7 years after a single application of the fertilizer. During the last 15 years, annual growth increment and foliation of CY trees have continuously decreased while relatively stable values were recorded for CG trees and increased for F trees. In 2006, CG and CY trees differed significantly in Mg concentration in needles, foliation, yellowing and annual diameter increment. Although differences in soil chemical properties between CG and CY treatments were not significant, lower concentrations of plant-available Mg2+ and higher concentrations of H+ and Al3+ were found in soils under CY trees. There was a negative correlation between soil concentration of Mg and yellowing, but this correlation was relatively weak, indicating that there is no simple relation between soil and needle concentrations of Mg. In the investigated locality, the “new type” of yellow tree decline has been a long-term gradual process.  相似文献   

15.
Yang SH  Loopstra CA 《Tree physiology》2005,25(8):1063-1073
In developing xylem, gene expression levels vary in different genotypes, at different stages of development, throughout a growing season, and in response to stresses. Commercially important characteristics such as wood-specific gravity are known to differ with seed source. For example, when grown on a common site, the specific gravity of Arkansas loblolly pine (Pinus taeda L.) trees is greater than that of Louisiana loblolly pine, and Texas loblolly pines have a greater specific gravity than loblolly pines from the Atlantic coast. A microarray analysis was performed to examine variation in gene expression among trees from different geographical sources when grown on a common site, and seasonal variation in gene expression in each seed source. We used microarrays containing 2171 expressed sequence tags (ESTs) with putative functions of interest, selected from several loblolly pine xylem partial cDNA libraries and a shoot tip library. Genes with significant variation in expression for each factor were identified. Many genes preferentially expressed in latewood compared with earlywood were for proteins involved in cell wall biosynthesis. Variation in gene expression among trees from the two seed sources in each growing season suggests that there may be more differences between South Arkansas trees and South Louisiana trees in latewood than in earlywood. Variation in gene expression among trees from different regions may reflect adaptation to different environments.  相似文献   

16.
马尾松一代种子园母树营养特点研究   总被引:1,自引:0,他引:1  
对马尾松一代种子园母树的针叶和球果的营养元素含量进行测定、分析、比较,结果表明:马尾松种子园母树对氮、钾、钙、磷养分的需求量较大,针叶中各元素含量由高到低依次为NKCaPMgBMo,球果的养分含量为KNCaPMgBMo;种子园母树的针叶、球果中各营养元素含量波动较大;初步得到种子园母树针叶各营养元素含量适宜范围为:N(10.994~13.414 g/kg),P(1.026~1.430 g/kg),K(6.025~15.842 g/kg),Ca(1.784~5.483 g/kg),Mg(0.845~1.233 g/kg),B(28.417~38.854 mg/kg),Mo(1.743~3.012 mg/kg),可作为推测种子园母树营养元素是否分布正常以及种子园施肥和开展配方施肥试验的参考依据之一。  相似文献   

17.
江西省毛竹笋矿质元素含量区域分异性研究   总被引:1,自引:1,他引:0  
对江西11个设区市毛竹集中分布区的毛竹春笋的矿质元素进行测定分析,结果显示:地区、坡向、海拔和林分类型4个因素对各种矿质元素含量的影响规律相对一致,均没有达到显著水平。林分类型对各矿质元素的含量分异性影响最小,除镁元素外,其他矿质元素的含量均以纯林较高;坡向对灰分及除镁以外的金属元素含量的影响均较大,其中钙、镍、镁均以北坡含量较高,氮和灰分以东坡含量较高;海拔则对氮、磷和镁元素含量的影响较大,其中磷和镁元素均以海拔800m以上含量较高;地区因素在4个因素中排在第二位,对各矿质元素的含量都有较大的影响力,以赣北地区处于较高水平。  相似文献   

18.
Effects of magnesium deficiency and variation in nitrate to ammonium ratio on needle histology and chlorophyll concentration were investigated in current-year and one-year-old needles of clonal Norway spruce trees (Picea abies (L.) Karst.). Six-year-old trees were grown for one year in sand culture with circulating nutrient solutions containing a sufficient (0.2 mM) or a limiting (0.04 mM) concentration of Mg. The nitrogen concentration was not varied (5 mM), but the NO(3) (-)/NH(4) (+)-ratio was adjusted to 0.76 in Mg-sufficient and to 1.86, 0.76 or 0.035 in Mg-limited plants. Visible symptoms of Mg deficiency occurred only in current-year needles, indicating adequate Mg nutrition before the experiment. Under conditions of Mg limitation, chlorophyll and Mg concentrations were lowest in needles of trees supplied with NH(4) (+) as the major nitrogen source and highest in needles of trees supplied with NO(3) (-) as the major nitrogen source. In current-year and one-year-old needles, starch accumulation induced by Mg deficiency was increased when NH(4) (+) was the major nitrogen source. The accumulation of tannin spherules in current-year needles, which occurred in response to Mg deficiency, also increased with decreasing NO(3) (-)/NH(4) (+)-ratios. Deficient Mg supply caused premature aging in tissues of the vascular bundle, as indicated by modifications of the cambium and increased amounts of collapsed sieve cells. The number of collapsed sieve cells was slightly lower in needles grown in a NH(4) (+)-dominated nutrient regime than in needles grown in a NO(3) (-)-dominated nutrient regime. We conclude that was not directly toxic to Norway spruce trees at the applied concentrations. However, effects of Mg deficiency were considerably greater in an NH(4) (+)-dominated nutrient regime than in a NO(3) (-)-dominated nutrient regime.  相似文献   

19.
火炬松人工林林木营养特性的研究   总被引:5,自引:1,他引:5  
费世民 《林业科学》1995,31(4):299-309
通过试验控制,定位观测和养分元素分析测定,定量地研究了莎下蜀林场15年生火炬松人工林林木矿质营养特征。  相似文献   

20.
Bauer G  Schulze ED  Mund M 《Tree physiology》1997,17(12):777-786
Mineral nutrition of Norway spruce (Picea abies (L.) Karst.) and beech (Fagus sylvatica L.) was investigated along a transect extending from northern Sweden to central Italy. Nitrogen (N) concentrations of needles and leaves in stands growing on acid soils did not differ significantly between central Italy and southern Sweden (1.0 +/- 0.1 mmol N g(-1) for needles and 1.9 +/- 0.14 mmol N g(-1) for leaves). In both species, foliar N concentrations were highest in Germany (1.2 mmol N g(-1) for needles and 2.0 mmol N g(-1) for leaves) and decreased by 50% toward northern Sweden (0.5 mmol N g(-1)). Both species showed constant S/N and P/N ratios along the transect. Calcium, K and Mg concentrations generally reflected local soil conditions; however, Mg concentrations reached deficiency values in Germany. Leaf area per unit dry weight varied significantly along the transect with lowest values for Norway spruce recorded in northern Sweden and Italy (3.4 m(2) kg(-1)) and a maximum in central Europe (4.7 m(2) kg(-1)). A similar pattern was observed for beech. Despite the low variation in foliar N concentrations on the large geographic scale, local and regional variations in N concentrations equalled or exceeded the variation along the entire continental transect. Furthermore, nutrient contents (i.e., nutrient concentration x dry weight per needle or leaf) showed a greater variation than nutrient concentrations along the transect. Nitrogen contents of Norway spruce needles reached minimum values in northern Sweden (2.4 micro mol N needle(-1)) and maximum values in Denmark (5.0 micro mol N needle(-1)). The N content of beech leaves was highest in Denmark (242 micro mol N leaf(-1)). At the German site, foliar N content rather than N concentration reflected the seasonal dynamics of foliar growth and N storage of the two species. During foliage expansion, there was an initial rapid increase in N content and a decrease in N concentration. This pattern lasted for about 2 weeks after bud break and was followed by 6 weeks during which dry weight and N content of the foliage increased, resulting in a further decrease in N concentration. During summer, dry weight and N content of mature needles of Norway spruce increased further to reach a maximum in autumn, whereas N concentration remained constant. In spring, reallocation of N from 1- and 2-year-old needles was 1.5 and 1.0 micro mol N needle(-1), respectively. This remobilized N was a major source of N for the development of new needles, which had an N content of 1.5 micro mol N needle(-1) after bud break. The seasonal remobilization of N from old foliage decreased with increasing needle age. Needle N content and dry weight decreased progressively with age (1 micro mol N needle(-1) between age classes 2 and 5), whereas N concentrations remained constant. For Norway spruce, annual stemwood production was correlated with needle N content but not with foliar N concentration or with the total amount of N in the canopy. Interspecific and geographical differences in plant nutrition are discussed on the basis of competitive demands for C and N between growth of foliage and wood.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号