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1.
Temporal variation in nutrient concentrations of Scots pine (Pinus sylvestris L.) needles was studied during a three‐year period in three stands of differing stages of development. Concentrations of N, P and K varied significantly between years; this variation was related to differences in needle dry weight. Concentrations of all measured nutrients (N, P, K, Ca, Mg, Mn, Cu, Zn, Fe, B) and Al varied between seasons; this variation was related to nutrient mobility and the annual physiological cycle. Concentrations of the mobile nutrients N, P and K decreased in spring and early summer during shoot and needle elongation and increased in late summer and autumn during needle senescence and litterfall. Concentrations of Mg, Cu, Zn and B followed somewhat similar patterns. The poorly mobile nutrients Ca, Mn and Fe accumulated gradually in needles during each growing season. Needle nutrient concentrations were stable during the nonactive period.  相似文献   

2.
Retranslocation of N, P, K, Ca, Mg, Mn, Fe, Zn, Cu and Ni within the foliage of Scots pine (Pinus sylvestris L.) was studied during autumnal needle senescence along a heavy-metal pollution gradient in western Finland. The stands were located at distances of 0.5 (Har 0.5), 4 (Har 4) and 8 km (Har 8) to the southeast of a copper-nickel smelter at Harjavalta. A background study stand was located at H?meenkangas (H?m), 60 km northeast of the smelter. During needle senescence, the mobile nutrients N, P and K decreased by 67-88% and needle dry mass decreased by 31-43%. Retranslocation of P and K was less efficient in the stand nearest the smelter (Har 0.5) than in the other stands. During needle senescence at stand Har 0.5, heavy metal content either decreased slightly (Zn, Ni) or increased (Fe, Cu), whereas in the background study stand, retranslocation efficiency of Cu was 75%. Net throughfall (the amount of a nutrient in throughfall minus the amount in open precipitation) was higher in stand Har 0.5 than in stand Har 8 for all of the elements measured, except N and P which were intercepted by the canopy. In stand Har 8, deposition of S, Cu and Ni was intercepted by the canopy, and net throughfall of Fe and Zn was very low. In contrast, S and heavy metal contents of net throughfall in stand Har 0.5 were greater than the decrease in these elements in the needles indicating that accumulation on needle surfaces and subsequent wash-off accounted for a major part of the fluxes. Furthermore, the Cu content in net throughfall during the senescence period was higher than the original Cu content of the needles in July, providing additional evidence that much of the needle Cu content was comprised of dry deposits of Cu on the needle surface.  相似文献   

3.
The amount and nutrient content of the above-ground litterfall was followed for 9 years in an unfertilized, PKMgB and NPKMgB fertilized Scots pine stand growing on a drained ombrotrophic bog in eastern Finland. The annual litterfall on unfertilized plots was 1995 kg ha−1, of which needles accounted for 74%. The effective temperature sum (threshold value + 5°C) explained 99% of the annual variation in the amount of needle litterfall when the data from one atypical year were excluded from the analysis. Nutrient concentrations were, except for Fe, higher in needle litter than in the other litterfall fractions. Nitrogen, P and K concentrations were low in autumn, and those of Ca and Mn high, possibly owing to variation in the mobility of elements during senescence. The annual litterfall input of N to the soil was 12.4 kg ha−1, and the corresponding values for P and K were 0.08 kg ha−1 and 1.81 kg ha−1, respectively. Fertilization reduced needle litterfall in the first year after treatment, but had no effect thereafter. The amount of other litterfall fractions was not affected by fertilization in any of the 9 years of the study. Nitrogen, P, K and B concentrations increased in the needle litter after both fertilization treatments. The results indicate long-term cycling of fertilizer nutrients on the site.  相似文献   

4.
Nutrient retranslocation from existing foliage of singleleaf pinyon pine (Pinus monophylla Torr. & Frem.) did not meet the nutrient demands of new needles on the same branch. Singleleaf pinyon pines, with an average age of 177 years, located at an elevation of 2300 m on a ridge in The Sweetwater Range in Nevada, USA retained needles for 18 or more years and increased needle number per branch by 17-18% annually. With age, needles gained weight and accumulated Ca, Mg, Fe, Zn, P, and Mn. The amount of N per needle showed no consistent trend with needle age. Only Cu and K declined in concentrations and amounts with needle age and these differences were not statistically significant. Retranslocation of nutrients at needle abscission could provide only 2 to 13% of the N, P, K, Fe, Cu, and Mg required by new needles. We conclude that nutrient capital in existing foliage constitutes a long-term nutrient reserve for the tree rather than a mobile nutrient pool.  相似文献   

5.
Albaugh TJ  Allen HL  Fox TR 《Tree physiology》2008,28(7):1083-1098
We quantified nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) content, use (nutrient amount for one growth year), retranslocation (nutrients recycled before foliage senescence), uptake (use minus retranslocation), volume production per unit of uptake and fertilizer-uptake efficiency (percent applied taken up) in a 2 x 2 (nutrient and water) factorial experiment replicated four times in an 8-year-old loblolly pine (Pinus taeda L.) stand growing on a nutrient-poor sandy soil in Scotland County, North Carolina, USA. Over 14 years, we applied 1140, 168, 393, 168 and 146 kg ha(-1) of elemental N, P, K, Ca and Mg fertilizer, respectively, and an average of 710 mm year(-1) of irrigation. All plots received complete vegetation control. Fertilization about doubled tissue N, P, K and Mg contents at age 21, whereas irrigation resulted in smaller increases in nutrient contents. Maximum annual uptake was 101, 9.3, 44, 37 and 13 kg ha(-1) year(-1) and volume production per unit of nutrient uptake was 0.35, 3.5, 0.66, 1.1 and 3.1 m(3) kg(-1), for N, P, K, Ca and Mg, respectively. Irrigated plots had greater volume production per unit of N, P, K and Mg uptake than control plots, likely because irrigation allowed photosynthesis to continue during dry periods. Fertilized plus irrigated plots had less volume production per unit of these elements than the fertilized plots either because nutrient uptake exceeded the requirement for optimum growth or because available water (rainfall plus irrigation) was insufficient for the leaf area achieved with fertilization. At age 19, fertilizer-uptake efficiencies for N, P, K, Ca and Mg were 53, 24, 62, 57 and 39%, respectively, and increased with irrigation to 68, 36, 78, 116 and 55%, respectively. The scale of fertilizer uptake was likely a result of low native site nutrient availability, study longevity, measurement of all tissue components on site, a comprehensive assessment of coarse roots, and the 3-m rooting depth. Ecosystem nitrogen retention (applied nitrogen found in living plant material, litter fall and soil to 150-cm depth) was estimated at 79% at age 17, a value that would likely be greater when including soil nitrogen to rooting depth and calculating retention at age 21 when the study ended. The ecosystem retention value provides evidence that intensive site resource management can be accomplished with low likelihood of applied materials moving offsite.  相似文献   

6.
Three stand types on drained wetlands, all 31 years old, were studied. The stands were: (1) Scots pine, unfertilized; (2) Scots pine, fertilized; and (3) Norway spruce, fertilized. Amounts of nutrients (N, K, Ca, Mg, P, S, B, Fe, Mn, Zn, Cu) in above-ground biomass for all three stand types could be simulated precisely by a curvilinear regression model, with stand volume on bark as regressor. Net H+ production of the fertilized pine was estimated to be 661 mol H+ ha−1 year−1 from establishment to 31 years of age. The corresponding value for spruce was 1232 mol H+ ha−1 year−1. Atmospheric inputs to the pine and spruce sites were 695 and 516 mol H+ ha−1 year−1, respectively. Atmospheric input of N was 2.3 and 1.3 times the accumulation in the biomass of unfertilized and fertilized pine, whereas the value for spruce was 0.7. The corresponding ratios for S were 43, 19, and 11.  相似文献   

7.
An investigation of wildfire effects on mineral nutrition of Jeffrey pine (Pinus jeffreyi Grev. & Balf.) along with species comparisons of the nutrition of unburned specimens of this pine to those of unburned California white fir (Abies concolor var. lowiana [Gord.] Lemm.) were conducted in an eastern Sierran mixed conifer stand. Foliar Fe and Mn concentrations were frequently higher and Al was consistently so in burned than in the unburned pine as assessed in six sampling periods distributed over more than two postfire growing seasons while base cation/metallic element molar ratios consisting of Ca/Al, K/Al, K/Mn, Ca/Fe, Mg/Fe, K/Fe, and Ca/Zn were often lower in the former. Foliar N, P, Fe, Zn, and Cu were frequently higher in unburned pine than unburned fir while the reverse proved true concerning K, Ca, Mn, B, and Al; and likewise several molar ratios involving Al and Mn were higher in the former while several involving Fe, Zn, and Cu were higher in the latter. At midstudy, mineral soil in the burned stand portion had lower K but higher S, Mn, and Zn than that in the unburned portion, and the former had several molar ratios that were lower as well.  相似文献   

8.
Spatial and temporal variation of N, P, K, Ca, Mg, Mn, Zn, B and Al concentrations in Scots pine (Pinus sylvestris L.) bark and stemwood was studied in three stands at different stages of development. Concentrations of the mobile nutrients N, P and K increased in stemwood and inner bark towards the youngest tissues vertically towards the top of the stem, and horizontally from the pith to the youngest annual rings. The concentrations of Ca, Mg, Mn and Zn were greatest in the oldest tissues and decreased horizontally towards the youngest annual rings. There was a slight increase of most nutrients near the divide between sapwood and heartwood. Seasonal nutrient variation was greatest in the inner bark. The highest nutrient concentrations occurred in winter and spring. Concentrations also varied with stand age, especially in the inner bark, being lowest in the oldest stand.  相似文献   

9.
福建柏人工林养分积累与分配的研究   总被引:4,自引:2,他引:4       下载免费PDF全文
1997年对安溪半林国有林场福建柏人工林的养分积累进行了研究。在连续坡面上福建柏人工林叶的N、P、K含量随坡位升高而降低 ,Ca、Mg、Fe、Cu、Zn则相反 ;养分积累量随坡位升高而缓慢下降。在生长过程中叶的N、P含量随年龄增大而降低 ,Ca、Mg则相反 ,K含量相对稳定 ;10年生、2 0年生时林木叶的养分积累量占全树的比重最大 ,由大到小的顺序为叶、根、干、枝、皮 ,而 30年生时林木根的养分积累量占全树的比重最大 ,由大到小的顺序为根、干、叶、枝、皮 ;营养元素的积累总量随年龄的增大而增加。在不同生长阶段 ,养分的积累与分配有所不同  相似文献   

10.
贵州都匀马尾松种子园针叶DRIS营养诊断分析   总被引:1,自引:0,他引:1  
通过对都匀1.5代无性系种子园20年生马尾松针叶中N、P、K、Ca、Mg、Cu、Zn、Fe、Mn、B等营养元素含量变化的测定和分析,初步筛选出N/P、K/N、Ca/N、Mg/N、N/Cu、zn/N、N/Fe、K/P、Ca/P、P/Mg、P/Cu、P/Zn、Fe/P、K/Ca、K/Mg、K/Cu、K/Zn、Fe/K、Ca/Mg、Ca/Cu、Ca/Zn、Fe/Ca、MgJCu、Zn/Mg、Fe/Mg、Zn/Cu、Fe/Cu、Fe/Zn共28对元素比值为重要参数,对贵州都匀马尾松种子园针叶作DRIS营养诊断分析。结果表明,该地区马尾松针叶内Mn含量过高,平均值为767.01mg/kg,而B含量较低,仅为12.95mg/kg,马尾松的需肥顺序为Cu〉P〉Zn〉Mg〉Ca〉N〉K〉Fe。  相似文献   

11.

Key message

Stand density has a positive effect on C, K and Mg concentration in needle litterfall and a negative one on C, N, Ca, K, Mg, P, S, Zn, and Cu release from needle litter. Consequently, forest management practices such as thinning decrease nutrient concentration in needle litterfall and accelerate nutrient release from decomposing needles in Pinus halepensis plantations in Spain.

Context

Silvicultural practices usually include stand density reduction resulting in changes in litterfall and litter decomposition rates. Little is known about the effect on nutrient concentrations in litterfall and nutrient release during decomposition even when this is the main path of nutrient return to soils.

Aims

The aims of the study are to evaluate the seasonal pattern of nutrient concentration in litterfall, to study how nutrients are released from needle litterfall during decomposition, and to assess whether local basal area of the stand affects nutrient concentration of litterfall and nutrient release during litter decomposition.

Methods

Eight plots were established on each of four stands covering the widest range in local basal area. A littertrap and 15 litterbags were placed on each plot. Periodically, needle litterfall and litter contained in the litterbags were analyzed for C, N, Ca, K, Mg, P, S, Fe, Cu, Mn, and Zn.

Results

Local basal area had a positive effect on C, K, and Mg concentration in needle litterfall and a negative effect on the release of all the nutrients studied but Fe and Mn during the first 2 years of litter decomposition.

Conclusion

Density management of stands has an impact on nutrient cycling, reducing nutrient concentration in needle litterfall, and accelerating nutrient release during decomposition.
  相似文献   

12.
Zusammenfassung Die Gelbf?rbung von Fichten im Südschwarzwald betrifft vor allem die ?lteren Nadeln; der jüngste Nadeljahrgang ist jeweils grün. Wir untersuchten die zeitliche Entwicklung der Vergilbung durch Chlorophyll- und Elementanalysen. Die Vergilbung der letztj?hrigen Nadeln setzt mit dem Knospenaustrieb im Sp?tfrühjahr ein und ist mit einer starken abnahme der Gehalte an Mg und Zn gekoppelt. N, P, K, und S ver?ndern sich nur wenig. Fe und Al, weniger stark Ca und Mn, nehmen mit dem Nadelalter zu. Cu, Pb und Cd zeigen keine Korrelation mit dem Vergilbungsgrad Ein Anstieg des Chlorophyllgehaltes ist nur schwach ausgepr?gt. Aus dem zeitpunkt des Vergilbens und den Ver?nderungen der Elementgehalte schlie?en wir, da? Mobilisierung und Verlagerung von unzureichend angebotenen N?hrelementen (Mg, Zn) die Vergilbung der Nadeln ma?geblich beeinflussen.
Chronological change in chlorophyll and element contents in the needles of a yellow-chlorotic spruce stand
Summary The yellow discoloration of spruce in the southern Black Forest primarily affects the older needles; the current year's needles remain green.We investigated the chronological development of yellowing through chlorophyll and element analyses. The discoloration of last year's needles begins at bud burst in late spring and occurs along with a great decrease in the contents of Mg and Zn. N, P, K. and S are scarcely altered. Fe and Al, less so Ca and Mn, increase with needle age. Cu, Pb, and Cd show no correlation with the degree of yellowing. An increase in chlorophyll content is only weakly pronounced. From the onset of yellowing and the changes in element contents we conclude that mobilization and translocation of the deficient nutrient elements (Mg, Zn) decisively influence needle discoloration.
  相似文献   

13.
大气污染条件下马尾松针叶营养元素变化的研究张萍,杨光滢,李柏忠关键词大气污染,马尾松,营养元素大气污染条件下森林衰亡的研究,自70年代中期以来为国内外学者所重视[1~3];对酸性降水与马尾松林衰亡的研究指出,酸雨、酸雾等酸性降水,加上SO2等酸性干沉...  相似文献   

14.
云南引进葡萄柚品种叶片营养分析   总被引:2,自引:0,他引:2  
对引种于云南省普文县的9个葡萄柚品种的叶片营养进行了分析,结果表明,(1)葡萄柚叶片中P与K、Mn、Zn呈极显著正相关关系;K与Mg、Mn、Zn显著相关;Ca与Mg、Mn、Fe呈显著或极显著相关;Mg与Mn、Fe分别呈显著、极显著负相关;Mn与Zn呈极显著正相关,N与Mn呈显著负相关。(2)叶片中只有氮、铁含量适宜,磷、钾、锌含量过高,钙、镁、锰含量有不同程度的缺乏。  相似文献   

15.
灰木莲人工林营养元素分配及其积累特征   总被引:1,自引:0,他引:1  
对南宁市46年生灰木莲人工林的9种营养元素(N、P、K、Ca、Mg、Fe、Mn、Zn和Cu)的含量、积累量、年净积累量及其分配特征进行了研究。结果表明:灰木莲不同组分的营养元素含量大致为树叶>树皮>树根>树枝>干材。大量元素N、K在树根中的含量最高,P、Mg在树叶中的含量最高,而Ca则在树皮中含量最高;微量元素在各组分中的含量则以Mn最高,Fe、Zn次之,Cu最低。灰木莲人工林营养元素积累总量为1 948.78 kg/hm2,其中乔木层的营养元素积累量为1 715.22 kg/hm2,占林分营养元素积累总量的88.02%;草本层为74.33 kg/hm2,占总积累量的3.81%;灌木层为83.19 kg/hm2,占总积累量的4.26%;凋落物层为76.04 kg/hm2,占总积累量的3.90%。灰木莲人工林营养元素年净积累量为37.32 kg/(hm2·a),各组分营养元素年净积累量排列顺序为干材>树根>树皮>树叶>树枝。  相似文献   

16.
赵登科 《林业调查规划》2011,36(1):35-38,41
对不同月份红锥叶片中营养元素含量的变化及其结构进行研究,结果表明,叶片中N、P、K、Ca、Mg、Mn、Fe、Cu、Zn营养元素含量呈季节性变化,普遍地在生长初期(春季)较高,生长旺期(夏季)最低,而秋冬季生长缓慢时由于积累所致而略有回升;叶片中常量元素含量以N、K、P较高,依次排序为:N〉K〉P〉Mg〉Ca,微量元素含量以Mn、Fe为高,依次排序为:Mn〉Fe〉Zn〉Cu,N、P、K、Ca、Mg、Mn、Fe、Zn、Cu比例为:7.40∶1.00∶5.96∶0.30∶0.51∶1.10∶0.16∶0.05∶0.01;根据研究结果及南方山地的土壤特点,红锥人工幼林的施肥时间宜在春季或春夏之交季节,在肥种及配比上,应在施用大量元素N、P、K、Mg、Ca的基础上配施微肥Zn,配比为N∶P∶K∶Ca∶Mg∶Zn=7.40∶1.00∶5.96∶0.30∶0.51∶0.05.  相似文献   

17.
对冰冻灾害前后湖南湘潭锰矿矿区废弃地的栾树、杜英混交林生态系统的地表水、土壤、林木及死地被物的养分含量进行对比研究.结果表明:冰冻灾害后,林地地表水的pH值、电导率、溶解氧、K、Ca、Mg含量明显减少,Zn、Mn、Pb含量显著增加;林内土壤含水量、全P、全K含量显著增加,速效N、速效P、速效K含量明显减少,微量元素Cu、Pb、Co含量增加,Fe、Zn、Mn、Cd、Ni含量减少;林木枝、叶、干中含水量均显著减少,树干中N、P、Ca、Mg、Cu、Zn、Mn、Cd、Ni、Pb、Co含量增加,树枝和树叶中P、K、Mg减少,而Cu、Fe、Zn、Mn、Cd、Ni、Pb、Co含量却增加;林地上的死地被物中K、Mg在各组分(未分解、半分解、已分解)含量降低,Cu、Fe、Mn、Ni、Co含量增加.可为突发性自然干扰对植物生命活动的影响及抗御机理的研究提供基础数据.  相似文献   

18.
油茶林果实成熟期养分分配特征   总被引:1,自引:0,他引:1  
以常宁市10年生油茶作为试材,对油茶养分分配规律、油茶林土壤养分与树体各器官营养元素含量的相关性进行研究,旨在为油茶营养诊断以及配方施肥提供科学依据。结果表明:油茶各器官中,大量元素含量由高到低排序依次为N、Ca、K、Mg、P,微量元素含量由高到低排序依次为Mn、Fe、Pb、Zn、Cu、Cd;土壤大量元素含量由高到低排序依次为Ca、N、K、P、Mg,微量元素含量由高到低排序依次为Fe、Pb、Zn、Cu、Mn、Cd。土壤养分含量与油茶各器官养分指标具有不同程度的相关性,与油茶干的养分含量相关性最为紧密;土壤N、Zn、Mn、Pb、K含量与油茶植株养分元素含量的关系最为紧密;土壤Mn与油茶各器官Mn元素含量均呈现正相关;土壤N与油茶干中N含量呈现极显著相关;土壤Cd元素含量和油茶各器官中Cd元素含量多存在负相关性。  相似文献   

19.
The impacts of different methods of mechanical site preparation (MSP) on performance and foliar nutrition of planted white spruce (Picea glauca (Moench) Voss) seedlings were examined at two mixed-wood boreal forest sites (Judy Creek, Fox Creek) in Alberta, Canada. The treatments included three types of MSP: disc trench, ripper plough, and bladed, the latter including thin and thick microsites (based on depth of remaining organic matter); as well as a harvested-control (no MSP). Seedlings were planted in June 1991, four months after MSP, and foliar N, P, K, Ca, Mg, S, Mn, Fe, and Al were assessed in the second and third growing seasons (13, 25, and 28 months later). Nutrient concentration and relative (among treatments) foliar nutrient content scaled up to the level of the whole seedling were examined. Following analysis of variance, significant responses were interpreted using vector analysis. MSP did not significantly affect seedling survival, height or unit needle weight. There was a non-significant trend of higher foliar biomass for seedlings in MSP areas than for control seedlings. Overall, the impact of MSP on foliar nutrient status on these sites was minimal. The only consistent positive effect of MSP on seedling nutrition was increased foliar Mg concentrations in blade-thin sites at Fox Creek. Indications of possible negative impacts of MSP include: increased Fe and Al concentrations in MSP areas at both sites; reduced P and K concentrations at both sites; and reduced Mn concentration and content at one site. The ripper treatment had the greatest positive effect on foliar nutrient status (P, K, Mn concentration). Blading (particularly blade-thin) resulted in the lowest concentrations of foliar P, K and Mn and the greatest increases in foliar Fe and Al.  相似文献   

20.
Effects of elevated CO2 concentration ([CO2]) on carbon assimilation and needle biochemistry of fertilized and unfertilized 25-30-year-old Scots pine (Pinus sylvestris L.) trees were studied in a branch bag experiment set up in a naturally regenerated stand. In each tree, one branch was enclosed in a bag supplied with ambient [CO2] (360 micromol mol(-1)), a second branch was enclosed in a bag supplied with elevated [CO2] (680 micromol(-1)) and a control branch was left unbagged. The CO2 treatments were applied from April 15 to September 15, starting in 1993 for unfertilized trees and in 1994 for fertilized trees, which were treated with N in June 1994. Net photosynthesis, amount and activity of Rubisco, N, starch, C:N ratio and SLA of needles were measured during the growing season of 1995. Light-saturated net photosynthetic rates of 1-year-old and current-year shoots measured at ambient [CO2] were not affected by growth [CO2] or N fertilization. Elevated [CO2] reduced the amount and activity of Rubisco, and the relative proportion of Rubisco to soluble proteins and N in needles of unfertilized trees. Elevated [CO2] also reduced the chlorophyll concentration (fresh weight basis) of needles of unfertilized trees. Soluble protein concentration of needles was not affected by growth [CO2]. Elevated [CO2] decreased the Rubisco:chlorophyll ratio in unfertilized and fertilized trees. Starch concentration was significantly increased at elevated [CO2] only in 1-year-old needles of fertilized trees. Elevated [CO2] reduced needle N concentration on a dry weight or structural basis (dry weight minus starch) in unfertilized trees, resulting in an increase in needle C:N ratio. Fertilization had no effect on soluble protein, chlorophyll, Rubisco or N concentration of needles. The decrease in the relative proportions of Rubisco and N concentration in needles of unfertilized trees at elevated [CO2] indicates reallocation of N resources away from Rubisco to nonphotosynthetic processes in other plant parts. Acclimation occurred in a single branch exposed to high [CO2], despite the large sink of the tree. The responses of 1-year-old and current-year needles to elevation of growth [CO2] were similar.  相似文献   

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