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1.
《热带农业科技》2000,(3)
试验就ＣＯ2 浓度 ( 35～ 4 50ａｍｂｉｅｎｔ,10 0 0或 2 0 0 0 μｍｏｌ/ｍｌ) ,空气交换速率 ( 0 5或 2次 /ｈ)、温度 2 4± 1℃ ,光合光子通量 (ＰＰＦ 140 μｍｏｌ/ ·ｓ,光周期 16ｈ)和相对湿度 ( 70 %～ 80 % )对非洲菊幼苗生长的影响进行调查。外植体 (芽 )取自光合营养微体繁殖的幼苗 ,置于Ｍｕｒａｓｈｉｇｅ和ｓｋｏｏｇ培养基 (不加糖 )培养 35ｄ。结果 ,ＣＯ2 增加使鲜重、干重、高度、叶面积和叶绿素含量显著增加 ,对干物质比率和叶的数量则无明显影响。空气交换速率增加 ,叶绿素含量显著减少 ,而鲜重、干重、高度和叶的数… 相似文献
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毛白杨无性系木材基本密度遗传变异研究 总被引：8，自引：2，他引：6
在现代社会 ,杨树木材无论在实体木材还是纤维产品方面都发挥着越来越重要的作用。许多发达国家对杨属各树种木材材性遗传变异的研究非常重视 ,对美洲山杨 (Ｅｉｎｓｐａｈｒｅｔａｌ.,1 972 ;Ｒｅｄｄｙ ,1 983;Ｙａｎｃｈｕｋｅｔａｌ.,1 983;1 984)、美洲黑杨 (Ｆａｒｍｅｒｅｔａｌ.,1 968;Ｐｏｓｅｙｅｔａｌ.,1 969;Ｏｌｓｏｎｅｔａｌ.,1 985)等杨树树种木材材性的遗传变异都做了较为系统的研究。我国对于杨树材性性状的遗传变异研究起步较晚 ,只对山杨 (张立非等 ,1 993;杨自湘等 ,1 994;顾万春等 ,1 994)以及黑杨派、青杨派一些杨… 相似文献
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加拿大安大略省南部农林系统中碳、氮平衡的研究 总被引：1，自引：0，他引：1
为减缓温室效应对全球气候变化的影响而控制温室气体 (CO2 ,N2 O等 )的排放量 ,这在全球已达成共识。京都议定书 (KyotoProtocol)对发达国家的温室气体排放量做出了限制。加拿大作为发达国家 ,对承担京都议定书的义务有一种紧迫感。他们除了建议森林的固碳作用可作为对工业CO2 的排放进行补偿外 ,还大力发展农林系统 ,将过去认为的温室气体排放源的单纯农田改变成一种吸收CO2 的碳汇———农林系统 (Dixon ,1 995 )。森林的固碳作用不容置疑 ,在全球的碳平衡中森林起了不可替代的作用(Dixonetal.,1 994;Fangetal.,2 0 0 1 )。加拿大是… 相似文献
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由人类活动所造成的大气中温室气体浓度急剧增加而引起的全球气候变暖和环境变化已引起全世界的广泛关注。氧化亚氮(N2O)是仅次于二氧化碳(CO2)和甲烷(CH4)的一种温室气体,在大气中含量较低却十分稳定,具有较大的增温潜能(其单分子的增温潜能是CO2的310倍)和较快的浓度增加速率(以每年0.25%的速率增加)(IPCC,2007)。N2O可吸收红外线,减少地球表面通过大气向外层空间的热辐射,导致地球表面温度增加。N2O能参与大气中许多光化学反应,破坏臭氧层(Crutzen,1970),导致到达地球表面的紫外线明显增加,给人类健康和生态环境带来多方面的危害。 相似文献
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被子植物亚门 ＡＮＧＩＯＳＰＥＲＭＡＥ双子叶植物纲 ＤＩＣＯＴＹＬＥＤＯＮＥＡＥ 桃金娘科 ＭＹＲＴＡＣＥＡＥ肖蒲桃(Ａｃｍｅｎａａｃｕｍｉｎａｔｉｓｓｉｍａ(Ｂｌ.)Ｍｅｒｒ.ｅｔＰｅｒｒｙ),荔枝母(东方);Ｈ(20),Ｄ(60)。尖峰,本岛常见。皮灰棕褐;心材棕红,边材灰褐,生长轮可见;材重硬韧,ｄ(0.81),难加工,较耐腐。供造船、建筑、车辆、家具等。※大果水翁(ＣｌｅｉｓｔｏｃａｌｙｘｃｏｎｓｐｅｒｓｉｐｕｎｃｔａｔｕｓＭｅｒｒ.ｅｔＰｅｒｒｙ),多腺水翁;Ｈ(30),Ｄ(60)。吊罗,本岛南半部常见。皮灰黄(具黑白斑印);木材… 相似文献
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液体深层培养绿僵菌分生孢子的研究 总被引：6，自引：0，他引：6
目前国内外生产绿僵菌分生孢子制剂常用固体发酵法或两相发酵法 ,这些方法生产周期长 ,产品易被污染 ,产量低 ,不能大量满足生物防治的需要。而液体深层培养具有生产周期短 ,产品不易被污染 ,生产率高 ,培养条件易控制等优点 ,倍受人们所推崇。现已知有少数几种昆虫致病丝孢菌 ,如Ａｓｐｅｒｇｉｌｌｕｓｏｃｈｒａｃｅｕｓ (Ｖ啨ｚｉｎａｅｔａｌ.,1 965 )、Ｈｉｒｓｕｔｅｌｌａｔｈｏｍｐｓｏｎｉｉｖａｒ.ｓｙｎｎｅｍａｔｏｓａ (Ｗｉｎｋｅｌｈｏｆｆｅｔａｌ.,1 984)、Ｂｅａｕｖｅｒｉａｂａｓｓｉａｎａ (Ｔｈｏｍａｓｅｔａｌ.,1 … 相似文献
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1 培养基配方 采用ＭＳ培养基配方。1.1 大量元素 ＮＨ4 ＮＯ3,16 5 0ｍｇ/Ｌ ;ＫＮＯ3,190 0ｍｇ/Ｌ ;ＣａＣｌ2 ·2Ｈ2 Ｏ ,4 40ｍｇ/Ｌ ;ＭｇＳＯ4 ·7Ｈ2 Ｏ ,370ｍｇ/Ｌ ;ＫＨ2 ＰＯ4 ,170ｍｇ/Ｌ。1.2 微量元素 ＫＩ ,0 .83ｍｇ/Ｌ ;ＭｎＳＯ4 ·4Ｈ2 Ｏ ,2 2 .3ｍｇ/Ｌ ;ＺｎＳＯ4 ·7Ｈ2 Ｏ ,8.6ｍｇ/Ｌ ;Ｎａ2 ＭｎＯ4 ·2Ｈ2 Ｏ ,0 .2 5ｍｇ/Ｌ ;ＣｕＳＯ4 ·5Ｈ2 Ｏ ,0 .0 2 5ｍｇ/Ｌ ;ＣｏＣｌ2 ·6Ｈ2 Ｏ ,0 .0 2 5ｍｇ/Ｌ。1.3 有机成分 甘氨酸 2ｍｇ/Ｌ ,盐酸硫胺素Ｂ10 .4ｍｇ/Ｌ ,盐酸吡哆素Ｂ6 0 .5ｍｇ/… 相似文献
11.
The effects of shade and soil temperature on growth of Eucalyptus marginata Donn ex Sm (jarrah) seedlings were studied in greenhouse experiments. Plant dry weight and that of all plant parts declined in response to shade, as did root/shoot ratio. Plant leaf area was less in unshaded plants than in plants grown in shade, and specific leaf area increased with shade. Unshaded seedlings had a higher light-saturated rate of photosynthesis, a higher light compensation point and a higher light saturation point than seedlings grown in 70% shade. The relationship between plant dry weight and leaf dry weight was independent of shading, whereas the relationship between plant dry weight and plant leaf area was dependent on shading. Therefore, leaf dry weight may be a better predictor of biomass production than leaf area in forest stands where shade is likely to affect growth significantly. Soil temperature had a significant effect on the growth of all plant parts except cotyledons. Total plant growth and shoot growth were maximal at a soil temperature of 30 degrees C, but root growth had a slightly lower temperature optimum such that the root/shoot ratio was highest at 20 degrees C. Roots grown at 15 degrees C were about 30% shorter per unit of dry weight than roots grown at 20 to 35 degrees C. We conclude that increases in irradiance and soil temperature as a result of overstory removal in the forest will cause significant increases in growth of E. marginata seedlings, but these increases represent a relatively small component of the growth response to overstory removal. 相似文献
12.
Stockplants of Eucalyptus grandis were pruned to a height of 7–10 cm and after 3 weeks were placed in growth cabinets set at a photon flux density (PFD) of 200 μmol m−2 s−1 and red to far-red ratios of 0.4, 0.7, 1.3, 3.5 or 6.5. Experiments tested the effects of light quality on growth and gas exchange of stockplants. Light quality did not affect the total shoot dry weight (DW), root DW or shoot to root ratio of stockplants or their total leaf area. However, there were significant effects of light quality on: (i) plant height, which was greatest at red:far-red (R:FR) ratios of 0.4 and 0.7; (ii) partitioning of DW between leaves and stems, with greater stem DW and less leaf DW at low R:FR ratios (0.4 and 0.7); (iii) partitioning of DW and leaf area between the most dominant shoot and all other (non-dominant) shoots; (iv) specific leaf area, which was greatest at low R:FR ratios. In the above characters, the dominance ratio (ratio of most dominant shoot to sum of all other shoots) was greatest at low R:FR ratios and least at ratios of 3.5 and 6.5. Photosynthetic rate per unit leaf area and leaf chlorophyll concentration significantly increased with increasing R:FR ratio. However, photosynthesis per unit chlorophyll concentration was significantly greater at low R:FR ratios. Generally, light quality had no significant effect on photosynthetic rate per leaf or per unit dry weight, but rates of transpiration, stomatal conductance and water use efficiency increased with an increase in R:FR ratio. These data indicate that compensatory changes in plant morphology and gas exchange caused equality in total dry weight per plant between treatments. The above effects of light quality on dry matter partitioning and gas exchange had important effects on the size, number, morphology and physiology of subsequently collected cuttings for vegetative propagation. 相似文献
13.
Seedlings of five boreal tree species differ in acclimation of net photosynthesis to elevated CO(2) and temperature 总被引：1，自引：0，他引：1
Biochemical models of photosynthesis suggest that rising temperatures will increase rates of net carbon dioxide assimilation and enhance plant responses to increasing atmospheric concentrations of CO(2). We tested this hypothesis by evaluating acclimation and ontogenetic drift in net photosynthesis in seedlings of five boreal tree species grown at 370 and 580 &mgr;mol mol(-1) CO(2) in combination with day/night temperatures of 18/12, 21/15, 24/18, 27/21, and 30/24 degrees C. Leaf-area-based rates of net photosynthesis increased between 13 and 36% among species in plants grown and measured in elevated CO(2) compared to ambient CO(2). These CO(2)-induced increases in net photosynthesis were greater for slower-growing Picea mariana (Mill.) B.S.P., Pinus banksiana Lamb., and Larix laricina (Du Roi) K. Koch than for faster-growing Populus tremuloides Michx. and Betula papyrifera Marsh., paralleling longer-term growth differences between CO(2) treatments. Measures at common CO(2) concentrations revealed that net photosynthesis was down-regulated in plants grown at elevated CO(2). In situ leaf gas exchange rates varied minimally across temperature treatments and, contrary to predictions, increasing growth temperatures did not enhance the response of net photosynthesis to elevated CO(2) in four of the five species. Overall, the species exhibited declines in specific leaf area and leaf nitrogen concentration, and increases in total nonstructural carbohydrates in response to CO(2) enrichment. Consequently, the elevated CO(2) treatment enhanced rates of net photosynthesis much more when expressed on a leaf area basis (25%) than when expressed on a leaf mass basis (10%). In all species, rates of leaf net CO(2) exchange exhibited modest declines with increasing plant size through ontogeny. Among the conifers, enhancements of photosynthetic rates in elevated CO(2) were sustained through time across a wide range of plant sizes. In contrast, for Populus tremuloides and B. papyrifera, mass-based photosynthetic rates did not differ between CO(2) treatments. Overall, net photosynthetic rates were highly correlated with relative growth rate as it varied among species and treatment combinations through time. We conclude that interspecific variation may be a more important determinant of photosynthetic response to CO(2) than temperature. 相似文献
14.
Relatively little is known about the implications of atmospheric CO2 enrichment for tree responses to biotic disturbances such as folivory. We examined the combined effects of elevated CO2 concentration ([CO2]) and defoliation on growth and physiology of sugar maple (Acer saccharum Marsh.) and trembling aspen (Populus tremuloides Michx.). Seedlings were planted in the ground in eight open-top chambers. Four chambers were ventilated with CO2-enriched air (ambient + 283 micromol mol-1) and four chambers were supplied with ambient air. After 6 weeks of growth, half of the leaf area was removed on a subset of seedlings of each species in each CO2 treatment. We monitored subsequent biomass gain and allocation, along with leaf gas exchange and chemistry. Defoliation did not significantly affect final seedling biomass in either species or CO2 treatment. Growth recovery following defoliation was associated with increased allocation to leaf mass in maple and a slight enhancement of mean photosynthesis in aspen. Elevated [CO2] did not significantly affect aspen growth, and the observed stimulation of maple growth was significant only in mid-season. Correspondingly, simulated responses of whole-tree photosynthesis to elevated [CO2] were constrained by a decrease in photosynthetic capacity in maple, and were partially offset by reductions in specific leaf area and biomass allocation to foliage in aspen. There was a significant interaction between [CO2] and defoliation on only a few of the measured traits. Thus, the data do not support the hypothesis that atmospheric CO2 enrichment will substantially alter tree responses to folivory. However, our findings do provide further indication that regeneration-stage growth rates of certain temperate tree species may respond only moderately to a near doubling of atmospheric [CO2]. 相似文献
15.
Temperton VM Grayston SJ Jackson G Barton CV Millard P Jarvis PG 《Tree physiology》2003,23(15):1051-1059
Nitrogen-fixing plant species may respond more positively to elevated atmospheric carbon dioxide concentrations ([CO2]) than other species because of their ability to maintain a high internal nutrient supply. A key factor in the growth response of trees to elevated [CO2] is the availability of nitrogen, although how elevated [CO2] influences the rate of N2-fixation of nodulated trees growing under field conditions is unclear. To elucidate this relationship, we measured total biomass, relative growth rate, net assimilation rate (NAR), leaf area and net photosynthetic rate of N2-fixing Alnus glutinosa (L.) Gaertn. (common alder) trees grown for 3 years in open-top chambers in the presence of either ambient or elevated atmospheric [CO2] and two soil N regimes: full nutrient solution or no fertilizer. Nitrogen fixation by Frankia spp. in the root nodules of unfertilized trees was assessed by the acetylene reduction method. We hypothesized that unfertilized trees would show similar positive growth and physiological responses to elevated [CO2] as the fertilized trees. Growth in elevated [CO2] stimulated (relative) net photosynthesis and (absolute) total biomass accumulation. Relative total biomass increased, and leaf nitrogen remained stable, only during the first year of the experiment. Toward the end of the experiment, signs of photosynthetic acclimation occurred, i.e., down-regulation of the photosynthetic apparatus. Relative growth rate was not significantly affected by elevated [CO2] because although NAR was increased, the effect on relative growth rate was negated by a reduction in leaf area ratio. Neither leaf area nor leaf P concentration was affected by growth in elevated [CO2]. Nodule mass increased on roots of unfertilized trees exposed to elevated [CO2] compared with fertilized trees exposed to ambient [CO2]. There was also a biologically significant, although not statistically significant, stimulation of nitrogenase activity in nodules exposed to elevated [CO2]. Root nodules of trees exposed to elevated [CO2] were smaller and more evenly spaced than root nodules of trees exposed to ambient [CO2]. The lack of an interaction between nutrient and [CO2] effects on growth, biomass and photosynthesis indicates that the unfertilized trees maintained similar CO2-induced growth and photosynthetic enhancements as the fertilized trees. This implies that alder trees growing in natural conditions, which are often limited by soil N availability, should nevertheless benefit from increasing atmospheric [CO2]. 相似文献
16.
We compared hydraulic architecture, photosynthesis and growth in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), a shade-intolerant species, and western hemlock (Tsuga heterophylla (Raf.) Sarg.), a shade-tolerant species, to study the temporal pattern of release from suppressive shade. In particular, we sought to determine whether hydraulic architecture or photosynthetic capacity is most important in constraining release. The study was conducted at two sites with mixed stands of 10- to 20-year-old Douglas-fir and western hemlock. At one site, the stand had been thinned allowing release of the understory trees, whereas at the other site, the stand remained unthinned. Douglas-fir had lower height growth (from 1998-2003) and lower relative height growth (height growth from 1998 to 2003/height in 1998) than western hemlock. However, relative height growth of released versus suppressed trees was higher in Douglas-fir (130%) than in western hemlock (65%), indicating that, although absolute height growth was less, Douglas-fir did release from suppression. Release seemed to be constrained initially by a limited photosynthetic capacity in both species. Five years after release, Douglas-fir trees had 14 times the leaf area and 1.5 times the leaf nitrogen concentration (N (area)) of suppressed trees. Needles of released western hemlock trees had about twice the maximum assimilation rate (A (max)) at ambient [CO(2)] as needles of suppressed trees and exhibited no photoinhibition at the highest irradiances. After release, trees increased in leaf area, leaf N concentration and overall photosynthetic capacity. Subsequently, hydraulic architecture appeared to constrain release in Douglas-fir and, to a lesser extent, in western hemlock. Released trees had significantly less negative foliar delta(13)C values than suppressed trees and showed a positive relationship between leaf area:sapwood area ratio (A (L)/A (S)) and delta(13)C, suggesting that trees with more leaf area for a given sapwood area experienced a stomatal limitation on carbon gain. Nonetheless, these changes had no significant effects on leaf specific conductivities of suppressed versus released trees of either species, but leaf specific root conductance was significantly lower in released Douglas-fir. 相似文献
17.
Specific chloroplast proteins, gas exchange and dry matter production in oak (Quercus robur L.) seedlings and clonal cherry (Prunus avium L. x pseudocerasus Lind.) plants were measured during 19 months of growth in climate-controlled greenhouses at ambient (350 vpm) or elevated (700 vpm) CO(2). In both species, the elevated CO(2) treatment increased the PPFD saturated-rate of photosynthesis and dry matter production. After two months at elevated CO(2), Prunus plants showed significant increases in leaf (55%) and stem (61%) dry mass but not in root dry mass. However, this initial stimulation was not sustained: treatment differences in net assimilation rate (A) and plant dry mass were less after 10 months of growth than after 2 months of growth, suggesting acclimation of A to elevated CO(2) in Prunus. In contrast, after 10 months of growth at elevated CO(2), leaf dry mass of Quercus increased (130%) along with shoot (356%) and root (219%) dry mass, and A was also twice that of plants grown and measured at ambient CO(2). The amounts of Rubisco and the thylakoid-bound protein cytochrome f were higher in Quercus plants grown for 19 months in elevated CO(2) than in control plants, whereas in Prunus there was less Rubisco in plants grown for 19 months in elevated CO(2) than in control plants. Exposure to elevated CO(2) for 10 months resulted in increased mean leaf area in both species and increased abaxial stomatal density in Quercus. There was no change in leaf epidermal cell size in either species in response to the elevated CO(2) treatment. The lack of acclimation of photosynthesis in oak grown at elevated CO(2) is discussed in relation to the production and allocation of dry matter. We propose that differences in carbohydrate utilization underlie the differing long-term CO(2) responses of the two species. 相似文献
18.
If an increase in temperature will limit the growth of a species, it will be in the warmest portion of the species distribution. Therefore, in this study we examined the effects of elevated temperature on net carbon assimilation and biomass production of northern red oak (Quercus rubra L.) seedlings grown near the southern limit of the species distribution. Seedlings were grown in chambers in elevated CO(2) (700 μmol mol(-1)) at three temperature conditions, ambient (tracking diurnal and seasonal variation in outdoor temperature), ambient +3 °C and ambient +6 °C, which produced mean growing season temperatures of 23, 26 and 29 °C, respectively. A group of seedlings was also grown in ambient [CO(2)] and ambient temperature as a check of the growth response to elevated [CO(2)]. Net photosynthesis and leaf respiration, photosynthetic capacity (V(cmax), J(max) and triose phosphate utilization (TPU)) and chlorophyll fluorescence, as well as seedling height, diameter and biomass, were measured during one growing season. Higher growth temperatures reduced net photosynthesis, increased respiration and reduced height, diameter and biomass production. Maximum net photosynthesis at saturating [CO(2)] and maximum rate of electron transport (J(max)) were lowest throughout the growing season in seedlings grown in the highest temperature regime. These parameters were also lower in June, but not in July or September, in seedlings grown at +3 °C above ambient, compared with those grown in ambient temperature, indicating no impairment of photosynthetic capacity with a moderate increase in air temperature. An unusual and potentially important observation was that foliar respiration did not acclimate to growth temperature, resulting in substantially higher leaf respiration at the higher growth temperatures. Lower net carbon assimilation was correlated with lower growth at higher temperatures. Total biomass at the end of the growing season decreased in direct proportion to the increase in growth temperature, declining by 6% per 1 °C increase in mean growing season temperature. Our observations suggest that increases in air temperature above current ambient conditions will be detrimental to Q. rubra seedlings growing near the southern limit of the species range. 相似文献
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The effects of culture media and light intensity on in vitro growth of Oncidium ‘Aloha Iwanga‘ were investigated under CO2 enrichment condition. Height, fresh and dry weight of the Oncidium seedlings were measured, and the leaf number per plant, shoot number per plant, leaf width and leaf chlorophyll content were also investigated. The results were as follows: 1) The seedling height, fresh and dry weight, leaf number per plant, leaf width and leaf chlorophyll content of the shoots growing on MS complete culture medium were higher than those on 1/2MS, VW and 1/2VW media. The root number per plant and ratio of dry matter of the seedlings cultured on 1/2MS and 1/2VW media were higher than those on MS and VW; 2) The seedling height, flesh weight, dry weight, dry matter ratio and leaf chlorophyll content, leaf length, leaf width, root length, leaf number per plant, root number per plant of seedlings of Oncidium growing under 4 500 lx and 1 700 lx were higher than those under 750 lx. However, there was no significant difference in those growth parameters mentioned above while dealing with 4 500 lx and 1 700 lx except for the seedling height. Nevertheless, the leaf color of plants under 4 500 lx was lighter and the leaves of the lower parts became yellowish in comparison with those growing under 1 700 lx. 相似文献
20.
Effects of temperature on growth and wood anatomy were studied in young European beech (Fagus sylvatica L.) grown in 7-l pots for 2.5 years in field-phytotron chambers supplied with an ambient (approximately 400 micromol mol-1) or elevated (approximately 700 micromol mol-1) carbon dioxide concentration ([CO2]). Temperatures in the chambers ranged in increments of 2 degrees C from -4 degrees C to +4 degrees C relative to the long-term mean monthly (day and night) air temperature in Berlin-Dahlem. Soil was not fertilized and soil water and air humidity were kept constant. Data were evaluated by regression analysis. At final harvest, stem diameter was significantly greater at increased temperature (Delta1 degrees C: 2.4%), stems were taller (Delta1 degrees C: 8.5%) and stem mass tree-1 (Delta1 degrees C: 10.9%) and leaf area tree-1(Delta1 degrees C: 6.5%) were greater. Allocation pattern was slightly influenced by temperature: leaf mass ratio and leaf area ratio decreased with increasing temperature (Delta1 degrees C: 2.3% and 2.2% respectively), whereas stem mass/total mass increased (Delta1 degrees C: 2.1%). Elevated [CO2] enhanced height growth by 8.8% and decreased coarse root mass/total mass by 10.3% and root/shoot ratio by 11.7%. Additional carbon was mainly invested in aboveground growth. At final harvest a synergistic interaction between elevated [CO2] and temperature yielded trees that were 3.2% taller at -4 degrees C and 12.7% taller at +4 degrees C than trees in ambient [CO2]. After 2.5 seasons, cross-sectional area of the oldest stem part was approximately 32% greater in the +4 degrees C treatment than in the -4 degrees C treatment, and in the last year approximately 67% more leaf area/unit tree ring area was produced in the highest temperature regime compared with the lowest. Elevated [CO2] decreased mean vessel area of the 120 largest vessels per mm2 by 5.8%, causing a decrease in water conducting capacity. There was a positive interaction between temperature and elevated [CO2] for relative vessel area, which was approximately 38% higher at +4 degrees C than at -4 degrees C in elevated [CO2] compared with ambient [CO2]. Overall, temperature had a greater effect on growth than [CO2], but elevated [CO2] caused quantitative changes in wood anatomy. 相似文献