普瑞杨、46杨及107杨的林内SO2浓度及叶片硫酸根离子含量差异

[目的]研究3种杨树对空气中SO₂的吸收和转化作用,探索普瑞杨抗SO₂的机制以及净化大气的能力。[方法]在普瑞杨、46杨和107杨森林中,测定林内、林外空气中SO₂浓度的日动态变化,并测定在SO₂污染环境和非污染环境条件下杨树叶片中硫酸根(SO₄^2-)离子的浓度,依此比较3种杨树对SO₂污染的净化作用。[结果]从林内、林外SO₂浓度的日动态变化可见,3种杨树均能吸收SO₂,其中,普瑞杨吸收SO₂、净化空气的能力显著大于107杨和46杨。无论在高浓度还是低浓度SO₂环境下,普瑞杨叶片中的硫酸根离子含量均显著高于46杨和107杨,说明普瑞杨具有更强的吸收SO₂并转化为无毒含硫化合物的能力,这也是普瑞杨抗SO₂的重要机理。[结论]普瑞杨具有比107杨和46杨更强的净化SO₂污染环境的能力,...     

盐碱胁迫对2种地被竹叶绿素含量的影响

以黄条金刚竹(Sasaella masamuneana f. aureostriata)、铺地竹(Pleioblastus argenteostriatus)为试材,将2种中性盐NaCl、Na₂SO₄和2种碱性盐 NaHCO₃、Na₂CO₃按不同比例混和,模拟出盐碱度各不相同的盐碱条件,研究不同盐碱胁迫处理对2种地被竹叶绿素含量的影响,旨在为今后优良耐盐地被竹选择及有效应用提供参考。结果表明,低浓度中性盐胁迫下,黄条金刚竹叶绿素a含量呈现“升高—降低—升高”的趋势,其余处理叶绿素a含量变化较为平缓,说明植株始终受到抑制;铺地竹受到胁迫后,叶绿素a在胁迫初期均呈现上升趋势,但随着胁迫时间的推移,叶绿素a含量呈现明显的下降趋势,尤其以盐浓度300 mmol/L处理最为明显。2种竹叶绿素b含量变化基本呈现初期上升后期下降的趋势。碱性盐胁迫下,2种竹的叶绿素a和b含量变化规律不明显,但是含量总体呈现下降的趋势。     

大夫山森林公园大气环境中污染物浓度变化及评价

利用长期定位观测方法对大夫山森林公园的大气质量进行监测,分析了大夫山森林公园大气污染源的种类、数量、分布规律,包括NO、NO₂、NO_x和SO₂浓度的日变化规律、季节变化规律进行了探讨。在此基础上,通过分析森林公园大气污染物超标率和分担率情况来评价大夫山森林公园大气质量的影响。结果表明,大夫山森林公园的大气质量非常良好,SO₂和NO_x秋冬季对大气环境有轻微污染,污染分担率最大的SO₂,其次是NO_x,而NO和NO₂对大夫山森林公园环境不产生影响。为进一步提高森林公园的大气环境质量,建议增加冬季常绿阔叶树种。       

大气臭氧污染植物指示研究进展

近年来,大气臭氧（O₃）污染问题得到社会各界的广泛关注。开展大气O₃污染的指示监测工作对于保护人体健康、农作物以及森林植被具有重要的现实意义。利用敏感植物指示大气O₃污染状况以其简便易行的技术优势,已在欧美等发达国家得到广泛应用。文中介绍O₃胁迫对植物的伤害机理,不同植物对O₃胁迫敏感性差异的成因以及利用植物指示监测大气O₃污染的评价方法。为进一步提高利用植物指示大气O₃污染技术的应用价值,提出应强化以下3个方面的研究:1）深入研究敏感植物对O₃胁迫的生理响应机制,开发时效性强的指示评价指标;2）针对不同的气候条件筛选识别对大气O₃污染敏感的乡土植物,并归纳总结各敏感植物的适用条件;3）推进大气O₃污染植物指示评价方法的标准化,提高监测结果的可靠性和可比性。     

西安城区植被净化大气污染物的时间变化

基于植被净化大气的机理,分析了净化量与污染物浓度、叶面指数等的关系,系统收集1991~2000年西安市TSP、SO₂、NO_X月均浓度,结合实验观察,得出:①西安市针叶林、阔叶林TSP、SO₂、NO_X净化量计算的经验公式。② TSP、SO₂、NO_X浓度在年内变化呈U字型,叶面指数年内变化呈倒U字型,二者变化不同步,植被对污染物净化量的年内变化整体也呈倒U字型。③ 1991~2000年TSP、SO₂、NO_X浓度的年际变化整体都是下降的,其中都有波动;10年来的植被覆盖率基本不变;植被对TSP、SO₂、NO_X的净化量与其浓度的年际变化同步,即成正比关系。       

2020年春节期间烟花禁放对安庆市空气质量效果评估

利用2019和2020年空气质量数据,进行了春节期间烟花禁放对安庆市空气质量的效果评估。结果表明:安庆市2020年烟花禁放后,春节期间优良天气比例为87.5%,比2019年提高25%,没有出现中度污染以上等级的天气。2020年除夕及正月初一,安庆市PM₁₀及PM_2.5的峰值浓度比2019年同期分别降低了78.8%、70.5%,SO₂及NO₂略有下降。2020年春节期间,烟花燃放对PM₁₀及PM_2.5的平均贡献量比2019年分别下降了81.7%、76.4%,说明烟花禁放起到了显著的污染削峰作用。此外,2020年春节期间城区及市郊PM₁₀及PM_2.5浓度比禁燃前都有所下降,且城区的峰值浓度比市郊下降得更为显著,禁放后PM₁₀及PM_2.5质量浓度的空间差异性进一步缩小。     

成都西部地区污染物浓度与气象条件相关性分析

利用成都西部地区彭州、都江堰、崇州、郫都、温江、邛崃、蒲江2018年逐小时环境数据主要为NO、NO₂、SO₂、CO、O₃、PM_2.5、PM₁₀浓度资料以及同期、同地气象观测资料包括气温、降雨量、两分钟平均风速和风向及温江探空站资料,分析了成都市西部地区大气污染物浓度变化的特征和规律,进一步探索了成都西部各类污染物的气象影响条件,得出了成都西部地区污染气象特征:①成都西部地区春、夏季O₃浓度高,颗粒物和SO₂浓度低,秋冬季则相反;成都西部地区各个区县PM_2.5/PM₁₀比例都高于50%。②2018年温江O₃超标日数最多,高达75 d,崇州PM₁₀超标日数最多,达54 d,温江和崇州PM_2.5超标日数一样,为105 d;都江堰空气质量最优,各种污染物超标日数在7个区市县中最低。成都市西部地区PM_2.5和PM₁₀日变化呈明显的“W”型,一天内O₃循环包含四个阶段,各阶段浓度变化呈单峰型态势。③SO₂质量浓度整体上与湿度(除蒲江和邛崃外)呈负相关;O₃浓度变化与温度及相对湿度分别为明显正相关和负相关,NO₂、CO、PM_2.5和PM₁₀质量浓度与温度均呈明显负相关。各污染物在非降水日浓度值明显高于降水日,说明降水对颗粒物的清除作用十分明显,崇州、彭州、郫都、蒲江降水清除颗粒物量级高于40μg/m³。     

苏北城市秋冬季节大气细颗粒物污染来源解析研究

利用宿迁学院国控站点监测数据、气象数据和在线源解析数据,分析了宿迁市秋冬季节大气细颗粒物污染特征。结果表明:机动车排放是宿迁学院站点周边PM_2.5最主要的来源,贡献率为36.67%;其次为燃煤和工业污染,贡献率分别为20.53%和15.45%;扬尘和二次无机盐也分别贡献了10.29%和11.91%。提出了在秋冬季重污染应急响应期间要加强机动车排放管控和二次无机组分前体物SO₂、NO_x及NH₃排放源的管控,以减少本地排放影响。     

肥料配置对国槐幼苗生长的影响

为探明不同肥料配置对国槐幼苗生长的影响,以不施肥料为对照,设置了6种不同氮磷钾配比,以研究国槐幼苗苗高、地径、冠幅、叶绿素含量和光合参数。结果表明:不同配料配置处理下国槐的苗高、地径和冠幅均显著高于对照,施肥处理的叶绿素a、b含量,净光合速率、气孔导度、胞间二氧化碳浓度和蒸腾速率均显著高于对照,氮磷钾比例为2∶2∶1时国槐的生长状况最好。当氮磷钾比例为2∶2∶1时,即施氮(N)150 kg/hm²、磷肥(P₂O₅)150 kg/hm²、钾肥(K₂O)150 kg/hm²,国槐幼苗苗高、地径、冠幅最大,生长较好,叶绿素含量和光合参数最高,是较好的肥料配置模式。     

干旱胁迫下4种楸树嫁接苗叶绿素含量的变化

为了提高楸树嫁接苗的抗旱性,用盆栽自然干旱法对4种砧木嫁接的豫楸1号幼苗(砧1为金丝楸,砧2为灰楸,砧3为豫楸1号,砧4为梓树)进行干旱胁迫试验。在试验过程中,系统测定了叶绿素a、叶绿素b、叶绿素(a b)含量及叶绿素(a/b)比值的变化。结果表明:4种砧木嫁接的豫楸1号幼苗随干旱胁迫的加剧叶绿素a含量均出现逐渐降低的趋势,含量从高到低依次为砧1嫁接苗、砧3嫁接苗、砧4嫁接苗、砧2嫁接苗,其中砧1与砧2嫁接苗间叶绿素a含量差异显著;叶绿素b含量在干旱胁迫期间总的变化趋势为先增加后降低,但变化幅度均不大;叶绿素(a b)含量变化趋势与叶绿素a含量变化趋势相同,其中砧1与砧2嫁接苗叶绿素(a b)含量差异显著;叶绿素(a/b)比值的变化趋势与叶绿素b含量变化相反。以叶绿素a、叶绿素(a b)含量的变化趋势及叶绿素(a/b)比值为依据来确定不同砧木嫁接的豫楸1号幼苗抗旱能力从强到弱依次为砧1嫁接苗、砧3嫁接苗、砧4嫁接苗、砧2嫁接苗。     

辐射松、马尾松、长叶松与晚松人工林的生长规律比较研究

对九峰试验林场的辐射松、马尾松、长叶松及晚松人工林生长规律的研究结果表明 :长叶松生长最慢 ,而不宜大面积发展 ;辐射松、马尾松与晚松均表现较好 ,且辐射松与晚松材积生长速率高于马尾松 ,至 2 2a后 ,辐射松材积的生长速率将超过晚松 ;辐射松 4a时胸径连年生长量最大 ( 1 85cm) ,树高速生期为 1 2～ 1 6a,材积速生期为 1 4～ 1 7a,数量成熟龄在 40a之后 ;马尾松 4a时胸径连年生长量达最大 ( 1 30cm) ,1 3a树高连年生长量达最大 ( 3 5 0m) ,材积连年生长量 2 8a最高 ( 0 0 1 60 1m3) ,数量成熟龄为 35～ 40a ;晚松胸径连年生长量在第 3年达最大 ( 1 85cm) ,平均生长量 9a时达最大 ( 1 0 8cm) ,树高速生期为 3～ 8a ,材积速生期为4～ 1 5a ,数量成熟龄为 2 5a。     

高温胁迫对黑皮油松主要生理指标的影响

研究高温胁迫对黑皮油松主要生理指标的影响,以不经过处理的叶片为对照组,以不同温度分别处理不同时间的为实验组,测其生理指标。结果显示黑皮油松叶片中的叶绿素a、叶绿素b、叶绿素和类胡萝卜素的含量在高温胁迫40 min后都呈下降的趋势。超氧化物歧化酶（SOD）、过氧化氢酶（CAT）的活性随着高温胁迫时间的延长都呈现出先增加后减小的趋势。高温胁迫确实对黑皮油松的生理指标即色素的含量,超氧化物歧化酶（SOD）、过氧化氢酶（CAT）的活性产生了影响。     

浙江省松材线虫病的发生与防治

通过人工接种松材线虫试验测定“北带”和“南带”２个种源的马尾松和湿地松、火炬松、晓松、刚松４种国外松的结果表明，不同苗龄期的５种松苗均能感染松材线虫，其中马尾松、湿地松具有较强的感病性，在舟山病区林间对自感病寄主的监测调查结果表明，除公认的日本黑松高度发病外，马尾松、湿地松也有一定面积数量株发病，其感病性与苗期人工接种试验结果相似，同时还发现北美二针松和长叶松２种国外松自然发病。由此分析了浙江省松村线虫病发生流行趋势和应采取的防治对策．     

不同苗龄南方红豆杉幼苗的光合特性比较

用 LI-COR 6400便携式光合作用测定仪系统研究南方红豆杉的光合特性,结果表明:①1-4年生南方红豆杉幼苗的光饱和点为1000～1999μmol /m2.s,光补偿点为87-44.81μmol /m2·S,最大净光合速率为1.32～3.00μmol/m2.sl,接近耐阴喜光性植物的光合特征.②不同苗龄南方红豆杉幼...     

Effects of the interaction between drought and shade on water relations, gas exchange and morphological traits in cork oak (Quercus suber L.) seedlings

The combined effect of drought and light on different physiological and biochemical traits was assessed in cork oak (Quercus suber L.) seedlings grown under two levels of light availability and submitted to a long-standing drought. Watering was withdrawn after germination and seedlings were allowed to dry to a water content of ca. 50% of field capacity. At this point, water-stressed seedlings were grown under moderate drought and two light regimes: high light (HL—50%) and low light (LL—2%). Soil water in control plants was kept close to field capacity (90–100%) for both light environments. Water-relations parameters derived from P–V curves, gas exchange and water status at predawn (Ψ_pd) were evaluated at twice during the experiment. Nitrogen and chlorophyll contents were determined in the same leaves used for the gas exchange measurements. In addition, maximum rate of carboxylation (V_cmax) and electronic transport (J_max) were derived from A–C_i curves in well-watered seedlings.

The variation on moisture availability during the experiment was the same under both light environments. In control plants, Ψ_pd was over −0.3 MPa at the two harvests, while stressed seedlings decreased to −0.9 MPa, with no differences between light treatments. Water stress decreased osmotic potentials at full (Ψπ₁₀₀) and zero turgor (Ψπ₀). The regressions between both potentials and Ψ_pd showed a higher intercept in shade grown seedlings. This fact will point out the higher osmoregulation capacity in sun seedlings whatever water availability.

Nitrogen investment on a per leaf mass (N_mass), chlorophyll content (Chl_mass) and SLA tended to show a typical pattern of sun-shade acclimation. Thus, the three parameters increased with shade. Only for N_mass there was a significant effect of watering, since water stress increased N_mass.

LL plants showed a lower photosynthetic capacity in terms of maximum net photosynthesis at saturating light (A_max), which was related to a decrease in V_cmax and J_max. Both parameters varied with specific leaf area (SLA) in a similar way. The low-light environment brought about a higher nitrogen investment in chlorophyll, while under high-light environment the investment was higher in carboxylation (V_cmax) and electronic transport (F_max).

Stomatal conductance to water vapour (g_wv) and A_max were lower in low-light seedlings independently of watering. In addition, there was a trend to keep higher intrinsic water use efficiency (IWUE) under high light environment. The increase of IWUE under water stress was higher in HL seedlings. This was as consequence of the steeper decline in g_wv as Ψ_pd decreased. The decrease of A_max with Ψ_pd occurred in a similar way in LL and HL seedlings. Thus, the HL seedlings tended to sustain a higher ability to increase IWUE than LL seedlings when they were submitted to the same water stress.     

钻天松无菌系建立的初步研究

摘　要:以钻天松侧枝顶芽作为繁殖材料,通过不同消毒剂处理试验,不同生长激素对外殖体愈伤组织形成的诱导,初步建立无菌系。结果表明:0.1%HgCl2 消毒时间最好为9 min;时间短,污染率高;时间过长会导致芽中毒而成活率下降。诱导钻天松愈伤组织形成的最佳培养基配方是1/2MS+ 6BA0. 2mg·L-1 + NAA0. 5mg·L-1 +IBA0.2mg·L-1,低浓度的6BA有利于愈伤组织的形成。     

Chlorophyll and carotenoid concentrations in two varieties of Pinus ponderosa seedlings subjected to long-term elevated carbon dioxide

Two varieties of ponderosa pine (Pinus ponderosa Dougl. var. scopulorum (Rocky Mountain variety) and P. ponderosa var. ponderosa (Sierran variety)) seedlings were subjected to elevated atmospheric CO(2) for two and a half years. The CO(2) concentrations were ambient, ambient + 75 microl l(-1), ambient + 150 microl l(-1) and ambient + 300 microl l(-1), or approximately 350, 425, 500 and 650 microl l(-1) CO(2). After one and a half years of exposure to elevated CO(2) and until the end of the study, seedlings of both varieties showed symptoms of stress including mottling, mid-needle abscission and early senescence. In both varieties, exposure to CO(2) concentrations greater than ambient + 75 microl l(-1) resulted in lower chlorophyll a, chlorophyll b and carotenoid concentrations. At elevated CO(2) concentrations, the concentrations of pigments in needles of the Sierran variety were lower than those in the Rocky Mountain variety. Also, at elevated CO(2) concentrations, the pigment concentrations in the 1-year-old needles of both P. ponderosa varieties were lower than those in current-season needles.     

Comparative study on drought resistance ofLarix olgensis Henry andPinus sylvestris var.mongolica (I)

Water potential (ϕ w) and net photosynthetic rate (Pn) ofLarix olgensis andPinus. sylvestris var.mongolica decreased with the decrease of soil water content. ϕ w and Pn ofL. olgensis changed hardly during the first 9 days after stopping watering, then decreased sharply at the 10th day Pn ofP. sylvestris varmongolica decreased slightly during the first 8 days, then decreased sharply at the 9th day. Their respiration rate, chlorophyll content and their a/b ratio changed hardly. The following 3 conclusions were obtained and discussed exhaustively. (1) ϕ w can be used to direct watering as a sensitive index of judging whetherL. olgensis andP. sylvestris var.mongolica lacking water. (2) The decrease of Pn ofL. olgensis andP. sylvestris var.mongolica when drought had nothing to do with chlorophyll. (3)P. sylvestris var.mongolica had morphological drought resistance, while Lolgensis had physiological drought resistance, and their drought resistance was discussed comparatively first time.