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1.
城市绿化红皮云杉树冠形状研究 总被引：1，自引：0，他引：1
红皮云杉是东北地区重要的造林和城市绿化的优秀树种,在城市环境的红皮云杉树形优美,树冠浓密圆润。本文对吉林省7个城市绿化的红皮云杉进行了调查研究,结果表明,红皮云杉的冠高比接近黄金数0.618 0,而森林中的红皮云杉冠高比0.402 2。 相似文献
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枫香人工林林内外降水重金属含量变化 总被引：4，自引：1，他引：3
为揭示长沙市郊天际岭枫香人工林林内外降水中重金属含量的迁移规律,对该区域森林生态系统降水再分配过程中重金属含量变化进行了研究.结果表明:(1)枫香人工林林外降水、穿透水和树干茎流中各种重金属含量明显不同.林外降水中Zn含量最高(2.532mg/L),Cu含量最低(0.044mg/L);穿透水和树干茎流中Mn含量最高.分别为0.572mg/L、0.563mg/L,Cu含量最低,分别为0.047 mg/L、0.049 mg/L.(2)Fe和Zn在穿透水和树干茎流中的含量低于林外降水,出现明显的负淋溶现象.(3)在林外降水中检测到的Cd在穿透水和树干茎流中未检测到.表明枫香林冠对Cd具有较强的吸附能力.(4)随着降水量的增大,林外降水、穿透水和树干茎流中的重金属含量均明显减小. 相似文献
3.
Shiro Tsuyuzaki Akira Haraguchi 《林业研究》2009,20(2)
日本北海道东部有两块发展成熟的湿地森林,分别是具有氮固定作用的日本桤木（Alnusjaponica Steud）组成的阔叶林和库页云杉（Piceaglehnii Masters）构成的针叶林,而且两块林地间具有突变的边界。为了阐明突变边界的维持机制,本文研究了森林剖面、水位、地下水、降雨化学、与微环境有关的幼苗建成格局及种子迁移。研究表明,地下水位剖面并不能充分地解释突转临界的形成,但是,两种林地的地下水化学成分存在显著差异,具体表现为库页云杉林地下水中EC,Na^＋,心,Mg^2＋,Ca^2＋和Cl^-含量明显要高于日本桤木林的,而地下水pH值又较低。库页云杉林降雨中富含Na^＋,Ca^2＋和Cl^-,表明降雨是导致两种林分土壤表层水化学成分差异的主要原因。六月末,库页云杉林的太阳辐射少于2．2MJ·m^-2．d^-1;而日本桤木林太阳辐射强度为1．0—3．7MJ·m^-2.d^-1。土壤表层苔藓主要是泥炭藓,在库页云杉林内覆盖率为60％,而日本桤木林的仅为10％：这一差异与土壤表层水pH值有关。有70％株高在1．3米以下的库页云杉苗木建立在苔藓层上。播种造林实验表明,在库页云杉林2个树种的种子萌发率和幼苗存活率都较高。因此,库页云杉在日本桤木林内繁殖能力较弱,主要是缺少适宜的微环境和较低的苗木建成能力。日本桤木仅靠再萌发繁殖,在两种林分内幼苗较少;此外,日本桤木种子向库页云杉林内的迁移也受到较大的限制,加之库页云杉林内太阳辐射强度较低,导致日本桤木幼苗存活率较低。基于以上结果,我们认为日本桤木与库页云杉形成了各自特有的生长环境,而对彼此的生长环境不适应,抑制了自身种苗向对方林分的扩张和自然再造过程。图9表1参32。 相似文献
4.
长沙市郊枫香人工林降水再分配及养分动态 总被引：5，自引：3，他引：2
采用定位试验研究方法对长沙市郊枫香人工林生态系统水文过程及养分动态进行了研究.结果表明：该森林生态系统春季平均降雨量为18.73 mm,其中以林冠穿透雨形式输入林地水量占降雨量的81.63%,以树干流形式输入林地水量占1.54%;树冠截留率随降雨量的增大而减小,平均树冠截留率为16.83%;在枫香人工林中,降水pH值的变化不大,且基本呈中性;养分元素质量浓度在各过程中变化不尽相同,Ca^2＋、K^＋质量浓度在穿透水和树干茎流中呈上升趋势,NH4^＋质量浓度在树干茎流中呈上升趋势,Zn^2＋、PO4^3-质量浓度呈下降趋势,Mg^2＋、Cu^2＋质量浓度变化不大. 相似文献
5.
沙地红皮云杉森林群落生物量和生产力的初步研究 总被引：7，自引：0，他引：7
红皮云杉(Picea koraiensis Nakai)是亚寒带的针叶树种,也是第三纪古老的稀有种、自然分布区仅限于东亚。我国东北长白山、小兴安岭林区,常见红皮云杉与红松、鱼鳞松、臭冷杉混交生长;大兴安岭北坡呼玛河、阿穆河水系河谷沿岸有少量分布。在内蒙古自治区昭乌达盟克旗白音敖包(蒙语:美丽的山头)沙丘上,却分布有大面积的红皮云杉天然原始林。这片沙地红皮云杉林,在国内、外均属罕见,对于研究我国东北西部、内蒙东部草原地带的森林资源与森林发生发展规律,以及“三北”地区沙地生态条件等方面都有重要价值。为了查明固定沙丘红皮云杉森林群落的结构与森林生产力;探讨红皮云杉异龄、复层结构的常绿针叶林的生物量及其分配情况,我们在1978—1979年做了沙地红皮云杉森林群落综合调查研究,本项研究是其中的一部分。 相似文献
6.
对丹江口库区马尾松林、柏木林和栎类阔叶林3种主要森林类型及单木树干茎流特征进行了研究,结果表明:3种森林类型树干茎流率为0.58%～7.69%,树干茎流量与降水量成线性相关,回归方程达到极显著水平;不同树种间的树干茎流量差异显著,影响树干茎流量的主要因子是冠型结构、胸径、树皮特征和分枝角度。 相似文献
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9.
临江林业局从1966年起即将红皮云杉(Picea Koraiensis)列为主要更新树种之一。二十年来,共营造红皮云杉人工林80,559亩,其中已郁闭成林的有14,179亩,通过实践使我们认识到,该树种材质优良,树干通直高大,树形优美,生长迅速,适应性强,具有良好的天然更新能力。人工育苗造林容易的特点,适合营造用材林和城市绿化,很有发展前途。 相似文献
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11.
There is an abrupt boundary between two well-developed wetland forests, a stand consisting of a broad-leaved, nitrogen-fixer Alnus japonica and a stand of the needle-leaved Picea glehnii Masters, in eastern Hokkaido, Japan. To clarify maintenance mechanisms, we studied the forest profile, water level, groundwater and precipitation chemistry, seedling establishment patterns in relation to microhabitats, and seed migration. The profile of groundwater level insufficiently explained the abrupt boundary formation, while the groundwater chemistry differed significantly between the two forests; i.e., EC, Na+, K+, Mg2+, Ca2+ and Cl- were higher in P. glehnii forest and pH was lower. Precipitation in P. glehnii forest contained richer Na+, Ca2+ and Cl-, indicating that the differences in surface-water chemistry were mostly derived from precipitation. Solar radiation was less than 2.2 MJ·m-2·d-1 on P. glehnii forest in late June, while that was patchily distributed in A. japonica forest with a range from 1.0 to 3.7 MJ·m-2·d-1. Moss cover on the soil surface, most of which were made of Sphagnum spp., was 60% in P. glehnii forest, but was 10% in A. japonica forest. Surface water chemistry represented by pH was considered to determine the development of Sphagnum moss. About 70% of P. glehnii seedlings < 1.3 m in height established on moss cover. Seed-sowing experiments suggested that seed germination and seedling survival for both species were significantly higher in P. glehnii forest. Therefore, the regeneration of P. glehnii in A. japonica forest was negligible, owing to the paucity of favorable microhabitats and low seedling establishment. A. japonica regenerated only by resprouting, and the seedlings were few in both forests. In addition, A. japonica seed migration into the P. glehnii forests was greatly restricted, and low solar radiation in the P. glehnii forest contributed to low seedling survival. Based on those results, we concluded that Picea glehnii and Alnus japonica could develop distinct and selfish environments being unsuitable for the other species and inhibit natural afforestation of another species each other by excluding invasion. 相似文献
12.
《Forest Ecology and Management》1999,122(3):243-248
Acidity and chemistry of open and intercepted precipitation in a Chinese fir plantation in Fujian, China, were monitored at two sites located at varying distances from the SO2 sources. Acidification and chemical enrichment were observed to be extremely significant for stemflow, but only slightly for throughfall. The pH values for rainfall showed some seasonal patterns. In contrast, the electric conductivity and chemical components showed a strong seasonal trend over the three-year period, which were supposed to be negatively correlated with the amount of rainfall. Differences in pH values between two sites suggested the acidifying effects of sulfur dioxide on precipitation. 相似文献
13.
Interception loss, throughfall and stemflow chemistry in pine and oak forests in northeastern Mexico
Interception loss, gross precipitation, throughfall and stemflow solution chemistry beneath pine (Pinus pseudostrobus Lindl.), oak (Quercus sp.) and pine-oak natural forest canopies in northeastern Mexico were measured. Coefficients of variation for throughfall were 12% in pine and oak canopies and 17% in the mixed pine-oak canopy. The variability of stemflow averaged 66, 126 and 73% for pine, oak and the mixed pine-oak canopies, respectively. Linear regression analysis of net versus gross precipitation for the three canopies showed highly significant correlations (r = 0.974-0.984). Total precipitation during the experimental period was 974 mm and estimated interception loss was 19.2, 13.6 and 23% for the pine, oak and pine-oak canopies, respectively. Stemflow did not occur following rainfall events of less than 4 mm and, in all canopies, stemflow represented a minimal proportion of gross precipitation (0.60, 0.50 and 0.03% for pine, oak and pine-oak, respectively). Throughfall pH in pine (6.2), oak (6.3) and pine-oak (6.3) canopies was significantly more acidic than gross precipitation (6.6). Stemflow pH ranged from 3.7 (pine) to 6.0 (oak). The pine-oak canopy registered the highest throughfall and stemflow electrical conductivities, 104 and 188 microS cm(-1), respectively. Net nutrient leaching of K, Mg, Na, Fe, Mn and Zn was significantly higher from the pine-oak canopy than from the pure pine and oak canopies. Mean depositions of Ca and Cu in throughfall behaved similarly among the three types of canopies. A greater proportion of Zn in gross precipitation was absorbed by the oak canopy than by the pine and pine-oak canopies. Enrichment factors beneath the pine-oak canopy relative to gross precipitation varied from 1.2 to 3.2 for macro-nutrients (Ca, K, Mg and Na) and from 1.4 to 3.1 for micro-nutrients (Cu, Fe, Mn and Zn). Stemflow depositions of Ca, K, Mg and Cu were higher in the pine-oak canopy, whereas stemflow depositions of Na, Fe, Mn and Zn were higher in the pine canopy. 相似文献
14.
对黑龙江省东部山地白桦人工林生态系统的大气降水、穿透水、树干茎流和地表径流中的pH值、溶解氧、浊度、总溶解固体、电导率、氧化还原电位、K、Na、Ca、Mg、Cu、Zn、Mn和Fe等水质指标进行了测定.结果表明:大气降水经过白桦人工林生态系统后,浊度和总溶解固体值逐渐升高.穿透水除Ca元素外,其他化学元素含量均有不同程度的增加,化学元素含量排序为:K＞ Ca＞ Na＞ Mg＞ Mn＞ Fe ＞Zn＞ Cu.树干茎流中各化学元素含量排序为:K＞Ca＞Mg ＞Na＞Fe ＞Mn ＞Zn ＞Cu.地表径流中各化学元素含量为:K＞ Ca＞ Na＞ Mg＞ Fe＞ Mn＞ Zn＞ Cu.除Na、Ca元素外,大气降水中其他元素的变异系数均较大.穿透水和树干茎流中Cu元素的变异系数大于其他元素,地表径流中Zn元素的变异系数最大.根据淋溶系数的大小排列,穿透水中各化学元素的淋溶序列是:Mn＞K＞Mg＞Fe＞Cu ＞Zn＞ Na＞ Ca.树干茎流中各化学元素的淋溶序列是:K ＞Mn＞ Mg＞ Fe ＞Cu ＞Zn＞ Ca＞ Na.经过淋洗后,穿透水和树干茎流中K和Mg元素增加较多,Ca元素出现负淋溶. 相似文献
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Hideo Tomizawa Masae Oikawa Fumihiko Nishio Akira Haraguchi 《Journal of Forest Research》1997,2(3):189-192
A survey was made of seasonal changes in pH and electronic conductivity (EC) of precipitation inAlnus japonica (Thunb.) Steud. forest in Kiritapp mire, Hokkaido, Japan. The average pH of throughfall and stem flow was higher than that
of bulk deposition. When the pH of bulk deposition exceeded 5.5, however, pH of throughfall and stem flow was lower than that
of bulk deposition. The EC of stem flow was always higher than throughfall, and that of throughfall higher than that of bulk
deposition. The EC of stem flow was highest during the first defoliation period ofA. japonica. On the other hand, the differences in the EC of throughfall and bulk deposition was very few just after the first defoliation
period ofA. japonica. This implies that the chemical properties of throughfall and stem flow are strongly affected by the phenology of the plants. 相似文献
16.
M.K. Mahendrappa 《Forest Ecology and Management》1990,30(1-4):65-72
The flow of nutrients throughout different components of forests was characterized using 13 years of data from a nutrient-cycling study involving three hardwood (broadleaved) and six softwood (conifer) forest stands. Included in this report is information on the distribution and chemistry of rainwater as it affects the quantity of nutrients cycled as throughfall and stemflow in different stands. A general formula empirically derived for partitioning rainwater into throughfall and stemflow is also described.
The empirically derived equations were found to be suitable for calculating without rain data on an event basis, the weekly or monthly quantity of throughfall and stemflow reaching the ground under different stands. These equations were evaluated to increase their portability and applicability to forest stands of different regions. The results obtained with these calculations validated the among-species differences in the measured values of throughfall and stemflow. The differences among tree species with respect to their abilities to alter rain chemistry were also found to be significant. The differences in the concentrations of hydrogen and sulfate ions and total dissolved solids in the throughfall and stemflow samples as compared to those in the rainwater are also reported. 相似文献
17.
本文用统计分析方法对江西分宜县山下林场杉木、马尾松人工林的林内降雨、林冠截留和树干茎流进行了研究。结果表明:在该林分中林内降雨量和树干茎流量随降雨量的增加而以直线形式增加;林冠截留量随降雨量的增加呈幂函数关系上升。在杉木林内,随郁闭度的增大,林内降雨率和树干茎流率减少,而林冠截留率增大,马尾松林和杉木林相比,林内降雨率和树干茎流率较大,而林冠截留率较小。 相似文献
18.
We investigated the adaptation of three spruce species (Picea glehnii Masters, P. jezoensis Carr. and P. abies Karst.) to growth in northern Japan on serpentine soils (characterized by high concentrations of heavy metals and Mg, a low Ca/Mg ratio and low fertility) and fertile brown forest soils. Among species, seedling survival on serpentine soil was highest in P. glehnii. Shoot growth of P. glehnii was similar whether grown on serpentine or brown forest soil, whereas shoot growth of the other species was significantly less on serpentine soil than on brown forest soil. On serpentine soil, needle life span of P. glehnii was at least 3 years longer than that of the other two species. Needle area per shoot of P. glehnii was significantly higher on serpentine soil than on brown forest soil up to a shoot age of 8 years. In all three species, light-saturated photosynthetic rate (Pmax) decreased with needle age independently of soil type. However, on serpentine soil, Pmax in P. glehnii was higher, particularly in older needles, than in the other species. Furthermore, on serpentine soil, needle concentrations of nitrogen and phosphorus were higher in P. glehnii than in the other species. We conclude that P. glehnii is better adapted to serpentine soil than P. jezoensis and P. abies at least in part because of its greater needle life span and higher needle nutrient concentrations. 相似文献
19.
Sugar maple decline has been observed in northern Pennsylvania since the early 1980s. We investigated the interactions between soil moisture stresses in sugar maple and other factors, such as soil chemistry, insect defoliation, geology, aspect, slope, topography, and atmospheric deposition. In the summer of 1998, we sampled 28 sugar maple (Acer saccharum Marsh.) plots drawn from the USFS Forest Inventory and Analysis (FIA) plots, containing declining and non-declining sugar maple trees across northern Pennsylvania for a variety of soil physical and chemical parameters, site characteristics, and tree health. Foliage from declining plots was found to have significantly lower base cations and higher Mn as compared to that from non-declining plots. Soils in declining plots had lower base cations and pH, a Ca:Al−≤1, lower percent clay and higher percent sand and rock fragments than soils on non-declining plots, suggesting that trees on declining plots are at risk of nutritional and drought stress. Regression relationships between foliar and soil chemistry indicated that foliar nutrition was highly correlated with soil chemistry in the upper 50 cm of the soil. Declining sugar maple plots in this study occurred at higher elevations on sandstone dominated geologies. Soils were found to be base poor-sandy soils that contained high percentages of rock fragments. Soils below 50 cm on declining plots had lower soil pH and foliar chemistry indicated lower foliar base cations. A trend, while not significant was found with declining plots experiencing a greater number of and more severe insect defoliations. 相似文献
20.
Juha Heiskanen 《New Forests》2013,44(1):101-118
Sphagnum peat has been the most commonly used growing medium in containers in tree nurseries worldwide for its good growing properties. As a result of increasing costs and environmental incentives, seedling-growers are seeking more local growing medium components such as composts. Composts are, however, diverse products with varying chemical, physical, and hygienic properties and therefore require thorough testing before real-world use. In this study, a commonly used compost (raw materials: sewage sludge, biowaste, peat, wood chips) was tested for feasibility as a component (0–30 vol.%) of a sphagnum peat container medium for growing Norway spruce (Picea abies (L.) Karst.) container seedlings in a forest-tree nursery. In proportions of up to 30% in peat, the compost additive used was shown to be a feasible material for seedling growing in forest nurseries. On average, the seedlings grew best in pure peat, but the compost additions to peat showed no marked reduction in seedling growth in greenhouses, nor were there any effect on seedling growth in the first summer after outplanting. However, a slightly elevated risk of seed non-germination and of seedling mortality was observed when the growing media contained compost in proportions of 20% or more. The compost additive in peat also changed the bulk density, structure, and chemical properties of the medium during nursery growing. The results suggest that seedling watering and fertilisation should be adjusted for each growing medium mix separately to achieve correct water, oxygen, and nutrient availability in containers during nursery growing. 相似文献