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1.
不同毛竹林土壤水分物理性质的特征比较 总被引：13，自引：0，他引：13
采用对比分析方法,对位于浙江省富阳尖山的集约经营毛竹纯林（含垦复）、天然起源的毛竹木荷混交林,在2004年春季采集不同林分下0～10,20～30,40～50 cm^3个层次的土壤容重圈样品,测定土壤水分-物理性质（水分常数）.结果表明,3类林分土壤总孔隙度是42.98V%～66.45V%,其中非毛管孔隙占总孔隙1/6～1/2,通透性良好.毛管孔隙/非毛管孔隙之比值为未垦复毛竹纯林（3.07）＞垦复毛竹纯林（2.20）＞毛竹木荷混交林（1.66）,因而,毛竹木荷混交林土壤通气状况好于垦复毛竹纯林,未垦复毛竹纯林通气状况相对较差.若以0～50 cm层次着眼：毛竹纯林田间持水量8.43～30.02 mm,毛竹木荷混交林为3.76～48.94 mm;毛竹纯林最佳含水率下限为12.45～88.01 mm,毛竹木荷混交林为46.05～115.20 mm.毛竹木荷混交林的水源涵养潜力和改良土壤结构作用优于毛竹纯林,垦复之后的毛竹林土壤通透性显著提高,但蓄水量又小于相似立地条件下的毛竹纯林或竹木混交林. 相似文献
2.
建瓯市毛竹林土壤养分状况及丰缺分级 总被引：2，自引：0，他引：2
采集了福建省建瓯全市15个乡镇毛竹(Phyllostachys heterocycla cv.pubescens)林表层土壤,对其养分含量进行了测试分析,在此基础上对毛竹林土壤养分含量进行了丰缺分级.结果表明:建瓯市毛竹林土壤较为肥沃,土壤酸碱性适宜毛竹生产;表层土壤有机质含量为较高,为3.98％;全氮平均含量为1.48 g/kg,碱解氮平均含量为167 mg/kg,土壤供氮较为充足;有效磷含量为9.93 mg/kg,远低于毛竹生长所需;速效钾含量为55.4 mg/kg,稍低于毛竹正常生长所需;土壤中量元素钙、镁含量普遍较低.整个建瓯市毛竹林土壤养分存在富氮低磷缺钾的现象,同时缺乏供应中量元素养分的能力,不同乡镇间毛竹林土壤养分失调的种类及程度有较大的变化. 相似文献
3.
生态型毛竹林土壤肥力维持技术初探 总被引：2，自引：0，他引：2
生态型毛竹林是指以发挥水源涵养、水土保持、维持生物多样性、缓解和改善气候变化为主要目标的毛竹林类型,具有较高的生态效益和社会功能.文章在分析垦复毛竹林、未垦复毛竹林、毛竹木荷混交林3种不同经营类型毛竹林土壤理化性质的基础上,根据生态型毛竹林养分功能动态平衡的要求,提出了保持适当比例的针、阔叶树木,改善和优化毛竹林生态结构;采用择伐方式或半封山形式,合理保持立竹度和林龄、径级结构比例;采用带垦方式;开展模式施肥;改造毛竹林为混交林等生态型毛竹林经营技术. 相似文献
4.
建瓯市毛竹林土壤速效氮磷钾含量及空间分布 总被引：2，自引：1，他引：1
采集建瓯市毛竹林表层(0～20 cm)土壤,分析其氮磷钾速效养分含量及空间分布。结果表明:建瓯市毛竹林表层土壤碱解氮平均含量为166.7 mg.kg-1,高于农田土壤碱解氮含量;速效磷含量为9.93 mg.kg-1,低于毛竹生长所需;速效钾含量为55.4 mg.kg-1,低于毛竹生长所需。地统计学分析结果表明,速效钾、速效磷、碱解氮具有中等空间相关性,氮含量的变异性主要由随机性因素引起。建瓯市毛竹林土壤速效养分存在富氮低磷缺钾的现象,在生产实践中应重视磷肥和钾肥的施用。 相似文献
5.
不同人工经营毛竹林土壤理化性质变化 总被引：1，自引：0，他引：1
选择3种人工经营毛竹林:集约经营毛竹纯林,杉-竹混交林和粗放经营毛竹纯林,对其土壤理化性质进行研究,探讨人工经营对毛竹林土壤质量的影响.结果表明:土壤理化性质在3种类型林地中呈现出显著的差异性.土壤容重表现为集约经营竹林＞杉-竹混交林＞粗放经营竹林,孔隙度及毛管孔隙度及土壤持水能力表现为粗放经营纯林＞杉-竹混交林＞集约经营竹林:说明粗放经营的毛竹纯林及混交林土壤具有较好的水文生态功能.粗放经营的毛竹纯林土壤有机质含量显著高于混交林和集约经营竹林,集约经营竹林土壤全氮含量最低,水解氮、速效磷等养分则为混交林最高,说明集约经营竹林由于产出的增加,导致土壤肥力耗损,应加强平衡施肥等生态经营技术在毛竹林经营实践上的应用. 相似文献
6.
近年来,受国内外经济形势的影响,浙江安吉县的毛竹价格逐年下降,毛竹林的经济效益受到影响,如何提高毛竹林的生产力、培育大径竹材已经成为毛竹林经营的重要内容。毛竹林的生产力与土壤养分密切相关,测定分析了安吉县主要毛竹产区笋材两用林的土壤养分,探讨了竹林经营模式、竹林产出与土壤养分状况的关系。结果表明:安吉县毛竹林土壤普遍缺乏速效钾,而土壤有机质含量较为丰富;竹林平均胸径随土壤速效磷含量的增加而增加。因此,培养大径级竹林应增施磷肥和钾肥。研究结果可为优化毛竹林经营模式、提高竹林产量以及合理制定竹林施肥策略提供依据。 相似文献
7.
《经济林研究》2014,(1)
为了研究安徽泾县蔡村不同经营措施对毛竹林的生物量及碳储量的影响情况,对该地区不同经营措施下毛竹林的林分结构及林地土壤养分状况进行了调查,并结合现存生物量进行了分析。结果表明:采用粗放经营、垦复-施农家肥、垦复-施配比肥这3种不同措施经营的毛竹林其平均胸径分别为9.55、11.38和10.89 cm;其平均立竹度分别为0.28、0.36和0.34;调查区内毛竹林地土壤中全氮、全磷、速效磷、可溶性有机碳、铵态氮、硝态氮的含量均随着土层深度的加深而降低;土壤中的钾含量在深度为0~10 cm的土层中最低。各经营措施下毛竹林各器官中的生物量及碳储量分配的大小顺序均为:竹秆竹根竹枝竹叶。粗放经营、垦复-施农家肥、垦复-施配比肥的毛竹林其总生物量分别为76.69、90.03和84.86 t·hm-2,其总碳储量分别为154.96、235.83和229.18 t·hm-2。根据竹龄和采伐习惯估算,采取经营措施的毛竹林平均每年同化CO2的量(26.11 t·hm-2a-1)是粗放经营毛竹林(22.81 t·hm-2a-1)的1.14倍。文中因此认为,从竹林的长期经营效益和生态效益来看,应采取适度或适当的管理与施肥措施(尤以农家肥为佳),这样才可在提高毛竹林生产力的同时增强毛竹林的固碳能力。 相似文献
8.
通过对不同密度的毛竹林林下土壤调查,测定不同密度毛竹林土壤含水率、容重、总孔隙度等物理性状和pH值、有机质、速效氮、速效钾、速效磷等化学性状,研究了不同密度毛竹林土壤质量。当林分密度在2 400株·hm-2时,土壤可以为毛竹林保障水分、养分条件,促进稳产高产,有利于今后的可持续经营。 相似文献
9.
以毛竹鞭根根际和非根际土壤为研究对象,研究不同生长期竹鞭根际与非根际土壤养分含量。结果表明:毛竹鞭根根际土壤p H值、水解氮、速效钾、有效磷含量明显高于非根际土壤,其中p H值平均提高0.82、水解氮含量平均提高111.63 mg/kg、有效磷含量平均提高0.57 mg/kg、速效钾含量平均提高92.33 mg/kg;毛竹鞭根根际与非根际土壤有效锌、有效铜、有效硼含量差异不显著。毛竹鞭根根际土壤水解氮和速效钾含量在不同生长期存在显著差异,表现为在行鞭期较高,在孕笋期和出笋期偏低。 相似文献
10.
建瓯市毛竹林土壤有机质及氮磷钾含量的空间分布 总被引：1，自引：0，他引：1
毛竹产业是建瓯市农村经济的支柱产业,提高毛竹林产量和效益是实现农民增收的重要途径,了解毛竹林土壤的基本肥力性质则是开展毛竹合理施肥,提高毛竹林生产力的基础.研究采集了全市不同乡镇毛竹林土壤表层0～20 cm样品,分析土壤有机质与全量氮磷钾的含量,结果表明:建瓯市各乡镇毛竹林表层土壤有机质含量平均为3.98%,高于当地农田土壤;全氮含量平均为1.48 g·kg-1,与农田土壤大致相当;土壤C/N要显著高于农田土壤;毛竹林土壤中全磷含量平均为2.48 g·kg-1,全钾含量平均为19.09 g·kg-1,相对较高.建瓯毛竹林土壤有机及氮磷钾含量在不同乡镇中分布极为不均,由地统计学插值图件可见,有机质含量在北部及西南部分较高,全氮在四周乡镇较高,全磷在西部较高,全钾在北部及西南部较高. 相似文献
11.
《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
13.
《Scandinavian Journal of Forest Research》2012,27(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献
16.
《Scandinavian Journal of Forest Research》2012,27(2):131-138
The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. 相似文献
17.
18.
《Scandinavian Journal of Forest Research》2012,27(5):472-479
Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken. 相似文献
19.
Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic
or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts
(stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea
(Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content
as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest
N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized
to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea,
largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for
N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant
components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N
released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures
were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality
components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in
the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols.
Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest
age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its
components are mixed. 相似文献
20.
A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste
disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization,
(2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two
pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea
(Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect
on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage
sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but
affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral
systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献