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摘要：丹江口库区水源涵养林林分质量和生态功能的高低严重制约着我国南水北调中线工程建设成效。笔者通过对丹江口库区水源涵养林不同典型林分调查和研究,针对各类型林分现状和所存在的问题,基于近自然经营的理念和方法,提出了相应林分近自然改造措施,为丹江口库区水源涵养林的可持续经营提供依据。 相似文献
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中国林业传统与林业文化 总被引：5，自引：0，他引：5
本文用两分法，将中国林业传统分为保护森林、合理利用森林资源的传统和破坏森林、大量消耗林木的传统。前者是以对动、植物的图腾崇拜为开端；后者是以火的使用为开端。在两种传统的形成与发展中，产生了丰富多彩并具有中国特色的林业文化，包括各类树木及竹文化、花卉文化、园林文化和岩栖山居与森林游乐文化等。 相似文献
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腾油12号是从腾冲红花油茶天然林分中选择优树,优树无性系化后采用随机区组试验设计28处理5重复选育的优良无性系品种。其主干明显,幼树期生长势较强,多品种混栽自然坐果率为80．7％;10月上中旬成熟,平均单果质量为62g,种子出仁率达71．0％,仁出油率达51．4％;籽油含不饱和脂肪酸84．5％,油酸74．96％。其开始结果早,丰产,种植后第六年进入经济收益期,平均产粗油406．5kg／hm^2,为对照的13．5倍。阐述建园、土肥水管理、整形、修剪等栽培技术要点。 相似文献
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Small seasonally flooded forest ponds have received increased attention due to a growing recognition of their abundance in many landscapes, their importance as habitat for a variety of organisms, and the contributions they make to species and ecosystem diversity. There also is concern over potential negative effects of forest management in adjacent uplands on seasonal pond ecology. Several studies have examined invertebrate and songbird responses to upland harvest around seasonal ponds. Less attention has been given to examining how seasonal pond plant communities respond to adjacent forest harvesting. We studied the response of seasonal pond plant communities to adjacent upland timber harvests, assessing whether buffers around ponds (15.25 m uncut and partially cut) mitigated changes in species abundance and community composition, relative to changes in ponds that were clearcut to the pond margin. We addressed our objective using an operational-scale experiment in northern Minnesota, which included pre-harvest sampling, replicated treatments, and uncut controls. After treatment, changes in tree basal area and canopy openness in the pond basins reflected reductions in upland basal areas. Specifically, control ponds had significantly higher basal area and lower openness than ponds cut to their margins, while ponds with uncut buffers and partially cut buffers were intermediate. Changes in plant communities were evident in the ground layer and shrub/large regeneration layer. After treatment and over time, the control stands did not change significantly in ground layer structure or shrub/large regeneration layer composition. The three upland harvest treatments displayed increasingly greater deviation from their starting conditions and from the control along a gradient of increasing treatment intensity, from the buffer treatment to the partially cut buffer to the clearcut. The response in the ground layer was largely associated with increased sedge and grass cover, while the response in the shrub/large regeneration layer was associated with increases of Salix sp., Alnus incana, and Populus tremuloides. Our results indicate that adjacent upland timber harvest can lead to altered plant communities within seasonal ponds, at least temporarily. Moreover, uncut forest buffers (∼15.25 m) surrounding seasonal ponds can mitigate plant community changes to some degree. If seasonal ponds are an important resource on the management landscape and a high percentage of upland forest is in a recently cut condition at any given time, than use of harvest buffers around seasonal ponds may be an appropriate approach for mitigating short term alteration of pond plant communities. 相似文献
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In eastern North Carolina, USA, intensively managed pine (Pinus spp.) forests, a primary forest type in the Southeastern United States, often are established where water levels are maintained via ditching. In these landscapes, water occurs in numerous linear ditches and several small ponds (heliponds), used by helicopters for the suppression of forest fires. Changes to the physical structure of water sources may be important to bats that use these sources for drinking and foraging. Therefore, we examined bat activity in a managed pine landscape and an adjacent natural wetland in relation to water source type (heliponds, ditches, and natural wetland) and insect abundance. We sampled bat activity using remote acoustic detectors; we sampled insects using passive traps. Insect abundance did not differ among water source types. Bat activity was most concentrated at modified water sources within the managed pine landscape (heliponds and ditches). Feeding activity was highest at heliponds. Heliponds and ditches were important sources of open water and insect prey for bats in the managed pine forest landscape. We suggest management for bats in similar forest landscapes should include maintenance of open and accessible water sources such as heliponds. 相似文献
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殷墟为晚商时期的都城遗址,已考古发掘出大量的宫殿、陵墓、手工业作坊、路网及水网等遗迹,很多学者也展开了相关研究.对我国近20年来有关晚商殷墟池苑研究的文献资料进行梳理,发现晚商时期殷墟地区气候温和湿润,具备营造园林的社会、经济和技术条件,再结合建筑、水体等池苑构成要素及池苑功能方面的文献资料得出以下推论:晚商殷墟池苑是... 相似文献
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H. von Pechmann 《European Journal of Forest Research》1971,90(1):224-235
Summary The very quick rise of mining, salt-production, oretrade and metal-industrie caused in the 16. century an enormous need in
wood and charcoal, added to this the consumption of firewood in the cities, the need of wood for glassworks and various woodworkers
and of timber for a raising population. Floats on the rivers were the most important transport means for commerce as well
as for travelling.
The economic structure-changes at the end of the Middle Ages led to a high valuation of the forests as most important raw
material reserves. It showed itself in the effort of the state-authorities to preserve the growingstock; restrict the customary
forest utilizations and to orderly management of the forests against the opposition of the farmers, who stuck to their old
customary rights. The beginning of a forest literatur as well as a great number of forest orders contain progressive instructions
for prevention and care of the forests.
Moreover the new appreciation of nature, plants and trees produced splendid gardens and the first paintings emphasizing landscapes
and forests.
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从德国“可持续”森林利用的不同概念、德国不同森林认证体系“经营标准(Management Standards)”的比较实例、德国森林经营和“近自然森林经营”筒史、德国森林资源状况和森林资源的变化、德国有关森林资源的几个基本理念与“近自然森林经营”的主要特征、德国哥廷根市有林“近自然森林经营”实例等6个方面,简要介绍了德国的“近自然森林经营”。 相似文献
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2006年四川发生了百年一遇的特大干旱。按照自然地理条件相近、森林覆盖率有较大差异的原则,采用对比分析方法,于干旱末期,调查了四川盆地丘陵区13对乡镇(森林覆盖率高的乡镇森林覆盖率为28.26%～56.23%,平均为38.22%,相对应的低的乡镇森林覆盖率为5.65%～27.10%,平均为16.41%)内的溪河流量、堰塘和水井干枯情况以及人畜饮水现状。结果表明,在干旱季节,森林覆盖率低的乡镇溪河断流率平均为69.1%,断流天数平均为52 d;而覆盖率高的乡镇溪河断流率平均为25.5%,比前者少43.6%,断流天数平均为35.3 d,比前者少16.7 d,溪河平均断流起始时间比前者推迟17.3 d。森林覆盖率低的乡镇堰塘、水井平均干枯率分别为62.5%、70.0%,新打水井中,出水井率为48.2%;而覆盖率高的乡镇堰塘、水井平均干枯率分别为40.9%、43.7%,比前者分别低21.6%、26.4%,新打水井中,出水井率为57.7%,比前者高出9.5%。人畜饮水困难数占总人畜比例,覆盖率高的乡镇比覆盖率低的乡镇分别少24.0%、23.2%。 相似文献
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《中国林学(英文版)》2006,8(1):I0001-I0001
Forestry Studies in China strives to provide a platform for a broad blend of peer-reviewed papers for a purpose of accelerating academic communication and exchanges between forestry researchers in and outside China. The Journal features articles by international scientists across the spectrum of forest research, including forest ecology, silviculture, forest management, sci- 相似文献
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《中国林学(英文版)》2007,9(4):F0002-F0002
Forestry Studies in China strives to provide a platform for a broad blend of peer-reviewed papers for a purpose of acceler-ating academic communication and exchanges between forestry 相似文献
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《中国林学(英文版)》2010,(4):164-F0002
Forestry Studies in China strives to provide a platform for a broad blend of peer-reviewed papers for a purpose of accelerating academic communication and exchanges between forestry researchers 相似文献
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Viruses were detected in water samples collected from two forest districts of NorthrhineWcstfalia in early spring 1985 and 1986. Mechanically transmissible viruses of the Tobamo Potex- and Tombusvirus groups were isolated from 39 of 66 water samples taken from creeks, ponds and drainage ditches. 相似文献
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Elizabeth A. Roznik Steve A. Johnson Cathryn H. Greenberg George W. Tanner 《Forest Ecology and Management》2009
Many animals exhibit changes in patterns of movement and habitat use as they age, and understanding such ontogenetic shifts is important for ensuring that habitat management is appropriate for all life stages. We used radiotelemetry to study movements and habitat use of juvenile and adult gopher frogs (Rana capito) as they migrated from the same ponds following metamorphosis or breeding. To supplement radiotelemetry data, we also captured adult gopher frogs at drift fences as they left ponds for the terrestrial environment. We directly compared patterns of movement, directional orientation, macrohabitat use (forest type), and microhabitat use (refugia) between the two life stages. Both juveniles and adults moved considerable distances from breeding ponds (up to 691 m) and selected fire-maintained longleaf pine (Pinus palustris) forest over fire-suppressed forest. However, fire-suppressed habitat appeared to be a greater barrier to juveniles than adults. Additionally, we found differences in microhabitat use; both juveniles and adults used underground refuges (e.g., burrows and stump holes) for shelter, but juveniles used such refuges less often than adults. Juveniles also took more time than adults to locate their first refuge after exiting ponds. These differences may reflect the juveniles’ lack of experience in terrestrial habitats. Unlike juveniles, adults are likely more familiar with the locations of specific habitat features (e.g., burrows and ponds) and may take the shortest routes when moving among them, even if it requires moving through fire-suppressed habitat. Previous research has recommended that terrestrial habitats surrounding breeding ponds should be managed with frequent prescribed fire (i.e., 1–3-year intervals) in order to maintain suitable terrestrial habitat for juvenile gopher frogs, and our study suggests that these management practices are also likely beneficial to adults. 相似文献
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美国森林管理的特点与启示 总被引：1，自引：0，他引：1
通过实地考察,总结了美国森林管理具有严格管理公有森林、鼓励发展私有林业、实行森林集约经营、科学治理沙漠土地、高度重视城镇绿化、重视生态系统保护、依法管理森林行为等七大特点。并以此为鉴,坚持从实际出发,提出我国森林经营管理必须重视强化的六个环节:必须用法律手段调整森林经营行为;切实用生态系统管理理念指导森林经营活动;加大对天然林资源的保护管理力度;坚持把林木种苗生产管理作为森林经营的首道工序来抓;争取把自然保护区和森林公园纳入自然文化遗产管理;努力为非公有制林业发展创造宽松环境。 相似文献