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1.
本文对两期遥感图像进行解译，并在GIS支持下提取露水河林业局主要河流两岸各缓冲区森林资源信息，经分析得到各类地物在1985年及1999年的变化趋势。结果表明：在河流沿岸对森林的采伐强度1999年较1985年明显减小，整体生态环境较1985年有所改善。在缓冲区1，2，3除中龄针叶林大幅度增加外，其它地物类型面积均减少，由此可以看出，在这三个缓冲区内针叶林得到了较好的恢复。在缓冲区4内，中龄针叶林、成熟针叶林、成熟阔叶林形成一个林龄梯队，有利于森林生态系统的稳定与功能的发挥，十五年间缓冲区4受到的干扰相对较小。湿地数量在四个缓冲区内均有所减少，虽然在缓冲区4内森林生态系统恢复的较好，但湿地面积仍有所减少，说明保护及恢复湿地资源是一件非常艰巨的任务，必须引起高度重视。图5表2参12。 相似文献
2.
The creation of riparian forest buffer zones for water quality management in agricultural landscapes takes land out of production,
incurring an economic loss for the landowner. However, planting and harvesting techniques, such as those employed in indigenous
systems of tropical agroforestry, can enhance riparian forest buffer strips with economically viable species. This kind of
riparian forest buffer can be harvested and generate income from otherwise unproductive tracts of land. This practice would
make the implementation of riparian forest buffers more acceptable to farmers, by generating income while helping to improve
water quality. The present project provides an economic model for the harvest of non-timber products (fruits, nuts and ornamentals)
from riparian forest buffer zones in the Chesapeake Bay region. Potential gross income from harvest is calculated to demonstrate
the feasibility of this strategy. Given certain assumptions, the gross income can amount to $60,934.30/ha/year.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
基于28个20mx90m样地的调查数据,利用Lotka-Volterra模型,本文分析了长白山北坡阔叶红松(Pinuskoraiensis)林和云冷杉林(也叫暗针叶林)群落交错区优势树种之间的竞争及动态。结果显示:在自然条件下,群落将向两个方向分化,一是以云杉(PiceajezoensisandP.koraiensis)和冷杉(Abiesnephrolepis)为优势的群落,并在达到平衡时冷杉占绝对优势(相对优势度的77.1%):另一种是以红松或云冷杉和阔叶树占绝对优势的针阔混交林,并在达到平衡时,阔叶树在阔叶红松林中占相对优势度的50%,在云冷杉一阔叶林类型中占66%。同时,本研究说明:(1)阔叶红松林和云冷杉林都是长白山气候顶极群落:(2)交错区具有过渡性质:(3)森林群落的分化结果说明演替的方向受局部生境的影响。图1表3参24。 相似文献
4.
Vegetation structure,composition and effect of pine plantation harvesting on riparian buffers in New Zealand 总被引：1，自引：0，他引：1
The composition and structure of vegetation within riparian buffers prior to, and immediately post-harvesting in a managed radiata pine (Pinus radiata D.Don) forest is described and compared with riparian buffers in residual adjoining native forest on the Coromandel Peninsula, New Zealand. One hundred and twenty-one species (71% native) representing life forms from grasses to trees were recorded. The highest species richness, including both native and adventive (non-native) species, was found in riparian buffers in the post-harvest and native reference sites which had 18–25 species per site. Riparian buffers in mature pine plantations contained a mix of native species that was generally similar to, and not significantly reduced in species richness, from the reference native forest. Native species comprised 82–92% of the total cover in mature pre-harvest sites (irrespective of riparian width), and 99.8% in native reference sites. Compared with native forest the principal difference was a reduction of total cover in the upper tiers (5–12 m), and some increase in cover in the lower tiers. Adventive species in post-harvest sites comprised 16–67% of the total cover and were most frequently found in riparian areas highly disturbed by recent harvesting of the pines, particularly where riparian buffers were narrow or absent. Invasion by light-demanding adventives is expected to be temporary and most species are likely to be shaded out as the new rotation of pine trees develops. Radiata pine plantations in Whangapoua Forest can provide suitable conditions for the development of riparian buffer zones that will become dominated by native species, similar in richness and structure to neighbouring native forest. 相似文献
5.
Daxing'an Mountains was one of the most important forest areas in China, but it was also an area which was prone to suffering
forest fire. The catastrophic forest fire that occurred in Daxing'an Mountains on May 6, 1987 devastated more than 1.33×106 hm2 of natural forests, which leaded to the formation of some mosaic areas with different burn intensities. Two forest farms
of Tuqiang Forest Bureau (124°05′–122°18′E, 53°34′–52°15′N) were chosen as a typical area to analyze the post-fire landscape
change by drawing and comparing the two digital forest stand maps of 1987 and 2000. The landscape lands of forest were classified
into 12 types: coniferous forest, broadleaf forest, needle-broadleaf mixed forest, shrub, nursery, harvested area, burned
blanks, agricultural land, swamp, water, built-up, grass. The results showed that: 1) The burned blanks was almost restored,
some of them mainly converted into broadleaf forest land during the process of natural restoration, and coniferous forest
land by the artificial reforestation, and the others almost changed into swamp or grass land; 2) The proportion of forest
area increased from 47.6% in 1987 to 81.3% in 2002. Therefore, a few management countermeasures, such as the enhancing people's
consciousness of fire-proofing and constructing species diversity, were put forward for forest sustainable development.
Foundation item: Under the auspices of the National Science Foundation of China (No. 30270225, 40331008) and the Chinese Academy of Sciences
(SCXZY0102).
Biography: KONG Fan-hua (1975-), female, Ph.D. candidate of Hiroshima University in Japan, specialized in Landscape Ecology.
Responsible editor: Zhu Hong 相似文献
6.
我国主要森林生态系统类型降水截留规律的数量分析 总被引：92，自引：0，他引：92
通过对大量林林生态系统水文生态功能研究资料的分析，从林冠层、枯枝落叶层和土壤三个森林水文生态功能的发挥最主要的层次出发，比较分析了我国主要森林生态系统类型的降水截留规律。 相似文献
7.
Sara A. Berges Lisa A. Schulte Moore Thomas M. Isenhart Richard C. Schultz 《Agroforestry Systems》2010,79(1):97-110
In response to concern about the loss of ecosystem services once provided by natural riparian systems, state and federal agencies
have established incentive programs for landowners to convert sensitive lands from agricultural to conservation uses. Enhancement
of wildlife habitat, while identified as a function of such systems, has often been of secondary importance to soil conservation
and water quality objectives. Though greatly important, little consideration has been given to how specific species will respond
to the design and management of riparian buffers or other conservation lands. This study compared avian communities within
a chronosequence of riparian buffers established on previously cropped or pastured land with those of the nearby matrix land
cover types (row crop fields and an intensively grazed pasture). The riparian buffers consisted of native grasses, forbs,
and woody vegetation established at three different times (2, 9, and 14+ years prior to survey). At each site, 10 min point
counts for breeding birds were conducted using 50 m fixed radius plots, which were visited eight times between May 15 and
July 10, 2008. A total of 54 bird species were observed over all of the study sites. The re-established riparian buffers in
this study had higher bird abundance, richness, and diversity than the crop and pasture sites. These results suggest that
re-establishing native riparian vegetation in areas of intensive agriculture will provide habitat for a broad suite of bird
species, but that specific species will reflect successional stage, horizontal and vertical vegetative structure, and compositional
diversity of the buffer vegetation. These results emphasize the importance of matching buffer design and management to species
requirements if the objectives are to attract specific target species or species groups. 相似文献
8.
Matthew R. Kluber Deanna H. Olson Klaus J. Puettmann 《Forest Ecology and Management》2008,256(4):529-535
Over the past 50 years, forested landscapes of the Pacific Northwest have become increasingly patchy, dominated by early successional forests. Several amphibian species associated with forested headwater systems have emerged as management concerns, especially after clearcutting. Given that headwater streams comprise a large portion of the length of flowing waterways in western Oregon forests, there is a need to better understand how forest management affects headwater forest taxa and their habitats. Mitigation strategies include alternatives to clearcutting, such as harvests that remove only part of the canopy and maintenance of riparian buffer strips. Our study investigates effects of upland forest thinning coupled with riparian buffer treatments on riparian and upland headwater forest amphibians, habitat attributes, and species-habitat associations. Amphibian captures and habitat variables were examined 5–6 years post-thinning within forest stands subject to streamside-retention buffers and variable-width buffers, as well as unthinned reference stands. We found no treatments effects, however, our results suggest that ground surface conditions (e.g., amount of rocky or fine substrate) play a role in determining the response of riparian and upland amphibians to forest thinning along headwater streams. Distance from stream was associated with amphibian abundance, hence retention of riparian buffers is likely important in maintaining microclimates and microhabitats needed for amphibians and other taxa. Moderate thinning and preservation of conditions in riparian and nearby upland areas by way of variable-width and streamside-retention buffers may be sufficient to maintain suitable habitat and microclimatic conditions vital to amphibian assemblages in managed headwater forests. 相似文献
9.
Nutrient Attenuation in Agricultural Surface Runoff by Riparian Buffer Zones in Southern Illinois,USA 总被引：1，自引：0，他引：1
Nutrients in overland flow from agricultural areas are a common cause of stream and lake water quality impairment. One method
of reducing excess nutrient runoff from non-point sources is to restore or enhance existing riparian areas as vegetative buffers.
A field scale study was conducted to assess the ability of remnant giant cane (Arundinaria gigantea (Walt.) Muhl.) and forest
riparian buffer zones to attenuate nutrients in agricultural surface runoff from natural precipitation events. Two adjacent,
10.0 m wide riparian buffers were instrumented with 16 overland flow collectors to monitor surface runoff for nitrate, ammonium,
and orthophosphate. Measurements were taken at 3.3 m increments within each buffer. The forest buffer significantly reduced
incoming dissolved nitrate-N, dissolved ammonium-N, total ammonium-N, and total orthophosphate masses in surface runoff by
97, 74, 68, and 78 , respectively within the 10.0 m riparian buffer. Nutrient reductions within the cane buffer were 100 for
all three nutrients due to relatively high infiltration rates. Significant reductions of total ammonium- N and total orthophosphate
were detected by 3.3 m in the cane buffer and at 6.6 m in the forest buffer. Results suggest that both giant cane and forest
vegetation are good candidates to incorporate into riparian buffer restoration designs for southern Illinois as well as in
other regions within their native range with similar climatic and physiographic conditions. 相似文献
10.
风对林木的影响 总被引：7，自引：0，他引：7
风除对森林造成了危害外,还对树木的生长、形态以及森林生态等产生影响。随着全球气候变化的发展,更多和更强的暴风出现的危险性日益增加。为了更好地理解风害对树木、林分和森林生态系统的影响,为森林经营管理提供依据,本文对近10年来国际上有关风对林木影响内容进行归纳总结。结果表明,风对林木影响的研究主要在以下几个方面取得了重要的进展：1)风与林木的空气动力学关系;2)树木在风力荷载下其适应性的生长机理;3)树木对风的生理响应：4)森林风害的危险评估。所有这些研究大都在人工用材林中进行的。此外,本文还介绍了该研究领域需要开展的其它研究,如1)天然林或天然次生林的风害研究;2)风害形成的林窗和森林动态研究;3)风害对森林生态主要过程的影响研究;4)．风害与森林管理研究。图3参61。 相似文献
11.
Picea mongolica is an endemic and endangered species in China. Ecosystem made ofPicea mongolica is a special sandy forest ecosystem in China. It is found at ecotone between forest and steppe, or agricultural district
and pas toral area. Based on investigation, this paper discussed the formation and distribution ofPicea mongolica and studied its nature according to ecotone theory. It is clarified thatPicea mongolica belongs toPicea meyeri series. That is to say, it became a local race through long-term adaptation to the local climate, then formed allopatric
semi-species, and finally turned into a taxonomical species.Picea mongolica forest is a super zonal climax community developing in ecotone between forest zone and steppe zone.
Foundation item: The study was supported by National Natural Science Foundation of China (39670133, 39900019, 30070129).
Biography: ZOU Chun-jing (1968-), male, Ph.D, associate researcher fellow in Institute of Applied Ecology, Chinese Academy of Science,
Shenyang 110015, P. R. China
Responsible editor: Chai Ruihai 相似文献
12.
ZHU Jiao-jun KANG Hong-zhang TAN Hui XU Mei-ling WANG Jun 《林业研究》2005,16(4):253-259
Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China （the original of the natural Mongolian pine, forest on sandy land） was studied in 2004. The total mean values of regeneration indexes were higher in mature stands （more than 80% individual stems were older than 50 years）, the maximum of regeneration index reached 29 seedlings, m^ 2, with lowest values in the younger stand, e.g., in 32-year old and 43-year old stands. The stand age was an important factor determining the natural regeneration, which was the best in the older stands in this investigation （e.g. about 80-year old）. The regeneration index seemed not to be closely in relation to canopy openness although Mongolian pine is a photophilic tree species. In each type of gaps, natural regeneration was very well. Regeneration indexes were satisfactory at the south and east edges in the circle gaps; and at the east edge of the narrow-square gaps. Results indicated that Mongolian pine, seedlings could endure shading understory, but it would not enter the canopy layer without gap or large disturbance, e.g., fire, wind/snow damage or clear cutting etc. These results may provide potentially references to the management and afforestation of Mongolian pine, plantations on sandy land in arid and semi-arid areas. Researches such as the comprehensive comparisons on regeneration, structure and ecological conditions and so on between natural Mongolian pine, forests and plantations should be conducted in the future. 相似文献
13.
Jon E. Schoonover Karl W. J. Williard Chris Blattel Chad Yocum 《Agroforestry Systems》2010,80(1):97-107
Across the U.S., multiple species of riparian vegetation have proven to be effective filters of sediment and nutrients in
agricultural watersheds. Research at Southern Illinois University Carbondale has focused on giant cane [Arundinaria gigantea (Walt.) Muhl.] as a potential candidate to incorporate into riparian buffer designs. In 2001, an exploratory study (i.e.,
Phase I) monitored nutrient and sediment concentrations from surface runoff and groundwater in the Cypress Creek watershed,
while two subsequent studies (i.e., Phase II) focused on groundwater quality and added additional riparian buffer plots in
the Big Creek and Cache River Watersheds. The primary objective of this research was to compare nutrient attenuation in groundwater
of native giant cane and forest riparian buffers. Results from phase I showed significant nutrient reductions in groundwater
over short distances in both the giant cane (~3.0 m) and forest buffers (~6.0 m), thus additional wells were installed at
1.5 and 12.0 m for the second phase. Groundwater NO3
−-N was significantly reduced by 90% in the initial 3.0 m of the giant cane buffer, where plant assimilation and microbial
denitrification were likely key NO3
−-N removal mechanisms. Phase II showed significant reductions in groundwater NO3
−-N beneath the forest buffers, whereas little change occurred below the giant cane buffers. However, NO3
−-N concentrations beneath giant cane buffers were 3 times less than those observed beneath the forest buffers. Follow-up studies
are being conducted on the transport of E. coli through vegetated buffers, and efforts have been expanded to the watershed-scale. 相似文献
14.
Forest riparian buffers are an important means of conserving land. The Conservation Reserve Enhancement Program (CREP) offers
financial incentives to landowners to install forested riparian buffers under 10–15 year contracts. This study explores whether
Pennsylvania CREP participants who had established a riparian buffer would also place it under a permanent conservation easement.
A mail questionnaire was developed and administered to 685 CREP participants. It was found that the majority of the respondents
are likely to leave their buffer intact when the CREP contract expires, but are hesitant to agree to conservation easements.
Property rights, education and finances are among the key issues affecting acceptance of conservation easements. 相似文献
15.
长白山北坡植物群落复杂性的海拔梯度变化 总被引：2，自引：0，他引：2
应用梯度格局法在长白山北坡海拔700m-2600m的坡面上每100 m海拔设置一样地,共计20块样地,通过对同一群落各样方间的相异性测定,对各海拔植物群落的复杂性进行了分析。结果表明,以主林层乔木种的二元数据计算的结果,除亚高山岳桦林外,其它各海拔群落的样方间均表现出较高的相异性,特别是低海拔的阔叶红松林平均相异系数达0.74,明显高于其它植被类型;暗针叶林各群落间差异不大,相对而言1400 m群落样方间的相异性略高于其它群落,表现出过渡性群落树种组成的复杂性;岳桦林树种组成简单,样[(\267\275\274\344\322\262\261\355\317\326\263\366\275\317\270\337\265\304\\317\340\313\306\320\324\241\243)-0.1(\322\324\271\340\304\276\326\326\265\304\266\376\324\252\312\375\276\335\\274\306\313\343\265\304\310\272)]落内的相异性,虽低海拔的阔叶红松林总体上高于其它群落,但差异趋势并不像乔木种那么明显。以各草本植物与所有植物种的二元数据计算的各海拔群落内样方间的相异性,表现出非常相近的趋势,群落内样方间草本植物及所有植物种均以阔叶红松林及高山冻原差异最大,暗针叶林基本稳定于比较相近的水平。图3表1参8。 相似文献
16.
Vertical variation and storage of nitrogen in an aquic brown soil under different land uses 总被引：3，自引：0，他引：3
The vertical variation and storage of nitrogen in the depth of 0–150 cm of an aquic brown soil were studied under 14 years
of four land use patterns, i.e., paddy field, maize field, fallow field and woodland in Shenyang Experimental Station of Ecology,
Chinese Academy of Sciences in November of 2003. The results showed that different land uses had different profile distributions
of soil total nitrogen (STN), alkali N, ammonium (NH4
+-N) and nitrate (NO3
−-N). The sequence of STN storage was woodland>maize field>fallow field>paddy field, while that of NO3
−-N content was maize field>paddy field>woodland>fallow field, suggesting the different root biomass and biological N cycling
under various land uses. The STN storage in the depth of 0–100 cm of woodland averaged to 11.41 t·hm−1, being 1.65 and 1.25 times as much as that in paddy and maize fields, respectively, while there was no significant difference
between maize and fallow fields. The comparatively higher amount NO3
−-N in maize and paddy fields may be due to nitrogen fertilization and anthropogenic disturbance. Soil alkali N was significantly
related with STN, and the correlation could be expressed by a linear regression model under each land use (R
2≥0.929,p<0.001). Such a correlation was slightly closer in nature (woodland and fallow field) than in agro ecosystems (paddy and maize
fields). Heavy N fertilization induced an excess of crop need, and led to a comparatively higher amount of soil NO3
−-N in cultivated fields than in fallow field and woodland. It is suggested that agroforestry practices have the potential
to make a significant contribution to both crop production and environment protection.
Foundation item: The project was supported by the Knowledge Innovation Program of Chinese Academy of Sciences (KZCX2-413-9) and Fund of Shenyang
Experimental Station of Ecology, CAS (STZ0204)
Biography: ZHANG Yu-ge, (1968-), female, Ph.D. candidate, associate research fellow in Institute of Applied Ecology, Chinese Academy
of Sciences, Shenyang 110016, P.R. China.
Responsible editor: Song Funan 相似文献
17.
土壤温度和水分对长白山3种温带森林土壤呼吸的影响 总被引：7，自引：0，他引：7
为了研究土壤温度和土壤含水量对阔叶红松林(山地暗棕壤)、云冷杉暗针叶林(山地棕针叶林土壤)和岳桦林(生草森林土)的土壤呼吸的影响,于2001年9月在长白山进行了土壤实验。利用增加土壤样柱的含水量,将土壤含水量分为9%,、21%、30%、37%和43%5个等级,土壤样品分别在0、5、15、25和35 的温度下保持24小时。阔叶红松林土壤在0~35 范围内,土壤呼吸速率与温度呈正相关。在一定的含水量范围内(21%~37%),土壤呼吸随含水量的增加而升高,当含水量超出该范围,土壤呼吸速率则随含水量的变化而降低。土壤温度和水分对土壤呼吸作用存在明显的交互作用。不同森林类型土壤呼吸作用强弱存在显著差异,大小顺序为阔叶红松林>岳桦林>云冷杉暗针叶林.红松阔叶林土壤呼吸作用的最佳条件是土壤温度35 ,含水量37%;云冷杉暗针叶林下的山地棕色针叶土壤呼吸作用的最佳条件是25 ,21%;岳桦林土壤呼吸作用的最佳条件是35 ,含水量37%。但是,由于长白山阔叶红松林,云冷杉林和岳桦林处在不同的海拔带上,同期不同森林类型土壤温度各不相同,相差4~5 ,所以野外所测的同期的山地棕色针叶林土呼吸速率应低于暗棕色森林土呼吸速率,山地生草森林土呼吸速率应高于山地棕色针叶林土的呼吸速率。图2表1参25。 相似文献
18.
In order to investigate the effect of invastion by pine wood nematode （PWN）, this study analyzed severalfunctional indices, i.e., the increment in DBH and stand volume and biomass, in the damaqed stands with various mixedpercentages of Pinus massoniana and P. thunbergii and with different levels of damage. According to the results of rate of change in increment of DBH and stand volume, the forest ecosystem resistance against PWN increased with a reduct on n the m xed ratio of pine. The resistance was highest with a mixed percentage of 50%. The invasion of PWN hanged the corresponding relationship of increment between DBH and stand volume （pure stands 〉 7：3 conifer and roadleaf 〉 6：4 conifer and broadleaf 〉 5：5 conifer and broadleaf） among the P. thunbergii stands when there is no amage, but for P. massoniana stands this phenomenon did not occur. For the increment rate of DBH and stand volume, is significant change in P, thunbergii forest indicates that the resistance of pure P. thunbergii forest was higher than at of P. massoniana. The invasion of PWN accelerates the succession from pure stands to mixed stands and then tohe broadleaf evergreen stands. 相似文献
19.
岷江上游景观格局变化研究(英文) 总被引：1，自引：0，他引：1
岷江上游地区位于青藏高原向四川盆地的过渡地段,其源头到都江堰市,包括汶川县、茂县、理县、黑水县和松潘县五个县。它是四川省乃至全国的一个重要的林区。在过去的几十年里,其景观结构发生了重要的变化。本文应用3S 技术研究了该区在1986 年到2000 年之间的景观变化情况。该区的景观被划分为10 个景观生态类型,即耕地、有林地、灌木林地、经济林、草地、居民用地、河流、湖泊、沼泽和未利用地。研究结果表明,在岷江上游地区林地和草地是该区主要的景观类型,约占全区面积的91%,景观类型之间的变化主要发生在有林地、灌木林地、草地、耕地、居民用地和经济林之间,并且有林地面积从51.17%下降到47.56%。分析结果表明,岷江上游地区在过去的几十年里其景观的破碎化在加剧。图1表2 参20。 相似文献