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森林景观是森林公园的主体,是森林公园开展生态旅游的物质基础.本文将森林公园的森林景观划分为三大功能:美化功能、生态功能和保健功能,并总结了三大功能的评价方法,最后提出相关建议.认为对森林景观的三大功能进行综合评价,能更合理地利用森林公园资源,有利于森林公园的生态旅游开发和可持续发展. 相似文献
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Kenneth W. Stolte 《人类与生态风险评估》2001,7(5):1297-1316
The Forest Health Monitoring (FHM) and Forest Inventory and Analyses (FIA) programs are integrated biological monitoring systems that use nationally standardized methods to evaluate and report on the health and sustainability of forest ecosystems in the United States. Many of the anticipated changes in forest ecosystems from climate change were also issues addressed in sections of FHM's National Technical Report 1991 to 1998. The integrated FHM and FIA monitoring systems are currently establishing baseline conditions (status and change) in most States for many of the expected effects, and are projected to have full implementation for all States and Territories in 2003. These monitoring systems utilize a broad suite of indicators of key ecosystem components and processes that are responsive to many biotic and abiotic stressors, including those anticipated from climate change. These programs will contribute essential information for many decades for many of the anticipated changes in forest ecosystem from increasing carbon dioxide concentrations, changing climatic scenarios, and extreme weather events that are probable in the next 30 to 100 years. 相似文献
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Wil de Jong 《Biotropica》2010,42(1):3-9
Forest transition theory bases its predictions of forest recovery in temperate regions primarily on macro-economic factors. In tropical countries, it is important to understand additional complex processes underlying forest recovery. Forest rehabilitation—meaning efforts to restore tree cover—is an important contributor to forest recovery in many tropical regions. Forest rehabilitation itself is subject to multiple factors that influence its scale, effectiveness and outcomes. This paper reviews forest rehabilitation in six countries—Brazil, China, Indonesia, Peru, Philippines and Vietnam. The cases reviewed suggest that globally, forest rehabilitation efforts can be understood in four time periods, or eras, each with distinct approaches to forest rehabilitation and outcomes. Various factors that influence forest rehabilitation outcomes evolved during these eras. Current outcomes of forest rehabilitation can only be adequately predicted if the historical processes influencing forest rehabilitation are understood. The paper suggests that forest transition in the tropics needs to be analyzed not only in terms of macro-economic factors, but also in terms of the factors that influence forest rehabilitation outcomes as well as other processes that affect forest cover increase. 相似文献
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Forest tree biotechnology 总被引:12,自引:0,他引:12
The past year has seen the fruits of biotechnological manipulation of forest trees approach commercial application. Advances in somatic embryogenesis have brought mass clonal propagation of the top commercial trees closer to reality, and efficient gene transfer systems have been developed for a number of conifers and hardwoods. Radical alterations in the quantity and quality of lignin in wood have been shown to be possible in softwoods and hardwoods through identification of naturally occurring mutants, as well as by engineering the lignin biosynthetic pathway with transgenes. The potential environmental and social impacts of the release of transgenic trees have become an increasingly contentious issue that will require more attention if we are to use these technologies to their full advantage. 相似文献
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Aboveground forest structure, biomass, and primary productivity in a tropical heath forest in Central Kalimantan (Indonesian Borneo) were examined using data from 1-ha plots and stand-level allometric equations developed from harvested tree samples. The study site experienced a severe drought in 1997–1998 associated with the El Niño Southern Oscillation event. The drought effect on heath forest productivity was also assessed by evaluating changes in wood mass increment rates. Allometric relationships suggested that heath forest trees had leaves with smaller specific leaf area (SLA), and large heath forest trees allocate more to leaf mass compared to mixed dipterocarp forest trees. Aboveground biomass (for trees ≥ 4.8 cm DBH) in two 1-ha plots, P1 and P4, totaled 244.8 and 232.0 Mg/ha. Aboveground wood mass increment rate was –0.1 and 4.7 Mg/ha/yr in P1 and P4 during the drought period (from February to August 1998), while it quickly recovered to 8.1 and 8.5 Mg/ha/yr during the post-drought period (from August 1998 to August 1999 for P1 and from August 1998 to November 1999 for P4). This suggests a severe impact of the drought on heath forest productivity. Leaf characteristics of heath forest such as small SLA and long-lived leaves probably play a significant role in effective assimilation and maintenance of heath forest productivity under stressful conditions. 相似文献
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Leandro Da Silva Duarte Rodrigo Scarton Bergamin Vinícius Marcilio-Silva Guilherme Dubal Dos Santos Seger Márcia Cristina Mendes Marques 《PloS one》2014,9(8)
Phylobetadiversity is defined as the phylogenetic resemblance between communities or biomes. Analyzing phylobetadiversity patterns among different vegetation physiognomies within a single biome is crucial to understand the historical affinities between them. Based on the widely accepted idea that different forest physiognomies within the Southern Brazilian Atlantic Forest constitute different facies of a single biome, we hypothesize that more recent phylogenetic nodes should drive phylobetadiversity gradients between the different forest types within the Atlantic Forest, as the phylogenetic divergence among those forest types is biogeographically recent. We compiled information from 206 checklists describing the occurrence of shrub/tree species across three different forest physiognomies within the Southern Brazilian Atlantic Forest (Dense, Mixed and Seasonal forests). We analyzed intra-site phylogenetic structure (phylogenetic diversity, net relatedness index and nearest taxon index) and phylobetadiversity between plots located at different forest types, using five different methods differing in sensitivity to either basal or terminal nodes (phylogenetic fuzzy weighting, COMDIST, COMDISTNT, UniFrac and Rao’s H). Mixed forests showed higher phylogenetic diversity and overdispersion than the other forest types. Furthermore, all forest types differed from each other in relation phylobetadiversity patterns, particularly when phylobetadiversity methods more sensitive to terminal nodes were employed. Mixed forests tended to show higher phylogenetic differentiation to Dense and Seasonal forests than these latter from each other. The higher phylogenetic diversity and phylobetadiversity levels found in Mixed forests when compared to the others likely result from the biogeographical origin of several taxa occurring in these forests. On one hand, Mixed forests shelter several temperate taxa, like the conifers Araucaria and Podocarpus. On the other hand, tropical groups, like Myrtaceae, are also very representative of this forest type. We point out to the need of more attention to Mixed forests as a conservation target within the Brazilian Atlantic Forest given their high phylogenetic uniqueness. 相似文献
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Spatial ecological patterns reflect the underlying processes that shape the structure of species and communities. Mechanisms like intra- and inter-specific competition, dispersal and host-pathogen interactions can act over a wide range of scales. Yet, the inference of such processes from patterns is a challenging task. Here we call attention to a quite unexpected phenomenon in the extensively studied tropical forest at the Barro-Colorado Island (BCI): the spatial deployment of (almost) all tree species is statistically equivalent, once distances are normalized by ℓ0, the typical distance between neighboring conspecific trees. Correlation function, cluster statistics and nearest-neighbor distance distribution become species-independent after this rescaling. Global observables (species frequencies) and local spatial structure appear to be interrelated. This "glocality" suggests a radical interpretation of recent experiments that show a correlation between species'' abundance and the negative feedback among conspecifics. For the forest to be glocal, the negative feedback must govern spatial patterns over all scales. 相似文献
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温带次生林破碎化对白眉姬鹟繁殖的影响 总被引:1,自引:0,他引:1
于2005~2006年鸟类繁殖季节,通过悬挂人工巢箱,探讨了次生林破碎化对白眉姬鹟Ficedula zanthopygia繁殖的影响.结果 表明:次生林破碎化对白眉姬鹟繁殖产生很大的影响,斑块面积、形状指数、隔离度均在不同程度上影响着白眉姬鹟的繁殖参数,破碎化指数不同的斑块间白眉姬鹟的窝卵数、孵化率和出飞率差异均不显著(P>0.05);卵重变异很大,差异显著(P<0.05);卵体积变动更大,差异达到极显著水平(P<0.01).回归分析表明,斑块破碎化指数与白眉姬鹟繁殖参数间均存在一元二次方程关系:当窝卵数达到最大值时,卵质量降低,出雏率达到最低,雏鸟存活率反而增大,出飞率达到最大,从而提高繁殖功效;当窝卵数达到最小值时,卵质量最高,出雏率增大,出飞率也相应的增高,从而使繁殖功效增大.白眉姬鹟存在一个最优窝卵数,验证了Lack的窝卵数假说.另外,白眉姬鹟通过对自身繁殖参数的调节来适应生境破碎化,尽量提高自身的繁殖功效,从而弥补自身种群. 相似文献
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The quantity of litter-fall and the standing crop of H sublayer in the forest floor of evergreen broad-leaved forest were higher than that of Pinus yunnanensis forest. The quantity of the forest floor changed with the quantity of litter-fall, and thera was a dynamic equilibrium between the litter-fall and forest floor. The content of nutrient elements of the forest floor was higher than that of litter-fall in both types. The order of nutrient element content in the forest floor differed from that in litter-fall. In the evergreen broad-leaved forest, the order was N > Ca > Si>K>Mg>Al>P>Fe>Mn>Zn>Cu,and in Pinus yunnanensis forest it was Ca>N>Si>K>Al>Mg >Fe>P>Mn>Zn>Cu. But the order of nutrient element content in the forest floor had changed: in evergreen broad-leaved forest it was Si > N > Al > Ca > Fe > K>Mg>P>Mn>Zn>Cu, the Pinus yunnanensis forest it was Si > AI>N>Ca>Fe>K>M>P>Mn>Zn>Cu. With increase in the intensity of litter decomposition Ash, Si and Al had obviously increased, N, Fe, P and K had also increased in varying degrees, but there was some reduction in Ca, Zn and Mg. The ratio of carbon and nitrogen in litter decreased' with increase in litter decomposition. 相似文献
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Seed Banks in Savanna,Forest Fragments,and Continuous Forest Edges Differ in a Tropical Dry Forest in Madagascar
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Kim Valenta Travis S. Steffens Radoniaina R. Rafaliarison Colin A. Chapman Shawn M. Lehman 《Biotropica》2015,47(4):435-440
Rapid deforestation has fragmented habitat across the landscape of Madagascar. To determine the effect of fragmentation on seed banks and the potential for forest regeneration, we sampled seed viability, density and diversity in 40 plots of 1 m2 in three habitat types: forest fragments, the near edge of continuous forest, and deforested savanna in a highly fragmented dry deciduous forest landscape in northwestern Madagascar. While seed species diversity was not different between forest fragments and continuous forest edge, the number of animal‐dispersed seeds was significantly higher in forest fragments than in continuous forest edge, and this pattern was driven by a single, small‐seeded species. In the savanna, seeds were absent from all but three of the 40 plots, indicating that regeneration potential is low in these areas. Several pre‐ and post‐dispersal biotic and abiotic factors, including variation in the seed predator communities and edge effects could explain these findings. Understanding the extent to which seed dispersal and seed banks influence the regeneration potential of fragmented landscapes is critical as these fragments are the potential sources of forest expansion and re‐connectivity. 相似文献
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ADAM D. MORRIS DARREN A. MILLER MATINA C. KALCOUNIS-RUEPPELL 《The Journal of wildlife management》2010,74(1):26-34
ABSTRACT Forest edges often have increased species richness and abundance (edge effect) and affect spatial behaviors of species and dynamics of species interactions. Landscapes of intensively managed pine (Pinus spp.) stands are characterized by a mosaic of patches and linear forest edges. Managed pine forests are a primary landscape feature of the southeastern United States, but the effects of intensive management on bat communities are poorly understood. Insectivorous bats are important top predators in nocturnal forest food webs. We examined bat foraging behavior along forest edges and in 4 structurally distinct stand types (open-canopy pine, prethinned pine, thinned pine, and unmanaged forest) within a managed pine forest in the coastal plain of North Carolina, USA. During May-August, 2006 and 2007, we recorded echolocation calls using Pettersson D240X bat detectors linked to digital recorders at 156 sites. We also sampled nocturnal flying insects at each site using Malaise insect traps. We used negative binomial count regression models to describe bat foraging behavior relative to forest edges, stand types, and prey availability. Although some species showed affinities for certain stand types and prey items, bat activity patterns were most strongly related to forest edges. Edges were used extensively by 6 aerial-hunting bat species, but avoided by Myotis species. Forest edges function similarly to natural forest gaps, by providing foraging opportunities for aerial-hunting bat species. Therefore, the maintenance of forest edges in managed pine landscapes may enhance foraging habitat for aerial-hunting bat species. 相似文献
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Sean Sloan 《Biotropica》2007,39(4):443-446