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1.
Identification of Forest Vegetation Using Vegetation Indices   总被引:1,自引:0,他引:1  
Spectral feature of forest vegetation with remote sensing techniques is the research topic all over the world, because forest plays an important role in human beings' living environment. Research on vegetation classification with vegetation index is still very little recently. This paper proposes a method of identifying forest types based on vegetation indices, because the contrast of absorbing red waveband with reflecting near-infrared waveband strongly for different vegetation types is recognized as the theoretic basis of vegetation analysis with remote sensing. Vegetation index is highly related to leaf area index, absorbed photosynthetically active radiation and vegetation cover. Vegetation index reflects photosynthesis intensity of plants and manifests different forest types. According to reflectance data of forest canopy and soil line equation NIR=1.506R+0.0076 in Jingyuetan, Changchun of China, many vegetation indices are calculated and analyzed. The result shows that the relationships between veg  相似文献   

2.
Evaluating the biodiversity of previous and current species in a forest community is an important task. Some methodological researches and effective applications have been carried out widely in the temperate upland zone. However, they lack related researches in coastal shelter forests. This paper attempts to analyze them for Jiaonan coastal forest communities from the following three aspects, the relationship between plant biodiversity structure and its environment, the nexus between biodivers…  相似文献   

3.
Carbon labels are innovative medium and tools for climate change communication and low-carbon marketing. This study aims at examining how college students are aware of low-carbon and carbon labels, whether they are more willing to communicate low-carbon ideas, and also the determinants affecting their interpersonal communication of carbon labels. The multiple regression analysis shows that Chinese college students’ willingness of interpersonal communication of carbon labels are significantly influenced by their awareness of climate change crisis, the perceived value of carbon labels, the consideration of product environmental attributes, the preferences of carbon labels, the household background, and their educational background. In response to these factors, this paper proposes, in a public perspective, the strategies to enhance the dissemination of carbon labels.  相似文献   

4.
Environment, Development and Sustainability - Although sustainability assessment is widely discussed at Brazil, in Brazilian Amazon its use is still little applied, considering this territory is...  相似文献   

5.
Ecological and phytocenotic features of forest communities were studied in the southwest of Moscow oblast. Based on the ecomorphological groups of species prevalent in the herb–dwarf shrub and moss layers, five groups of communities typical of the conifer–broadleaf forest zone were distinguished (small-herb, small herb-large herb, large-herb, moist-herb, and mixed-herb communities), and their composition was analyzed. Discriminant analysis of the species composition of lower vegetation layers revealed significant differences between the syntaxa, with the percentage of correct classification being 89.8%. To evaluate ecological determination of the above groups of communities, a hypothesis was tested concerning the correlation of their composition with ecotope properties. This hypothesis was verified by means of (1) ordination by ecological indicator values and interpretation of the axes, (2) revealing differences in ecological regimes between habitats of the syntaxa, and (3) combined analysis of on-ground and remote sensing data, particularly spectral brightness of satellite images and morphometric characteristics of the terrain surface. The results confirmed the informativeness of the syntaxa distinguished based on the species composition of the ground vegetation layer and mapping of the ecological regimes of habitats.  相似文献   

6.
With globalization, virtual exchanges of natural resources embodied in traded commodities redistribute geographically land use and its environmental impacts. Benefits of national forest protection may be undermined at the global-scale by leakage through international trade. We studied land use displacement associated with national policies to protect forests in Bhutan. This case study provides a simple situation: a dominant forest cover almost unaffected by agricultural expansion, a rural economy dominated by the primary sector, centralized forest conservation policies, and a dominant trading partner. We assessed the net effects at the international level of the Bhutanese forest protection policies by accounting for trade in wood products with India. Our results show that these policies have been effective in maintaining a high forest cover, but have been accompanied by an increasing displacement of forest use to India. In 1996–2011, the difference between the total volume of wood imported from India and the total volume exported from Bhutan—i.e., the net displacement—corresponds to 27 % of the total volume consumed in Bhutan. In 2011, 68 % of the total forest area required to produce the wood consumed in Bhutan was located in India. The wood imported by Bhutan was likely originating from tree plantations in the northeastern Indian states. Since Bhutan has few tree plantations and very valuable natural forests, the net international-level ecological impacts of this land use displacement is arguably positive. Most of the wood imports of Bhutan were wood charcoal for its emerging chemical industries. This case of displacement reflects functional upgrading in the value-chain rather than an externalization of consumption-based environmental costs. Through its government policies, Bhutan has managed to support its economic development while protecting its forests and leapfrogging the negative impacts on forests generally associated with the early stages of modernization.  相似文献   

7.
How well does the general public understand the concept of urban resilience? We address this question via an online survey of 500+ citizens living in three large Australian cities (Sydney, Melbourne and Perth). The majority of respondents claim not to know what urban resilience means. Of the remaining respondents, understanding ranges from poor to sophisticated. To circumvent this stated lack of understanding, we cast the concept of urban resilience into a more familiar framework consisting of risk and ability to cope with threats. This allows us to assess perceptions about what may challenge the resilience of Australian cities. Two concerns clearly emerge: (1) violence and social unrest and (2) environmental threats. Analysing a number of constructs from the social psychology literature reveals that these two concerns hold different cognitive signatures, whose understanding may facilitate discussion and communication within a public engagement process.  相似文献   

8.
Environment, Development and Sustainability - The human pressure on nature makes it imperative understanding how environmental issues can influence the world view of society. The aim of the current...  相似文献   

9.
Forest cover is viewed as a resource for the nation as it provides ecosystem services. However, it becomes a burden and retards development for the people of the area, particularly the hills, where such forests flourish. Enactment of stringent laws over the past few decades has strictly prohibited tree felling in these areas, and it has become a deterrent in their growth process. While on one hand, the plains are abuzz with economic activity, on the other hand, the sparse population of the hills is compelled to bear the responsibility of maintaining ecological balance. In this context, the issue of development along with forest sustainability becomes important. Using the case study of the hills of Uttarakhand, India, the paper attempts to highlight the problems and the possible strategies that may be adopted to facilitate inclusive socioeconomic development of forest dwellers while ensuring conservation and enhancement of forest cover.  相似文献   

10.
Russian Journal of Ecology - To assess carbon dioxide exchange in the ecosystem of cowberry–lichen pine forest, 8790 eddy covariance measurements were made during the summer–autumn...  相似文献   

11.

In tropical areas, pioneer occupation fronts steer the rapid expansion of deforestation, contributing to carbon emissions. Up-to-date carbon emission estimates covering the long-term development of such frontiers depend on the availability of high spatial–temporal resolution data. In this paper, we provide a detailed assessment of carbon losses from deforestation and potential forest degradation from fragmentation for one expanding frontier in the Brazilian Amazon. We focused on one of the Amazonia’s hot-spots of forest loss, the BR-163 highway that connects the high productivity agricultural landscapes in Mato Grosso with the exporting harbors of the Amazon. We used multi-decadal (1984–2012) Landsat-based time series on forested and non-forested area in combination with a carbon book-keeping model. We show a 36% reduction in 1984s biomass carbon stocks, which led to the emission of 611.5 TgCO2 between 1985 and 1998 (43.6 TgCO2 year−1) and 959.8 TgCO2 over 1999–2012 (68.5 TgCO2 year−1). Overall, fragmentation-related carbon losses represented 1.88% of total emissions by 2012, with an increasing relevance since 2004. We compared the Brazilian Space Agency deforestation assessment (PRODES) with our data and found that small deforestation polygons not captured by PRODES had increasing importance on estimated deforestation carbon losses since 2000. The comparative analysis improved the understanding of data-source-related uncertainties on carbon estimates and indicated disagreement areas between datasets that could be subject of future research. Furthermore, spatially explicit, annual deforestation and emission estimates like the ones derived from this study are important for setting regional baselines for REDD+ or similar payment for ecosystem services frameworks.

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12.
Since 1991, the Instituto Español de Oceanografía has monitored the concentrations of trace metals in wild mussels from the north (Cantabrian Sea) and northwest (Atlantic) coasts of Spain to define geographical distributions and temporal trends. While Cu, Zn and As concentrations presented fairly uniform geographical distributions, Hg and Pb concentrations were higher in mussels from the Cantabrian sea region as a result of historical anthropogenic activities. Cd, on the other hand, appeared to be more affected by natural processes on the northwest Atlantic coast (i.e., upwelling) than by human activity. Approximately 70% of the paired observations showed downward trends, 50% of these significant, with time. An improvement in environmental conditions along the northern coasts of Spain is evident despite that some metal levels resulted above the Background Assessment Concentrations given by OSPAR to assess potentially harmful occurrences.  相似文献   

13.
The spatial and temporal distributions of the anthropogenic radionuclides 137Cs and 90Sr, originating from nuclear bomb testing, the Sellafield reprocessing plant in the Irish Sea (UK), and from the Ob and Yenisey river discharges to the Arctic Ocean, have been simulated using the global version of the Miami Isopycnic Coordinate Ocean Model (MICOM). The physical model is forced with daily atmospheric re-analysis fields for the period of 1948–1999. Comparison of the temporal evolution of the observed and the simulated concentrations of 90Sr has been performed in the Kara Sea. The relative contributions of the different sources on the temporal and spatial distributions of the surface 90Sr are quantified over the simulated period. It follows that the Ob river discharge dominated the surface 90Sr over most of the Arctic Ocean and along the eastern and western coasts of Greenland before 1960. During the period of 1980–1990, the atmospheric fallout and the Ob river discharge were equally important for the 90Sr distribution in the Arctic Ocean. Furthermore, an attempt has been made to explore the possible dispersion of accidental released 90Sr from the Ob and Yenisey rivers under a global warming scenario (2 × CO2). The difference between the present-day and the global warming scenario runs indicates that more of the released 90Sr from the Ob and Yenisey rivers is confined to the Arctic Ocean in the global warming run, particularly in the near coastal, non-European part of the Arctic Ocean.  相似文献   

14.
Russian Journal of Ecology - The paper is aimed in ants’ preference among seeds with elaiosomes. Seeds with elaiosomes of plants Asarum europaeum, Viola arvensis, Symphytum officinale,...  相似文献   

15.
Abstract

Suburbanization in large cities is an important phenomenon in the process of urbanization development in China in recent decades, which plays a very important role in promoting city development, whereas some side effects on the eco-environment appeared at the same time. This paper, taking Xi’an City in China as a case study site, analyzed the features of population suburbanization and industry suburbanization and pointed out the impacts of suburbanization on urban eco-environment. Based on the research, suggestions of countermeasures for urban planning and municipal management of Xi’an City in protecting urban eco-environment and conserving natural ecology were put forward in the end.  相似文献   

16.
Images in children’s books can leave a more lasting impression in young learners’ minds than text. Therefore, it is important for children’s books to use images as a teaching tool, especially regarding global issues such as environmental sustainability. This study examined how the images in nonfiction children’s books approach the topic of sustainability and whether these images support the overall goals of environmental education. We selected seven easy-to-access trade books which yielded 384 images for analysis. Two coders analyzed the images according to the following categories: (a) gender and age, (b) actions of people, (c) depictions of nature, (d) depictions of objects, (e) structures, and (f) habitation. Results show that nearly half of the images (48 %) depicted non-natural objects (16 %) or humans (31 %). One half of the images portrayed humans as consumers. Gender bias was evident, with 33 % of females portrayed as consumers and only 16 % of males portrayed as consumers. Similarly, 12 % of the images with males showed them engaged in recycling behavior, while only 4 % of the images showed females recycling. Of the 32 % of images depicting nature, individual plants rather than ecosystems were portrayed. Depictions of man-made systems predominated the images, a surprising finding. No images established the connection between consumerism and the depletion of natural resources or pollution, and further sustainable actions or lifestyles were not portrayed, implying that consumption is a societal norm. We conclude with recommendations for the use of images in children’s literature focusing on environmental education and sustainability.  相似文献   

17.
Suburbanization in large cities is an important phenomenon in the process of urbanization development in China in recent decades,which plays a very important role in promoting city development,whereas some side effects on the eco-environment appeared at the same time.This paper,taking Xi’an City in China as a case study site,analyzed the features of population suburbanization and industry suburbanization and pointed out the impacts of suburbanization on urban eco-environment.Based on the research,suggestions of countermeasures for urban planning and municipal management of Xi’an City in protecting urban eco-environment and conserving natural ecology were put forward in the end.  相似文献   

18.
The species studied individually responded to different forms of mineral fertilizers introduced into the soil. Some species positively responded to the application of one nutrient (Easter-bell starwort, millet grass, and bilberry) or several nutrients (wood sorrel and hairy wood rush), whereas other species responded negatively.  相似文献   

19.
Russian Journal of Ecology - Studies in the northern forest–tundra of Siberia have been performed to estimate temperature conditions in individual months of the growing season that have an...  相似文献   

20.
We attempt to understand, scientifically, how different members of the mining concession, impacted communities, and government authorities behave when a conflicting situation arises. The main purpose of our effort is to start developing a framework for the scientific modeling of stakeholders’ behavior, and we create a reality-driven generic scenario of conflict. We assume that the managers and superintendants of a mining operation currently envision a problem; one that tests the limits of the commitment of the company’s mission statement, and of the spectrum of actions taken which are embedded in the “culture” of the company’s corporate social responsibility. It is an “event” that highlights the nature of an overall problem that the company would like to predict and act proactively: the integration of scientific tools, sustainability, and cultural realities within a mining framework. We adapt an agent-based modeling approach and start with a theoretical understanding of certain social behavior, build a model, and simulate “what if” scenarios to understand its dynamics to gain a better insight of the complexity of a seemingly simple social system of interest.  相似文献   

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