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131.
Dispersal and persistence of genetically modified oilseed rape around Japanese harbors 总被引:1,自引:1,他引:0
Masaharu Kawata Kikuko Murakami Toyohisa Ishikawa 《Environmental science and pollution research international》2009,16(2):120-126
Background, aim, and scope
The possibility of gene transfer from genetically modified oilseed rape (OSR) to its cultivated or wild relatives is of concern since its commercial cultivation, because of its potential weediness and impact on the environment. Introgression of modified genes can affect conservation of agricultural crops, because there are many cultivars and wild Brassicaceae that may cross with genetically modified OSR (Brassica napus) in Japan. Japan imports more than 2 million tons of OSR a year from Canada and other countries. Since volunteers of GM OSR were found around harbors in 2004, a lot of feral GM OSR was discovered in Japan. To consider the way how to keep domestic Brassicaceae from GM contamination, we surveyed and analyzed the dispersal and persistence of GM OSR around Japanese harbors. We present the cause and abundance of GM OSR in Japan by this paper.Materials and methods
Survey of the feral OSR was performed several times a year at different seasons when domestic OSR either grows or does not around port areas. Detection of herbicide tolerance in feral B. napus was done by test papers that cross react with the modified gene product. Two kinds of herbicide tolerance (glyphosate and glufosinate) were tested.Results
The feral B. napus were discovered around all 13 harbors that import rapeseeds from foreign countries. Genetically modified, herbicide-tolerant OSR were frequently found in the surveyed populations. Two kinds of herbicide-tolerant OSR (glyphosate- and glufosinate-tolerant) were discovered in a natural condition 40 km from port to an oil factory where 60,000 tons of OSR seed are processed a year. The cause of voluntary growth of OSR is seed spillage during transportation by trucks from harbors to oil factories and other processing facilities. Some of the feral OSR growing along the roadsides of transport paths exhibited perennial growth spilling their seeds around the places. Alteration of the generation of feral GM OSR was discovered for the first time in Japan as a result of this study. We studied the yearly change of feral OSR abundances focusing on Yokkaichi port over the 4 years since 2004. The rate of GM OSR increases year to year, and reaches nearly 90% in 2008.Discussion
The possibility and consequences of gene transfer from the genetically modified OSR to domestic species (B. rapa and B. juncea) were discussed in relation to impact on domestic agriculture and on environments. Evolutional meaning of the gene transfer was also discussed with respect to the gene construct of GM OSR. This study shows the importance of another pathway of modified gene transfer to non-GM relative species by seed transportation in addition to pollen transfer from commercial cultivation of genetically modified OSR.Conclusions and recommendations
We identified unintended dispersal and persistence of GM OSR around Japanese harbors that import OSR from Canada and other countries. Both glyphosate- and glufosinate-tolerant feral B. napus were discovered. The cause of volunteer OSR is spillage of the seeds during transportation by truck to oil factory. The feral GM OSR sometimes showed perennial growth in Japanese phonological conditions which are not observed for domestic Brassicaceae. In addition, we confirmed an alteration of generations by feral GM OSR in Japan. The possibility of cross pollination and GM gene introgression to domestic varieties can occur in these environments. To improve the situation, each responsible organization, company, administration, or government should establish measures how to stop the dispersal and persistence of GM OSR in nature. Also, the GM plant developers are responsible for revising this situation. 相似文献132.
Nathalie Colbach 《Environmental science and pollution research international》2009,16(3):348-360
133.
The digital workshop: exploring the use of interactive and immersive visualisation tools in participatory planning 总被引:1,自引:0,他引:1
Salter JD Campbell C Journeay M Sheppard SR 《Journal of environmental management》2009,90(6):2090-2101
This paper examines the emerging role of digital tools in a collaborative planning process for British Columbia's Bowen Island. The goal of this research was to evaluate the effectiveness of a 'digital workshop', combining the interactive CommunityViz tool with the immersive lab facilities at the Collaborative for Advanced Landscape Planning (CALP). In support of the larger community planning process, two 3-h workshops were held at CALP's Landscape Immersion Lab. To facilitate collaborative exploration, the interactive landscape visualisation and real-time data analysis capabilities of CommunityViz were employed to illustrate the possible outcomes of residential density policies for Bowen Island's Snug Cove community. The community planning workshops were structured to provide the 14 semi-expert participants with the opportunity to explore and discuss the contentious residential density components of the draft Snug Cove Village Plan. The abilities to dynamically explore the visualisations of the planning proposals, and to see real-time changes in indicator metrics were considered particularly informative, and appeared to increase participants' understanding of the plan. Written and verbal responses indicated, however, that there was insufficient time to examine and interact with the information during the workshop, suggesting a need to examine in greater depth how and when these tools might best be employed in collaborative settings. Current and future research relating to this project is discussed. 相似文献
134.
Sand-trapping fences modify the character of the coastal landscape and change its spatial structure, image, and meaning. This
paper examines the relationship between these changes and fence usage at the municipal level, where most decisions about fence
deployment are made. Use of fences in 29 municipalities on the developed coast of New Jersey is examined over a 6-year period.
Interviews with municipal officers indicate that wooden slat sand-trapping fences are used primarily to build dunes to provide
protection against wave uprush and flooding, but they are also used to control pedestrian traffic and demarcate territory.
These uses result in changes in landforms and habitats. An aerial video inventory of fences taken in 2002 indicates that 82%
of the shoreline had fences and 72% had dunes. Single and double straight fence rows are the most commonly used. Fences are
often built to accomplish a specific primary purpose, but they can cause many different and often unanticipated changes to
the landscape. The effects of a sand fence change through time as the initial structure traps sand, creates a dune that is
colonized by vegetation, and becomes integrated into the environment by increasing topographic variability and aesthetic and
habitat value. Sand fences can be made more compatible with natural processes by not placing them in locations where sources
of wind blown sand are restricted or in unnatural shore perpendicular orientations. Symbolic fences are less expensive, are
easy to replace when damaged, are less visually intrusive, and can be used for controlling pedestrian access. 相似文献
135.
Ecologists are beginning to recognize the effect of heterogeneity on structure and function in arid and semiarid ecosystems.
Additionally, the influences of temperature on ecosystems are widely documented, but landscape temperature patterns and relationships
with vegetation are rarely reported in ecological studies. To better understand the importance of temperature patterns to
the conservation and restoration of native ecosystems, we designed an experiment to investigate relationships among soil surface
temperature, landscape heterogeneity, and grazing intensity. Grazing intensity did influence the vegetation structure and
composition. Heavy treatments had the greatest bare ground and the least vertical structure. Ungrazed treatments had the most
litter and live grass cover. However, average temperatures among the three grazing treatments were not different and ranged
less than 2°C during midday summer periods. The temperature difference between riparian and upland landscapes within grazing
treatments was 21°C. Landscape position (riparian vs. upland) did have a significant influence on soil surface temperature
and produced a variation in temperature 11 times greater than grazing intensities. Thermal heterogeneity did not differ among
grazing treatments. Lower soil surface temperatures (associated with riparian areas) may provide a critical thermal refuge
for many animals in arid and semiarid ecosystems on hot summer days, when air temperatures can exceed 37°C. Riparian zones,
specifically riparian vegetation, are an important component in ecosystem management. 相似文献
136.
Mehrey G. Vaghti Marcel Holyoak Amy Williams Theresa S. Talley Alexander K. Fremier Steven E. Greco 《Environmental management》2009,43(1):28-37
Societal constraints often limit full process restoration in large river systems, making local rehabilitation activities valuable
for regeneration of riparian vegetation. A target of much mitigation and restoration is the federally threatened Valley elderberry
longhorn beetle and its sole host plant, blue elderberry, in upper riparian floodplain environments. However, blue elderberry
ecology is not well understood and restoration attempts typically have low success rates. We determined broad-scale habitat
characteristics of elderberry in altered systems and examined associated plant species composition in remnant habitat. We
quantified vegetation community composition in 139 remnant riparian forest patches along the Sacramento River and elderberry
stem diameters along this and four adjacent rivers. The greatest proportion of plots containing elderberry was located on
higher and older floodplain surfaces and in riparian woodlands dominated by black walnut. Blue elderberry saplings and shrubs
with stems <5.0 cm in diameter were rare, suggesting a lack of recruitment. A complex suite of vegetation was associated with
blue elderberry, including several invasive species which are potentially outcompeting seedlings for light, water, or other
resources. Such lack of recruitment places increased importance on horticultural restoration for the survival of an imperiled
species. These findings further indicate a need to ascertain whether intervention is necessary to maintain functional and
diverse riparian woodlands, and a need to monitor vegetative species composition over time, especially in relation to flow
regulation. 相似文献
137.
Conservation and protection of soil and water resources and visual aspects of landscape, as well as the promotion of biodiversity, are some of the central tasks of environmental policy development and social politics in the future. One of the main questions is: ‘which agricultural systems are able to guarantee sustained resource-conserving land use?’ Based on the ecological risk concepts of the 1970s and 1980s, a potential impact model was developed using a universal assessment algorithm derived from fuzzy logic. The model estimated the potential impact of agricultural land use on ecosystem function using a few resource indicators. Intervention intensities of agricultural land-use are set in relation to site conditions and aggregated for each of several defined potential impact categories. The interpretation with respect to risk and the calculation of potential impact values are explained. 相似文献
138.
Assessment of the contribution of land use pattern and intensity to landscape quality: use of a landscape indicator 总被引:4,自引:0,他引:4
The objective of this research work is the evaluation of the impact of landuse pattern and intensity on landscape by means of an indicator. The method used to calculate a ‘landscape indicator’ (Iland) allows to take into account the objective as well as the subjective approach of landscape. Iland corresponds to the degree of agreement between landscape supply by farmers and landscape demand by the social groups. The supply and the demand are evaluated through four criteria: ‘diversity’, ‘upkeep’, ‘openness’ and ‘heritage’. The landscape supply is calculated from data of landscape objects (punctual, linear and spatial) for each criterion recorded at the field level. The values of the four criteria for the landscape demand are allocated by the user(s) of the indicator (decision makers, regional council, social groups…) into five classes (0–4). The value of the landscape indicator is the least favourable difference between supply and demand for the four criteria. An example of calculation of the ‘landscape indicator’ for an arable farm is given. The collection of data needs 2 h with the farmer and 2 h for a survey of the farm land. 相似文献
139.
Recognition and understanding of landscape dynamics as a historical legacy of disturbances are necessary for sustainable management
of forest ecosystems. This study analyzed spatial and temporal changes in land use and land cover patterns in a typical mountain
watershed in the Gumushane district along the Northeastern part of Turkey. The area is investigated by comparing LANDSAT images
from 1987 to 2000 and evaluated the temporal changes of spatial structure of forest conditions through spatial analysis of
forest cover type maps from 1971 and 1987 using GIS and FRAGSTATS™.
The results show a general decreasing trend in area of natural land cover types including broadleaf and conifer forests as
well as coppice between 1971 and 1987 (0.54%, respectively). In contrast, between 1987 and 2000 this natural land cover types
show increasing trend (1.6%). In parallel with forest dynamics, the area of managed land including lowland and upland agricultural
areas, rangelands and grasslands increased during the first period and decreased during second period. In terms of spatial
configuration, Gümüşhane forests aren’t generally fragmented by intensive forest utilization in the latter periods. This is
partially due to out-migration of rural population in Gümüşhane. Nevertheless, land use pattern significantly changed over
time depending on a few factors such as unregulated management actions, social pressure and demographic movements. The study
revealed that demographic movements have a major effect on landscape dynamics. 相似文献
140.
Approaches to integrating indicators into 3D landscape visualisations and their benefits for participative planning situations 总被引:1,自引:0,他引:1
In discussing issues of landscape change, the complex relationships in the landscape have to be assessed. In participative planning processes, 3D visualisations have a high potential as an aid in understanding and communicating characteristics of landscape conditions by integrating visual and non-visual landscape information. Unclear is, which design and how much interactivity is required for an indicator visualisation that would suit stakeholders best in workshop situations. This paper describes the preparation and application of three different types of integrated 3D visualisations in workshops conducted in the Entlebuch UNESCO Biosphere Reserve (CH). The results reveal that simple representations of a complex issue created by draping thematic maps on the 3D model can make problematic developments visible at a glance; that diagrams linked to the spatial context can help draw attention to problematic relationships not considered beforehand; and that the size of species as indicators of conditions of the landscape's production and biotope function seems to provide a common language for stakeholders with different perspectives. Overall, the of the indicators the functions required to assist in information processing. Further research should focus on testing the effectiveness of the integrated visualisation tools in participative processes for the general public. 相似文献