Environmental Effect of Major Project: Object-Oriented Information Extraction and Schedule-Oriented Monitoring

With the increase of human activities, ecological security has become a hot topic across the globe. Now the status of ecological security has been influenced by the disturbance of human activities. Since 1990s, there has been many major projects built in China, such as Qinghai-Tibet Railway, the West-East gas transmission, South-North water transfer and the Three Gorges Dam in China. These projects can bring benefits in regional economic development, and affect ecological environment and ecological security. These effects can also influence operation of project security. One of the important issues is to find a balance between the two points for the smooth running of various major projects.


Introduction
With the increase of human activities, ecological security has become a hot topic across the globe. Now the status of ecological security has been influenced by the disturbance of human activities. Since 1990s, there has been many major projects built in China, such as Qinghai-Tibet Railway, the West-East gas transmission, South-North water transfer and the Three Gorges Dam in China. These projects can bring benefits in regional economic development, and affect ecological environment and ecological security. These effects can also influence operation of project security. One of the important issues is to find a balance between the two points for the smooth running of various major projects.
The focus of this article is ecological environment of major project in Beijing. It is dynamically monitored through the change of main project and ancillary project. A method is put forward to integrate multi-source data and information to collaborative analyse. It ensures the continuity of monitoring. During dynamic monitoring of construction, an advanced object-oriented information extraction of remote sensing technology combined with manual visual interpretation to achieve the extraction of target. This method can establish training data set and interpret knowledge database according to the type, spectrum, geometric and texture characteristic of different project type. Meanwhile, the sevaluation indicator system of different periods according to environmental impact assessment requirements needs to be established. Finally, we use the change detection technique to achieve the monitoring and evaluation of process-oriented of project.

Theory and implementation 2.1 Research framework
It mainly includes 3 steps in the object-oriented recognition of major projects by remote sensing images: remote sensing information modeling in high-resolution image, object-

Technical route
On the basis of the analysis of the engineering character and the characteristics in the remote sensing images(shape, texture, spectrum), we should combine the actual situations of the major project, choose the right data source, and establish the parameters of the project's construction schedule and indicator system of its surrounding ecological environment; according to those related parameters, the project's characteristics are combined in order to analyse and establish the interpret knowledge database of a project's schedule; and on the support of the database, using the technique of object-oriented to automatic extract the information of characteristic of project schedule and the ecological environment surrounded by project. By combining artificial visual interpretation to modify the extraction results, and through the analysis of the extraction information and the calculation of the monitor index, the project's construction schedule and impact of surrounding ecological environment with semiautomatic and automatic can be monitored finally. Flow Chart of Major Project by Remote Sensing Monitoring is shown in figure 2:

Ecological environment affected by major project and monitoring strategy of remote sensing
Currently, ecological damage caused by major projects of urban construction has been one of the main reasons of environmental degradation, and trends to serious. But the environmental damage and pollution causes mainly non-polluted ecological environmental impact, which is generally destruction of vegetation, destruction of partly landscape, soil erosion, impact of natural resources (land, grasslands, forests, wildlife, etc.), impact of landscape and the impact of interesting areas and so on(nature reserve, monuments, water conservation etc). Major construction projects include: point (sations, terminals and airports), polyline (Lines, pipelines and routes) and polygon (sadium area and project area). No matter which type of project, its object includes two types: the main project and ancillary project. Main project is the construction object of the project in accordance with project planning, Such as the Beijing South Railway Station main building, etc; Ancillary project means engineering facilities which plan in order to improve or supplement the principal design features and construction, such as the station square, bus station, road and etc. Its major impact on the ecological environment refers to the problems arising by cnstruction of access roads and camps. Therefore, during the schedule of construction, it is necessary to not only consider the influence to the ecological environment by the main project, but also consider the adverse effects on the surrounding environment by the ancillary project. As a result, engineering sidewalk alignment should avoid living areas as possible, sewage discharged into the sewage tank, and sidewalk trees and grass in order to greening, although it can increase the investment, it improves the construction environment.
The life cycle of major project construction mainly includes 4 stages: investigation, design, construction and operation. They are completely different periods of stage. So it should be monitoring and evaluation by stage, and discussing the impact on the ecological environment in various stages of the life cycle. Then the method of monitoring and evaluation content is then put forward. During the monitoring and evaluation, In addition to focusing on the eco-environmental impact, analysis should focus on the direct impact of the construction period and the corresponding environmental protection measures. At the same time, some aspects of design are ignored, such as the choice of site, line selection) and the management of the operation period. In particular, the land use regeneration after project construction cannot be ignored.

Investigation stage
Surrounding eco-environmental monitoring of investigation stage mainly include the environmental impact of ecological sensitive areas (nature Reserve, Scenic Area and wetlands etc), engineering spoil area and the topographic gradient of project along etc.
During the feasibility study of the investigation stage, environmental protection department should make environmental impact report. This can be confirmed through the key point of environmental protection and measures during various design stages, and make the appropriate engineering design.
For the main project, alignment should avoid the nature reserve, scenic area and wetlands etc. And it should collect local landscape characteristic and the planning information of the region.

Design stage
The design of the route should be according to the characteristics of project and the environmental geological condition of the project then take appropriate measures for ecological and environmental protection in order to prevent new pollution and ecological destruction, and protect resources and natural environment that human beings depend on.
For the main project, construction of spoil field must consider the ecological characteristic of the region, take appropriate and effective protective measure, and prevent further soil erosion. In ecological vulnerable region, major projects must follow the principle that avoid as possible, the construction site, sandstone yard must be considered repeatedly, in order to damage the vegetables as little as possible.

Construction stage
Major project during the construction stage is more complex and difficult. There are many issues to be considered; above all eco-environmental protection. The ecological environment affected by construction of major project is multifaceted, such as land resources and water pollution, chang of flora and fauna community and important impact on the ecosystem.

Operation stage
Ecological environment in operation stage of project mainly include 2 parts: Positive effects and negative effects.

Positive effect
The project has 2 main positive effects. On the one hand, the temporary construction area will be planting grass and tree for ecological restoration or rehabilitation after the construction. On the other hand, project construction department will implement a comprehensive virescence project according to design specifications and requirements.

Negative effect
The project has 2 main negative effects too. On the one hand, the facilities and activity of project can change or disturb the environment of animal habitat. Because the project can changes the animal channel and activity area. On the other hand, the enterance of a lot of people and vehicles can destroy local vegetation. This effect can reduce the biodiversity community, and change the vertical structure of communities. Long-term effect, it may lead to the cessation of community succession and even retrograde succession.

Analysis of project schedule characteristic
Case of research in this article is Beijing-Tianjin Inter-city Highspeed Railway. It is a major transportation project.
Beijing-Tianjin Inter-city Highspeed Railway is a typical project of polyline, whose railway station is a typical project of point, and the surranding area of the railway station's ancillary facilities, including the railway station square, parking place, bus stop, etc, are a typical project of polygon. This kind of project is very easy to aggravate the development of geologic hazard problems, such as landslide, soil erosion, and even affect the safety of traspoting itself and the influence on the whole benefit.
Land use during construction include: permanent sites, temporary sites and unused land. Permanent land use refers to the area of roadbed, stations, bridges, tunnels and ancillary projects of transportation engineering. Temporary land refers to vehicle transport road, materials field, access roads of construction and area of construction during the period of construction. Unused land refers to the places which are being used in a certain period due to project planning, demolition, land acquisition or other construction reasons. But such land is not being used for permanent and temporary usage temporarily.

Data collection and scheduleing
According to this research needs, and the demonstrate application needs, we collect multisource remote sensing data, and the engineering relevant statistical and planning data. Through data standardization and data scheduleing technologies, we deal with the collecting remote sensing data, in order to meet the inquirement of information extraction and monitoring applications.
We choose "BJ-1" satellite remote sensing data as primary data, and other multi-source remote sensing data as auxiliary to monitor the prior period, the middle and the last period. The data acquisition is as follows: 1. BJ-1 data Considering the project's monitored phase and the small satellite launch services period, select satellite data of the project mid-and late-phase, as the following

Auxiliary data
Ancillary data provide references for the precise alignment of the different periods or different time to these satellite images, and they are benefit to train the image selection of classification schedule and verify the results, in addition, they can greatly reduce the amount of outside work, save time and money, and also very important to ensure that we can complet the project with high quality and on time.
We need to collect the necessary supporting data according to Beijing South Railway Station's construction followed by the

Data Prescheduleing
Using remote sensing geographic information system software, such as ENVI and ARCGIS, to do geometric correction and image fusion. Work steps: control point selection, correction, registration, image fusion.

Establish engineering schedule characterization of target system
In the construction schedule, we will inevitably take and split the farm land. Thus, we use these two ways to monitor the project's progress: first, through the area change of the project itself to reflect; second, through the monitor of the construction associated with the ancillary works and the surrounding land-use change to reflect.
Different time periods have diverse characteristics in remote sensing image, thus there will be different project type (main project, ancillary project), may lead to different projects exhibit the same characteristics, as they are from artificial cement structures, but, the same project type may show different characteristics, as they have different progress (different cement hardened, different stages of progress), which gave a lot of confusing interference factors to the monitor progress.
So we need to build the engineering schedule of index system, combined the extract information from remote sensing images with monitor progress project.

Before the construction
As the project land acquisition, demolition, there will be a large continuing area of unused land or land that covered with a little vegetation, at the same time, as the project officer's presence, there will be appear construction wall, simple workshops and other architectural temporary site. Although there are construction activities, but they are not the main content to be monitored.

In the construction
Main building construction area is increasing, while the relavent ancillary construction is continued to be improved, a large number of temporary construction sites appeared (referring to road transport vehicles during the construction, materials, field, basement, construction of access roads, construction sites and barracks and other accounting ground). Unused land area is reduced. At the same time, as the project fill and cut directly destroys vegetation, changing the original shape, stacking a large number of spoil, and poor terrain conditions also produce soil erosion.

After completion
The project main building is no longer increase. A large number of temporary land and unused land will be substituted by ancillary works and ecological restoration project.
In summary, the remote sensing monitor character indicators of major projects in urban construction showed in the Object-oriented information extraction technology Table 5. Beijing South Railway Station landuse classification indicators

Establishment of interpret knowledge database
Interpret knowledge generalized various remote sensing characteristic during different stages of project, these include: hue, brightness, shape, texture, and spectrum. It provides assisted support for major project schedule and extraction of surrounding ecological environment information. Extraction of major project use artificial and object-oriented methods. So interpret knowledge database has been built for these methods of information extraction.
Basic idea: We need to analyse the image characteristics from different data sources and consider the composition, structure and environment of major project, according to different characteristics of information in remote sensing image, the element's common features are studied during different time in high-resolution remote sensing image, such as geometric features, texture features, spectral information, spatial characteristics and characteristics. Then the remote sensing information database which is suitable to BJ-1, QuickBird, IKONOS and SPOT data should be constructed. The construction schedule is shown in Figure 3.

Fig. 3. Flow chart of interpret knowledge database of major project
As data source is different, the interpret knowledge database is different as well. This research is building interpret knowledge database focused on BJ-1, SPOT, QuickBird and TM data.
Interpretation marks for example shown in the following table 6.

Indicators extraction of project schedule characteristic
A remote sensing technology was used in order to extract the indicators of project schedule characteristic directly from the remote sensing image. Thus, we put forward an indicator extraction method of object-oriented project schedule and visual interpretation of artificial intervene. This method mainly uses remote sensing technology to extract the information of land-use and land-cover.
This method mainly includes two steps: 1. Monitoring indicator extraction of land-use and land-cover based on object-oriented technology. 2. Indicator extraction of major project schedule by human intervention. The key technical route is shown in Figure  In this technical route, object-oriented information extraction is the key link. The study is based on the pixel's spectrum, shape and texture characteristics within the range of engineering research, compose to a single image object with all the similar characteristics of the pixels, and then, according to each object's spectrum and spatial characteristics, classify image object of the study area, extract the surface land use/covers information of engineering research area. The information extraction method procedure is as follows.
Based on this method procedure, we choose a mature object-oriented information extraction software package to extract the surface land use/land cover information; Then, we choose a mature GIS software platform to do more artificial work, such as merging and classification, to realize the extraction of the projects' progress characterization parameter.

Software platform choice
We take Ecognition software for example. Its object-oriented classification method basically has two kinds: the most neighboring method and member function method.

The nearest method.
It is similar to the supervid classification method, and we must choose samples to do image classification.
Advantages: operation is easy and intuitive, it does not need to summarize and distinguish these all kinds of rules, and it can quickly handle class hierarchy relationship; Disadvantages: limiting the number of object information used in classification, for example, if the information is too much. It will affect the speed of classification, increase the information redundancy, and even can not use the context very well. The classification schedule is as the diagram shows. It describes the class feature through membership (also called member function). Membership function is a fuzzy expression, it is a simple method which is used to convert any characteristic value to the range of [0, 1]. Use possibility to describe the belonging degree of the object to the class. The belonging value is usually between 0 and 1, 1 as completely belong to this category, and 0 as not. The size of the belonging value depends on the category description degree of the researching object.
This subject mainly use member function method to extract 2005 and 2007 QuickBird and SPOT data's object-oriented information of Beijing south railway station; After extraction of the classification, we can extract the progress of characterization parameter in a mature GIS software platform.

Project schedule characteristic extraction of Beijing South Railway Station in 2005
The data source is Quickbird image in 2005.Project schedule characteristic extraction of Beijing South Railway Station in 2005 is mainly includes 2 parts. One is land-use/land-cover information extraction by object-oriented of project study area in 2005. The other is project schedule characteristic extraction by human intervention.

Land-use/land-cover information extraction by object-oriented of project study area in 2005
Step 1. Image segmentation The choice of split-scale size affects the size of the object to the image, named that it affects the accuracy of the information extraction. At the same time, the different split-scale can also make the different size and number of the object's polygon of the project. Through trial and error, we can obtain the appropriate division scale and its parameters of all levels, As follows: The effect of different segmentation scale is shown in figure: (a) Level1scale 10 (b) Level2 scale 20 (c) Level3 scale 50 Fig. 6. The effect of the three layers segmentation Step 2. Classification First of all,we introduce three abstract base class (lay1, lay2, lay3), using the single value in the hierarchy to define the relationship of inheritance to level1, level2 and level3 respectively, so that each class can inheritance a layer of the object.After the definition of inheritance, make the three classes associated with the three splited layers. Then extact the hierarchical information. To extact roads and water in the level3 (large scale), vegetation and building area in level2 (Mesoscale), and the vegetation will be further broken down into woodland and grassland in level1.
After lay3 inherited level3, it was associated with level3. On the base of lay3, using the length above 300 and the mean value of level3 between 100 and 200 to extract the road.Through observing the result of the classification, we found that there were non-road objects classified as road category, we use the tool "manual" provided by Ecognition to amend it.
Using the brightness which is below 50 and the standard deviation below 15 to extract water.This classification method also extract the shadow.Through trial and error, we have found tha there is no better way to completely remove the shadow. Therefore, we use the artificial intervention to remove the shadow. Through the relationshiop of opposite, make the other unclassified object extracted into other classes.
On the base of lay2, road 2 inherited the lay3's ,water 2 inherited the lay3's.On the base of the unclassied objects,using the brightness which was above 41 and the ratio of the layer2 was above 0.37 to extract the vegetation.Through the relationshiop of opposite,make the other unclassified object extracted into Built-up areas[2].
On the base of lay1, road 1 inherited lay2's, water1 inherited lay2's, vegetation 1 inherited lay2's, build-up 1 inherited lay2's. On the base of vegetation[1],using the standard deviation which was above 13.5 to extract the woodland,and through the relationship of oppsite,extracted the grassland in the land which was not woodland.
The extraction results are shown in table 11 and figure 8:

Extraction of Road Extraction of Water Extraction of Vegetation
Extraction of Woodland Step 3. Accuracy Assessment We use pre-defined area tests the classification result. It is shown in figure 9.

Progress analysis
Through the analysis and calculation with the parameters of the project, such as area, proportion and area changes from different stages, to achieve the process monitoring of the projects.

Main project
Main project land Proportion =Main project land area/All area×100% Unused land is one of the key symbols of project completion. The area of unused land is 0 in 2005, pre-project stage; the area of temporary land is 0.0632 km2, 0.3% of total research area in May, 2007. There are not temporary lands in deadline of project. It symbolizes the project completion.

Accuracy verification
Accuracy verification mainly consists of the determination of investigation mission, research method, accuracy assessment method and the revision of result.

Determination of the investigation mission
Obtaining samples are needed for building the interpretation marks of BJ-1 satellite.
Make sure that the accuracy and the precision of assessment classification for the construction condition patch of the transportation project. It includes design of field surveyed route, determination of field sampling points, determination of indefinite patch, validity, type, location of the definite and variable patchs. They add the missing patch which are monitored by remote sensing, ensuring the reliability of the remote sensing monitoring results.
The verification mainly towards the monitoring results of Beijing South Station Project's construction schedule. The finished project condition of the year 2008 is chosen to be tested in field.

Investigation methods
There are 3 forms of field investigation:checking with maps、consulting and field verification. It begins with checking the information of variable patchs、index elements according to the map of present condition of land utilization and some other auxilliary materials; it requires consulting for patchs which are hard to ascertain; finally, the field verification is used for those indefinite patchs.
According to the monitoring results, both typical and indefinite areas of the project's schedule representative indices are chosen to set the sampling points. Finally, we get 17 sampling points. There are 2 main part of the project's verified points; 6 accessory project's verified points; 3 roads verified points; 1 grassland verified point; 3 construction land verified points. Field verified points cover the regions around.
In the schedule of implementing, each observation points should be located accurately by GPS, the project's construction progress、the start time、the state of landuse and other general materials should be recorded, digital camera is used to take at least 2~4 photos from each directions for different routes. According to the information collection results of different project's construction points, they are compared with the interpretive results and then verifying the accuracy of the extracted information in the important project areas and their surroundings.

The results of investigation
According to the record of sampling points' general materials in different project construction land, their distribution and schedule conditions are to be realized.
It is via field investigation to verify the accuracy of transportation projects' interpretive work. Both setting sampling points by GPS and recording their landuse types are necessary. And then they are compared with the interpretive results. The ratios of right ones and whole sampling points are exactly the verified accuracy results. The GPS and searial numbers are marked in the field verified map; the latter is ranked in the time sequence of verified routes.
The field relative recorded materials of Beijing South Station project are compared with the interpretive results, and then it comes to the accuracy assessment of Olympic venues' construction results.
The relative recorded materials through field investigation are compared with the interpretive results; the ratio of landuse typys which are consistent with the interpretive ones and whole sampling points is exactly the verified accuracy result. It is 74.19%.

Revised results
The field relative recorded materials of Beijing South Station project are compared with the interpretive results, and then it comes to the accuracy assessment of Olympic venues' construction results.
The interpretive results are revised by field verified report. The Specific schedulees are shown in the figure 16.

Summary
Evaluation of ecosystem has always been debated since last 60s. As a multiple system with nature, society, and economy, ecosystem impacted by multiple factors shows its complexity and nondeterminacy. This will bring a plenty of problems when we evaluate ecosystem comprehensively.
1. Among previous researches of ecosystem, the boundary between evaluation of environment assessment and ecosystem assessment was obscured, or mechanically combination of methods of different types in different ranges with different theoretical foundations is named as Eco environment method, which makes it difficult to improve and develop the eco environment method. To some degree, the credibility of ecological environment evaluation is decreased, which affects the conduct of sustainable development strategy. 2. Index systems of evaluating ecosystem should be perfected, and different scales of evaluation unit should be in different systems. Evaluation of ecosystem cannot exist without index system. In researches which are in different situations or inducted by different researchers, distribution of weight are in a large range, therefore this will lead to different results of evaluation.