The objectives of Integrated Ecosystem Assessment for Western Development of China includes: (1) providing scientific basis for ecosystem protection, ecosystem management and ecological construction in the western development; (2) developing complete database and analytical tools and strengthening decision-making support capacity; and (3) improving ecosystem management in China, spreading ecological knowledge to the public, serving decision-making of local and central governments, and promoting socio-economic sustainable development. The design and implementation of the project are of significance under the macro background of western development of China. By the integrated assessment of western China, we can get the first-hand data covering all the environmental factors as well as disclose the situations and their changing trends of ecosystem in the western part of China, which will benefit the decision-making for the central and local governments in the implementation of the western development strategy. In other words, the implementation of the project, to a certain extent, can guarantee the regional sustainable development of western China.
The Tibetan Plateau (Qinghai-Xizang Plateau) is a unique biogeographic region in the world, where various landscapes, altitudinal belts, alpine ecosystems, and endangered and endemic species have been developed. A total of 26 altitudinal belts, 28 spectra of altitudinal belts, 12,000 species of vascular plant, 5,000 species of epiphytes, 210 species of mammals, and 532 species of birds have been recorded. The plateau is also one of the centers of species formation and differentiation in the world. To protect the biodiversity of the plateau, about 80 nature reserves have been designated, of which 45 are national or provincial, covering about 22% of the plateau area. Most of the nature reserves are distributed in the southeastern plateau. Recently, the Chinese government has initiated the “Natural Forests Protection Project of China,” mainly in the upper reaches of the Yangtze and Yellow rivers. “No logging” policies have been made and implemented for these areas.
The karst landforms distributed on the Qinghai-Xizang (Tibet) Plateau can be genetically classed with the Tertiary underground karst, which were gradually exhumed to the surface with the uplift of the plateau during Quaternary period. The relative deposits of the Tertiary palaeokarst processes, such as the residuum and speleothem, were discovered recently in the southern and southeastern fringe areas of the plateau, where has geological-currently been disintegrated by the headward erosion processes of the modern river systems. The major chemical components of the clay portion of the residuum consist mainly of SiO2C, Al2CO3 and Fe2O3. The clay minerals composition of the clay portion belongs to illite-kaolinite pattern for most of the residuum samples, and kaolinite-illite pattern for a few of the samples. It can be judged from the silicic acid index and the clay minerals composition that the formation of the residuum of the Plateau was in its initial phase. However, such a lower chemical weathering index only reflected the weathering degree in the bottom or lower parts of the lateritic weathering crust. The relatively intensive chemical weathering processes of the surface layers of the lateritic weathering crust could be logically speculated. The surface feature textures of quartz grains in the residuum were formed mainly by the chemical erosion, which revealed a long-term humid-tropical environment when the residuum and the palaeokarst formed.
Based on the results of remote sensing investigations of the landscapes of 1995 and 2000, the national distribution of sandy desertified land and its interaction with other landscapes are classified, and five zonal types are distinguished. The data of nationally distributed 400 meteorological stations of 1999 are processed. With the GIS method, the data are spatially interpolated, and the national database of wind field concerned with wind erosion is established. In arid and semi-arid areas of China, the intensity of wind field is one of the key factors that controls the development of landscape especially in desert and its adjacent area. Different indexes are set up to describe the intensity of wind field, the method suggested by the wind erosion prediction models of RWEQ is also adopted to express the intensity of wind. The Weibull distribution is used to describe the wind field in China. Based on the analysis of the process of the wind erosion-driven landscape changes, this article proposes and discusses the control measures of wind erosion.
With the development of Internet technologies, Internet Based Information System (IBIS) arises with more advantages: Firstly, it is convenient for users to use owing to the introduction of Internet technologies. Secondly, it benefits greatly the data dissemination and data sharing based on Internet. The most important but not the last is that we can establish the information service network supported by its technologies and the facilities of information highway. So, it would be significant to design IBIS to realize the data collection, sharing and dissemination on Internet. There are many factors affecting regional environment. So it is not easy to realize the integrated environmental monitoring. Given this, we designed the Internet based environmental monitoring information system. By the virtue of the Internet based environmental monitoring information system, the management and storage of environmental monitoring data would be easier, which lays the foundation to actualize the environmental monitoring efficiently.
The development and distribution pattern of rural settlements was greatly limited by their natural and social environment. Taking Yulin prefecture in northern Shaanxi’s Loess Plateau area as an example, 1:250,000 map-scale national geographical database as a major information source, a GIS-based research was conducted to investigate the spatial distribution of the rural settlements. In this paper, many significant characteristics of the rural settlement distribution are reviewed by means of a series of GIS-based information processing methodology. The results obtained in this study should be helpful for the urban and rural settlements reconstruction planning in this area.
Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rim’s sustainable development. Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.
The models for landscape connectivity are distinguished into models for line connectivity, vertex connectivity, network connectivity and patch connectivity separately. Because the models for line connectivity, for vertex connectivity, and for network connectivity have long been studied and have become ripe, the model for patch connectivity is paid special attention in this paper. The patch connectivity is defined as the average movement efficiency (minimizing movement distance) of animal migrants or plant propagules in patches of a region under consideration. According to this definition, a model for landscape connectivity is mathematically deduced to apply to GIS data. The application of model for patch connectivity in the new-born wetland of the Yellow River Delta shows patch connectivity has a negative interrelation with human impact intensity and landscape diversity.
The loess mounds are a newly discovered type of landforms on the Laizhou Bay plain south of the Bohai Sea. Research shows that they were formed in the late period of the late Pleistocene when the Bohai Sea was exposed in the period of late Wümu glacial age and changed into plain. As the exposed area is not protected by vegetation, the sediments at the sea bottom are blown and transported southward by strong north winds, and deposit on the coastal plains. As thick loess is accumulated, the loess mound landforms are formed in the direction of down wind.
Western North Pacific Subtropical High is a very important atmospheric circulation system influencing the summer climate over eastern China. Its interdecadal change is analyzed in this study. There is a significant decadal shift in about 1979/1980. Since 1980, the Western North Pacific Subtropical High has enlarged, intensified, and shifted southwestward. This change gives rise to an anti-cyclonic circulation anomaly over the region from the South China Sea to western Pacific and thus causes wet anomalies over the Yangtze River valley. During the summers of 1980-1999, the precipitation is 63.9 mm above normal, while during 1958-1979 it is 27.3 mm below normal. The difference is significant at the 99% confidence level as a t-test shown. The southwestward expanding of the Western North Pacific Subtropical High also leads to a significant warming in southern China, during 1980-1999 the summer mean temperature is 0.37oC warmer than that of the period 1958-1979. The strong warming is primarily due to the clearer skies associated with the stronger downward air motion as the Western North Pacific Subtropical High expanding to the west and controlling southern China. It is also found that the relative percentage of tropical cyclones in the regions south of 20oN is decreasing since the 1980s, but in the regions north of 20oN that is increasing at the same time. The Western North Pacific Subtropical High responds significantly to sea surface temperature of the tropical eastern Pacific with a lag of one-two seasons and simultaneously to sea surface temperature of the tropical Indian Ocean. The changes in the sea surface temperatures are mainly responsible for the interdecadal variability of the Western North Pacific Subtropical High.
Based on the mean yearly precipitation and the total yearly evaporation data of 295 meteorological stations in China in 1951-1999, the aridity index is calculated in this paper. According to the aridity index, the climatic regions in China are classified into three types, namely, arid region, semi-arid region and humid region. Dry and wet climate boundaries in China fluctuate markedly and differentiate greatly in each region in the past 50 years. The fluctuation amplitudes are 20-400 km in Northeast China, 40-400 km in North China, 30-350 km in the eastern part of Northwest China and 40-370 km in Southwest China. Before the 1980s (including 1980), the climate tended to be dry in Northeast China and North China, to be wet in the eastern part of Northwest China and very wet in Southwest China. Since the 1990s there have been dry signs in Southwest China, the eastern part of Northwest China and North China. The climate becomes wetter in Northeast China. Semi-arid region is the transitional zone between humid and arid regions, the monsoon edge belt in China, and the susceptible region of environmental evolution. At the end of the 1960s dry and wet climate in China witnessed abrupt changes, changing wetness into dryness. Dry and wet climate boundaries show the fluctuation characteristics of the whole shifts and the opposite fluctuations of eastward, westward, southward and northward directions. The fluctuations of climatic boundaries and the dry and wet variations of climate have distinctive interdecadal features.
The groundwater table has been declining at a rate of 0.65 m/yr in Luancheng County since large scale groundwater extraction carried out in the 1960s. The drop of precipitation, substantial increase in agricultural output, variations of crop planting structure and construction of water conservancy projects in the headwater area all tie up with the decline of the groundwater table. On the basis of analyzing the hydrogeological conditions and the water resources utilization of Luancheng County, a three-dimensional groundwater flow model was developed to simulate the county’s groundwater flow through finite-difference method using Visual Modflow software. We divide the research field into four parts after analyzing the hydrogeological condition. Based on parameter calibration and adjustment using measured data, the hydraulic conductivity and specific yield were simulated. Using the calibrated model, we analyze the agricultural water saving potentiality and its influence on the groundwater. The results are as follows: (1) if we decrease the amount of water extracted by 0.14×108 m3, the average groundwater table of the five observation wells in December will rise by 0.33 m; (2) if we decrease the water by 0.29× 108 m3, the average groundwater table of the five observation wells in December will rise by 0.64 m; and (3) if we increase the water by 0.29×108 m3, the average groundwater table of the five observation wells in December will decline by 0.45 m. So we can draw a conclusion that controlling the agricultural water use is an important way to prevent the decline of groundwater table.
Through the study of mutual process between groundwater systems and eco-environmental water demand, the eco-environmental water demand is brought into groundwater systems model as the important water consumption item and unification of groundwater’s economic, environmental and ecological functions were taken into account. Based on eco-environmental water demand at Da’an in Jilin province, a three-dimensional simulation and optimized management model of groundwater systems was established. All water balance components of groundwater systems in 1998 and 1999 were simulated with this model and the best optimal exploitation scheme of groundwater systems in 2000 was determined, so that groundwater resource was efficiently utilized and good economic, ecologic and social benefits were obtained.
Clearing up sediment and regolith on the foundation of the dam in the Three Gorges of the Yangtze River in 1999, riverbed were exposed. On the basis of weathering granite regolith sampled from different portions of the valley landforms, by analysing total chemical contents with X rays fluorescent slice and calculating proper value of chemical element transferring ratio and intensity, the transferring law of chemical elements in different portions of the landforms were concluded: 1) In various landforms of the river valley, the process of desilication is not distinct; 2) in weathering granite regolith of riverbed, easy soluble CaO and MgO are relatively enriched whereas Al2O3 tends to decrease. The enriching rate of Fe2O3 is the greatest in various landforms of the river valley; 3) in weathering granite regolith of flood-plain, K2O and MgO contents are relatively enriched; 4) the weathering granite regolith of valley slope is a typical north subtropical weathering regolith, and its chemical weathering degree is in the transition phase from early to middle period; and 5) there is an opposite layer where K2O is relatively leaching and Na2O relatively enriching in 6.5 m depth of all weathering granite regolith.
Soil degradation, defined as lowering and losing of soil functions, is becoming more and more serious worldwide in recent decades, and poses a threat to agricultural production and terrestrial ecosystem. It is estimated that nearly 2 billion ha of soil resources in the world have been degraded, namely approximately 22% of the total cropland, pasture, forest, and woodland. Globally, soil erosion, chemical deterioration and physical degradation are the important parts amongst various types of soil degradation. As a natural process, soil degradation can be enhanced or dampened by a variety of human activities such as inappropriate agricultural management, overgrazing, deforestation, etc. Degraded soil means less food. As a result of soil degradation, it is estimated that about 11.9-13.4% of the global agricultural supply has been lost in the past five decades. Besides, soil degradation is also associated with off-site problems of sedimentation, climate change, watershed functions, and changes in natural habitats leading to loss of genetic stock and biodiversity. Therefore, it is essential to combat soil degradation at different levels and scales worldwide, not only for food security and ecological health, but also for the guarantee of global sustainable development.