As an important part of construction land, industrial trades land intensive use has effect on the management of urban land. Evaluation of land intensive use from industrial trades was made for explaining the current state and differences between various industrial trades land intensive use, which can provide some references for establishing the control standard of industrial trades land intensive use. Some typical enterprises were measured with the questionnaire for industrial land intensive use in Jiangsu Province. We got 1020 validated from 1047 questionnaires with answering rate of 97.42%, and got some industrial enterprise information about land use behavior, input-output, personnel composing and resource consumption by questionnaire survey. We established the index system which includes land use structure, land use intensity, land use input and land use output with four sub-goals and 11 indexes, in order to evaluate the industrial trades land intensive use. An analytic hierarchy process (AHP) evaluation method based on real coding based accelerating genetic algorithm (RAGA) is integrated. The results indicate that high weight precision and global convergence can be acquired with RAGA-AHP. The industrial trades land intensive use is low as a whole in Jiangsu Province. As for various industrial trades land, the intensity of communication and electron manufacture is 76.74, the highest of all trades, while the intensity of beverage manufacture is 13.42. In the 29 industrial trades, only three trades of land use intensity, which are electronic and telecommunications equipment, rubber products and leather products are more than 60. The difference of land use intensity between industrial trades which attached to the same kinds of industry is little, while that attached to the different kinds of industry is remarkable. The land use intensity from high to low is electron industry, chemical industry, mechanical industry, metallurgy industry, weaving industry, medical industry, agricultural products rough processing. Because the differences of industry specialty, production features between the same or similar trade are not significant. Accordingly, there are similar land use structure and land use intensity. So the characteristics of industry specialty, production features between different industries are the most important reason for their diversity of land intensive use.
Moderate scale of agricultural operation is one of the most effective means to solve the "san nong" problem, narrow the gap between rural and urban areas, and safeguard national stability. On the basis of demonstrating the possibility and inevitability of the agricultural scale in Jiangsu Province, we use the nonlinear model to discuss how to realize the steady and optimum growth space of the agricultural scale economy under the premise that self-sufficient rate of grain achieve 80% in developed area. Researches show that the appropriate food self-sufficient rate should maintain at 82.5%-84.9% in Jiangsu Province where there are good agricultural resources and the economic basis, and the best proportion of the cultivated area among grain crops, general economic crops and efficient economic crops is 68:20:12. Under the existing agricultural development level, the optimum growth potential of the scale economies should be ranging between 6.40% and 7.54%. In addition, the nonlinear model can well simulate agricultural scale curve of different self-sufficient rates of grain in Jiangsu Province and determine the land space and economic benefits of the different types of crops and economic benefits. The research results accord with the characteristics of agricultural development, which has significant influence on agricultural scale development of Jiangsu Province and other similar areas.
Taking nine cities of the Jilin Province as sample, this paper tries to explore the comprehensive evaluation system of regional urban land intensive utilization from the aspects of land use intensity, land use degree, land use benefit, and eco-envircnmental intensiveness. Using global principal components analysis of SPSS 13.0, the lever of urban land intensive utilization from 2000 to 2009 was evaluated.Then based on the scores of all factors, its variation characteristics in space was summarized using cluster analysis.
The results showed the level of urban land intensive utilization of Jilin Province improved from 2000 to 2009. The regional differences of urban land intensive utilization were obvious, but its trend of change was reducing instablely. The urban land intensive utilization displays as a core in space, the level of Changchun’s land intensive utilization is much higher than that of other cities. The spatial difference also exists as that of cities in central of Jilin is the highest, that of cities in western part is the lowest and the eastern cities having the medium level. According to the spatial difference, this paper analyses the reasons from the aspects of regional environment, scales of cities, economic growth and industrial structure. Based on the analysis, it can conclude that there are many factors affecting the urban land intensive utilization of Jilin Province, the difference of development environment is the basic reason, economic development level is the most important external factor affecting the level of urban land intensive use. The level of urban land intensive utilization is higher in developed areas, like Changchun and Songyuan higher than other cities.
Finally, this paper proposes that Jilin Province should excavate the potential of urban land intensive utilization, and avoid the expansion of urban land rapidly. So in the future, Jilin Province should make full use of urban land efficiently and reasonably, and take the way of sustainable development.
Based on land use and land cover research, land system, which is composed of land use, land cover and ecosystem, now is focusing on the study of human vulnerability and sustainability under global environmental change with an integrated perspective, and becoming the core of present land change science. Land system is interested in the functional changes caused by structural changes, and emphasizes comprehensive assessments and simulations of the coupled human-environmental system. Detailed investigations of land system can combine region and city as a whole and contribute to urban ecological safety and regional sustainability. This paper takes Harbin-Daqing-Qiqihaer region in Heilongjiang Province of Northeast China as study area,on the basis of defining land use functions conception and classification, this paper selects several indices from land use, environment and socio-economic development, and utilizes Analytical Hierarchy Process (AHP) method to identify land use functions distribution of the year 1976 and 2005 on geographical grid scale. There are four main functions (resources function, ecological function, economic function and social function) and eight sub-functions, such as resources provision, ecological defense, landscape maintenance, environmental purification, economic increase, population bearing, human habitat, culture and recreation. This paper investigates its changing hotspots and coupling relations, the results show that correlativity between resources provision function and other functions are negative, which means obvious land use functions conflicts. The framework proposed by this paper can provide spatial, quantitative and dynamic study of land use functions, and can provide references for land configuration.
In this paper, the typical desert grassland in Northern Tianshan Mountains was studied for analyzing pattern dynamic changes of desert grassland between 1990 and 2008 by means of point-line-surface methods. Human activity areas (city and agriculture) of typical grassland were used as study sites for discussing dynamic changes according to landscape ecologic method. In addition, the causes for grassland degradation were discussed from natural factors to social factors. The result showed that the areas of grassland decreased and those of agricultural and other land use types increased during the last 19 years. At the same time, grassland vegetation coverage also declined from 1990 to 2008, especially middle and high coverage grassland vegetation. In order to gain a clear cause of grassland changes, natural and social factors were discussed. The main factors of grassland area decreased and grassland degradation was caused due to human activities and unreasonable use of grassland resource. Therefore, these results implied that grassland resource reasonable and scientific utilization was the theoretical basis for grassland sustainable development.
To understand the relationships between soil loss tolerance (T value) and karst rocky desertification (KRD), T value was calculated using digital-distribution map of carbonate rock assemblages types in this paper, based on pedospheric system theory. And the impacts of T value on KRD were discussed also based on GIS and field survey comprehensively. The results showed that: 1) T values in karst areas can be divided into three categories, which are 20,100 and 250 t·km-2·a-1 respectively in the purest, purer and nonpure carbonate rock areas but only less than 20 t·km-2·a-1 in rocky mountain region. 2) In the three carbonate areas where T=20,100 and 250 t·km-2·a-1 respectively, KRD incidence rates are 29.86%, 28.12% and 23.25% with KRD severity being 73.55%, 60.57% and 52.19%. Therefore, T value in karst areas is very low, and has such characteristics as diversity and heterogeneity in spatial distribution. T value has great impacts on incidence rate and severity of rocky desertified land. In the same social context, or neglecting the differences of human activities, the lower T value is, the smaller the threshold, the weaker anti-jamming capability is, the higher KRD incidence rate is, and the more KRD severity is.
Urban construction land plays an important role in economic development in China. This study explores the driving forces of urban construction land expansion. Panel data econometric method was used to analyze relevant data of China during the period 1999 to 2008. The results showed that: 1) Urban construction land had been expanded very quickly in East China, Central China, West China and the whole country. The rate of expansion was the highest in East China, and was declining in recent years. But it was relatively slow in Central and West China. 2)Economic development, the increasing urban population and industrial structure adjustment can explain the expansion of the urban construction land of East China, Central China, West China and the whole country very well, those three variables all have positive effects on urban construction land expansion, while the influence strength varies in different regions. 3)Year by year regression results show that: economic development, the increasing urban population and industrial structure adjustment also have positive effects on the urban construction land expansion, which indicates the influence of increasing city’s population on urban construction land expansion is stable, while the influence strength of population growth is greater than those of the economic development and industrial structure adjustment, in addition, the effect of the economic development on urban construction land expansion becomes increasingly stronger, while the influence strength of the adjustment of industrial structure on urban construction land expansion becomes increasingly weaker.
Land use change and its effect is one of the hotspots of global change research. It has always been more concerned about the cultivation of agricultural land use changes in food security, but the pastoral land use change on food security impact is significant deficiencies. It is different in the concept of food security in agricultural areas and pastoral areas. Besides agricultural areas of food security, pastoral land use change on food security study also deserves attention. In this paper, Dalag County, Qinghai Province in western China was taken as a case study area, and the township was taken as research unit. A model is built including the smallest per capita grassland area and grassland pressure index to calculate the food security of each township. There are similar trends of the food security in Dalag County and 10 townships which belong to Dalag from 1987 to 2007. With the animal husbandry production conditions showing deterioration, inadequate technical and material inputs, grassland degradation is getting more serious, the population increased and real per capita grassland area decreased, while the smallest per capita grassland area and the grassland pressure index keep increasing. The calculation of the pressure index of each township in 1997 and 2007 showed that there are four levels of food security (security area, alert area, shortage area and crisis area) in 1997. The security area and the alert area did not exist in 2007, replaced by crisis area and a wide range of food shortages area. The pressure index on grassland gradually reduced from Manzhang, Xiahongke, Deang, Wosai and Jimai which lie in the eastern part with lower altitude, better climate and more human activity to Shanghongke, Moba, Jiangshe, Sangrima and Tehetu which lie in the western part, indicating that unreasonable human activities are one of the main driving forces for grassland degradation and food supply shortage. It could relieve grassland pressure status by taking active measures to control the speed of smallest per capita grassland area and improving animal husbandry technology.
In view of the status quo that few researches have been made on ecological environment evaluation of agricultural land, this paper adopts PSR framework to construct index system of evaluation, and employs the cloud theory to establish cloud models of quantitative indexes and qualitative indexes respectively so as to evaluate ecological environment of agricultural land. Taking Xinxing County as an example, the evaluation score is 0.75 representing good ecological environment in Xinxing. The result is reasonable and conforms to the current situation in Xinxing. Compared with fuzzy rules, evaluation scores are 0.75 and 0.70 respectively, showing no obvious difference. However, the results reveal that the cloud theory has the capacity to express the uncertainty completely existed in the process of evaluation and can avoid the complex procedures of choosing membership functions when fuzzy rules are constructed.
Environmental characteristics affect spatial distribution of the vegetation profoundly. The researches of regional environmental characteristics of vegetation are very significant to the protection and management of local vegetation diversity. On the basis of these researches, further researches on vegetation response to climate changes can also be completed. In this paper, we chose the Grand Shangri-la as a research area to study the relationships between local typical vegetation distribution and their environmental characteristics through Maxent model and ArcGIS spatial analysis, using the climate stations data, DEM and vegetation distribution map in this area. Then, climate and terrain characteristics of typical vegetation distribution could be acquired in this area, quantifying evaluation of the relationships between the distributions of vegetation and their habitat, relational model between vegetation and climate factors were analyzed on the basis of their statistical relation characteristics. At the same time, elevation, slope and aspect boundaries of different vegetation distributions were quantitatively defined. In the region, different vegetation distributions were affected by different climate factors. Meadows distribution was affected by annual average lowest temperature and annual average July temperature; coniferous forest distribution was affected by annual average lowest temperatures and sunshine duration; shrub distribution was affected by annual average sunshine duration and July temperature; cultural vegetation distribution was affected by annual average May to October precipitation and annual average July temperature. At the same time, these vegetations showed the different elevation and gradient distribution characteristics. 90% of the meadows concentrated within the range of 3740 m to 5000 m in elevation.90% of the coniferous forest concentrated within the range of 1796 m to 4484 m. Cultural vegetation concentrated within the range of 1000 m to 2784 m. 80% of the shrubs concentrated within the range of 3000 m to 5000 m. In different gradient, vegetation distributions were not the same. 95% of the meadows were distributed in the range of less than 40 degrees. 95% of the coniferous forests were distributed in the range of less than 45 degrees. More than 90% of the cultural vegetation were distributed in the range of less than 35 degrees. About 90% of the shrubs were distributed in the range of 6 degrees to 37 degrees. In this area, vegetation distributions didn’t show the typical aspect characteristic. In different aspects, the ratio of vegetation distribution was exactly similar. The results from the above analysis provided the reference for vegetation diversity protection, vegetation management and vegetation response to climate change.
Tarim River Basin, Manas River Basin, Shiyanghe River Basin and Heihe River Basin have been taken as typical regions and hot spot to study value of ecosystem services. Studies on land use/land cover changes and their landscape ecological function were carried out by GIS according to landscape ecology principles on the basis of TM in 1994 and CBERS in 2005. Price of cropland, forest, grassland and water ecosystem services in typical river basins were carried out by "equivalent weight factor of ecosystem services per hectare of ecosystems in China: combining with the Engel coefficient(household expenditure on food). It was found that the area of forest, grassland and water ecosystem decreased in large, but the area of cropland ecosystem increased intensively. Comparing the larger area of the river basin with the smaller one, area of the latter changed greatly, and the ratio of change was more quickly. The economic value of ecosystem services in Tarim River Basin was maximal, which was scarcity. The increasing extent of ecosystem services in Heihe River Basin was maximal. Comparing the Tarim River Basin with Heihe River Basin, the ecosystem services function of the latter impacted more on the lives and yield of typical population. The increasing extent of cropland ecosystem area in the Tarim River Basin was maximal, but the price of the ecosystem services value kept the lowest. It was found that the payment willingness of the population was anisomerous with the economic value of ecosystem services function in the Tarim River Basin. It was important to reinforce the sustainable development idea of environment protection and economic development.
Taibai Mountain, the peak of Qinling Mountains, is located in the middle hinterland of Qinling Mountains. Based on NDVI data of Taibai Mountains Nature Reserve in May which were derived from remote sensing and in site survey, we analyzed the spatial-temporal changes of vegetation index for different vegetation zones during 1979 to 2009, as well as their responses to temperature. The results showed that the area where the average NDVI in May was higher than 0.2 accounts for 89.5% of the total Taibai Mountain, which indicates a good vegetation cover in the mountain nowadays. However, the significant vertical deviation was found in NDVI. The value of NDVI is generally over 0.2 for the low altitude regions while ranges from 0.2 to 0.5 for the high altitude regions. The pixles where NDVI increased and decreased significantly during the past three decades account for 4.88% and 3.92%, respectively, and no change was found in about 56% of the total pixles. The annual mean temperature in the study area tends to increase with a slope of 0.35℃/10 a during the last 30 years. The vegetation changes became more sensitive to temperature with the increase of altitude, which indicates that the ecosystem of Taibai Mountain that is characterized by a small human disturbance and a high elevation deviation has become a sensitive place responding to climate change.
Many results showed fertilization enhanced plant assimulation. But it’s not clear that whether these assimulation products will have effect on soil dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) or not. And whether that will make changes to soil quality, especially in arid and semiarid regions, such as the Loess Plateau in China. Therefore, a field trial was carried out with ryegrass as indicative crop in wind-water erosion crisscross region on the Loess Plateau, to study the effect of fertilization on the contents and accumulations of DOC and DON in farm soil. The results showed that both the application of nitrogen fertilizer and phosphorus fertilizer increased the above-ground and root biomass of ryegrass. And the relative relation is very significant between them. There was no obvious effect on the content of DOC when only phosphorus was applied to soil. The content of DOC decreased with the application of nitrogen fertilizer. And the largest decrease amplitude, 25.9%, was found in 0-20 cm by PN4 treatment in 2008. There was no significant decrease in the content of DON in the soil where only phosphorus applied. But the content of DON increased in its degree in different soil layers with the application of nitrogen fertilizer. There was an obviously positive correction between accumulation of DON and N fertilizer. And both the correction coefficients of 2007 and 2008 was 0.99 (n=5). The result indicated that the chemical nitrogen application was in favor of the biomass and DON in the region, but was against DOC. It suggested higher chemical nitrogen application was of beneficial to the increase of soil nitrogen supply capacity in wind-water erosion crisscross region on the Loess Plateau.
The information which includes land use, vegetation cover and slope, was extracted by combining "3S" techniques with field investigation in the research region of Fujian Province, and the distribution maps of soil and water loss in the year of 1995, 2000 and 2007 were compiled. Moreover, the soil and water loss intensities for 1995, 2000 and 2007 were analyzed respectively by means of Geostatistics. The results show that the soil and water loss intensities can be exactly simulated by the semivariograms of spherical models. The soil and water loss intensities are nearly NNE-SSW directions which are consistent with the topographic orientation. The sill values about the soil and water loss intensities decrease, which means the soil and water loss intensities become weaker and evener. The proportions of structural variance values and nugget variance values are 12.31% and 87.69% (1995), 3.51% and 96.49% (2000), and 2.94% and 97.06% (2007) respectively. The proportions of stochastic factors are bigger than structural factors and increase with the time, which means the soil and water loss intensities are closely connected with many factors, and anthropogenic activity is one of the most important factors. Furthermore, the stochastic factors are predominant in small scale, whereas the structural factors are predominant in medium scale. The connotations of structural factors and stochastic factors need further analysis, and natural factors and anthropogenic activity must be considered simultaneously for the spatial variability of soil and water loss in small scale.
In this paper, the runoff change in the Minjiang River Basin is investigated and its response to main meteorological elements is explored based on the monthly runoff, precipitation and temperature data from 1960 to 2006. The adopted methods include Mann-Kendall trend analysis and empirical mode decomposition. The results are as follows: First, the annual runoff in the Minjiang River Basin is on the increase, and the runoff in the non-flood season contributes a lot to this increase. The trend of autumn and winter runoff is upward for most of the time. The runoff in summer has been on the increase while the runoff in spring on the decrease since the 1990s. Second, both precipitation and temperature of the basin increased for the study period, especially for temperature series. And the upward trend of runoff is more evident than that of precipitation. Third, multi-scale characteristics of runoff and precipitation have been detected and the periods of precipitation are longer than those of the runoff. The amplitude of decadal variability in the precipitation and runoff series has been weakened while the amplitude of inter-annual variability has been intensified since the 1980s. The paper revealed that the reason for runoff increase to be more evident than precipitation increase is that the evaportranspiration is on the decrease and precipitation intensity is on the increase in the basin. What’s more, the influences of underlying surface also contribute to runoff increase.
As a demonstration from the three rivers of the Aksu River Basin, the paper checked the nonlinear characteristics of annual runoff processes from 1957 to 2008 by using the wavelet analysis method and R/S analysis. The main conclusions are as follows: The annual runoff trends of the mainstream of Aksu River, the Kumlak River and Tuoshigan River are increasing; the trends are divided into two parts: the runoff is less in the prophase and more in the latter period. The time series of runoff in Aksu River all has long cycles, which contains some short ones. The period of 18 years and 22 years is the first period, which is through all the time sequence. The Hurst index of the three rivers in the Aksu River Basin is over 0.5 in each period, which indicates that the time series of runoff have the long trend. The Hurst index of each river in the last period indicates that the annual runoff in the Aksu River Basin will show an increasing trend in the future.
Process of hydrological cycle is the basis of water resources reasonable allocation. With the characteristic of multi-time transformation and the pattern of the reutilization of water resources in the inland river basin, this paper attempts to establish an optimal allocation model based on the simulation of water resources transformation. The inland river basin is divided into three independent subsystems according to hydraulic connection. An independent subsystem is divided into three primary calculation units of canal irrigation district, well irrigation district and mixed canal and well irrigation district according to the characteristic of water resources transformation and pattern of water utilization. A primary calculation unit includes several irrigation districts (secondary calculated units). Two models of water balance and BP artificial neural network were established to simulate inflow of well irrigation district and mixed canal and well irrigation district respectively. Two-layer optimal models of primary and secondary were established to allocate water resources between primary and secondary calculation units respectively, with the objectives of maximum irrigation benefit and equity respectively. The optimal results of water resources allocation were obtained by the solution of simulation optimizing and genetic algorithms through combining the two simulation models. And the water resources of irrigation district and administrative district were allocated with Liangzhou 10.68×108m3 and Jinchuan 2.63×108m3, irrigation water is 16.61×108m3 which is 75% of the whole basin water and reduced greatly when compared with present water use. The unity of allocation of basin and administrative district will be realized.
Material and energy flow is necessary to ensure the normal running of economic and environmental system. In order to improve resource productivity and solve environmental problems fundamentally, it is essential to research the metabolism process and environmental impact when we transform raw materials and energy into products and wastes. Based on the methodology of regional material flow analysis, energy flow analysis, ecological footprint and emergy analysis, the concept, research framework and analysis indicators of regional material and energy flow analysis were proposed, and then applied to analyse the economic and environmental system of Tianjin during 1998-2007. The analysis results indicated: the total material consumption was 97.25 million t, and the total energy consumption was 47.15 t (coalequivalent) in 2007, with the average annual growth rate of over 10% and 8% respectively; the outside resource input occupied about 46% in direct material input, of which 40% of outside resource input was coal from outside region completely; low resource output ratio and high intensity of resource consumption led to large consumption of resources and continuous increase of total emission of pollutants, which brought great pressure to the regional resource and environmental system, and made the environmental capacity of pollutants in saturated condition on the whole. Finally, the corresponding suggestions were proposed in view of the existing problems.
It’s very prevalent that groundwater is polluted by nitrate. However, its remediation is also difficult because of the presence of oxygen and the absence of electron donor. In this paper, three experimental studies including microcosms, sand column and sand tank, were introduced. Their results showed that ethanol used as electron donor could largely stimulate the bioremoval of nitrate in groundwater. Because dissolved oxygen (DO) was usually limited in groundwater, the impact of DO on the rate of denitrification was short-lived. Actually, both DO and nitrate in the center of ethanol plume were often below detection. As ethanol can be used by many indigenous microorganisms with high biochemical oxygen demand, and it is miscible and unretarded in water, the use of ethanol as electron donor in the nitrate-contaminated groundwater bioremediation has high availability.
