Dynamic Changes of Land Ecological Carrying Capacity Based on the Ecological Footprint——By the Case Study of Chengdu City

Chengdu City is in the period of rapid urbanization and industrialization, and the disturbance derived from human activities on environment is increasing remarkablely in recent 20 years. The pressure on environment, economy and population is also increasing and land use in Chengdu has changed enormously. As struc- ture and function of land ecological system change obviously, sustainable development of land productivity has been an important goal and strategic task from now on, and it is necessary to systematically research land ecological carrying capacity based on ecological footprint. The ecological footprint of Chengdu City in the past ten years was calculated and analyzed from the spatial and temporal aspects according to statistical data from 1998 to 2008, as per ecological footprint method, ecological carrying capacity and the GIS spatial analysis method, and regression analysis method. The ecological footprint and ecological carrying capacity values from 2009 to 2019 in Chengdu City were predicted through calculation results in the past ten years. The results show that the ecological footprint and ecological deficit of land use from 1998 to 2008 increased in Chengdu City. The ecological deficit of land use within the city center was in high levels in the past ten years, and the ecological footprint kept raising, especially in areas, such as Shuangliu, Chongzhou, Qingyang among 9 city areas, 4 counties and 6 districts in Chengdu City. There is fanlike distribution of ecological deficit of land use. Analysis shows that the social and natural ecological system is uneven distribution, which is not in sustainable de- velopment situation. The results of the study show that the economic, social and natural ecological system in Chengdu City is not sustainable, and the ecological foot- print is uneven distribution. The analysis of the dynamic change of land ecological carrying capacity in Chengdu City is very important for city government in the pro- cess of the vigorous development in new Tianfu Xinqu, and redevelopment in the northern part of this city.

略论张竞生晚年的三部哲学手稿

张竞生晚年先后写作了三部哲学手稿。《自然系统法》对自然系统法的构成、内涵及其结构定律,从科学的角度进行了阐释;《哲学系统》在阐明系统与规律的异同后,又特别强调了系统的创造性;《记忆与意识》讨论记忆与知识的关系,对感觉、知觉及表象的不同机制进行了揭示。他的以系统为中心所进行的一系列的探索,大多从科学的观察出发,从逻辑上进行推演,具有科学哲学的特色。

Research Progress in Agricultural Vulnerability to Climate Change

With the deepening of climate change research, more attention has been paid to vulnerability to climate change. Compared with water resources, forests and other natural ecosystems, agriculture is more vulnerable to climate change, thereby scientifically assessing agricultural vulnerability to climate change is of great significance to the formulation of rational and effective adaptation strategies. In this paper, the authors give a comprehensive review of the research from the perspective of the definition of climate change vulnerability and agricultural vulnerability to climate change, research topics, and evaluation methodologies. Existing problems in current research, including scenario application, methods, and uncertainties, are analyzed, and meanwhile, a vision of the direction for future research in assessment of agricultural vulnerability is also presented.

Research on the Automatic Pattem Abstraction and Recognition Methodology for Large-scale Database System based on Natural Language Processing

In this research paper, we research on the automatic pattern abstraction and recognition method for large-scale database system based on natural language processing. In distributed database, through the network connection between nodes, data across different nodes and even regional distribution are well recognized. In order to reduce data redundancy and model design of the database will usually contain a lot of forms we combine the NLP theory to optimize the traditional method. The experimental analysis and simulation proves the correctness of our method.

Integrated risk assessment of complex disaster system based on a non-linear information dynamics model

This paper describes a non-linear information dynamics model for integrated risk assessment of complex disaster system from an evolution perspective. According to the occurrence and evolution of natural disaster system with complicated and nonlinear characteristics, a non-linear information dynamics mode is introduced based on the maximum flux principle during modeling process to study the integrated risk assessment of complex disaster system. Based on the non-equilibrium statistical mechanics method, a stochastic evolution equation of this system is established. The integrated risk assessment of complex disaster system can be achieved by giving reasonable weights of each evaluation index to stabilize the system. The new model reveals the formation pattern of risk grade and the dynamics law of evolution. Meanwhile, a method is developed to solve the dynamics evolution equations of complex system through the self-organization feature map algorithm. The proposed method has been used in complex disaster integrated risk assessment for 31 provinces, cities and autonomous regions in China mainland. The results have indicated that the model is objective and effective.

Winners and losers among tree species in Xishuangbanna: which traits are most important?

Massive human interference in natural ecosystems is resulting in a few ＂winners＂ and many ＂losers＂. However, the drivers of this winner-loser replacement pattern remain poorly understood. The aim of the study reported here was to identify winners among the tree flora of Xishuangbanna and compare their functional traits, specific leaf area （SLA）, wood density （WD）, seed mass （SM） and maximum height （MH） with previously identified losers （i.e., endangered species）. Fifteen native tree species were identified as winners from expert opinion, plot-based surveys of secondary forests and plotless surveys along roads. Twelve endangered tree species for which trait information could be obtained were used for comparison. Traits were compared with a Wilcoxon rank-sum test. Winners had significantly higher SLA, but lower WD. SM and MH did not differ significantly between groups. When the effects of phylogeny were removed by using phylogenetic generalized least squares, the difference in SLA became marginally insignificant. Principal component analysis resulted in two overlapping groups, showing that the selected traits were insufficient to distinguish winners and losers. Our results suggest that the ＂few winners, many losers＂ paradigm applies to trees in Xishuangbanna, with15 species accounting for most trees in the disturbed habitats sampled.

Reserve network planning for fishes in the middle and lower Yangtze River basin by systematic conservation approaches

Although China has established more than 600 wetland nature reserves, conservation gaps still exist for many species, especially for freshwater fishes. Underlying this problem is the fact that top-level planning is missing in the construction of nature reserves. To promote the development of nature reserves for fishes, this study took the middle and lower reaches of the Yangtze River basin(MLYRB) as an example to carry out top-level reserve network planning for fishes using approaches of systematic conservation planning. Typical fish species living in freshwater habitats were defined and considered in the planning. Based on sample data collected from large quantities of literatures, continuous distribution patterns of 142 fishes were obtained with species distribution modeling and subsequent processing, and the distributions of another eleven species were artificially designated. With the distribution pattern of species, Marxan was used to carry out conservation planning. To obtain ideal solutions with representativeness, persistence, and efficiency, parameters were set with careful consideration regarding existing wetland reserves, human disturbances, hydrological connectivity, and representation targets of species. Marxan produced the selection frequency of planning units(PUs) and a best solution. Selection frequency indicates the relative protection importance of a PU. The best solution is a representative of ideal fish reserve networks. Both of the PUs with high selection frequency and those in the best solution have low proportions included in existing wetland nature reserves, suggesting that there are significant conservation gaps for fish species in MLYRB. The best solution could serve as a reference for establishing a fish reserve network in the MLYRB. There is great flexibility for replacing selected PUs in the solution, and such flexibility facilitates the implementation of the solution in reality in case of unexpected obstacles. Further, we suggested adopting a freshwater management framework in the implementation of such solution.