The environment,especially the minimum temperature,affects summer maize grain yield by regulating ear differentiation and grain development

Ear differentiation,grain development and their interaction with factors in the growing environment,such as temperature,solar radiation and precipitation,greatly influence grain number and grain weight,and ultimately affect summer maize production.In this study,field experiments involving different sowing dates were conducted over three years to evaluate the effects of temperature factors,average solar radiation and total precipitation on the growth process,ear differentiation,fertilization characteristics,grain filling and yield of summer maize varieties with different growth durations.Four hybrids were evaluated in Huang-Huai-Hai Plain(HHHP),China from 2018 to 2020 with five different sowing dates.The results showed that the grain yield formation of summer maize was strongly impacted by the environment from the silking(R1)to milking(R3)stage.Average minimum temperature(AT_(min))was the key environmental factor that determined yield.Reductions in the length of the growing season(r=–0.556,P<0.01)and the total floret number on ear(R^(2)=0.200,P<0.001)were found when AT_(min) was elevated from the emerging(VE)to R1 stage.Both grain-filling rate(R^(2)=0.520,P<0.001)and the floret abortion rate on ear(R^(2)=0.437,P<0.001)showed quadratic relationships with AT_(min) from the R1 to physiological maturity(R6)stage,while the number of days after the R1 stage(r=–0.756,P<0.01)was negatively correlated with AT_(min).An increase in AT_(min) was beneficial for the promotion of yield when it did not exceeded a certain level(above 23°C during the R1–R3 stage and 20–21°C during the R1-R6 stage).Enhanced solar radiation and precipitation during R1–R6 increased the grain-filling rate(R^(2)=0.562,P<0.001 and R^(2)=0.229,P<0.05,respectively).Compared with short-season hybrids,full-season hybrids showed much greater suitability for a critical environment.The coordinated regulation of AT_(min),ear differentiation and grain development at the pre-and post-silking stages improved maize yield by increasing total floret number and grain-filling rate,and by reducing the floret abortion rate on ear.

Relation between Economic Development Level and Resource and Environment Carrying Capacity of Central Area of Yunnan Province Based on Decoupling Analysis

Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that （i） the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse ＂N＂ in temporal changes. （ii） Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse ＂V＂ change. （iii） The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod.

Research on Environmental Problems during Island Tourism Development in China

Due to the weakness of island eco-environment and the dependence of tourism development on island environment,it urgently needs to make a study on environmental problems during island tourism development,so as to provide a reference for the sustainable development of island tourism.The paper has concluded Chinese island environmental characteristics,analyzed the current situation of island tourism development and discussed environmental problems during island tourism development.On this basis,it has proposed some suggestions for island tourism environment protection.It should take island eco-environment protection as the premise and complete relevant laws and regulations;take foreign island tourism development as the reference,plan scientifically and build island eco-tourism mode;improve island infrastructures,prevent environmental pollution and protect island tourism environment with the government as the guidance;establish island environment monitoring station and tourism information monitoring station;enhance eco-environment protection education and cultivate responsible tourists and tourism staff;and intensify island supervision and regularize island tourism order.

A STUDY ON THE FORECAST AND REGULATION OF COORDINATED DEVELOPMENT OF URBAN ENVIRONMENT AND ECONOMY IN GUANGZHOU

This article introduces the concepts of coordinated development of economy and environment and formulas of coordinated degree. Results obtained are that the coordinated degree in 1992 is over 0.87.The variation tendencies on coordinated development of urb

Issues of Agricultural Sustainable Development in Environment with Limited Resources——A Case Study of Xinjiang

Based on natural resources in Xinjiang, some problems existing in agricul- tural sustainable development in Xinjiang were explored, such as simple agricultural structure （unbalanced development in different regions）, dispersed production pattern, and lower efficient water use for agriculture. Furthermore, some countermeasures for Xinjiang agricultural sustainable development were proposed as well, including ad- justment of agricultural structure for optimization of resource allocation, strict control of population for improvement of people education, strengthening of S＆T innovation for popularization of sustainable development, and construction of macro-adjustment mechanism of resources use for virtuous environment.

Resource and Environmental Quality Changes and Adjustment Principles for Sustainable Development in Rapidly Developing Coastal Region of Southeastern China

Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns in China, and the large export-oriented economy makes itself a strategic importance while China enters into international markets. The problems facing to this region include arable land reduction, land degradation aggravation, high percentage of built-up land with high rate of expansion, expanded non-point pollution, deteriorated water quality, decreasing biodiversity, destroyed ecosystems, severe air pollution, frequently occurred acid rain, and multi-pollutants. The important research fields in the near future should include a) influence of high-intensity exploitation of resources on changes of environment quality and its feedback; b) interface processes, key mechanisms and adjustment principles for degradation of water-, land-, and air-resources and environmental quality; c) evolvement processes and nurturing theory of biodiversity and ecological resources; and d) spatio-temporal variation and human-induced effects on regional resources and environment quality. Strategies for sustainable development in the region are as follows: a) controlling to ensure basic cultivated land area; b) enforcing remediation of polluted water environment, and controlling non-point pollution; c) strengthening ecological construction and ecological security; and d) controlling multi-pollution and preventing trace toxic pollutants.

Development and Utilization of Saline Lake Resources and Protection of Ecological Environment in Qaidam Basin in Qinghai Province

Qaidam basin is an important part of National Key Development Area–Lanzhou-Xining Area,is a key region of resource development in Western Development,is a National Circular Economy Pilot Zone.The focus of

Existing Problems in Energy Exploitation and Eco-environment Sustainable Development and Their Countermeasures in Northern Shaanxi

The exploitation of coal, petroleum and natural gas in northern Shaanxi not only promoted the rapid development of economy, but also brought about enormous pressure to fragile ecology and resulted to severe water pollution, water and soil loss, vegetation destruction and other ecological environmental problems, so many countermeasures were put forward according to these problems, such as greatly developing circular economy, conducting cleaner production in petroleum enterprises, continuously renewing mining technology and so on.

China’s environmental scientific research and technology development:review and envisage

The topic was concentrated on environmental technology development in China within the context of China's economic acceleration and reform. Firstly, cleaner technology should be adopted where possible in industrial production; secondly, eco agricultural technological system, especially biological technology, should be developed in agricultural production; thirdly, end of pipe solution should focus on waste utilization or recycling technology where appropriate clean technology does not exist; lastly but not the least, existing technologies to minimize eco environmental deterioration such as soil erosion, salinization, desertification and deforestation should also be extended and developed. The mentioned ways of environmental technology development can only be realized on the condition that a resource conservation based production system and life style could be established and appropriate policy secured.

Environmental management and sustainable development in forested mountain areas of northeast China

This paper studied the sustainable development through a reasonable management of the social, economic and natural environment in a forested mountain area of northeast China. In order to show the local people how to manage their most important forest resource, we analyzed the life-history process of the key species and the influencing factors that were associated with the forest regeneration and sustainability. Pollination and fertilization were mainly affected by weather conditions. Light intensity under the forest canopy was the key factor that controlled seedlings growth and saplings survival. Periodic seeds setting caused the fluctuations of rodents and other related animals in the food chain. Squirrels played a very important role in the forest regeneration, theses animals were the absolutely indispensable components of the forest ecosystem. How to understand the co-evolutionary relationships among species in the forest ecosystems was very important for the conservation of biodiversity and maintenance of ecosystem itegrity. In conservation of the natural resources, we studied the social and economic environment of the forested mountain area. It is very hard to effectively protect the forest resources and maintain the normal life of the local people under the regime of the “unified administration and enterprise system”. Reforms are needed both in administrative institutions and in enterprise management. In the end, this paper proposed that we should not only protect the trees, the related animals, the ecological habitats, and the whole forest ecosystems, but also consider the human activities and their basic requirements so as to realize a sustainable development in the forested mountain areas.

Eco-geographic Environment and Regional Development in Xinjiang of China

The study on relationship between eco-geographic environment （EGE） and regional development （RD） is of theoretical and practical significance to promote the comprehensive study on nature and human factors and regional coordination development. Based on the evaluation index system and models of EGE and RD, Quadrant Analysis Method （QAM） and the Coordination Degree and Coordinated Development Degree Model （CDCDDM） were applied to studying the relationship between EGE and RD in Xinjiang in this paper. The results show that Xinjiang can be divided into four type regions according to the relationship between EGE and RD, namely high coordination region （HCR）, overloading development region （ODR）, low coordination region （LCR） and potential development region （PDR）. Most areas of Xinjiang belong to LCR which can not bear a larger population and support large-scale economic development. HCR, ODR and PDR, which are mainly distributed in piedmont oases and take basin as unit, should be focused on in the development of Xinjiang. The EGE has great influence on RE）, and there is serious contradiction between them. Relevant suggestions on development strategies were put forward according to the character of different type regions, and the key regions of macro-layout of RD in Xinjiang were pointed out.

On coordinated development of oasis and environment in arid area

Based upon the formation and evolution of oasis and the factors restricting the coordinated development of oasis economy and environment, this paper presents a goal of the development in coordination. It suggests that the sustainable survival and development of oasis could be ensured only if the oasis-desert and water source ecology are managed in a combined way to form a macro system. In light with the above mentioned, the approach to the development of economy and environment of oasis in arid area should depend upon the establishment of an oasis ecological and economic system, which suits the arid environment and promotes the efficiency of resource configuration, stabilizes economic increment and benefits ecological development.

Tourism Development and Ecological Environment Protection

This paper defined tourism environment, analyzed the impact of tourism development on the water environment, soil, vegetation and landscape and proposed main measures for protecting tourism environment on this basis.

Optimization of harmonious development on regional energy－economy－atmospheric environment system

The energy,industrial economy and atmospheric environment were taken into account as a whole cornplex system in this study. Based on the application of grey system theory and the analysis of development coefficients about major parameters of the system,the method of grey developrnent decision was approached, and a new concept-integrated development coefficient was put forward. Furthermore,the reasonable ranking of development decision within eight industrial sectors(building materials,coking,food and drink,chemical engineering,paper rnaking,machinery and electrical appliance,textile, mining)has been concluded from the viewpoint of economic growth, energy saving and ambient air quality protection.

PROBLEMS AND COUNTERMEASURES FOR RESOURCES DEVELOPMENT AND ENVIRONMENTAL RENOVATION IN THE CONTIGUOUS AREA OF SHANXI,SHAANXI AND INNER MONGOLIA

The studied area consists of 16 counties belonging to 3 provinces or autonomous re-gion, which are Hequ, Baode, Pianguan and Xinxian counties of Shanxi Province; Yulin,Shenmu, Fugu, Hengshan, Jingbian and Dingbian counties of Shaanxi Province;Dongsheng, Tuoketuo, Qingshuihe counties and Yijinhuoluo, Dalate, Zhungeer banners

City Environment Art and Sustainable Development

The development of everthing follows its own law, which does not change at people’s own sweet will. Therefore, we must study the development of things so as to grasp the essence of things in their deep meanings, explore the direction of their de- velopment, and make them better serve the people. As a part of the thought of sustainable development, city environment art will be of active significance to the perfection of the thought and will also be the concrete embodiment of the synthetic index of economic development. Such a thesis, starting from the macroscopic angle, and relying on the leading thought of sustainable development, takes hold of the development trend of city environment art, and explores the various problems that have arisen in city environment in the process of city management by combining thoughts on city planning, so as to guide urban harmonious development theoretically. The present paper expounds on the views comprehensively and, through the synthetic analysis on city planning, city environment, art esthetics and the thought of sustainable development, makes a detailed analysis of the effects of the present rapid city development on city environment.

Modeling Indicator Systems for Evaluating Environmental Sustainable Development Based on Factor Analysis

Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the parameter estimation, the factor rotation and the factor score. Under the condition that the cumulative proportion is greater than 85%, 5 explicit factors of environmental sustainable development as well as its factor score by region are carried out. The result indicates some impact factors to the basin environmental in descending sort order are volume of water, volume of waste gas discharge,volume of solid wasters.the degree to comprehensive utilization of waste gas, waste water and solid wastes, the emission volume of waste gas, waste water and solid wastes. It is helpful and important to provide decision support for constituting sustainable development strategies and evaluate the sustainable development status of each city.

Dynamic Analysis of Coupling Relationship between Economic Development and Ecological Environment Based on Entropy Method——A Case Study of Xi'an City

[Objective] The aim was to study the coupling relationship between economic development and ecological environment. [Method] Firstly, the evaluation index system for the coupling system of economic development and ecological environment in Xi’an City was established, then the dynamic variation of coupling relationship between economic development and ecological environment in Xi’an City from 2001 to 2010 was analyzed by using entropy method, finally some corresponding suggestions were put forward according to the problems in the current development model. [Result] The economic development and ecological environment of Xi’an have made a significant upgrading and improvement from 2001 to 2010, namely showing a stable upward trend on the whole, and were in a well-coordinated development state in 2010. However, the development level of ecological environment obviously lagged behind economic development level. In addition, there were obvious differences in the development rate of sub-systems, that is, economic efficiency and economic level developed rapidly, while the carrying capacity of ecological environment and economic vitality grew slowly and unstably. [Conclusion] The research could provide theoretical bases for the establishment of strategies for the coordinated development economy and environment in Xi’an City.

Sustainable Development and the Basic Value of Natural Environment

Contrast with artificial environment, the multi-level self-organizational system of nature has great gain. Sustain-able material environment should respect nature: non-rubbish and super-cycle quality of natural ecosystem offers the material source of human development, fractal structure of nature offers new field of space and information source to this high-density and information-based society, dissipative structure of nature links the new system of energy with whole ecosystem organi-cally, and life-chain regulation is the base of sustainable life environment. Nature guarantees the physical healthy environ-ment by its all-dimension healthy factor, constructs the mental healthy environment by its quality of co-ordinate and chaos, so that guarantees the whole emergence of sustainable develop-ment on the 'super-science' level. In the view of sustainable development, construction, green economy and human health are basic fields. With the concept of ecosystem regulation, we can relate these fields organically and fulfill the task of human health, welfare and sustainable development. Ecosystem regulation is the base of sustainable development's new para-digm.