Comprehensive Control of Ecological Environment in Water Sources

To scientifically and effectively conduct comprehensive control of water sources to achieve water safety,the importance,main steps and plan of comprehensive control of ecological environment in water sources were analyzed on the basis of analyzing the development and protection process of foreign water sources.The results show that for the comprehensive control of water sources,it is needed to pay attention to the accurate grasp of the current environmental quality of water sources and carefully analyze the problems in the ecological environment of water sources.Besides,it is necessary to ensure the water quality and quantity of sources,focus on the implementation of environmental remediation and ecological restoration,implement regional protection of water sources,and combine engineering and non-engineering measures to take comprehensive control of environmental problems.

Influence of Wall Effect on Comprehensive Controllability for Ducted Fan Aircraft

A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification of the whole prototype model.Based on the duct test bench experiment and computational fluid dynamics(CFD)simulation analysis,the expressions between the different distances dWE from the rotor center of the prototype to the wall and the thrust,reaction torque,and tilting moment of the system under hovering conditions are obtained.The influence of the wall effect of the prototype is incorporated into the system model to analyze the relationship between distance dWE and the comprehensive controllability of the system.The results show that the system comprehensive controllability vector of other channels changes little with the decrease of the distance dWE,and only the controllability vector of the rolling channel increases significantly.At the same time,the tilting moment also increases significantly,which strengthens the tendency of the prototype to tilt towards the wall.

Comprehensive Prevention and Control Technology of Vegetable Diseases and Pests in Shandong Province

An in-depth research and practice has been conducted on vegetable diseases and pests in Shandong Province,and the principles of comprehensive and ecological control of diseases and pests are put forward,including agricultural control measures such as crop rotation,field cleaning,fertilizer and water management,physical control measures such as catching and killing,trapping,blocking,photoelectric energy treatment,biological control measures such as the use of natural enemies,pathogenic microorganisms,other beneficial organisms and metabolites,and scientific and rational chemical control measures.Comprehensive prevention and control not only controls vegetable diseases and pests effectively,but also protects the ecological environment.

Occurrence Factors and Comprehensive Prevention and Control of Chinese Rose Black Spot(Actinonema rosae)

In addition to conventional techniques,the prevention and control of Chinese rose black spot(Actinonema rosae)should be strengthened in the management of Chinese rose.The occurrence of Chinese rose black spot is closely related to plant residues,rainfall,cultivation conditions and varieties.On the basis of understanding the symptoms and occurrence regularity of Chinese rose black spot,combination measures of agricultural and chemical prevention and control should be taken.

Research Progress on Prevention and Control Technology of Empoasca vitis Gthe in Tea Garden

The tea green leafhopper Empoasca vitis Gthe,one of major tea insect pests in China's Mainland,grows concealed with small size,rapid reproduction and overlapped generations,which has become the most serious insect pest in tea garden. This paper described the morphological features,damage modes and occurrence characteristics of E. vitis,and preliminarily summarized the main control methods in recent years. Therefore,from pollution-free and green control perspective,controlling population quantity of E. vitis safely and effectively and reducing the yield loss of tea has become a hot issue in prevention and control of insect pests in tea garden. The paper provided a reference in green comprehensive prevention of insect pests in tea garden.

Occurrence and Control of Pear Rust in Eastern Hebei Province

In recent years, pear rust sometimes occurs in eastern Hebei area, resulting in early defoliation, fruit abscission and loss of fruit commodity value. In this paper, the incidence symptoms, regularity and causes of pear rust are summarized, and the comprehensive prevention and control measures of pear rust in eastern Hebei are put forward.

Integrated Prevention and Control Technology of Major Diseases and Insect Pests of Strawberry

In order to effectively deal with the problems of diseases and insect pests in the growth process of strawberry and to improve the quality and yield of strawberry,the main diseases and insect pests in strawberry cultivation such as powdery mildew,gray mold,anthracnose,red stele root rot,calcium deficiency,salt or fertilizer damage,aphids,red spiders,thrips,grubs,etc.and their identification methods were analyzed.The comprehensive pollution-free prevention and control techniques of these pests and diseases were explored,in order to provide technical guidance for high quality,efficient and harmless production of strawberry.

Prevalence Characteristics of Rice Black-streaked Dwarf Virus Disease and Continuous Control Strategies

Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivation systems,the increase in the population of venomous Laodelphax striatellus Fallén and its own migration and spread,the poor disease resistance of cultivated varieties,and inadequate time of prevention and control.Besides,based on the practice of local control,it came up with some comprehensive control measures including strengthening monitoring,early warning and forecasting,planting resistant(tolerant)rice varieties according to local conditions,appropriately delaying the sowing(planting)period,supplemented by insect nets to cover seedlings,and making scientific use of chemical control.It is expected to provide a reference for the prevention and control of RBSDVD.

Occurrence Dynamics and Countermeasure of Wheat Crown Rot in Weifang City

Wheat crown rot was first found in Weifang City in 2015,and now has become a major disease of wheat,showing an aggravating trend year by year.The author investigated the occurrence area and characteristics of wheat crown rot in Weifang City over the past 5 years,and analyzed the causes of the disease.The disease was mainly related to variety resistance and farming system.According to the occurrence regularity of the disease,a set of comprehensive control measures were put forward.

Reflections and Explorations on the Decremented Regulation of Construction Land in the New Beijing City Master Planning

Construction land use has always been a key point for the planning department to practice national transformation strategy. In the new round of compilation of Beijing City Master Plan, the management of construction land use is under the rigid restriction of the bearing capacity of resources and the environment. Setting the upper-limit of the population size, a general strategy of decremented development of urban-rural construction land has been put forward, in order to realize a transition from quantitative expansion planning to qualitative upgrading planning. By "decremented development," "decremented" means a more rigid bottom-line restriction, and "development" means a more scientific allocation of resources. From the master planning level, the new Beijing City Master Plan establishes a comprehensive control framework and restrictive index system from perspectives including land use scale, construction scale, space boundary, urban and rural structure, land use structure, and cross-boundary collaboration; and in practice, it promotes strict management methods by setting up a dismantle-construction land ratio, dismantle-construction building area ratio, employment and residence land ratio, and "two lines and three districts," which is an exploration on the planning management method of construction land use that is stock-based and decremented master planning. Considering that decremented development is a major reform and a special challenge to planning implementation, the Beijing City Master Plan carries out explorations in terms of the planning management method, land policy, jurisdiction division, assessment and supervision, etc.