Prospects and limitations of soil amendment and irrigation techniques for the water-saving public urban greenery and ephemeral weed management in the sandy soils of the United Arab Emirates

Public urban greenery greatly contributes to the residential and tourist value of cities in the Gulf Region,but due to the hyper-arid climatic conditions,the cost of irrigation and plant maintenance is very high.Existing strategies to reduce the monetary and ecological costs involve the cultivation of native xerophytic plantations,and/or the use of soil improvers to increase water-and nutrient-holding capacity of the sandy soils.Various soil improvers based on mineral,organic,or synthetic materials have entered the United Arab Emirates(UAE)market in recent years,but there is considerable uncertainty about how they should best be used in combination with ornamental plant stands involving xerophytic native plants.The present study investigated the effect of soil amendment and deep pipe irrigation on perennial ornamental plant stands involving native plants(Tephrosia appolinea(Gel.)Link in combination with Aerva javanica(Burm.f.)Juss.ex Schult.)and native-exotic plants(T.appolinea in combination with Ruelia simplex C.Wright)either or not topsoil and subsoil amendment with bentonite and hydrophobic sand under the irrigation water supply of less than 50%of reference evapotranspiration(ET0).After one year of cultivation,T.appolinea and A.javanica(native vs.native)produced high biomass and exhibited high water use efficiency(WUE)as compared with T.appolinea and R.simplex(native vs.exotic)combination given that no significant differences were found under the soil amendment treatments.All stands thrived under irrigation water supply far below what is usually supplied to exotic ornamental stands in public parks of the Al Ain City,the UAE.However,subsoil amendment in combination with deep pipe irrigation reduced the occurrence of weeds and increased the overall plant rooting depth.Our results suggest that subsoil amendment and irrigation up to 60-80 cm depth can potentially control ephemeral weed infestation,which is a great challenge in various plant production systems of the Gulf Region.The results of the present study suggest that the impact of soil amendment on the WUE of exotic plants is marginal and might not be economically justified.Replacing exotic with native ornamental plant species seems to have a far greater water-saving potential than the amendment of the soil,while weeds can be suppressed in the absence of topsoil moisture.

Industrial Structure and Competitive Strength of 31 Provincial Districts——A GIS-based Dynamic Shift-Share Analysis

By using the dynamic shift-share analysis, the industrial structure and competitive strength of 31 provincial districts except Taiwan, Hong Kong and Macao are studied by taking the GDP of the three industries as the research entrance and the whole nation as the reference district. The industrial structure and competitive strength of each provincial district is measured. Through the analysis of pertinence, the correlation degree of industrial structure and industrial competitive strength to economic growth is analyzed. The results show that the industrial competitive strength is closely related to the economic growth of the 31 provincial districts, but the contribution made by the industrial structure to economic growth is insufficient and the effect of industrial structure does not match with that of industrial competitive strength. According to industrial competitiveness and industrial structure effect, 31 provincial districts of the whole nation are divided into 4 types and the relevant countermeasures of the four types are put forward.

COMPETITION BUILDS STRENGTH IN FINANCIAL MARKETS

Transitioning from a“planned”economy to a“market”economy may be a long and arduous task for China,but opening its financial markets to foreign competition will help build stability and strength for the Chinese economy, says U.S.Ambassador Alan Holmer.Holmer,who was recently named as Special Envoy for China and for the Strategic Economic Dialogue,answered written questions by Beijing Review on his views of the economic relationship between China and the United States and the reforms he sees as vital to a good bilateral relationship.

Structure of National Science and Technology Competitiveness: A Methodological and Empirical Study

This paper clearly defines the concepts of the national competitiveness,the national S&T competitiveness,and the national S&T competitiveness structure.It develops an evaluation framework with three dimensions:the national S&T competitive potential,the national S&T competitive strength and the national S&T competitive effectiveness.This paper proposes a structure analysis method and depicts the national S&T competitiveness structure of 35 countries in an empirical research.Apart from the definitions and the structure analysis method,this paper mainly draws the following conclusions:(1)In the one-dimensional national S&T competitiveness structure,the top 5 countries were all developed countries in 2015,while the developing countries generally performed better than developed countries considering the average annual growth rate of the national S&T competitiveness index.The 35 countries are clustered into 4 categories using the two-dimensional structure analysis method.For example,based on the ranking of the national S&T competitive strength index and the national S&T competitive effectiveness index of the 35 countries in 2015,the 35 countries are clustered into four categories:high-strength and higheffectiveness,low-strength and high-effectiveness,low-strength and low-effectiveness,and high-strength and low-effectiveness.(2)To a large extent,there is a significant correlation between the national S&T competitiveness index score and the GDP per capita value.And to a certain extent,there is some correlation between the national S&T competitiveness index score and the GDP value.Moreover,under the background of strength and effectiveness combination,or under the background of strength and potential combination,the national S&T competitiveness structure and GDP or GDP per capita show significant relationship.