Cadmium accumulation characteristics of floricultural plant Cosmos bipinnata*

The artificially high soil cadmium (Cd) concentration screening method was used to screen Cd-hyperaccumulators from floricultural plants. Among the five species of floricultural plants screened, Cosmos bipinnata showed the characteristics of Cd-accumulators. A pot experiment was conducted to further study Cd accumulation characteristics of C. bipinnata. The results showed that the biomass, chlorophyll content, superoxide dismutase activity, peroxidase activity and soluble protein content of C. bipinnata first increased and later decreased with the increase in soil Cd concentration, but the carotenoid content and catalase activity of C. bipinnata reduced. Cd contents in roots, stems, leaves and shoots of C. bipinnata increased with increasing soil Cd concentration. When the soil Cd concentration was 50?mg?kg^?1, the Cd content in shoots was up to 112.62?mg?kg^?1, which was higher than the Cd-hyperaccumulator critical value. The root and shoot bioconcentration factors exceeded 1 in various Cd treatments, but the translocation factors were less than 1. When the soil Cd concentration was 50?mg?kg^?1, the Cd accumulation in shoots achieved the maximum of 224.30?μg plant^?1. Therefore, considering the tolerance and accumulation of Cd, C. bipinnata is a Cd-accumulator that could be used to remediate Cd-contaminated urban soil.     

集中供热工程实施前后大气环境影响对比分析研究

采暖期的大气环境质量与供热方式息息相关,集中供热是提高我国环境空气质量的一种可行办法。以定西市临洮县集中供热项目为例,结合拟建项目的建设特点,利用环评软件——AERMOD预测模式分析实施集中供热工程前后以大气为主的环境影响的差异,用以说明集中供热工程的实施具有巨大的环境效益。分析表明:集中供热减少了SO2、NO X烟尘的排放量,对环境的改善将起到良好的作用。     

Theoretical and Empirical Analysis on Influence Factors of Modern Agricultural Equipment Level in the Processof Agricultural Sustainable Development

To promote modern agricultural equipment level is one characteristic of constructing and developing modern agriculture in China.This paper makes up stepwise linear regression analysis model of influence factors of modern agricultural equipment level,and chooses rural labor,per capita income of rural residents,rural investment,proportion of people at secondary education level and at higher level in per hundred rural labor force and arable land area as independent variables,and total power of machine as induced variable.The major results show that the relativity of modern agricultural equipment level,rural investment and education level of peasants is remarkable,and they are the major influence factors of modern agricultural equipment level.Raising investment level of rural infrastructure construction as well as and research and development and promotion of advanced and applicable modern agricultural equipment,improving quality and education level of peasants can accelerate the development of China’s modern agricultural equipment effectively in the process of agricultural sustainable development.     

The drivers of risk to water security in Shanghai

Big cities are often said to have big water problems, and Shanghai is no exception. In this paper, we examine and compare the influence of the major factors that give rise to the risk of water insecurity in Shanghai. There is an extensive and diverse literature on these issues, dealt with in isolation, and here, we provide a synthesis of the literature, together with our own assessments and calculations, to assess what are the risks to Shanghai’s water supply and what is our degree of confidence in this assessment. We describe the systems that supply water to the city, and past and future changes in the systems, including changes in the glaciers that supply some water to the river, changes in climate, changes in land use, the construction of dams, and water diversions. We show how, at the same time as Shanghai is increasing its dependence on the Yangtze river, water diversions and sea level rise are increasing the risk that this water will be too saline to consume at certain times of the year. This analysis suggests that most of the major drivers of the risk to water security in Shanghai are within the power of environmental managers to control.     

Dynamics of the buoyant plume off the Pearl River Estuary in summer

Field measurements of salinity, wind and river discharge and numerical simulations of hydrodynamics from 1978 to 1984 are used to investigate the dynamics of the buoyant plume off the Pearl River Estuary (PRE), China during summer. The studies have shown that there are four major horizontal buoyant plume types in summer: Offshore Bulge Spreading (Type I), West Alongshore Spreading (Type II), East Offshore Spreading (Type III), and Symmetrical Alongshore Spreading (Type IV). River mouth conditions, winds and ambient coastal currents have inter-influences to the transport processes of the buoyant plume. It is found that all of the four types are surface-advected plumes by analysing the vertical characteristic of the plumes, and the monthly variations of the river discharge affect the plume size dominantly. The correlation coefficient between the PRE plume size and the river discharge reaches 0.85 during the high river discharge season. A wind strength index has been introduced to examine the wind effect. It is confirmed that winds play a significant role in forming the plume morphology. The alongshore wind stress and the coastal currents determine the alongshore plume spreading. The impact of the ambient currents such as Dongsha Current and South China Sea (SCS) Warm Current on the plume off the shelf has also assessed. The present study has demonstrated that both the river discharge and wind conditions affect the plume evolution.     

Reduction of Fusarium rot and maintenance of fruit quality in melon using eco-friendly hot water treatment

Significant losses in harvested fruit can be directly attributable to decay fungi and quality deterioration. Hot water treatment (HWT) has been demonstrated to be an effective and economic environment-friendly approach for managing postharvest decay and maintaining fruit quality. In this study, the effects of HWT (45 °C for 10, 15, 20, and 25 min) on in vitro growth of Fusarium oxysporum, in vivo Fusarium rot, and natural decay of melon were investigated. HWT inhibited spore germination and germ tube elongation of F. oxysporum. Protein impairment and ATP consumption triggered by HWT contributed to the inhibitory effect. Results of in vivo studies showed that HWT effectively controlled Fusarium rot and natural decay of melon. Correspondingly, HWT induced a significant increase in content of total phenolic compounds and lignin of melon. These findings indicate that the effects of HWT on Fusarium rot may be associated with the direct fungal inhibition and the elicitation of defense responses in fruit. Importantly, HWT used in this study had beneficial effects on fruit quality as well. HWT may represent an effective non-chemical approach for management of postharvest Fusarium rot.     

Water Governance and Water Use Efficiency: The Five Principles of WUA Management and Performance in China1

Wang, Jinxia, Jikun Huang, Lijuan Zhang, Qiuqiong Huang, and Scott Rozelle, 2010. Water Governance and Water Use Efficiency: The Five Principles of WUA Management and Performance in China. Journal of the American Water Resources Association (JAWRA) 46(4): 665-685. DOI: 10.1111/j.1752-1688.2010.00439.x Abstract: In recent years China has attempted to reform water management by decentralizing water management responsibilities. The overall goal of our paper is to better understand the emergence of water user associations (WUAs) in China and assess if they are adhering to the practices spelled out by the Five Principles, a set of recommended practices that are supposed to lead to successful WUA operation. Using four sets of different types of villages to examine implementation and performance, we find that World Bank-supported WUA villages (“Bank villages”) can be thought of as operating mostly according to the Five Principles. For example, the Bank villages were endowed with a more reliable water supply; were set up and were operating with a relatively high degree of farmer participation; and leaders were more consultative and the process more formal. When WUAs are run according to the Five Principals, we show that WUAs increase water use efficiency. The study also provides evidence that there is a perception in the Bank villages that water management is improving in general and that there is less conflict both within the village and among villages. Perhaps more importantly, we find that the Bank’s effort to promote WUAs extended beyond their own project villages. The openness, consultative nature, and transparency found in the Bank WUAs are also found (albeit at a somewhat lower level) in the non-Bank WUA villages.     

Quantitative analysis of CO2 embodiment in international trade: An overview of emerging literatures

The increasing volume of CO₂ embodiment in international trade adds a layer of complexity to environmental policies and has raised arguments on the traditional production based responsibility for CO₂ emissions. In order to help understand the quantity of CO₂ embodiment in trade and its policy implications, this paper gives observations to recently emerging literatures that quantitatively discuss CO₂ embodiment in trade. The analytical approaches share the principle of using input and output modeling but vary dramatically in study boundary and estimation accuracy. The calculations can be roughly categorized into three types: direct quantification of CO₂ embodiments in multiregional trade, direct quantification of CO₂ embodiment in bilateral trade, and indirect analysis by comparing the scenarios with or without trade. The practical estimations strongly rely on trade partner selection and data availability. An obvious imbalance of net CO₂ embodiment in the commodity trade between major developed countries and developing economies as a whole was confirmed by these literatures. Carbon taxes and other possible limitations on CO₂ emissions have been addressed. The consistency across the calculations could be enhanced by systematic analyses in more detail to convince the international community to take binding commitments for the reduction of global CO₂ emissions.     

Willingness and behavior towards e-waste recycling for residents in Beijing city,China

This paper is to investigate the behavior of residents towards electrical and electronic waste (e-waste) recycling in Beijing. For this purpose a large sample questionnaire survey was performed to explore the residents’ characteristics of recycling behavior and preference of e-waste recycling pattern. Besides, the willingness of residents to participate in e-waste recycling was also assessed in our study. For this a logistic regression model was developed to estimate and explain residents’ willingness in e-waste recycling. The model showed that Convenience of recycling facilities and service, Residential conditions, Recycling habit and Economic benefits are four determinants of Beijing residents’ willingness and behavior in e-waste recycling. And centralized recycling pattern by professional recovery spots would have a broad prospect if various kinds of channels can be provided to make the residents feel more convenient in e-waste recycling.