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The potential of 32 frequently studied ornamental and/or energy grasses and two cadmium/zinc hyperaccumulators for phytoextraction and phytostabilization was compared by their growth in a historically contaminated soil over a three-month pot experiment. Shoot and root biomasses varied by factors of 14.2 and 62.7, respectively. Mainly due to their large biomass, Napier grass (Pennisetum purpureum ‘Purple’) and variegated giant reed (Arundo donax var. versicolor) accumulated cadmium and zinc contents in shoots up to 109.3% and 55.4% higher, respectively, than those in the cadmium/zinc hyperaccumulators, despite their lower metal concentrations. Pennisetum purpureum ‘Purple’ accumulated the most zinc and the third highest cadmium in roots. Bioconcentration factors of cadmium in roots were greater than 1 for 19 grasses. The present study demonstrated that many of these grasses may be suitable for phytostabilization of soil cadmium. Arundo donax var. versicolor exhibited the most potential for phytoextraction of soil zinc, whereas Pennisetum purpureum ‘Purple’ was best for phytoextraction and phytostabilization of cadmium and phytostabilization of zinc. Ornamental/energy grasses may have greater potentials for soil remediation than hyperaccumulators, especially given their utility and eco-economic benefits. The considerable variation in their performance emphases the value of screening to select the most effective candidates.

Pennisetum grasses (P. purpureum Schumach. ‘Purple’, P. alopecuroides (L.) Spreng. ‘Liren’ and P. alopecuroides (L.) Spreng. ‘Changsui’), and a cadmium (Cd) hyperaccumulator (Thlaspi caerulescens J.Presl & C.Presl), were grown in soil with four Cd addition levels of 0, 2, 20 and 200 mg/kg. Toxicity symptoms were not observed although growth of all plants decreased as Cd addition increased. Shoot bioconcentration factor (BCFS), the translocation factor (TF) and shoot accumulation of Cd for most plants first increased and then declined as Cd concentrations increased. In contrast, the root bioconcentration factor (BCFR) for T. caerulescens declined and root Cd accumulation for T. caerulescens and two P. alopecuroides cultivars increased consistently as Cd levels increased. P. purpureum had the largest biomass with shoot Cd accumulation similar to that of T. caerulescens, despite lower foliar Cd concentration. Although shoot Cd concentrations of two P. alopecuroides cultivars were lower than for P. purpureum, root Cd concentrations were greater. P. purpureum had Cd BCFS and TF (> 1) at 2- and 20-mg/kg Cd addition treatments, similar to T. caerulescens. P. alopecuroides cultivars had Cd BCFR (> 1) and TF (< 1) at all Cd levels. Roots did not affect rhizosphere pH. However, concentrations of acid extractable Cd in rhizosphere soil were lower than those of corresponding non-rhizosphere soil at all Cd levels for T. caerulescens and P. purpureum; T. caerulescens and P. purpureum did not affect less bioavailable Cd fractions. Concentrations of acid extractable Cd in the rhizosphere of the P. alopecuroides cultivars were not reduced at any Cd level. Differences in Cd accumulation among the three Pennisetum grasses were mainly attributable to root biomass and Cd TFs rather than rhizosphere Cd mobility.

This paper discuss the resource efficiency evaluation in complex network system. By using network DEA theory, we proposes a network DEA model that embodies the internal network structure for complex production efficiency evaluation. A sufficient condition for a complex production to be input efficient is discussed. Furthermore, by using the network DEA model, we investigate the internal resource waste in complex production from two different situations. One is the intermediate resource waste that called visible internal resource waste, and another is invisible internal resource waste. Examples shows that to improve the technical efficient of the production may increase its internal resource waste in complex network production1

Using multi temporal satellite images of remote sensing,wetland information was extracted by decision tree classification method combined with field surveying and four Lake Dongting's wetland type distribution maps were drawn out.This paper mainly analyzes the dynamic characteristics of wetland vegetation,driving factors and their influence on the wetland ecosystem in this region.Results show that vegetation community distribution and proportion changed obviously.In the past 17 a,forest area increased by 367.88 km2 at a rate of 1127.51%.The forest area extended to main part of beaches and became the main vegetation type of Lake Dongting.Reed area decreased by 44.09 km2,while sedge land area increased by 2.99 km2,with change rate of-5.80% and 0.40%,respectively.This change resulted from both natural environment evolution and human activities.The destruction of natural wetland vegetation,especially planted reed and poplar,destroyed the structure and function of Lake Dongting wetland ecosystem.In order to protect the Lake Dongting wetland effectively,we must rationally exploit bottomland resource,protect natural wetland vegetation and make good management on shoal forestation.

Finite-element analysis method is used to make numerical analysis of fins with an excessive width and the unfavorable consequences are directly displayed in this paper. Compensation measures are proposed to increase the fin thickness or the thickness of fin root. Besides, the results of numerical analysis and compensation effect of the measures are provided for further discussion.

Researchers and decision makers paid close attention to cycled agriculture,but few studied quantitatively with the point of industry economy.The aim of this paper is to evaluate an agricultural circulation system as a case study using the emergy accounting method.This agricultural circulation system consists of three subsystems: agro-planting subsystem,cow-breeding subsystem and mushroom cultivation subsystem.Results showed that cow-breeding subsystem and mushroom cultivation subsystem use large amounts of purchased resources and have lower emergy yield ratio and also have higher investment ratio and environmental loading ratio,it means that these subsystems had depended on the outer inputs and their sustainability is very low.Actually,both of the two subsystems are economically profitable in the case that they are syncretic with each other and with planting subsystem by affording the original materials and disposaling the wastes.The emergy investment ratio and environmental loading ratio of the circulation system is lower than the subsystems.it indicated that the agro-circulation system decreased the dependence on the outer economical inputs and natural resources,and can compensate the used resources.Furthermore,the emergy yield ratio and emergy sustainable indices of the agro-circulation system is relatively higher than the separate subsystems,which demonstrated that this model can ensure higher economic profits.The government should encourage this model and provide so quantitative subsidies to the farmers and managers who takes this model.

An ecological energetic evaluation is presented in this paper for the dairy-mushroom system in Beijing Miyun reservoir catchment in the year 2010. It developed a system diagram for the dairy and mushroom productions based on Odum’s unified measure. Conventional systems indices of the emergy yield ratio (EYR), emergy investment ratio(EIR), environmental load ratio(ELR) and environmental sustainability index(ESI) are introduced for congregated systems ecological assessment. The overall diary-mushroom system is shown with outstanding production competence compared with other agricultural systems in other regions. The mushroom subsystem is highly benefited from the cow subsystem by making use of cow excrements as materials, which can alleviate pollution caused by excessive piles up of cow manure and rain washing down to the groundwater. Compared with the subsystems, diary-mushroom agrocirculation system has higher yield raio, lower emergy investment ratio (EIR), and higher environmental sustainable index (ESI) value. In the long run, processes with a lower percent of purchased emergy are likely to be more sustainable, of which corn plantation, cow breeding and mushroom cultivation are not aparted and formed into a circulation chain. So the dariymushroom circulation system is one of a sustainable agricultural mode adapted for this water protection area and should be promoted. Keywords-emergy evaluation; diary-mushroom system; beijing miyun reservoir catchment.

Based on the Lie group theory, the one-parameter Lie group admitted by a Silnikov equation is studied. The result reveals that the Silnikov equation accepts no global analytical non-trivial one-parameter Lie group. In this sense, the Silnikov equation is not integrable in quadrature.

The travelling wave solutions for Kdv-Burgers-Kuramoto equation are considered. the nonexistence of first integrals of traveling wave solutions equation of Kdv-Burgers-Kuramoto equation is shown. therefore, a sufficient condition of nonexistence of travelling wave solutions of Kdv-Burgers-Kuramoto equation is given. two independent one-parameter lie groups admitted by travelling wave solutions equation of Kdv-Burgers-Kuramoto equation are obtained.

The aim of this paper is to evaluate the agro-planting subsystem and mushroom cultivation subsystem and both the two's circulation system of a case study in Beijing Miyun water protective area using the emergy accounting methodology. The main findings of this work were that the agro-planting stage uses the highest amount of resources and has lower emergy yield rate (EYR) and emergy loading rate(ELR), the mushroom stage has higher EYR, is a more effective method to increase economic output using more non-renewable resources and purchased resources, but its environmental loading ratio is very high which means its sustainability is low. Actually, mushroom production is economically profitable and sustainable only when the system is syncretic with the planting system by affording the original materials of which is a circulation system. The circulation system's emergy yield rate(EYR) and emergy sustainability index(ESI) is comparative high than the two subsystems. Result demonstrate that extending the planting system chain to produce mushroom using planting wastes is one important method that can ensure higher economic profit and lower environment stress, the government should encourage this mode and provide so quantitative subsidies to the farmers and managers who takes this mode.

The classical gyroscope system (Euler-Poisson equations) is an important mechanics system, which describes the motion of a heavy rigid body moving around a fixed point. In this paper, the stability of an equilibrium state of gyroscope system is studied by using the energy-Casimir function method. The stability of a class of dynamics of gyroscope system is obtained.