彩叶植物在森林公园规划设计中的应用研究——以淮安白马湖森林公园为例

本文以淮安白马湖森林公园为研究对象,基于对公园的现状调研和发展目标提出"彩色森林公园"的定位,其规划设计的核心是通过彩叶植物的配置和应用,对森林公园进行林相和环境的改造,从而营造富有特色的彩叶风景林和滨水群落。本文详细介绍了彩叶植物在森林公园规划设计中的基本原则、规划分区应用、典型配置模式和注意事项等方面的内容,以期为今后的彩叶植物在风景园林中的应用提供参考和借鉴。     

A conceptual model of riparian forest restoration for natural flood management

There is an increasing emphasis on using natural processes, including riparian forest restoration, to enhance the ecological, hydrological and geomorphological functioning of watercourses. However, we have insufficient knowledge on how the supply and retention of in‐channel wood from riparian forest stands changes with age, with inferences typically based on data from terrestrial forests. This presents a challenge in estimating the efficacy and functional lifespan of restoration projects. In this paper, we use a riparian forest growth model to show there is a lag of up to 40–50 years between the start of forest growth and trees delivering wood to the channel that is large enough to resist fluvial transport, anchor logjams and so increase channel complexity and hydraulic resistance. Resource managers need to account for realistic timescales over which changes promoted by riparian woodland restoration will occur and may need to consider using interim engineered logjams as the forest develops.     

Foraging for identity: the relationships between landscape activities and landscape identity after catastrophic landscape change

ABSTRACT

In this article, we deal with landscape activities in relation to changing landscape identity after a major wildfire in Sweden in 2014. The aim was to investigate the relationships between 22 landscape activities (before the fire) and 2 components (emotion and cognition) of landscape identity (before and after the fire). A total of 656 respondents living nearby the fire area participated in this study. Before the fire, a positive association was found between the activities of enjoying nature and foraging, and both components of landscape identity. This suggests that the more participants enjoyed nature and picked berries and mushrooms, the stronger their attachment to the landscape (emotion), and the more they remembered and reasoned about the landscape (cognition). Post fire, these relationships were found only between the two components of landscape identity and foraging. This implies a significant role of this type of activity for keeping ‘alive’ landscape identity.     

Pipe failure rate prediction in water distribution networks using multivariate adaptive regression splines and random forest techniques

ABSTRACT

This paper presents the results of a comparison between multivariate adaptive regression splines (MARS) and random forest (RF) techniques in pipe failure prediction in two water distribution networks. In this regard, pipe diameter, pipe length, pipe installation depth, pipe age and average hydraulic pressure are considered as input variables. Results show that the RF outperforms the MARS which is found as an accurate pipe failure rate predictor. The proposed models are further evaluated through dividing the data into three parts of lower, medium and higher pipe failure rate values. According to the equations produced by MARS technique, three variables of pipe diameter, pipe age and average hydraulic pressure are distinguished as the most effective variables in predicting pipe failure rate in the first case study. Four variables of pipe diameter, pipe length, pipe age and average hydraulic pressure are determined as the most effective variables in the second case study.     

Architecture of underground spaces: From isolated innovations to connected urbanism

This article provides an introduction to an architectural approach of subterranean space, presenting its properties and principles of development. It then analyzes some subsurface experiences of the 20th century and, by looking at their successes and failures, shows how a renewed human and dynamic vision could help move from developing isolated structures towards a connected form of urbanism. Such a transition would provide an adequate response to the challenges of modern metropolises, for instance in the Paris area. On the strength of these realizations, a national transdisciplinary research program was deemed necessary and this is how Ville 10D – Ville d’Idées came to be in 2013. This article thus recaps the history and reflection that led to the creation of the Ville 10D project, and explains how it emerged as a systemic approach to subterranean development.MethodConception and development of a change of paradigm: consider the living and motion as primary, unifying agents between the underground and the city above it; play with and act on the subsurface in order to reinject mixed uses and complexity into the city through a systemic approach of the underground in the urban eco-system.Creation of a research project whose organization reflects these concerns: in order to take the living into account, make the study as cross-disciplinary as possible, mixing competences and points of views.Four-fold organization – socio-economical, environmental, psycho-social, cognitive (knowledge and management of the underground) – corresponding to four main themes plus two transversal themes (legal and urban planning). Unfolding in four stages of 18 months each, these thematic approaches are casting converging light onto token sites chosen for their diverse typology. Around a hundred professional players are involved in the Ville 10D project.Study resultsBeyond the data gradually obtained through the project studies themselves, and without anticipating those to come, the first results so far have shown a growing awareness of and interest in the reality of underground potential. There has been a genuine gradual involvement of the development players, researchers and academics in elaborating the project.For us, gaining support from the players is an essential stake to “unlock” the underground in the minds first, then in reality thanks to tools built by Ville 10D in all the fields of development.ConclusionResearch reports are issued upon completion of each of the stages and posted on the website http://www.ville10d.fr. We are planning to present and publish the final reports at an international colloquium in 2017.     

重庆主城区森林城市建设规划初探

对重庆山地自然条件和环境状况进行了分析,概括性地提出了重庆主城区森林城市建设六大工程,对重庆森林城市建设规划进行了初步的探讨,从而解决了重庆市建设森林城市所面临的差距与问题。     

System reliability analysis for mixed uncertain variables

Uncertainties in a physical system should be modeled accurately to obtain an accurate estimate of its safety. Based on the amount and type of information available, either probability theory or possibility theory can be used. In probability theory variation in the parameters is modeled using probability density functions and in possibility theory it is modeled using fuzzy membership functions. But when dealing with a combination of both probability distributions and fuzzy membership functions, the computational cost involved in estimating the bounds of reliability increases exponentially because one reliability analysis, which is a computationally expensive procedure, is performed at each possibility level. Moreover, the failure of structural systems is governed by multiple limit-state functions, all of which are to be taken into consideration for determining its safety. These limit-state functions are often correlated and the accuracy of the estimated system reliability is dependent on the ability to model the joint failure surface. To reduce the computational cost involved without loss of accuracy, high quality function approximations for each of the limit-states and the joint failure surface are developed in this paper. Numerical examples are presented to demonstrate the efficiency and accuracy of the proposed methodology.     

Effect of admicellar properties on adsolubilization: column studies and solute transport

Mixtures of anionic and cationic surfactants exhibit synergistic behavior as evidenced by low critical micelle concentrations (CMC) of the mixed system, increased surface activity, and improved detergency performance. The adsorption of a single-head anionic surfactant, sodium dodecyl sulfate (SDS), in mixture with a twin-head cationic surfactant, pentamethyl-octadecyl-1,3-propane diammonium dichloride (PODD), showed synergism of adsorption onto silica when present at a mixing ratio of 1:3 (cationic-rich), and also demonstrated lower surfactant desorption with water flushing of columns packed with the surfactant-modified media. In addition, the proportion of the mixed surfactants in the admicelles moved from the initial ratio of 1:3 towards equimolar after rinsing the surfactant-modified silica absorbent. The retardation of organic solutes passing through columns packed with modified-silica adsorbent increased nominally three fold for silica modified with mixed surfactants versus single surfactants (retardation factors increase from 4.0 to 12.8 for styrene and from 32.1 to 90.2 for ethylcyclohexane for single and mixed surfactants, respectively). Thus, this study demonstrates that mixed surfactant systems more effectively modified the silica surface than single surfactant systems both in terms of enhanced retardation of organic solutes and in terms of reduced surfactant desorption.     

Effects of ultrasound on suspended particles in municipal wastewater

The objective of this research is to explore the fundamental characteristics of how particles in wastewater respond to ultrasound, with an aim to improve wastewater disinfection. Particles of a predetermined size fraction and concentration were treated with varying doses of ultrasound at 20.3 kHz. Ultrasonic power transfer to the fluid was measured using calorimetry or acoustical measurements. Image analysis particle counting was used to measure the size distribution of particles before and after ultrasound treatment. The influence of three parameters: particle origin (raw wastewater or from the aeration basin of the activated sludge process), particle concentration, and particle size on the percentage of particle breakage after ultrasound treatment was compared. It was found that raw wastewater and aeration basin particles of the same size fraction (90-106 μm) responded to ultrasound in a similar way. Particle breakage was not affected by changes in particle concentration from 100 to 400 particles per mL. Larger wastewater particles (90-250 μm) were more susceptible to breakage than smaller ones (38-63 μm diameter). The percentage of particle breakage increased linearly with a logarithmic increase in the ultrasound energy density, that is the ultrasound energy delivered per unit volume of the sample (R² = 0.48-0.91). An expression that predicts the percent of particles broken as a function of ultrasound energy density is provided.     

Deforestation and greenhouse gas emissions associated with fuelwood consumption of the brick making industry in Sudan

The study focuses on the role of the fired clay brick making industry (BMI) on deforestation and greenhouse gas (GHG) emissions in Sudan. The BMI is based on numerous kilns that use biomass fuel, mainly wood which is largely harvested unsustainably. This results in potential deforestation and land degradation. Fuelwood consumption data was collected using interviews and questionnaires from 25 BMI enterprises in three administrative regions, namely Khartoum, Kassala and Gezira. Annual fuelwood consumption data (t dm yr^− 1) was converted into harvested biomass (m³) using a wood density value of 0.65 t dm m^− 3. For annual GHG estimations, the methodological approach outlined by the Intergovernmental Panel on Climate Change (IPCC) was used. According to our results, the annual deforestation associated with the BMI for the whole of Sudan is 508.4 × 10³ m³ of wood biomass, including 267.6 × 10³ m³ round wood and 240.8 × 10³ m³ branches and small trees. Total GHG emissions from the Sudanese BMI are estimated at 378 028 t CO₂, 15 554 t CO, 1778 t CH₄, 442 t NO_X, 288 t NO and 12 t N₂O per annum. The combined CO₂-equivalent (global warming potential for 100-year time horizon) of the GHG emissions (excluding NO_X and NO) is 455 666 t yr^− 1. While these emissions form only a small part of Sudan's total GHG emissions, the associated deforestation and land degradation is of concern and effort should be made for greater use of sustainable forest resources and management.