人地关系的危机和性质及协调思维

人地关系危机的本因是人类意识和社会经济行为与其生存环境的潜在利用方向、可承载量之间存在的巨大不整合和全面失衡,其核心是资源问题。人地关系的性质是多种人地关系因子共同作用的区间对应的函数关系。人类应当采取“多管齐下、本标兼治”的协调战略,树立资源中心论观念,着力于改善资源利用结构和效率,改进人地关系的关联方式和复合作用效应,建立多层次的人地协调工程,推动人与自然的根本和解和全面合作,最终实现两者的整体同一化和共生协调化。人与自然的关系是人类思考和认识的永恒主题。目前,人地关系呈现出历史性和全球性的危机,已成为人类生存和发展的根本障碍。探讨危机产生的根源,研究人地关系的性质,并从中确定调控人地关系的基本思维和方式,无疑具有重大的现实意义和理论价值。     

Regime shifts and resilience in China’s coastal ecosystems

Regime shift often results in large, abrupt, and persistent changes in the provision of ecosystem services and can therefore have significant impacts on human wellbeing. Understanding regime shifts has profound implications for ecosystem recovery and management. China’s coastal ecosystems have experienced substantial deterioration within the past decades, at a scale and speed the world has never seen before. Yet, information about this coastal ecosystem change from a dynamics perspective is quite limited. In this review, I synthesize existing information on coastal ecosystem regime shifts in China and discuss their interactions and cascading effects. The accumulation of regime shifts in China’s coastal ecosystems suggests that the desired system resilience has been profoundly eroded, increasing the potential of abrupt shifts to undesirable states at a larger scale, especially given multiple escalating pressures. Policy and management strategies need to incorporate resilience approaches in order to cope with future challenges and avoid major losses in China’s coastal ecosystem services.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0692-2) contains supplementary material, which is available to authorized users.     

Study on a new correlation between diffusion coefficient and temperature in porous building materials

The diffusion coefficient (D) and partition coefficient (K_ma) are the two important parameters used to predict the volatile organic compound (VOC) emission or sorption characteristics in porous building materials. D and K_ma may be strongly affected by temperature (T). In this study, we derived a new correlation between D and T based on the assumption that molecular diffusion is dominant, and evaluated this correlation using a series of existing experimental data. The modeling results using the new correlation agree well with the experimental data. The correlation would be useful for assessment of indoor air quality under different environmental (temperature) conditions.     

Study on Biodegradable Starch/OMMT Nanocomposites for Packaging Applications

The thermoplastic starch (TPS) and nanocomposite(TPS/OMMT) was prepared with 15% carbamide, 15% ethanolamine and different contents of organic activated montmorillonite (OMMT) by twin-screw extruder with a 130 °C barrel temperature. Fourier transforms infrared spectroscopy and wide angle X-ray diffraction shown that the alkylamine in dodecyl benzyl dimethyl ammonium bromide could react with MMT via cation exchange reaction. After treated, the d(001)space distance of MMT increased from 1.5 to 1.7 nm. Scanning electron microscope revealed that the lower contents of OMMT could disperse well in the matrixes of TPS. The carbamide, ethanolamine and the OMMT could destroy the crystallization behavior of starch, but only the OMMT restrained this behavior for long-term storing. Mechanical properties investigation indicated that the tensile strength and modulus of TPS/OMMT nanocomposites were better than those of TPS, while the elongation at break was descended with the increasing of OMMT contents. When the content of OMMT was 4%, the tensile strength and modulus of TPS was improved from 4.2 and 42 MPa to 6.0 and 76 MPa, respectively.     

基于响应绩效的重大事故应急预案编制技术研究

重大事故应急预案是保证企业应急救援工作快速、高效地开展的关键。应急预案的响应绩效是预案对于预防事故发生和控制事故恶化的实际效果,基于响应绩效的重大事故应急预案编制方法就是将绩效作为核心的思想融入编制的各环节。围绕预案的编制原则、文件要素和编制流程对方法进行介绍,并进一步详细阐述了基于响应绩效的预案编制要点,从而保证预案的完整性、逻辑性、可操作性和指导性四方面的响应绩效要求。     

盐生植物种子萌发的特点及其生理基础

用NaCl和等渗PEG处理8种盐生植物和2种非盐生植物种子。结果表明：NaCl和等渗PEG对所有种子的萌发率都产生抑制作用,而且PEG（对盐生植物）的抑制程度大于等渗NaCl,NaCl对盐生植物萌发的抑制水平随处理时间延长而降低,但对非盐生植物种子萌发率的抑制程度增大到8d以后即不再增大。另外,在0．6MPaNaCl下,随处理时间延长,盐地碱蓬和琐琐种子的α－淀粉酶活性不断提高,SOD活性基本不变,但小麦和大麦种子的α－淀粉酶活性在处理8d后接近最大值,SOD活性显著下降,这些结果说明,影响盐生植物种子萌发率的因素与渗透胁迫,种子内部一些关键酶的活性及萌发过程中大量吸收和积累盐离子等都有关系。图6参19     

Reproduction in a simultaneous hermaphroditic shrimp, Lysmata wurdemanni: any two will do?

The caridean shrimp Lysmata wurdemanni (Gibbes) displays protandric simultaneous hermaphroditism with out-crossing, but not all males become simultaneous hermaphrodites (euhermaphrodites). In this laboratory study, we attempted to determine why some shrimp remain males. In our experiment, we grew L. wurdemanni from postlarvae to adults in several group sizes and observed their reproductive function. We found that all shrimp reared in isolation become euhermaphrodites. When cultured in a group, the proportion of shrimp remaining male decreased with increasing group size. Except for those that mated within a day, inter-molt euhermaphrodite-phase shrimp (with or without embryos) and inter-molt male-phase shrimp fertilized eggs successfully. On the other hand, euhermaphrodite shrimp can only mate as females and have their eggs fertilized during a narrow post-molt window (less than 12 h) in each molt cycle (10 days). The fertilization rate of male-euhermaphrodite pairs was similar to that of euhermaphrodite-euhermaphrodite pairs. There are at least two non-exclusive explanations for the persistence of male shrimp in a group. In certain group compositions, an individual may gain more reproductive fitness as a large male with multiple mating partners than as a small female with low clutch size. Alternatively, the presence of male-phase individuals, with variable molt-cycle duration (5-8 days), may be necessary to ensure mating. This study is the first direct experimental demonstration of social control of sex change in the decapod crustaceans.     

Aerobic treatment of swine manure to enhance anaerobic digestion and microalgal cultivation

Aerobic treatment of swine manure was coupled with anaerobic digestion and microalgal cultivation. A 14-day aerobic treatment reduced the total solid content of swine manure by >15%. Ammonia and carbon dioxide were stripped by the air supplied, and this off-gas was further used to aerate the culture of Chlorella vulgaris. The microalgal growth rates in Bristol medium and the wastewater with the off-gas increased from 0.08 to 0.22 g/L/d and from 0.15 to 0.24 g/L/d, respectively. Meanwhile, the aerobically treated swine manure showed a higher methane yield during anaerobic digestion. The experimental results were used to establish a demonstration unit consisting of a 100 L composter, a 200 L anaerobic digester, a 60 L tubular photobioreactor, and a 300 L micro-open raceway pond.     

O／W型乳化液的处理

采用药剂破乳－电解破乳工艺处理Ｏ／Ｗ型乳化液，药剂破乳选用聚合硫酸铁为破乳剂，破乳时最佳ＰＨ为８，聚合硫酸铁的最佳投量为１５００ｍｇ／Ｌ，电解破乳选用铁作阳极，铝作阴极，电流密度０．８６Ａ／ｄｍ＾２，极距２５ｍｍ，电解时间３ｈ。在上述条件下，破乳效果良好，出水清澈透明，ＣＯＤ总去除率可达到９６－９７％。