竞争条件下光照对两种淡水藻生长的影响

研究了铜绿微囊藻与斜生栅藻在单种和三种配比(10:1、1:1、1:10)共同培养条件下,不同的光照强度对其生长的影响,计算了不同培养体系中两种藻的磷吸收半饱和常数。结果表明:单独培养时,铜绿微囊藻在3000lx获得最大增长率,而斜生栅藻在5000lx时增值最快;共同培养时,两种藻的生长速率相对单独培养条件下均有不同程度的下降,两种藻之间存在着互相的竞争抑制作用;在10:1共培养条件下,栅藻对微囊藻的抑制作用超过了微囊藻对栅藻的抑制作用;在1:1和1:10共培养条件下,光强低于6600lx时,微囊藻对栅藻的抑制作用相对于栅藻对微囊藻的抑制作用更大。从光吸收半饱和常数看,微囊藻的光吸收的半饱和常数总是小于栅藻,可见微囊藻对光更具亲和性。总体上看,较低光照下,微囊藻的竞争能力强于栅藻,微囊藻竞争成为优势种具有较高的概率;而光照强度较大时,栅藻竞争成为优势种具较高的概率。     

PAM影响剩余污泥与酒精糟液高温共厌氧消化研究

为了使共厌氧消化技术在实际生产中得到应用,研究了广泛使用的絮凝剂阳离子聚丙烯酰胺(PAM)对剩余污泥与酒精糟液高温共厌氧消化的影响,并考察了不同搅拌强度消除PAM的影响.结果表明,阳离子PAM的含量越高,对共厌氧消化反应影响越明显,相对高的搅拌速度有利用消除高分子PAM对质子传输的束缚作用,增加厌氧微生物与污泥的接触机...     

喀斯特地区城市绿地土壤呼吸对降水变化的响应研究

降水是影响土壤呼吸一个重要的影响因子,研究降水对土壤呼吸的影响,对估计和预测陆地生态系统土壤呼吸变化有着重要的意义,但目前自然降水对喀斯特地区城市绿地土壤呼吸影响的研究目前还鲜有报道.本研究利用静态暗箱法,对降水后贵阳城市绿地土壤呼吸速率变化进行了24 h定位监测,对比研究了不同强度降水后土壤呼吸速率变化,并分析了水热...     

断层形变异常强度在跨断层水准测量中的应用——以安徽及临近地区为例

对苏鲁皖地区布设的跨“郯庐断裂”定点短水准资料及“霍山窗”内流动水准资料进行整理。根据断层活动速率求解断层形变异常强度,基于其变化特征与本区中强地震的对比研究,发现在研究区域断层活动整体处于断层形变强度较低的背景下局部断层活动异常对地震预测有一定的指示意义,中强地震多发在异常强度加强的年份或者其后,可以视为中尺度时间的...     

曝气强度对AOA膜生物反应器脱氮除磷性能的影响

考察了曝气强度为2.5、3.75和5.0 m3.（m2.h）-1条件下,厌氧/好氧/缺氧序批式膜生物反应器（AOA MBR）对模拟生活污水同时脱氮除磷性能的影响.结果表明,曝气强度对AOA MBR中COD的去除无显著影响,去除效率均在90%以上.氨氮的去除效果随着曝气强度的增加而提高,3个曝气强度下的平均去除率分别为8...     

穗花狐尾藻生长及酚类物质含量对光照强度的响应研究

沉水植物穗花狐尾藻(Myriophyllum spicatum)能产生对水华蓝藻生长有抑制效应的酚类活性物质。为了揭示光照强度对穗花狐尾藻的生长及其体内酚类物质含量的影响,文章研究了不同光照强度下穗花狐尾藻的生物量及其顶端组织与茎中的可溶性糖、可溶性蛋白、总酚的含量以及与酚类代谢相关酶——苯丙氨酸裂解酶(Phenylalanine ammonia-lyase,PAL)的活性,结果表明:穗花狐尾藻生物量随着光照强度的减弱而显著降低;高光照强度和中等光照强度下,顶端组织中可溶性蛋白、总酚含量和PAL酶活都明显高于茎中各指标;茎中的总酚含量、PAL酶活性在低光照强度下显著高于高光照强度和中等光照强度下。     

Technological Progress,Structural Change and China’s Energy Efficiency

Abstract

China has witnessed rapid economic development since 1978, and during the time, energy production and consumption developed at a tremendous speed as well. Energy efficiency which can be measured by energy consumption per unit of GDP, however, experienced continuous decrease. Theoretically, the change of energy efficiency can be attributed to industry structural change and technological change. In order to explain the transformation of Chinese energy efficiency, we adopt logarithmic mean Divisia index techniques to decompose changes in energy intensity in the period of 1994–2005. We find that technological change is the dominant contributor in the decline of energy intensity, but the contribution has declined since 2001. The change in industry structure has decreased the energy intensity before 1998, but raised the intensity after 1998. Decomposed technological effects for all sectors indicate that technological progresses in high energy consuming industries such as raw chemical materials and chemical products, smelting and pressing of ferrous metals, manufacture of non-metallic mineral products and household contribute are the principal drivers of China’s declining energy intensity.     

Can regional economy influence China’s water use intensity?: based on refined LMDI method

China experienced a decline of water use intensity in the 11th Five Year Plan, but the water use intensity actually increased in 2009. To the best of our knowledge, the index decomposition analysis method was rarely used to analyze changes in water use, and no decomposition analysis has investigated the role of regional economy in the decline of water use intensity. In this paper, we use logarithmic mean Divisia index (LMDI) techniques to decompose the change of water use intensity in the period 2006–2010. We find that the change of industrial water use intensity is confirmed as the dominant contributor to the decline in the overall water use intensity; the regional structure effect and the industrial structure effect is positive to the decline of overall water use intensity; the decline of China’s water use intensity is mainly attributed to the effect of developed eastern provinces; meanwhile, the effect of central and undeveloped western is also positive to the decline of overall water use intensity; at least one out of three effects is positive to the decline of water use intensity in the different provinces; the intensity effect is positive and the industrial structure effect is positive to the declines of China’s water use intensity based on chaining approach except the period 2008–2009, individually; and the deviation of regional structure effect and industrial structure effect between with regional economy and without regional economy in LMDI is 0.9 and 2.3 m³/10⁴ RMB, respectively.     

合肥冬半年降水及所处天气型对大气颗粒物浓度的影响

利用合肥市2015—2017年冬半年环境监测站和自动气象站数据,以及高空、地面天气图资料,运用常规统计和天气学方法分析了降水强度及不同降水天气系统对PM_2.5、PM₁₀浓度的影响.结果表明：冬半年降水日PM_2.5、PM₁₀平均浓度较无降水日分别下降18.1μg·m^-3（23.9%）、38.2μg·m^-3（37.8%）;小于5 mm的日降水量对颗粒物清除效果不明显,且有28%样本PM_2.5和PM₁₀浓度不降反升;当日降水量大于10 mm,位于“优”等级的PM_2.5和PM₁₀浓度比例分别为54%和80%,显著上升.连续降水期间PM_2.5、PM₁₀日均浓度中位值和均值逐日下降,降水第2日PM_2.5、PM₁₀日均浓度降幅最大.合肥冬半年降水天气系统可以分为切变线Ⅰ型、切变线Ⅱ型、低槽冷锋型和...     

东北地区产业结构优化与城市土地集约利用协调性

精准识别产业结构优化与城市土地集约利用的协调状况,对于推动东北地区产业结构转型升级、协调国土空间规划及产业布局具有重要现实意义。运用耦合协调度模型及探索性空间数据分析法,深入探究了2009—2018年东北地区产业结构优化与城市土地集约利用的耦合协调水平及其空间相关性。结果表明：（1）东北地区城市产业结构合理化水平逐年降低,且区域差异程度较大;产业结构高级化水平小幅上升,但不存在明显的空间分异特征。（2）城市土地集约利用水平呈现出先上升后下降的倒“U”型演变特征,并沿着哈大交通经济带的中心城市向两侧梯度递减。（3）产业结构合理化、产业结构高级化与城市土地集约利用协调度分别呈现先上升后下降及稳步上升的演变态势。两协调度均以大连、哈尔滨等城市为中心向外辐射,呈现“多中心多圈层”的空间分布特征。（4）城市两系统协调度存在显著的空间正相关,但显著性逐年减弱,其中高—高聚集类型主要集中在辽中南城市群,低—低聚集类型集中在黑龙江东部城市群。