Impact of trampling on sandy beach macrofauna

The effects of varying intensities of human trampling on sandy beach macrofauna were investigated at an exposed beach on the Eastern Cape coast. An experimental approach investigated the survival rates of four macrofaunal species which were subjected to human trampling at different intensities in a holiday-activity simulation. It was found that the clamDonax serra was slightly impacted at all trampling intensities whileDonax sordidus and the isopodEurydice longicomis were affected only at high trampling intensities. Vigorous beach games, such as volleyball, may have a damaging effect onD. serra. In a second experiment, the severe effects of human trampling onD. serra and the benthic mysidGastrosaccus psammodytes were investigated using numbered animals in enclosures. The results indicated that few members of the macrofauna were damaged at low trampling intensities but substantial damage occurred under intense trampling.     

Social trends of the people of the region of Eastern Macedonia and Thrace-Greece: about the potential of using biofuels from forest products residues

In the framework of enquiry of biomass usage possibilities in our country, a research was made through the whole Eastern Macedonia region, related to disposal possibilities from the production conveyors and usage possibilities from the region’s residents and businessmen, of biofuels that come from mechanical wood treatment residues and from the residues of agricultural production, in wooden form, known with the term wood pellets or wood briquettes. From the present study, it came to light that there is an intense interest for direct personal usage and application of biomass for the residents or occupational spaces heating. The necessary biomass quantity for the entire region’s households is estimated up to 205,520 t. From the biomass usage as a combustible material, a 680 €/year and household about, is made. The potential investments that will be made to the region seem to have a very short depreciation, but a business plan and a marketing plan syntax are considered as necessary for the result’s maximisation.     

区域分异视角下乡村企业入城意愿分析——基于浙、豫、川三省193家企业的实证研究

乡村企业入城是实现我国城镇化发展的基本路径。利用浙江、河南、四川三省193家乡村企业的实地调查数据,运用多元有序Logistic回归模型进行相关验证,实证分析我国东中西部三个省份的乡村企业入城意愿及其影响因素。通过对调研数据的描述统计发现:有58.55%的乡村企业主有入城意愿,仅有21.24%的乡村企业主不愿意或非常不愿意搬迁,集群环境、土地价格、运输成本等是企业愿意搬迁的主要原因,土地价格政策、当地经济发展水平、产品产销信息、集群环境是影响企业搬迁方向的重要因素,当地的土地、税收和融资等政府政策对于企业是否入城产生重要影响。通过多元有序Logistic回归模型估计结果表明:企业总资产、土地价格、运输成本、集群环境、与政府关系对入城意愿有显著负向影响,税收政策有显著正向影响,这些影响因素主要是通过影响企业的显性成本(土地价格、运输成本),以及企业的交易成本、寻租成本等隐性成本(集群环境、与政府关系和税收政策),进而影响企业的迁移意愿,且浙江、河南与四川三地计量结果差异显著。在上述研究的基础上,本文提出相应的政策建议。     

Specific features of the oribatid fauna in high-mountain pine forests of the Eastern Caucasus in relation to altitudinal zonality

The abundance, structure, and distribution of oribatid communities in high-mountain pine forest biotopes of the Eastern Caucasus are described in dependence on elevation above sea level. The oribatid fauna of high-mountain pine forests proved to be characterized by high abundance, an assortment of dominants, and species richness. It was shown that, as the elevation increases, specific dominants typical of particular altitudinal zones appear in communities, and changes in the mass species occur. These species are stable in terms of their long-term dynamics, and zonal groups (communities) demonstrate a high species diversity.     

Shipboard Measurements of Nitrogen Dioxide,Nitrous Acid,Nitric Acid and Ozone in the Eastern Mediterranean Sea

Measurements of nitrogen dioxide, nitrous and nitric acids as well as ozone were made using newly developed instrumentation onboard the research vessel Aegeon in the Aegean Sea between 25th–29th July 2000. Typical nitrogen dioxide concentrations observed aboard the boat were 4–6 ppb (v/v) with a broad maximum of 20–30 ppb (v/v). Ozone concentrations typically ranged between 40 and 80 ppb (v/v). Mixing ratios of both nitric and nitrous acids in the ambient air of the Aegean Sea were mainly below 50 ppt (v/v). The data also showed a number of short pollution episodes with rapid changes in the concentration of reactive nitrogen compounds [nitrogen dioxide maximum up to 164 ppb (v/v), nitric acid maximum up to 12 ppb (v/v), nitrous acid maximum up to 2.7 ppb (v/v)] and ozone [maximum up to 88 ppb (v/v)]. These episodes were correlated with pollution plumes originating from boats upwind, at short distance, from the R/V Aegeon. The measurements revealed the importance of nitrous and nitric acids for the transport of nitrogen to marine biota in busy ship lanes.     

Sediment and carbon accumulation in a small tidal basin: Yuehu,Shandong Peninsula,China

A small sedimentary basin (the Yuehu lagoon), located at the eastern tip of Shandong Peninsula, China, was selected to study its filling by sediment and the vertical flux of particulate organic carbon in response to natural/anthropogenic processes. Surficial and short core sediment samples were collected and analyzed to obtain data sets of grain size, organic carbon content, deposition rates and vertical fluxes of sediment and organic carbon. The analytical results show that the lagoon is covered mainly with fine-grained sediments with high deposition rate and particulate organic carbon content being found from the central part of the mud deposit. The sediment balance of the lagoon indicates high denudation rates of the catchment basin, which may be related to soil erosion in response to farming and land use pattern changes. Furthermore, preliminary analysis of the organic carbon fluxes of the Yuehu lagoon and other embayments of the region shows that these coastal systems make an important contribution to the regional shallow sea carbon burial.     

2015~2021年陕西关中城市群臭氧污染变化趋势

基于2015~2021年环境监测数据和气象再分析资料,利用Mann-Kendall检验法和Sen斜率法等统计手段揭示了陕西关中城市群臭氧（O₃）浓度时空变化特征和年际变化趋势,并从气象、排放源和区域传输等方面分析了趋势形成的原因.结果表明：①2015~2021年,关中城市群O₃浓度评价值（MDA8第90百分位数）最高的城市是咸阳市,浓度评价值多年平均值为162 μg·m^-3,O₃浓度平均值（MDA8年均值）和O₃浓度背景值（MDA8第5百分位数）最高的城市是铜川市.②关中城市群O₃浓度表现为单峰型日变化特征,并呈现夏季>春季>秋季>冬季的年变化特征.夏季咸阳O₃浓度平均值最高,其他季节铜川O₃浓度平均值最高.③2015~2021年,陕西关中城市群O₃浓度背景值呈现出上升趋势,区域浓度背景值平均上升速率为2.20 μg·（m³·a）^-1,但是O₃浓度评价值并未表现出有统计显著性的变化趋势.此外,关中城市群O₃浓度变化趋势与季节密切相关,其中冬季O₃浓度上升趋势显著,其他季节大部分城市O₃浓度无明显变化趋势.④关中城市群及周边地区挥发性有机物（VOCs）减排幅度普遍小于氮氧化物（NO_x）的不合理减排结构、滴定效应减弱以及区域传输等因素共同作用,导致关中城市群冬季O₃浓度升高.     

陇东黄土高原石油污染土壤环境因子对金盏菊(Calendula officinalis)-微生物联合修复的响应

为筛选适合陇东黄土高原石油污染土壤修复植物,选取当地"适生"植物金盏菊(Calendula officinalis)联合微生物菌剂开展了为期5个月的原位修复实验.采用常规方法和PCR-DGGE技术分析了修复过程中土壤理化性质、酶活性及土壤微生物群落遗传多样性等15项土壤环境因子的动态变化情况及其对金盏菊生态修复的响应.结果表明,随着原位修复的进行,1土壤脲酶、多酚氧化酶、过氧化氢酶及脱氢酶活性均不同程度呈增加的趋势(p0.05).2土壤TPHs、p H、有机质、含盐率的变化情况不尽相同,但总体呈下降的趋势(p0.05);土壤碱解氮、速效磷及速效钾含量总体呈上升趋势(p0.05).3土壤微生物群落遗传多样性结果显示,Shannon-Wiener多样性指数和Pielou均匀度指数整体呈逐步增加的趋势.4PCA分析结果显示,土壤脲酶、脱氢酶及碱解氮等环境因子对金盏菊修复表现为促进作用,而有机质含量过高将不利于金盏菊的植物修复.金盏菊和微生物菌剂联合修复过程中,土壤多酚氧化酶、速效磷、脱氢酶及速效钾发挥主要作用,而土壤TPHs和含盐率过高则影响了联合修复效果.本研究旨在分析金盏菊用于陇东地区油污土壤的生态响应,结果有助于筛选出适合陇东黄土高原土壤类别-适生植物-土著降解菌群的组合,利用乡土物种的适生性降低修复成本,为陇东地区油污土壤生态修复提供新的技术方案和背景资料.     

秸秆还田对冬小麦-夏玉米农田土壤固碳、氧化亚氮排放和全球增温潜势的影响

旱地农田温室气体净排放(以全球增温潜势表示)主要取决于土壤固碳速率和氧化亚氮(N2O)排放量.基于长期定位施肥试验,综合分析2010～2017年表层(0～20 cm)土壤有机碳含量和2014～2017年N2O排放通量的观测结果,定量评价秸秆还田对关中平原冬小麦-夏玉米农田土壤固碳速率、N2O年排放量和全球增温潜势的影响...     

基于叶绿素a分级的东部湖区富营养化标准研究

文章基于东部湖区142个湖泊的水质和水生态数据,选取富营养化的原因变量和响应变量,采用叶绿素a六段分级的方法,得到东部湖区各指标富营养化控制的分级标准值,与GB3838-2002中的各指标值相比,所得到的分级富营养化控制标准值均超过III类水标准,这为东部湖区湖泊的管理和控制提供了理论依据。