Soil microarthropods (Acari,Collembola) from beach and dune: characteristics and ecosystem context

Soil microarthropods (Acari, Collembola) were analyzed along transects from shore to brown dune in two sandy coastal sites of the North Sea (Jutland, Denmark, and Spiekeroog, East Frisian island, Germany). Predatory mites (Acari: Gamasina) and Collembola were determined to species. The Jutland and the Spiekeroog sites each yielded 22 Gamasina species, 10 of which are common to both areas. Collembola were identified from the Spiekeroog samples only (also 22 species). Largest mite abundances were found in Jutland in primary dunes (419 tsd. ind./m²) and on Spiekeroog in old brown dunes (314 tsd.ind./m²). Compared to the mites, Collembola abundances are low, with maxima of 77 tsd.ind./m² in Jutland (yellow dune) and only 18 tsd. ind./m² on Spiekeroog (old vellow dune). The communities of predatory mites (Gamasina) and Collembola along transects from shore inland to brown dune are quite specific. High similarities are found for the predatory mites between the specific dune sites of the two North Sea areas, particularly for yellow dune. Additionally, preliminary data are presented for the southern Baltic Coast. The findigns are discussed in a broader context. Arguments focus on conservation and biogenic dune stabilization.     

广东山地丘陵土壤的特性

广东山地丘陵面积约占总面积的70％,山地丘陵在广东经济发展中占有重要地位。本文根据长达5年的南方山区土壤资源考察及前人的研究成果,论述了广东山地丘陵土壤中有机质、全氮、颗粒组成、代换性能、矿质营养元素和土壤水分等的特点。建议根据山地土壤资源的优势和生态系统的脆弱性,实行保护性开发、建立良性人工生态系统,因地制宜,因土种植,合理施肥和实行人工灌溉等土壤水分的调控措施。     

直接过滤-臭氧-生物活性炭工艺用于城市污水二级处理出水深度处理的研究

采用砂滤-臭氧-生物活性炭工艺在北京市某污水处理厂开展了以污水再生回用为目的的城市污水深度处理中试研究.在臭氧消耗量5 mg/L,接触时间20 min,生物活性炭空床停留时间(EBCT)为20 min的条件下,出水浊度为1.5 NTU左右,色度接近0,UV254从0.162 cm-1降低到0.08 cm-1,DOC和CODMn分别从10.1 mg/L和12.8 mg/L降低到6 mg/L左右.由于对生物活性炭柱进行了曝气供氧,NH4 -N从40 mg/L降低到5 mg/L左右.     

A field experimental study of lignin sand stabilizing material (LSSM) extracted from spent-liquor of straw pulping paper mills

A new technique was introduced for sand stabilization and re-vegetation by use of lignin sand stabilizing material(LSSM). LSSM is a reconstructed organic compound with lignin as the most dominant component from the extracts of black-liquor issued by straw pulp paper mills. Unlike the polyvinyl acetate or foamed asphalt commonly used for dune stabilization, the new material is plant-friendly and can be used with virescence actions simultaneously. The field experimental study was conducted since 2001 in China‘s Northwest Ningxia Hui Autonomous Region and has been proved that LSSM is effective in stabilizing the fugitive dunes, making the arenaceous plants survive and the bare dune vegetative. The advisable solution concentration is 2% and the optimal field spraying quantity is 2.5L/m^2 The soil nutrients of the stabilized and greened dune, such as organic matter, available phosphorous and total nitrogen are all increased compared with the control treatment, which is certainly helpful to the growth of arenaceous plants. The technique is worthwhile to be popularized because it is provided not only a new method for desertification control but also an outlet for cleaning contaminants issued from the straw paper mills.     

低山丘陵区土地整理与可持续发展研究——以广安区为例

为探讨低山丘陵区土地整理的模式,利用MAPGIS软件综合处理研究区大量与土地利用相关的基础数据,针对低山丘陵区土地资源利用的现状及特点,从多方面说明土地整理的迫切性.依据经济、社会、生态相统一的目标,划定3个土地开发整理区,确定开发整理的方向及重点.研究得出土地整理是改善用地结构、协调人地矛盾的有效途径.结论:土地整理应首先以保护耕地数量和质量为核心,集约利用土地,促进耕地总量动态平衡;加强土地管理,提高土地的利用率和综合效益.     

印染废水处理工艺改进的应用研究

通过对湘潭纺织厂废水处理工艺存在的问题进行研究和分析 ,对其废水处理工艺进行了改进。采用“二级生物接触氧化 砂滤 活性生物炭”工艺后 ,废水经其处理 ,水质各项指标超过国家一级排放标准 ,水质可以完全回收利用 ,废水处理成本下降 1 3左右。     

Emissions of Particulate and Gaseous Pollutants within the Keelung Harbor Region of Taiwan

The Keelung port, which is located on the northern tip of Taiwan, right next to the Taipei metropolitan area, is an important international harbor. However, any air pollutants generated from the Keelung port region, immediately travel to the neighboring Keelung city, and greatly impact the residents' daily life and the quality of their environment. This study has investigated and quantified pollution emissions, from the Keelung port region, between 1997 and 2002. Emissions from major air pollution sources were estimated. The estimated results indicated that total TSP (total suspended particles) emissions had significantly increased, from 5221 ton/yr in 1997 to 262 687 ton/yr in 2002, due to the greatly increased volume of sand imported into Keelung Harbor. Quantities of other emissions, such as SO₂, NO₂, CO and HC remained stable and were 440, 207, 78 and 25 ton/yr, respectively, on average, with variations within 7% over the previous six-year period. By examining the emissions from pollution sources, it was found that TSP emissions mainly originated from re-suspension of dust, due to both vehicle movement and the sand unloading process; this accounted for over 99% of the total TSP emissions produced in the port region. About 80% of the total SO₂ emissions originated from the main ships' engines within the Keelung port region, due to the use of fuel with a high sulfur content. In addition, loading/unloading machines within the port region were the major sources of NO₂, CO and HC pollution emissions, which comprised 54, 58 and 66% of the total emissions of these pollutants, respectively. TSP emissions from Keelung port were much higher than from the neighboring Keelung city; hence, alleviating TSP emissions should be the first priority for air pollution reduction within both the port of Keelung and Keelung city.     

环丙沙星在石英砂中的吸附迁移特征及参数分析

通过批量静态吸附实验,分析不同pH、离子强度、粒径下环丙沙星在石英砂上的吸附特征,实验数据用Langmuir与Freundlich两个方程进行拟合;并做室内石英砂柱迁移实验,探讨了不同因素对环丙沙星在石英砂中运移的影响;获得了示踪剂Br-和环丙沙星的穿透曲线,并用HYDRUS-1D软件对实验结果进行了模拟.研究表明:环丙沙星在石英砂上的吸附能力与pH、离子强度及粒径大小成负相关.随着pH、离子强度及粒径增大,出流时间变短,达到C/C_0峰值的时间也变短,从出流到相对浓度衰减为零整个过程的时间跨度越小.在低离子强度下,环丙沙星在不同粒径的石英砂中的运移,一般粒径越大,出流越早,峰值越高.描述溶质运移的非平衡一点模型(OSM)能够较好地模拟环丙沙星在石英砂中的运移过程,用数值反演得到的参数所求出的阻滞因子R_d值比根据Freundlich方程拟合得到的参数求出的R_d值要小,但它们均符合静态吸附实验和动态迁移实验的特点.pH越大,模拟得到的分配系数K_d值越小,分形系数β值、一阶速率系数ω值均很小且无明显变化规律;离子强度越大,模拟得到的分配系数Kd值、分形系数β值及一阶速率系数ω值就越小.     

首都圈防沙治沙水土资源空间优化配置研究——以大兴、怀来、张北为例

首都圈是近年来北京沙尘暴天气日益严重的重要沙尘源区之一。研究区中大兴区代表的是华北平原北缘落叶阔叶林灌草丛典型区;怀来县代表的是桑干河、洋河盆地灌木草原典型区;张北县代表的是坝上高原西部干草原典型区。论文通过了解水土资源利用的变化情况,分析水土资源利用现状和存在问题;利用中国资源环境遥感数据库中的土地利用现状、中国1∶1000000土地资源图等数据,以水资源为最重要的限制因素,通过灰色线性规划模型,以防沙治沙和发展经济、实现区域可持续发展为目标,进行水土资源优化配置;结合不同区域水土资源利用的突出问题,将水土资源优化配置方案落实到空间;建立区域水土资源比较合理、有效利用的方案。大兴的重要措施是平原旱耕地转变为中覆盖度草地,怀来是陡坡地退耕,张北是提高草地的覆盖度。     

Simulation test on mixed water and sand inrush disaster induced by mining under the thin bedrock

Coal seam mining under thin bedrock will make transmission fissure zone go through to the water-rich aquifer under the covering layer, which will cause water flooding and sand gushing in the working face. The test model of the mixed water and sand inrush transfer and inrush was designed and manufactured to simulate the startup, transfer and inrush process of the mixed water and sand inrush in the overburden fracture channel. The characteristics of the mixed water and sand inrush in the fracture channels were researched. The variation characteristics of water pressure in different positions of the fracture channel were revealed through analyzing “\/” type fracture form which is wide at the top and goes narrower down to the base, of various inclination angles under the water pressure of 0.06 MPa and 0.08 MPa. The results show that the water and sand inrush took place instantly in the mined area. Based on the characteristics of water pressure variations, changes in water pressure are divided into two phases: rising phase and lowering to stable phase. Under the other same conditions, when the fissure channel angle increases, the pore water pressure and its sudden drop will increase too, and the inrushing process will get more rapidly; the bigger the water pressure is, the pore water pressure increases more rapidly and violently. From this, the transfer characteristics and dynamic mechanism of the mixed water and sand inrush were explored.