Testing the presence of marine protected areas against their ability to reduce pressures on biodiversity

Marine protected areas (MPAs) are the preferred tool for preventing marine biodiversity loss, as reflected in international protected area targets. Although the area covered by MPAs is expanding, there is a concern that opposition from resource users is driving them into already low-use locations, whereas high-pressure areas remain unprotected, which has serious implications for biodiversity conservation. We tested the spatial relationships between different human-induced pressures on marine biodiversity and global MPAs. We used global, modeled pressure data and the World Database on Protected Areas to calculate the levels of 15 different human-induced pressures inside and outside the world's MPAs. We fitted binomial generalized linear models to the data to determine whether each pressure had a positive or negative effect on the likelihood of an area being protected and whether this effect changed with different categories of protection. Pelagic and artisanal fishing, shipping, and introductions of invasive species by ships had a negative relationship with protection, and this relationship persisted under even the least restrictive categories of protection (e.g., protected areas classified as category VI under the International Union for Conservation of Nature, a category that permits sustainable use). In contrast, pressures from dispersed, diffusive sources (e.g., pollution and ocean acidification) had positive relationships with protection. Our results showed that MPAs are systematically established in areas where there is low political opposition, limiting the capacity of existing MPAs to manage key drivers of biodiversity loss. We suggest that conservation efforts focus on biodiversity outcomes and effective reduction of pressures rather than prescribing area-based targets, and that alternative approaches to conservation are needed in areas where protection is not feasible.     

Solving the probabilistic reserve selection problem

The Reserve Selection Problem consists in selecting certain sites among a set of potential sites for biodiversity protection. In many models of the literature, the species present and able to survive in each site are supposed to be known. Here, for every potential site and for every species considered, only the probability that the species survives in the site is supposed to be known. The problem to select, under a budgetary constraint, a set of sites which maximizes the expected number of species is known in the literature under the name of probabilistic reserve selection problem. In this article, this problem is studied with species weighting to deal differently with common species and rare species. A spatial constraint is also considered preventing to obtain too fragmented reserve networks. As in Polasky et al. (2000), the problem is formulated by a nonlinear mathematical program in Boolean variables. Camm et al. (2002) developed a mixed-integer linear programming approximation that may be solved with standard integer programming software. The method gives tight approximate solutions but does not allow to tell how far these solutions are from the optimum. In this paper, a slightly different approach is proposed to approximate the problem. The interesting aspect of the approach, which also uses only standard mixed-integer programming software, is that it leads, not only to an approximate solution, but also to an upper limit on the true optimal value. In other words, the method gives an approximate solution with a guarantee on its accuracy. The linear reformulation is based on an upper approximation of the logarithmic function by a piecewise-linear function. The approach is very effective on artificial instances that include up to 400 sites and 300 species. Within an average CPU time of about 12 min, near-optimal solutions are obtained with an average relative error, in comparison to the optimum, of less than 0.2%.     

垃圾焚烧发电厂配套设施及污染防控问题浅析

文章分析了垃圾焚烧技术的利弊，详述了垃圾焚烧发电厂必要的配套设施的项目内容，指出这是垃圾焚烧发电系统不可分割的部分。认为垃圾焚烧发电发展前景广阔。     

汉江上游黄坪村段东汉时期古洪水水文学研究

对汉江上游郧县黄坪村剖面的沉积学特征及所在河段地貌进行了研究。发现剖面中夹有典型古洪水沉积物,其记录了发生于1 900~1 700 a B.P的古洪水事件。根据水文学和沉积学原理,利用尖灭点法和SWD厚度与含沙量关系法恢复的古洪水行洪水位高程分别为15495和15685 m,用比降法恢复的古洪水洪峰流量为65 320和74 442 m3/s。根据2011年汉江洪水洪峰痕迹高程用相同方法反推洪水流量,用Baker提出的河流流域面积与洪水洪峰流量关系进行了验证,证实所恢复的古洪水洪峰流量是合理的     

BDD和PbO2电极电化学氧化苯并三氮唑的对比研究

分别构建了以掺硼金刚石膜电极(BDD)和二氧化铅电极(Pb O2)为阳极的电化学体系,对比考察了两种电极对难降解有机污染物苯并三氮唑(BTA)的降解及体系的矿化效果,并从电极产生羟基自由基(·OH)的数量与形态角度深入探讨了影响电极矿化能力大小的内在因素.结果表明:1BDD和Pb O2电极均对BTA有较好的降解效果,电解12 h后BTA去除率分别为99.48%和98.36%,但BDD电极的矿化能力明显强于Pb O2电极,电解12 h后矿化率分别为87.69%和35.96%;2BDD体系阳极·OH产生速率和阴极H2产生速率均低于Pb O2体系,即表面活性位点数量少于Pb O2电极,因此·OH数量不是决定矿化能力大小的关键;3BDD电极表面吸附氧活性更强,结合能(532.37e V)大于Pb O2(530.74e V),且表面吸附层更薄,产生的·OH形态更自由,是决定其具有更大矿化能力的关键因素.     

生活垃圾卫生填埋项目环境影响评价探讨

针对城市生活垃圾填埋场环境影响评价中的选址问题进行了讨论,同时对垃圾渗滤液的水质进行了阐述以及对渗滤液的产生量合理计算进行了分析。     

Treatability of volatile chlorinated hydrocarbon-contaminated soils of different textures along a vertical profile by mechanical soil aeration: A laboratory test

Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons(VCHs). Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures(silty,clayey, and sandy soils) along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform(TCM) and trichloroethylene(TCE). Mechanical soil aeration was effective for remediating VCHs(removal efficiency 98%). The volatilization process was described by an exponential kinetic function.In the early stage of treatment(0–7 hr), rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.     

城市垃圾场空间扩张遥感监测——以贵阳市高雁垃圾场为例

为研究垃圾场对城市发展的影响,利用2002、2006、2010、2013、2015和2016年6个时相的高分辨率遥感影像,通过目视解译监测贵阳市高雁垃圾场的时空扩张动态。以1︰10 000地形图为参考的多项式方法进行几何校正基础上,采用目视解译方法提取各时相的垃圾场占地区域,并分析高雁垃圾场扩张特征。在此基础上,通过GIS的空间分析功能,结合实地调查进行垃圾场的人口影响分析。结果表明,贵阳高雁垃圾场空间扩展迅速,垃圾场堆积区面积从2002年的5.4 hm~2扩展到2016年的46.5 hm~2,新增面积超过40 hm~2,年均新增面积超过2.9 hm~2约54%。垃圾场影响的人口数量超过10万,显著影响了区域的大气、水和植被。最后,遥感对中国的城市垃圾场监测具有重要作用,在遥感监测基础上,掌握垃圾场演变动态,能够为城市乃至区域可持续发展提供参考。     

基于Dijkstra算法的乡镇消防站选址问题

在规划时,影响消防站设置的因素很多,最短路径问题是消防站选址的关键内容。主要讨论了基于Dijkstra算法在广大农村辖区内合理的进行乡镇消防站选址的问题,简述了Dijkstra算法在乡镇消防站选址中的应用思路,并通过解决实际问题论证了这种方法的可行性和实用性。在解决实际问题中将各乡镇的交通网络图等效为带权的拓扑结构图,将消防站和各乡镇转化为图上的各个顶点,得出消防站节点到所有节点的最短路径（最短耗时）,然后根据实际需要来选择我们所需的路径和节点并建立合理的消防站。该方法为乡镇消防站选址的综合解决方案创造了有利条件,对于广大农村辖区的乡镇消防站选址提供了好的思路。     

化工厂场地酸化土壤工程化中和修复案例研究

对江苏某化工厂酸化地块进行了氧化钙中和修复工程研究。Ⅰ、Ⅱ、Ⅲ号地块剖面混合土样pH值分别为3.56、4.68和4.74,土壤修复目标定在pH值为6~8基本近中性。通过室内试验确定Ⅰ、Ⅱ、Ⅲ号地块土壤生石灰掺混比例为0.5%、0.3%和0.3%;现场中试后Ⅰ、Ⅱ、Ⅲ号地块石灰掺混比例调整为0.7%、0.35%和0.3%;中试结果用于场地机械搅拌工程修复,修复过程中定期随机采样对中和效果进行连续监测。监测结果基本达标后请第三方对修复效果进行评估,最后土壤回填压实。修复结果表明借助于科学的石灰添加量和工程机械混合措施,能快速有效地修复酸化地块土壤。