国内外土地利用区划研究的回顾与展望

土地利用区划是从区域角度观察和研究地域综合体,探讨土地利用的发展历史、现状特点、变化过程及趋势,从最大限度发挥土地生产潜力及改善土地生态系统的结构与功能出发,对土地的合理利用方向,包括确定国民经济各部门用地的合理分配、结构和布局形式等,在地域上进行分区。通过简要回顾国内外土地利用区划研究的发展历程,总结了土地利用区划研究的理论方法特点及存在的问题,并在此基础上探讨今后土地利用区划研究的重点及发展方向：从自然要素向自然与人文要素有机结合方向转变;从大空间尺度向多空间尺度方向转变;从传统的区划方法向综合集成的新技术手段转变;从静态的区划研究向多要素、多过程耦合的动态区划研究方向转变。     

A study on the factor market distortion and the carbon emission scale effect of two-way FDI

Based on the data of 30 Chinese provinces for the period from 2004 to 2015, this paper expounds the carbon emissions effect of two-way foreign direct investment (FDI) from the perspective of scale effect and factor market distortions. This study uses Kaya identity to decompose carbon emission and construct simultaneous equations model to empirically examine the factor market distortion and the carbon emission scale effect of two-way FDI. The results show that the inward foreign direct investment (IFDI) increase regional carbon emission through scale effect and also exacerbates factor market distortion in China, whereas the outward FDI trends reduce carbon emission and reduces factor market distortions in China. The study also shows that human capital, research and development (R&D), trade openness, and capital accumulation are important determinants of two-way FDI. Therefore, the study proposes that IFDI policies should focus on acquiring green technologies. In addition, the domestic enterprises should be encouraged to participate in global business.     

Thinking inside the basin: scale in transboundary water management

While transboundary waters are widely advocated to be best managed at the basin level, practical experience in transboundary waters at the basin vis‐à‐vis other scales has not been systematically examined. To understand past experiences in transboundary water management at alternate scales, this paper: (i) determines the relative abundance of water treaties at different scales and (ii) elucidates how transboundary water law varies according to the scale to which it applies. The paper developed a scale typology with six groups, and systematically applied it to stratify transboundary water treaties. Treaty contents were then compared across scales according to the following set of parameters: primary issue area, temporal development, and important water management attributes. Results of this work reveal: (i) treaties tend to focus on hydropower and flood control at smaller scales, and organizations and policies at larger scales; (ii) a temporal trend toward treaties concluded at larger scales; and (iii) a higher proportion of treaties is at larger scales in Africa and Asia than in Europe and the Americas. These findings suggest that smaller scale cooperation may constitute a more constructive scale in which to achieve development‐oriented cooperation. Further, scope may exist to complement basin scale cooperation with cooperation at smaller scales, in order to optimize transboundary water management. In the context of basin‐wide management frameworks, Africa and Asia may benefit from greater emphasis on small‐scale transboundary water cooperation.     

Carbon emission reduction and cost–benefit of methane digester systems on hog farms in China

Three different sizes of hog farms were selected to analyze the carbon emissions reduction and the cost–benefit of three methane digester systems. The sizes of the digesters are 2,200, 2,200 and 800 m³, respectively. The sales of slaughter hogs from them are 50,000, 35,000 and 10,000 head, respectively. The carbon emissions reductions were 5,237, 4,017, and 1,334 tons, respectively. The results show that while the methane digester systems have a significant effect on carbon emissions reduction, it is difficult to operate the systems sustainably. If the carbon emissions reduction can be traded at high enough prices in the carbon offset markets, then the systems will be profitable and sustainable. Newly established China's domestic carbon offset market could provide this possibility, but more government support is needed. In addition, this study shows that scale economies make the digester adoption relatively more profitable for larger farms than smaller ones.     

大尺度障碍物与泄爆面对天然气内爆炸的协同作用规律研究

为阐释民用建筑内部大尺度物品与门窗等泄爆面对天然气爆炸灾害的协同作用机制,基于典型厨房空间布局及内部物品特征,借助计算流体动力学技术研究了不同泄爆面开启压力和不同大尺度障碍物体积阻塞率条件下天然气内爆炸火焰速度、爆炸超压的分布规律。研究结果表明:大尺度障碍物与泄爆面对室内天然气爆炸过程具有显著的协同作用,共同促进火焰速度与爆炸超压的显著增长,并缩短峰值超压到达时间;大尺度障碍物的存在虽然显著降低了室内天然气的体积,但从增加房间内湍流源和相对长径比的角度进一步促进了泄爆效应;大尺度障碍物与泄爆面协同作用下,室内火焰速度呈现明显的阶段性特征,并在泄爆面附近发生波动。研究结论可为民用建筑物内气体爆炸事故调查分析和灾害评估提供科学依据。     

长三角典型区土壤重金属有效态的协同区域化分析、空间相关分析与空间主成分分析

以昆山市为典型区,采集了126个表层土壤样品,通过多元统计学、地统计学与GIS技术相结合,采用基于协同区域化理论的因子克立格法探讨了长三角多个土壤重金属有效态的区域分异,并在剖析不同空间尺度有效态重金属的空间结构特征基础上,应用空间相关分析和空间主成分分析来揭示引起这种分布格局的成因和污染来源,结果表明,昆山土壤有效态重金属服从正态或对数正态分布,变异系数较大,有效态Cd污染最重.重金属有效态在空间上可划分为块金尺度、小空间尺度（15 km左右）和大空间尺度（40 km左右）,它可用3个尺度的实验（交叉）变异函数的协同区域化模型线性拟合.空间相关分析中,Cd和Zn在3个尺度中的相关性均极显著,且元素在小尺度和大尺度的相关性比块金尺度更强,大尺度的负相关特征较其它尺度明显.空间主成分分析表明,不同尺度的空间污染来源不同.重金属有效态第一、二主成分的空间分布格局结果表明重金属有效态含量与工业活动、污水灌溉和土壤性质密切相关.     

Health and environmental assessment of mercury exposure in a gold mining community in Western Mindanao, Philippines

The small-scale gold mining activities using mercury began in the late 1980s in Sibutad, Western Mindanao. It is located very near the Murcielagos Bay with tailing ponds directly discharging into bodies of water. This cross-sectional study aimed to determine the health and environmental effects of gold mining activities on the community. Residents were randomly selected and classified into two groups, namely, the directly exposed and indirectly exposed populations using a set inclusion criteria. Complete medical and laboratory examinations were performed. Environmental and biologic samples were collected for total mercury and methylmercury determinations. The results showed that the directly exposed group had significantly higher mean blood total mercury and methylmercury levels in comparison with the indirectly exposed population. Although there were no significant differences between hair total mercury and methylmercury levels, there was a trend for higher levels of these biomarkers among the directly exposed residents as compared with the unexposed group. The absence of statistically significant differences may be attributable to the small sample size. Ambient air quality monitoring for mercury exceeded the allowable levels. However, levels of mercury in drinking water and sediments were within allowable limits. Frequency of gastrointestinal complaints was significantly associated with elevated hair methylmercury levels (p=0.02). Also, there appears to be a trend towards higher blood total mercury levels and frequency of gastrointestinal complaints (p=0.09). An interesting finding in this study was the increasing incidence of elevated diastolic blood pressure with elevated hair total mercury levels (p=0.07). Mercury storage at home is a risk factor.     

聚合氯化铝-腐殖酸(PACl-HA)絮体的物理与分形特征研究

采用低温急速冷冻-真空干燥技术制备了PACl-HA絮体的粉末样品,研究了这些样品的物理与分形特征.结果表明,PACl-HA絮体具有无定形结构,主要组成元素为C、O、Al,所含特征官能团保留了絮体组成原料的一些特征;絮体的BET比表面积为130～161 m²·g^-1,BJH累积吸附孔体积为0.38～0.52 cm³·g^-1,BJH脱附平均孔径为7.7～9.6nm,PSD峰值对应孔径8.4～11.2nm.PACl-HA絮体具有自相似性的粗糙表面,呈现多尺度分形特征;图象法和N₂吸附/脱附等温线法确定的表面分形维数Ds分别为2.03～2.26、2.24～2.37,前者的分形尺度大约处于23～390nm之间,主要属于絮体外表面尺度,而后者的分形特征尺度区间的下限大约为0.2nm,属于孔表面尺度;另外,对同一絮体,N₂吸附法和脱附法确定的孔表面分形维数不同.热力学模型计算出的D_s远大于3,与Sahouli等的研究不符.     

武汉汉阳地区城市集水区尺度降雨径流污染过程与排放特征

2005年4月至8月对武汉市汉阳地区十里铺集水区进行了8次径流污染过程的水量、水质研究.结果表明,城市集水区尺度径流污染过程是降雨径流对整个集水区地表、排水系统中累积污染物的冲刷、携带过程,受集水区累积污染物数量、污染物可冲刷性和降雨径流特征的共同影响.城市降雨径流中初期污染物浓度显著高于后期,污染物浓度的峰值提前于径流的峰值,具有明显的初期冲刷效应.8次监测结果的算术平均值,初期5 mm、10 mm和15 mm降雨径流中TSS的负荷分别占总负荷的48%、68%和78%.初期径流中TSS的负荷与晴天累积天数呈线性正相关关系.     

集输油环境氟橡胶O形圈老化行为实验研究*

为研究氟橡胶O形圈在集输油环境中的老化行为特征,以长庆油田使用的氟橡胶O形圈(位于非金属复合管连接接头处)为研究对象,采用宏观与微观相结合的方法,通过挂片实验分析氟橡胶O形圈在不同介质（采出油,采出水）、温度（25,50 ℃）、压力条件（0.1,4,6 MPa）下老化后的形貌、质量、拉伸性能及硬度。结果表明:采出油、采出水均能引起O形圈发生溶胀,从而降低O形圈的强度、韧性、硬度;采出水引起的溶胀显著高于采出油更易导致O形圈表面产生坑洞缺陷;渗透速率随温度升高而急剧增加,压力对渗透速率的影响不明显;硬度降低较小,最大降幅为4.17%。结合现场服役813 d的密封圈SEM形貌,证实集输介质渗透会引起氟橡胶圈溶胀、导致表面产生坑洞等缺陷。