江汉平原中北部一次区域性暴雨的成因分析

利用常规气象资料和NCEP再分析客观物理量场、卫星云图、多普勒雷达回波产品资料,对2007年7月13日发生在江汉平原中北部的暴雨过程进行了诊断分析。结果表明,（1）高空低槽东移是影响此次强降水过程的主要大尺度环流背景;（2）低层低涡暖切变和低空急流是暴雨的直接影响系统;（3）有利的热力水汽条件和动力条件是强降水产生和维持的机制;（4）卫星云图上“人”字型、“V”字型云系和多普勒速度资料上的“逆风区”、风切变可作为判断强降水落区落点的依据。     

特异性功能光和细菌克制蓝藻水华——对光合细菌抑制蓝藻生长的探讨

分析了蓝藻水华暴发的条件,详细论述了特异性功能光合细菌在蓝藻水华覆盖面治理、蓝藻水华未暴发前治理、内污染源底泥治理、点面源污水治理方面取得的试验成果,并结合对特异性光合细菌的分解技术路线和使用性能的分析得出结论：EPSB生物制剂完全可靠,不存在二次污染,使用投资省、运行费用低。     

基于PCA和SOM网络的洪泽湖水质时空变化特征分析

2010年分4个季度对洪泽湖全湖20个样点的水质理化特征进行了定期监测,采用修正的卡尔森营养状态指数法（TSIm）综合评价了洪泽湖水质的营养状况,同时应用主成分分析（PCA）和自组织特征映射网络（SOM网络）分析了洪泽湖水质的时空变化特征。结果显示：除了水深（WD）和透明度（SD）,洪泽湖的pH、EC、NH+4 N、TN、TP、和CODMn等水质参数季节差异显著。TSIm综合评价结果表明洪泽湖4个季节的水质均呈富营养化状态,夏季富营养化程度最严重。PCA分析表明洪泽湖水质主要受离子和氮盐的控制,磷不是控制洪泽湖水质的最主要因素。SOM网络将全湖20个样点聚为G1、G2和G3三类,G1代表洪泽湖相对封闭的北部区域,有沉水植被分布,水质主要受围网养殖污染的影响;G2代表洪泽湖东部和南部区域,〖JP2〗航运繁忙,直接承接淮河入湖河水,水质主要受淮河入湖河水和航运的影响;G3代表洪泽湖西部水域,沿岸密布养殖池塘且人口密度大,水质主要受养殖废水和城镇生活污水的影响。研究认为,控制外源污染和恢复沉水植被是防治洪泽湖富营养化的有效途径     

Assessment of the red-crowned crane habitat in the Yellow River Delta Nature Reserve, East China

As wildlife habitat is in constant evolution, periodic monitoring is essential to assess its quality. In this study, the change to the red-crowned crane habitat in the Yellow River Delta Nature Reserve was detected from multi-temporal remote sensing data from 1992 to 2008 in a geographic information system. Habitat fragmentation was derived from both physical constraints and human disturbance. The changing habitat quality was assessed against five landscape indices. The results obtained from Landsat TM images indicate that potential habitat shrank 37.9 % during 1992–2001, but recovered 99.4 % by 2008. Suitable habitat shrank by 4,329 ha to a level below that of 1992 despite an increase of 4,747 ha in potential habitat due to an increase of 9,075 ha in fragmented areas. Both landscape indices and the red-crowned crane population reveal that suitable habitat was the most fragmented in 2001, but the least fragmented in 1992. Therefore, it is inadequate to just restore wetland through artificial diversion of channel flow to the Reserve to preserve the crane habitat. Commensurate efforts should also be directed at improving habitat quality by minimizing human activities and spatially juxtaposing water and reed marshes harmoniously inside the Reserve.     

Scientific Basis and Technological Path of Regional Strategic Environmental Assessment

Abstract

The study tries to set up a system to extract strategic environmental assessment (SEA) in exploitation of regional development based on the present situation of environmental assessment in China. First, the article summarizes the emphasis and deficiency of international academic community’s SEA research in the past 10 years. Based on this, the article puts forward the concept and evaluation principles of regional strategic environmental assessment (RSEA). Then the article expounds the necessity of carrying out RSEA. After that, the article discusses in detail the process of RSEA, which includes defining evaluation scope, describing regional background, combing strategic behavior, designing development scenarios, predicting the pressure on environment, assessing environmental impact, screening alternatives and proposing regulation and control schemes.     

The win-win pathway of economic growth and CO2 emission reduction: a case study for China

ABSTRACT

Continuously reducing the CO₂ intensity of GDP is the core strategy for developing countries to realize the dual targets of economic growth and CO₂ emissions reduction. The measures are twofold: one is to strengthen energy saving and decrease energy intensity of GDP and the other is to promote energy structural decarbonization and reduce CO₂ intensity of energy consumption. In order to control global temperature rise no more than 2°C, the decrease in CO₂ intensity of GDP needs surpass 4% before 2030, but it could be merely about 2% based on the current trend. Therefore, all countries ought to speed up the low-carbon transition in energy and economy. As for China, keeping a continuous decline in CO₂ intensity of GDP of 4%–5% will ensure the realization of the NDC objectives, and also promotes the early peaking of CO₂ emissions before 2030. China will play a positive leading role in realizing a win-win low-carbon development coordinating sustainable development and climate change mitigation.     

基于土壤流失的农业面源TN和TP排海系数估算

以黄河三角洲为典型研究区,通过分析区域地表污染物流失风险与入海通量的关系,构建了海岸带农业总氮（TN）和总磷（TP）面源污染排海估算模型.在此基础上,计算了包含水田、水浇地和旱地等耕地类的TN和TP面源污染排海系数,验证表明输出系数估算结果较好.研究区耕地的TN和TP排海系数分别为18.33 kg·（hm²·a）^-1和1.02 kg·（hm²·a）^-1,在夏季面源污染负荷较高.子流域尺度较大的耕地类农业面源污染负荷主要位于支脉河、广利河和小岛河管控区域.TN和TP总负荷较大的行政区主要位于北部黄河口镇和永安镇;较大的单位面积负荷在西南部.因此,需要关注农业面源污染的时间效应,同时协调社会经济发展,从子流域和行政单元的角度制定综合性面源污染防控策略,陆海统筹治理海域污染.     

Removal of polycyclic aromatic hydrocarbons from aqueous solution on soybean stalk-based carbon

Soybean [ (L.) Merr.] stalk-based carbons were prepared by phosphoric acid activation at different carbonization temperatures. Characteristics of the prepared carbon, including specific surface area, iodine number, and amount of methylene blue sorption, were determined. Experiments on phenanthrene, naphthalene, and acenaphthene, as representatives of polycyclic aromatic hydrocarbons (PAHs), removal from aqueous solution by the prepared carbon were conducted at different levels of carbon addition. The results indicated that the specific surface area, iodine number, and amount of methylene blue sorption increased with an increase of carbonization temperature. The maximum values were observed at 700°C and were 287.63 m g, 508.99 mg g, and 90.14 mg g, respectively. The removal efficiencies of phenanthrene, naphthalene, and acenaphthene tended to increase with increasing carbon amounts and carbonization temperature. The optimal removal performance was obtained under the experimental conditions of carbon concentrations of 0.04 g 32 mL and carbonization temperature of 700°C, and the removal efficiencies of phenanthrene, naphthalene, and acenaphthene were 99.89, 100, and 95.64%, respectively. The performance of the prepared carbon was superior to that of commercial activated carbon. Additionally, for the same carbon concentrations, the removal efficiency of PAHs on prepared carbons followed the order: phenanthrene > naphthalene > acenaphthene. Results obtained from this work provide some insight into the reuse of an agricultural residue, and also provide a new application for the treatment of PAHs in contaminated water utilizing activated carbon prepared from agricultural residues.     

Hydraulic management of a soil moisture controlled SDI wastewater dispersal system in an Alabama Black Belt soil

Rural areas represent approximately 95% of the 14000 km(2) Alabama Black Belt, an area of widespread Vertisols dominated by clayey, smectitic, shrink-swell soils. These soils are unsuitable for conventional onsite wastewater treatment systems (OWTS) which are nevertheless widely used in this region. In order to provide an alternative wastewater dosing system, an experimental field moisture controlled subsurface drip irrigation (SDI) system was designed and installed as a field trial. The experimental system that integrates a seasonal cropping system was evaluated for two years on a 500-m(2) Houston clay site in west central Alabama from August 2006 to June 2008. The SDI system was designed to start hydraulic dosing only when field moisture was below field capacity. Hydraulic dosing rates fluctuated as expected with higher dosing rates during warm seasons with near zero or zero dosing rates during cold seasons. Lower hydraulic dosing in winter creates the need for at least a two-month waste storage structure which is an insurmountable challenge for rural homeowners. An estimated 30% of dosed water percolated below 45-cm depth during the first summer which included a 30-year historic drought. This massive volume of percolation was presumably the result of preferential flow stimulated by dry weather clay soil cracking. Although water percolation is necessary for OWTS, this massive water percolation loss indicated that this experimental system is not able to effective control soil moisture within its monitoring zone as designed. Overall findings of this study indicated that soil moisture controlled SDI wastewater dosing is not suitable as a standalone system in these Vertisols. However, the experimental soil moisture control system functioned as designed, demonstrating that soil moisture controlled SDI wastewater dosing may find application as a supplement to other wastewater disposal methods that can function during cold seasons.     

Evaluating the effects of alternative forest management plans under various physiographic settings using historical records as a reference

Using historical General Land Office record as a reference, this study employed a landscape-scale disturbance and succession model to estimate the future cumulative effects of six alternative management plans on the tree species composition for various physiographic settings for the Mark Twain National Forest in Missouri. The results indicate that over a 200-year horizon, the relative abundance of black oak and pine species groups will decrease and the relative abundance of the white oak species group will increase, regardless of management strategy. General Land Office witness tree records provide a measure of tree species composition in the period from 1800 to 1850, prior to the large-scale influx of European settlers. Compared to the tree species composition described in the General Land Office records, the six contemporary management alternatives considered all would lead to a lower abundance of pine species, a higher abundance of red/black oak species, and a slightly higher abundance of white oak species after 200 years. Impacts of management on tree species composition varied with physiographic settings. The projected relative abundance of pine differed significantly across the five physiographic classes over the first 40 years of the simulation. In the medium term (simulation years 41-100) the projected relative pine abundance differed significantly among only four physiographic classes. In the long term (simulation years 100-200) the projected relative pine abundance differed for only one physiographic class. In contrast, differences among physiographic classes in the relative abundance of black oaks and white oaks increased over time. In general, the expected long-term differences in relative tree species abundance among six proposed alternative management plans are small compared to shifts in tree species composition that have occurred from 1850 to the present.