海平面上升,海岸带灾害与海岸防护问题

全球变暖导致海平面上升。近百年来中国海平面以１．４～２．０ｍｍ／ａ的平均速率上升，预计下世纪还将加速，几个大河三角洲沿岸因受地面下沉影响，２０５０年相对海平面上升幅度可能高出ＩＰＣＣ（１９９０）最佳估计值的１倍左右。海平面上升会加剧多种海岸带灾害，尤其是台风风暴潮的发生数和成灾数增加。近２０年来由于沿海人口、资产密度剧增以及海堤标准偏低，致使风暴潮灾损失逐年增大，预计下世纪海岸带灾害损失还将大幅度提高。面对海平面上升和海岸带灾害的不断发展以及越来越多的低滩围垦情况，必须认识加强海岸防护对发展区域经济的重要性。增加投入，采取护坡与保滩相结合、工程措施与生物措施相结合等综合防护对策，争取在较短时间内将我国大部分海韩的标准在现有基础上普遍提高一个等级。     

环境因素对土壤含硫气体释放的影响

研究了温度、光照条件两种环境因素对添加不同硫源（胱氨酸、硫酸二乙酯和硫酸钠）土壤含硫气体释放的影响。结果表明,随着培养温度升高,含硫气体释放量增大,而且释放气体种类增多。COS在各种不同处理的土样中均有释放。除添加硫酸二乙酯的土样外,其它各种土样COS释放量与培养温度有很好的相关性,相关系数在0．95以上。添加胱氨酸的土样,含硫气体释放明显高于其它土样,光照条件变化对各种含硫气体释放量影响不大,但在弱光和无光照条件下检出的含硫气体种类较多。     

改性TiO2对X-3B的光催化性能及其降解动力学研究

以活性艳红X-3B为模型化合物,比较了改性前后TiO2光催化活性的变化.试验结果表明,通过改性大大提高了TiO2的光催化活性,Fe3+和Ag+的掺杂量均有一个最佳值,在试验的掺杂范围内Fe3+和Ag+的最佳掺杂量分别是0.1%和0.05%.对其宏观降解反应动力学的研究表明,X-3B在TiO2、Fe3++TiO2和Ag++TiO2 3种催化剂上的光催化降解动力学均能很好地符合Langmiur-Hinshelwood动力学模型.其表观反应速率常数的大小顺序依次是Ag++TiO2＞Fe3++TiO2＞TiO2;吸附平衡常数则是Fe3++TiO2和Ag++TiO2两者基本相等,两者均比纯TiO2大2～3倍.     

Difference between selenite and selenate in selenium transformation and the regulation of cadmium accumulation in Brassica chinensis

Environmental Science and Pollution Research - Se can regulate Cd accumulation and translocation in plants; however, such effects can be controversial because of the differences in plant species...     

Mechanism of dry detoxification of chromium slag by carbon monoxide

Environmental Chemistry Letters - Dry detoxification is a major technology used at the industrial scale for remediation of chromium slag. However, the mechanism of this reaction is poorly known, in...     

Characterizations of temperature effects on sintered ceramics manufactured with waste foundry sand and clay

The objects of this study were to use waste foundry sand (WFS) to manufacture reclaimed resource tiles and to determine the effects of different kiln temperatures on the properties of the reclaimed WFS tiles. In this study, clay was replaced with 0 or 15 % WFS to manufacture tile specimens. Four different kiln temperatures (1000, 1050, 1100, and 1150 °C) were used in this study for the manufacture of tile specimens. The test results showed that using 15 % WFS in the tile specimens allowed the kiln temperature to be lowered by 50 °C. This temperature reduction is helpful for reducing costs and energy consumption and carbon reduction. Moreover, when the kiln temperature increased from 1000 to 1100 °C and the specimens were placed in acidic and alkaline solutions, the weight loss of the tile specimens containing 15 % WFS was half that of the specimens containing 0 % WFS. The acid-alkali resistance of the tile specimens containing 15 % WFS was also improved. This result suggested that the WFS replacement and kiln temperature affected the properties of the tile specimens.     

Cooperative identification for critical periods and critical source areas of nonpoint source pollution in a typical watershed in China

Environmental Science and Pollution Research - Critical periods (CPs) and critical source areas (CSAs) refer to the high-risk periods and areas of nonpoint source (NPS) pollution in a watershed,...     

Preparation of controlled low-strength materials from alkali-excited red mud-slag-iron tailings sand and a study of the reaction mechanism

Environmental Science and Pollution Research - To address the low utilization of fines in iron tailings sand (IOTs), a controlled low-strength material (CLSM) was prepared from a combination of...     

Analysis of the impact of tourism on agricultural carbon emissions-based on the mediating effect of nonagricultural transfer of labor in China

How to control the growth of agricultural carbon emissions while developing tourism has become the primary issue that needs addressing in the development of rural China. This paper explores the impact of tourism on agricultural carbon emissions and further analyses the mediating effect of labor transfer in this relationship. The analysis is evaluated using provincial panel data from 31 provinces in China from 2007 to 2019 with a sequential regression model. The results show that tourism development increases agricultural carbon emissions, which is more pronounced in areas with advanced economies or higher education levels. Second, labor transfer to nonfarming industries suppresses the increase in agricultural carbon emissions caused by tourism. Finally, (i) the impact of tourism on labor transfer in less developed and less educated regions is limited, and (ii) there is the expectation of large-scale use of agricultural machinery due to labor transfer in economically developed or highly educated areas. The heterogeneity test shows these two reasons lead to a mediating effect of labor transfer on agricultural carbon emissions in different regions.     

Rising greenhouse gas emissions from the China’s aquaculture industry between 2000 and 2020

Environmental Chemistry Letters - Aquaculture is a major source of greenhouse gas emissions, yet long-term spatiotemporal variations of emissions remain poorly documented. Here, we studied methane...