Hydroelectricity production and forest conservation in watersheds.

Globally, particularly in developing countries, hydroelectricity production and economic growth occur together with ecosystem/biodiversity conservation in watersheds. There is a relationship between hydroelectricity production and ecosystem/biodiversity conservation in watersheds, centering on the supply and demand for ecosystem services of river water flow regulation and sediment retention. Here we show that, in the upper reach of the Yangtze River, hydroelectricity production of Three Gorges Hydroelectric Power Plant can form a beneficial relationship with forest conservation through the paid use (compensating residents for their cooperation in the conservation) of ecosystem services launched by the National Natural Forest Protection Project. This interaction can provide additional incentives to encourage local communities' long-term cooperation in conserving and protecting the restored forest ecosystems. Hydroelectricity plants also obtain benefits from this interaction. The industrialization of ecosystem services supply provides an operational framework for this beneficial interaction. Sustainable forest ecosystem conservation will require developing new institutions and policies and must involve local communities in the conservation and protection of their local forests.     

西南部分地区麻疯树种子油的理化性质及脂肪酸组成分析

从西南6个地区采集了麻疯树种子并分析比较了其生物学性状和种子油的理化性质及脂肪酸组成.所有样品的百粒重范围为41.80~71.39g,出仁率60.02%~81.43%,种仁含油率51.76%~57.93%,种子含油率31.07%~47.17%,不饱和脂肪酸含量74.89%~79.68%.其中永胜产麻疯树的种子品质最好,其出仁率为81.43%,种仁含油率57.93%,种子含油率47.17%,不饱和脂肪酸含量79.68%.攀枝花和宁南产麻疯树的种子品质次之.双柏和罗甸麻疯树的种子油酸值为0.81,在所有样品(0.81~9.46)中最低.对麻疯树种子及种子油性质的相关数据进行方差分析,结果表明,产地不同,麻疯树种子的生物学性质、种子油理化性质和脂肪酸组成都有一些差异.图2表3参18     

湖南烟区烤烟锌含量与土壤有效锌的分布特点及关系分析

采用野外调查和室内分析相结合的方法,研究了湖南烟区烤烟锌含量与土壤有效锌含量的分布特点及关系。结果表明,(1)湖南烟叶锌含量总体适宜,平均为(36.30±14.05)mg·kg-1,变幅为10.50~100.50mg·kg-1;调查区域内有92.58%的烟叶样本锌含量落在20.00~80.00mg·kg-1区间内;不同等级烟叶锌含量的规律是:B2F>C3F>X2F。(2)湖南植烟土壤有效锌含量适中,平均为(2.27±3.74)mg·kg-1,变幅为0.13~62.59mg·kg-1,变异系数高达155.09%;有22.41%的土壤样本在不同程度上缺锌(≤1.00mg·kg-1),有7.36%的样本的有效锌含量超过4.00mg·kg-1,满足优质烟生长的土壤样本达到70.23%;不同土壤类型有效锌含量的变化规律是:鸭屎泥>黄泥田>黄灰土>黄壤土。(3)烟叶锌含量与土壤有效锌含量呈极显著正相关,相关系数为0.312;与土壤有效铜、有效铁和有效硫均呈极显著正相关,与土壤pH值、有效钾和水溶性氯均呈显著负相关。(4)在土壤有效锌含量分组后,不同等级烟叶锌含量均随着土壤有效锌含量的增加,而呈现先增加后下降的趋势,且各等级烟叶锌含量在组间差异达到5%的显著水平。     

长江上游径流量变化及其与影响因子关系分析

利用长江上游直门达水文站1963～2001年径流量及同期该流域气象资料,分析了长江上游径流量变化规律及其影响因子。研究表明:近40年来长江上游径流量呈减少趋势,其中以秋季径流量减少最为明显;长江上游流域夏季降水量减少、年平均气温升高和蒸发增大引起的气候干旱化趋势是造成径流量减少的主要原因,其中降水量是影响径流量的最主要因子;夏季降水量的减少与秋季径流量的减少关系密切,而秋季径流量的减少最终影响到了年径流量的减少。     

Robust magnetic laccase-mimicking nanozyme for oxidizing o-phenylenediamine and removing phenolic pollutants

In this study, we report a novel magnetic biomimetic nanozyme(Fe_3O_4@Cu/GMP(guanosine5′-monophosphate)) with high laccase-like activity, which could oxidize toxic ophenylenediamine(OPD) and remove phenolic compounds.The magnetic laccase-like nanozyme was readily obtained via complexed Cu~(2+)and GMP that grew on the surface of magnetic Fe_3O_4 nanoparticles.The prepared Fe_3O_4@Cu/GMP catalyst could be magnetically recycled for at least five cycles while still retaining above 70% activity.As a laccase mimic,Fe_3O_4@Cu/GMP had more activity and robust stability than natural laccase for the oxidization of OPD.Fe_3O_4@Cu/GMP retained about 90% residual activity at 90℃ and showed little change at pH 3–9, and the nanozyme kept its excellent activity after long-term storage.Meanwhile, Fe_3O_4@Cu/GMP had better activity for removing phenolic compounds, and the removal of naphthol was more than 95%.Consequently, the proposed Fe_3O_4@Cu/GMP nanozyme shows potential for use as a robust catalyst for applications in environmental remediation.     

酸和热处理对海泡石结构及吸附Pb2+、 Cd2+性能的影响

通过X射线衍射、傅里叶变换红外光谱及比表面积分析等研究了酸和热处理对天然海泡石结构的影响,并考察不同处理后的海泡石样品吸附重金属Pb2+、Cd2+性能.结果表明,海泡石比表面积均随盐酸浓度、处理时间的增加而略有增大,而结构无明显变化,0.5 mol·L-1 HCl处理时,天然海泡石中的CaCO3未能被完全去除,6.0 mol·L-1 HCl处理72 h时,海泡石比表面积达到最大301.47 m2·g-1.盐酸热处理并不能提高海泡石的比表面积,也不会使海泡石结构产生明显变化.不同类型酸处理对海泡石比表面积提高顺序依次为:HCl>HNO3>H2SO4;海泡石经焙烧后比表面积迅速下降,由100℃的21.44 m2·g-1下降到900℃的0.17 m2·g-1.重金属吸附实验表明,盐酸处理浓度和时间对海泡石吸附Pb2+、Cd2+离子性能无明显影响;不同酸处理对海泡石吸附Pb2+、Cd2+离子性能存在一定影响,H2SO4处理后海泡石对Pb2+、Cd2+离子吸附量明显高于HCl和HNO3处理.海泡石焙烧处理后对Pb2+离子吸附量无明显影响,但对Cd2+离子吸附量在焙烧700℃以上时增加明显.     

2014~2017北京市气象条件和人为排放变化对空气质量改善的贡献评估

2014～2017年北京地区霾日数和污染日数逐年减少,PM_(2.5)、PM_(10)、SO_2和NO_2年平均质量浓度下降,污染程度缓解,采暖期中的11～12月尤为明显.针对空气质量的显著改善,从气象条件的改善和减排措施两方面进行探讨分析,并结合数值模式和大数据挖掘技术实现气象和排放对大气污染贡献率的定量化研究.结果表明,2017年与过去3 a相比,平均风速增加7. 9%,≥3. 4 m·s~(-1)的风速频次最高(10. 6%),≥70%湿度日占比最小(25. 1%);其中,采暖期与过去3 a同期相比,小风日数减少8. 6%、大气环境容量指数和通风指数平均增加约11%,边界层高度以3. 2%·a~(-1)的速率升高,尤其11～12月各要素改善更显著,且该时段内2014年各因子变化与2017年相似.非采暖期(4～10月)累积降水量558. 3 mm,仅次于2016年,有利于污染物的清除和湿沉降.利用WRF-CHEM对霾和污染频发的12月进行模拟发现,气象要素的改变导致2017年12月北京PM_(2.5)质量浓度较2014～2016年同期分别降低5%、38%和25%.因缺少政府实际施行的减排方案,无法利用WRF-CHEM量化气象和减排的具体贡献率,因此借助大数据挖掘算法,基于K近邻算法(KNN)和支持向量机(SVM)模型对气象和减排对空气质量改善的贡献进行评估,结果显示2017年减少的霾日和重污染日,65. 0%归因于减排的贡献,35. 0%归因为气象条件的改善.可见,气象与生态环境部门应继续加强数据开放共享,科学开展气象条件预报与减排评估.     

Identification of soil heavy metal sources from anthropogenic activities and pollution assessment of Fuyang County, China

Understanding regional variations of soil heavy metals and their anthropogenic influence are very important for environmental planning. In this study, 286 surface soil samples were collected in Fuyang county, and the 'total' metals for copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd) and nickel (Ni) were measured in 2005. Statistic analysis showed that Cu, Zn, Pb and Cd had been added by exterior factors, and Ni was mainly controlled by natural factors. The combination of multivariate statistical and geostatistical analysis successfully grouped three groups (Cu, Zn and Pb; Cd; and Ni) of heavy metals from different sources. Through pollution evaluation, it was found that 15.76% of the study area for Cu, Zn and Pb, and 46.14% for Cd suffered from moderate or severe pollution. Further spatial analysis identified the limestone mining activities, paper mills, cement factory and metallurgic activities were the main sources for the concentration of Cu, Zn, Pb and Cd in soils, and soil Ni was mainly determined by the parent materials.     

硅藻土强化混凝去除微污染原水中的有机物

研究了联用硅藻土与聚合氯化铝（PAC）强化混凝对有机微污染原水中不同性质溶解性有机物的去除效果。采用超滤膜和XAD系列树脂对微污染原水中溶解性有机物进行分级表征,物理分级表明分子量〈4 kD的溶解性有机物占50%以上,化学分级表明原水中以憎水酸（HoA）和亲水物质（HiM）为主。硅藻土助凝去除溶解性有机物,实验结果表明,当PAC投加量30 mg/L,硅藻土投加量0.5 g/L时,溶解性有机碳去除率由22.5%提高到26.3%。     

Monitoring and identification of spatiotemporal landscape changes in multiple remote sensing images by using a stratified conditional Latin hypercube sampling approach and geostatistical simulation

This study develops a stratified conditional Latin hypercube sampling (scLHS) approach for multiple, remotely sensed, normalized difference vegetation index (NDVI) images. The objective is to sample, monitor, and delineate spatiotemporal landscape changes, including spatial heterogeneity and variability, in a given area. The scLHS approach, which is based on the variance quadtree technique (VQT) and the conditional Latin hypercube sampling (cLHS) method, selects samples in order to delineate landscape changes from multiple NDVI images. The images are then mapped for calibration and validation by using sequential Gaussian simulation (SGS) with the scLHS selected samples. Spatial statistical results indicate that in terms of their statistical distribution, spatial distribution, and spatial variation, the statistics and variograms of the scLHS samples resemble those of multiple NDVI images more closely than those of cLHS and VQT samples. Moreover, the accuracy of simulated NDVI images based on SGS with scLHS samples is significantly better than that of simulated NDVI images based on SGS with cLHS samples and VQT samples, respectively. However, the proposed approach efficiently monitors the spatial characteristics of landscape changes, including the statistics, spatial variability, and heterogeneity of NDVI images. In addition, SGS with the scLHS samples effectively reproduces spatial patterns and landscape changes in multiple NDVI images.