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1.
苏锡常是我国经济飞速发展地区之一,也是重要的粮食生产基地.在快速城镇化背景下,该地区生态环境受到人类活动的强烈冲击,国土空间配置亟待优化.本研究基于多源数据,对苏锡常地区2000~2018年碳储存、食物供给、维持生物多样性3种生态系统服务的时空格局及演变特征进行刻画,并运用双变量空间自相关方法识别了生态系统服务之间的相互关系.结果 表明:(1)整体来看,2000~2018年,苏锡常地区的碳储存服务略有上升,食物供给服务和维持生物多样性服务波动下降;(2)苏锡常地区生态系统服务空间分布严重失衡,表现为中部建成区低,四周自然用地高的分布特点,城镇扩张区各类型生态系统服务退化较为严重;(3)在权衡与协同分析中,碳储存-食物供给服务、碳储存-维持生物多样性服务呈现协同关系,食物供给-维持生物多样性服务呈现权衡关系;(4)各项生态系统服务的权衡与协同关系存在空间差异,低值协同区集中分布在城市中心,高值协同区主要分布在西侧与南侧林地范围,低-高值与高-低值权衡区在空间上呈环绕相间分布.苏锡常地区在未来的发展中需要注意低值协同区和权衡区,有针对性地制定生态保护修复措施,合理调控社会经济发展,实现生态系统服务的协同增效.  相似文献   
2.
Environmental Science and Pollution Research - As a major source of pollution and the cause of climate change, greenhouse gas emissions are attracting the attention of scholars, policymakers, and...  相似文献   
3.
Huang  Ying  Jiang  Qiongji  Yu  Xubiao  Gan  Huihui  Zhu  Xia  Fan  Siyi  Su  Yan  Xu  Zhirui  He  Cunrui 《Environmental science and pollution research international》2021,28(37):51251-51264
Environmental Science and Pollution Research - Trace copper ion (Cu(II)) in water and wastewater can trigger peroxymonosulfate (PMS) activation to oxidize organic compounds, but it only works under...  相似文献   
4.
Chen  Hongqiang  Lin  Lijin  Liao  Ming’an  Wang  Jin  Tang  Yi  Sun  Guochao  Liang  Dong  Xia  Hui  Deng  Qunxian  Wang  Xun  Lv  Xiulan  Ren  Wei 《Environmental science and pollution research international》2019,26(24):24474-24481
Environmental Science and Pollution Research - Grapevine (Vitis vinifera L.) intercropping with floricultural cadmium (Cd) accumulator plants (Helianthus annuus L., Cosmos sulphureus Cav., Cosmos...  相似文献   
5.
水雾除尘效率来源于尘、雾颗粒之间的固-液动态相互作用,从细观角度出发,系统研究水雾液滴与尘堆表面之间的接触、碰撞行为规律.采用高速摄像、图像分析处理技术,从液滴行为、液滴接触角动态变化2个方面研究了液滴在尘堆表面的动态接触行为规律,并对比分析了液滴表面张力、黏度及尘堆粒径对动态接触行为影响的差异.结果表明,液滴在尘堆表面的动态接触行为分为碎裂直接铺展、回缩和回缩反弹3种模式,其接触模式主要取决于粉尘粒径、液滴黏度.在粒径不断减小的尘堆表面,相同理化性质的液滴的行为模式依次为碎裂直接铺展、回缩、回缩反弹.在保证液滴其他性质相同的条件下,增大液滴黏度会导致液滴回缩及回缩反弹行为模式在粉尘粒径较大的尘堆表面提前发生.伴随着液滴黏度增加或尘堆粒径减小,液滴在尘堆表面的接触角会发生动态波动,出现一定数量的波峰和波谷.  相似文献   
6.
Environmental Science and Pollution Research - The photochemical degradation of norfloxacin (NOR) and oxytetracycline (OTC) was investigated under ultraviolet (UV) irradiation. The results...  相似文献   
7.
• Mechanochemical treatment reduced the calcination temperature for biochar synthesis. • Biochar is converted to graphite after mechanochemical treatment. • Biochar was reduced to nanoscale after mechanochemical treatment. Biochar (BC) has been extensively studied as adsorbent for the treatment of water pollution. Despite the distinct advantages, the high calcination temperature and low adsorption capacity of pristine BC limit its practical applications. Most of the former studies focused on the structure and/or surface modification to improve the adsorption capacity of BC. However, the harsh experiment conditions involved in the biochar modification limited the application in industrial level. Herein, we introduced mechanical treatment into BC preparation to reduce the calcination temperature and improve the adsorption capacity simultaneously. The results indicated that the calcination temperature was reduced and the adsorption capacity of the treated BC was improved after mechanochemical treatment. Characterization of the samples disclosed that BCs were graphitized with the particle size reduced to nanoscale after treatment. Adsorption tests indicated that the mechanochemically treated BCs showed much better removal performance of organic contaminants than that of pristine BCs. For instance, among four pristine BCs (BC600, BC700, BC800, and BC900), only BC900 has strong adsorption capacity for MB, while BC600 has low adsorption capacity (1.2 mg/g). By comparison, the adsorption capacity of MB increased greatly to 173.96 mg/g by BC600-500/1 (treated at 500 r/min for 1 hour). To optimize the mechanochemical treatment, the effects of rotation speed and agitation duration were also investigated.  相似文献   
8.
The aims of the present investigation were to reveal the distribution and enrichment characteristics of copper in soil and Phragmites australis of Liao River estuary wetland. The concentrations of copper in root, stem, leaf, and ear of Phragmites australis as well as in soil were determined to study the absorption capacity of copper by wild Phragmites australis of Liao River estuary wetland. The study was carried out at test pool of the Shenyang Agricultural University, and the experimental materials (soil, irrigating water and Phragmites australis) were derived from Liao River estuary wetland. The concentrations of copper in soil and Phragmites australis were 16.4441 to 49.0209 mg/kg and 0.8621 to 89.5524 mg/kg, respectively. The results indicated that the enrichment coefficients of copper in different tissues of Phragmites australis changed with the growth of Phragmites australis. The results revealed that the enrichment coefficients of copper in the whole Phragmites australis were greater than 1 at each growing stage of the Phragmites australis. The results also showed that the transfer coefficients of Phragmites australis to copper changed with the growth of Phragmites australis. The results revealed that the Phragmites australis had a good removal effect on copper from soil and had some characteristics of copper hyperaccumulator.  相似文献   
9.
Land degradation is a global problem that seriously threatens human society. However, in China and elsewhere, ecological restoration still largely relies on a traditional approach that focuses only on ecological factors and ignores socioeconomic factors. To improve the effectiveness of ecological restoration and maximize its economic and ecological benefits, a more efficient approach is needed that provides support for policy development and land management and thereby promotes environmental conservation. We devised a framework for assessing the value of ecosystem services that remain after subtracting costs, such as the opportunity costs, costs of forest protection, and costs for the people who are affected by the program; that is, the net value of ecosystem services (NVES). To understand the difference between the value of a resource and the net value of the ecosystem service it provides, we used data on VES, timber sales, and afforestation costs from China's massive national afforestation programs to calculate the net value of forest ecosystem services in China. Accounting for the abovementioned costs revealed an NVES of ¥6.1 × 1012 for forests in 2014, which was 35.9% less than the value calculated without accounting for costs. As a result, the NVES associated with afforestation was 55.9% less than the NVES of natural forests. In some regions, NVES was negative because of the huge costs of human-made plantations, high evapotranspiration rates (thus, high water opportunity costs), and low forest survival rates. To maximize the ecological benefits of conservation, it is necessary to account for as many costs as possible so that management decisions can be based on NVES, thereby helping managers choose projects that maximize both economic and ecological benefits.  相似文献   
10.
采用臭氧氧化—湿式钙法吸收工艺对模拟烟气进行同时脱硫脱硝处理。O3于150 ℃下具有较高的热稳定性,可将NO氧化为高价态氮氧化物,且NO氧化率随n(O3)∶n(NO)的增大而逐渐提高。烟气中SO2和H2O的存在对NO氧化率的影响不大。O3对SO2的氧化率较低,约为5%。3%(w)石灰石浆液对SO2的吸收率接近100%,NOx吸收率随n(O3)∶n(NO)的增大而逐渐提高,当n(O3)∶n(NO)为1.6时NOx吸收率可达约65%。SO2能促进吸收液对NOx的脱除。石灰石浆液中加入0.2%(w)的(NH42SO3或Na2SO3后NOx吸收率可达约85%或82%,且吸收率随添加剂加入量的增加而提高,添加(NH42SO3的NOx吸收率略高于添加Na2SO3。  相似文献   
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