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1.
Haze is mainly caused by the suspended particulate matters in the air, of which the particulate matters pollution harms leaf vegetables. In this paper, oilseed rapes at four different growing periods were investigated in a simulated particulate pollution environment. In combination of hyper-spectral technology and micro examination, the response of hyper-spectral characteristics of the leaf to particulate matters was investigated in-depth. The hyperspectral, chlorophyll content, net photosynthetic rate and stomatal conductance of leaf were obtained. The deposition and adsorption of particulate matters on the leaf were observed by Environmental Scanning Electron Microscope (ESEM). Normalized difference vegetation index (NDVI), modified red edge normalized (mNDVI705) and modified red edge simple ratio index (mSR705) were selected as characteristic parameters and the range of 510 nm~620 nm as the sensitive band. 16 methods were used to establish the physiological information inversion model. The main results were as follows: Under the influence of particulate matters, the spectral reflectance decreased as a whole. With the increase of leaf age, the phenomenon of blue shift aggravated. The amplitude of yellow and blue edge decreased with overall decreasing vegetation indices. The furrows and irregular band protrusions in leaves were favorable for keeping particulate matters. With longer affecting time and more deposition of particle matters on the leaf, the stomatal opening became smaller. After comparing, principal component regression (PCR) + multiple scatter correction (MSC) + second derivative (SD) + Savitzky-Golay smooth (SG), and partial least square (PLS) + multiple scatter correction (MSC) + first derivative (FD) + Savitzky-Golay smooth (SG) were determined the best method to establish the inversion model of chlorophyll content and net photosynthetic rate respectively. This study may bring novel ideas for the diagnosis and analysis of the physiological response of leaf vegetables under particulate matters pollution using hyper-spectral technology.  相似文献   

2.
亚热带常绿树种对不同粒径颗粒物的滞留能力   总被引:2,自引:0,他引:2  
可吸入颗粒物和细颗粒物是大部分城市的首要污染物,对人体健康和环境都有重要影响;而城市植物能吸附大气颗粒物,进而有效降低大气颗粒物浓度。为了深入探究不同树种叶表面特征与自身滞尘效益之间的关系,该研究以浙江省三种常见城市绿化树种(青冈、冬青、红花檵木)为对象,采用重量法提取各样本在3个粒径上(8~100,2.5~8,0.45~2.5μm)的单位叶面积滞尘量(μg·cm~(-2)),并结合叶面积指数估测全株滞尘量。结果表明:三种供试植物叶片对颗粒物平均单位叶面积滞留量在30.4~63.7μg·cm~(-2)之间,而平均单木滞尘量每株在1.36-9.36 g之间。红花檵木因其叶表粗糙、具有绒毛等特征,对颗粒物(0.45~100μm)有最大的吸附能力(63.74±12.0μg·cm~(-2));对于大颗粒物(8~100μm)和细颗粒物(0.45~2.5μm),三种植物叶片均对其分别具有最大(40.9%~57.5%)、最小(15.6%~20.6%)的吸附能力;对于单木滞尘量,青冈因其具有较大叶面积指数等特征,对颗粒物总吸附效果更佳(每株9.36g)。该研究结果表明城市绿化树种对减缓大气颗粒物污染起到重要作用。  相似文献   

3.
陆地生态系统中水溶性有机质的环境效应   总被引:43,自引:3,他引:40  
黄泽春  陈同斌  雷梅 《生态学报》2002,22(2):259-269
目前水溶性有机质(Dissolved Organic Matter)已逐步成为陆地生态系统中的一个研究热点。系统地评述了陆地生态系统中DOM的组成特点及其环境效应。尽管关于陆地生态系统中DOM的研究还不完善,至今对其性质,组成和分类方法等问题看法不一,但现有结果已经表明DOM是一种十分活跃的重要化学组分,它对陆地生态系统中污染物质的溶解,吸附,解吸,吸收,迁移和生物毒性,微生物活动以及土壤形成过程等均有显著的影响。影响DOM在地生态系统中的环境效应的主要因素包括:DOM与污染物的络合作用,污染物溶解/沉淀作用,土壤对DOM的吸附作用,土壤质地,酸碱缓冲作用等。  相似文献   

4.
不同海滨港湾环境条件下互花米草总黄酮积累动态研究   总被引:1,自引:0,他引:1  
张晟途  钦佩  谢民 《生态学报》1999,19(4):587-590
对两个不同海滨地区的互花米草体内的总黄酮( Total Flavonoids of Spartina alterniflora, T F S)的含量及其随时间和相关环境因子变化进行研究。初步研究结果显示,互花米草 T F S的积累与土壤含盐量呈强正相关关系,与土壤含氮量、土壤有机质呈正相关关系。 T F S的积累是互花米草在高盐度条件下的一种抗逆反应。  相似文献   

5.
Evans J 《Bioethics》2008,22(7):379-387
By concentrating on abortion, the culture wars have avoided facing a crisis about the end of life. This paper explores four themes: (1) the technological transformation of birth and death into matters of decision, not matters of fact; (2) abortion as the nexus of Eros (sex) with Thanatos (death); (3) the real crisis, conveniently masked by our obsession with sex, looming at the end of life, not at its beginning; (4) the surplus-repression that protects us from assuming responsibility for choosing between life and death.  相似文献   

6.
家蝇幼虫抗菌物质组成及其理化性质   总被引:44,自引:2,他引:42       下载免费PDF全文
用抑菌圈、酸碱性聚丙烯酰胺凝胶电泳(PAGE)等方法,对家蝇幼虫免疫血淋巴抗菌物质组成及其理化特性进行了研究。结果表明,家蝇抗菌物质是蛋白质,呈碱性和近中性,由5种成分组成。家蝇抗菌物质有较稳定的理化特性。如对热,对较高浓度盐溶液,较极端的pH溶液,室温放置6h及冻融12次等处理均有较高的稳定性。  相似文献   

7.
《L' Année biologique》1998,37(2):95-105
Viruses are a biological pollution in wastewaters. Their elimination results from treatment processes of polluted effluents in the sewage treatment plant or in the lagooning pilot plant. Bacteriophages are regarded as viruses models and as indicators of faecal contamination. In an expiremental study, two pilot plants laboratories have been used (natural lagooning and activated sludge pilot) to follow and evaluate the elimination rate of somatic coliphage X-174 or the ARN F-specific one MS2. The two phages removal, ranging to 99 % in the two systems, are related with previous values on enteric viruses. The main factors of viral removal and inactivation (adsorption to solid matters, microbial activities, solar radiations, dissolved matters) have been studied too. Adsorption of infectious particles to solid matters is a very significant process. This was obtained in the pilot plant laboratory experiment and in in vitro study (X-174 or MS2 in the presence of the kaolinite or the montmorillonite). Otherwise, 12 hours of solar rays exposition were efficient ro inactivate nearly the whole phagic suspension. The ciliate protozoan Tetrahymena pyriformis does not seem to have an important role for elimination of phages (X-174 and MS2.  相似文献   

8.
蒲公英植株中抗氧化成分的测定和比较   总被引:10,自引:1,他引:10  
本文对蒲公英植株中抗氧化成分进行了分析比较,研究结果表明,蒲公英总抗氧化能力较强,表现在含有丰富的抗氧化物质(类黄酮,异黄酮,Vc等)和抗氧化酶类(SOPD,POD,CAT,GSH-Rx等),根,叶,花序三者比较显示,就抗氧化物质而言,花序中含量最高,叶次之,根最低,而比较其抗氧化酶活性可见,叶中最强,花序次之,根最低,总抗氧化能力同样叶是最强,花序次之,根最低。  相似文献   

9.
明确在常规叶片清洗方法(泡洗或泡洗+刷洗)上增加超声清洗对叶面各径级颗粒物滞纳量定量评估的影响, 并在此基础上研究叶面颗粒物的粒径分布和吸滞效率, 可进一步提高城市树木大气颗粒物吸滞能力的定量评估精度。该文以城市森林建设常用阔叶树种银杏(Ginkgo biloba)和针叶树种油松(Pinus tabuliformis)为研究对象, 于雨后(降水量>15 mm) 4天(短滞尘时长)和14天(长滞尘时长)分别采集叶样, 并依次对其进行泡洗(WC)、刷洗(BC)、超声清洗(UC)等洗脱程序, 然后对每个清洗步骤下叶片洗脱液中颗粒物的质量和粒径分布进行测试, 并依此估算叶片各径级颗粒物的吸滞效率。结果表明, 以“泡洗+刷洗+超声清洗”清洗流程的测试结果为参照, 若只对叶片进行泡洗, 则银杏和油松对大气颗粒物(PM1, 粒径d ≤1 µm)、PM2.5 (d ≤ 2.5 µm)、PM5 (d ≤ 5 µm)、PM10 (d ≤ 10 µm)吸滞量会分别被低估约一半(54%、53%、53%和53%)和40% (42%、42%、42%和42%); 若只进行“泡洗+刷洗”, 则银杏和油松对相应径级颗粒物的吸滞量仍会分别被低估约15% (17%、16%、15%和15%)和20% (21%、20%、20%和20%)。油松叶面颗粒物粒径分布呈双峰曲线, 而银杏叶面颗粒物粒径则呈单峰分布, 且银杏叶面颗粒物平均粒径在短、长滞尘时长下均大于油松。油松叶片对PM1、PM2.5、PM5、PM10和总悬浮颗粒物的吸滞效率分别为8.96、23.92、23.96、23.96和23.96 mg·m-2·d-1, 分别比银杏叶片高112%、73%、34%、37%和42%。  相似文献   

10.
Kumar  Suresh  Dwivedi  Shiv Kumar 《Aerobiologia》2022,38(3):287-327
Aerobiologia - This article provides a brief review of morphological features (MFs), chemical and biological aspects of particulate matters (PMs) and their effects on humans and crops. Based on...  相似文献   

11.
Size matters The size of organisms has multiple consequences, which must not be ignored in all biological inferences of any function, it may concern the organism itself (functional morphology, physiology, reproductive biology), of its environment (autecology) or but to understand the big game we call evolution.  相似文献   

12.
再生水用于地下回灌过程中有机物的迁移和去除   总被引:2,自引:0,他引:2  
人工地下水回灌是解决我国水资源短缺的有效途径之一.在实验室利用土壤柱系统,考查了回灌过程中有机物的迁移和去除.二级处理出水经活性碳吸附后进入土壤柱系统,土壤柱系统对TOC、UV-254和BOD5的去除率分别为44%、34.36%和95%,并且大部分有机物是在土壤表层0~0.5 m被去除的.进水TOC浓度为9~11 mg·L-1时,回灌过程中TOC浓度随土壤柱深度的变化符合指数方程:C=10e-0.6934h(R2=0.8697). 用该方程可以较好地预测土壤柱出水中的TOC浓度.  相似文献   

13.
Researches conducted worldwide indicate a frequent deficiency in mineral matters. Due to the increased need during the period of accelerated growth and development, children belong to the group that is exposed to the highest risk of mineral matter deficiency. Our objectives were to determine the iron, zinc, copper, manganese, and calcium intake in the collective diet of the preschool population in the in the northwestern region of Bosnia- in the Republic of Srpska and to estimate the adequacy of the application of the international food composition tables for nutrition planning relating to mineral matters. Samples of food intended for children’s diet were collected in the preschool institution “Radost” (a kindergarten), in the city of Prijedor. In daily portions, Fe, Zn, Cu, Mn, and Ca contents were determined by flame atomic absorption spectrophotometry. Contents of mineral matters in daily meals were also calculated by the food composition tables. An average daily meal contained 2.86 mg of Fe, 1.71 mg of Zn, 0.19 mg of Cu, 0.21 mg of Mn, and 83.5 mg of Ca. With calculation method, contents of all minerals are significantly higher than the experimental data for all used food composition tables. The obtained results indicate a significant deficiency in mineral matters in the collective diet of the preschool population in the Republic of Srpska, a certain non-compliance with the applicable recommendations, and also suggest a need to create food composition tables for food being consumed in our region.  相似文献   

14.
The global carbon cycle is one of the most important bio-geochemical cycles. Through photosynthesis, green plants absorb CO2 from the atmosphere to produce organic matters, such as sugars, and covert solar energy into chemical energy. The organic matters are then used by all other life forms including humans. When ecosystems and atmosphere are in dynamic equilibrium, the flow of CO2 from the atmosphere into the biosphere because of photosynthesis should be equivalent to the flow of CO2 released back into the atmosphere by respiration. However, during the past century atmospheric CO2 concentration has increased substantially because of the burning of fossil fuels. It is highly likely that the atmospheric increase has resulted in global warming and sea level rise, as suggested by the Intergovernmental Panel on Climate Change (IPCC) .  相似文献   

15.
李组织培养研究进展(综述)   总被引:3,自引:0,他引:3  
本文介绍李茎尖培养、茎段培养、胚培养、原生质体培养及叶片培养,分析其中的有关影响因子,重点阐述不同碳源和外源附加物对试管苗生长和分化的影响,并提出李组织培养的存在问题及解决途径。  相似文献   

16.
非点源污染物在沟渠湿地中的累积和植物吸收净化   总被引:21,自引:0,他引:21  
对有机质和总氮在沟渠湿地底泥中的垂直分布和水平分布的研究表明,40 cm以下深度的芦苇(Phragmites communis)和茭草(Zizania latifolia)湿地底泥对有机质和总氮有显著的持留和累积作用;但表层底泥中含量随季节变化大,最高与最低值相差近2倍以上.有机质和总氮之间有极显著的相关关系,在芦苇和茭草湿地底泥中的相关系数分别为0.9876和0.9335.水体中总氮与NH4+-N和NO3-N也显著相关,表明总氮的主要成分是有机氮,其矿化作用是无机氮的重要来源.每年秋季芦苇收割以后,可带走氮818 kg·hm-2和磷103.6 kg·hm-2,茭草可带走氮131 kg·hm-2和磷28.9 kg·hm-2.茭白对氮的吸收能力高,试验表明,利用茭白取代野生植物,既能取得很好的净化效果,又可被农民主动回收,解决植物的二次污染问题.  相似文献   

17.
Dynamic responses of brain tissues are needed for predicting traumatic brain injury (TBI). We modified a dynamic experimental technique for characterizing high strain-rate mechanical behavior of brain tissues. Using the setup, the gray and white matters from bovine brains were characterized under compression to large strains at five different strain rates ranging from 0.01 to 3000/s. The white matter was examined both along and perpendicular to the coronal section for anisotropy characterization. The results show that both brain tissue matters are highly strain-rate sensitive. Differences between the white matter and gray matter in their mechanical responses are recorded. The white matter shows insignificant anisotropy over all strain rates. These results will lead to rate-dependent material modeling for dynamic event simulations.  相似文献   

18.
The Kaschin-Beck Disease, an endemic disease in China, occurs in low-selenium areas. Using human embryonic cartilage cell as a system, the effect of selenite and another etiological factors, such as, organic matters in water, and grain from disease regions, were studied. It was shown that Se(IV), as well as superoxide dismutase, could prevent the cells from damage by organic matters, and increase the activity of GSHpx and decrease the production of lipid peroxide. A model test of adrenalin autooxidation was carried out, and it was found that the oxy-radical can be eliminated by Se(IV). Thus, it was assumed, that selenium was a protective factor and free radical scavenger for Kaschin-Beck Disease.  相似文献   

19.
富营养湖泊滇池水华蓝藻的机械清除   总被引:37,自引:2,他引:35  
富营养湖泊暴发蓝藻水华时可集聚浓度达n× 10 8— 9cell/L ,利用重力振动、旋振和离心等方法收集富藻水 ,逐次浓缩、脱水后得藻泥 ;根据需要可对藻泥进行干燥 ,得到干藻粉。 2 0 0 1年 4月至 2 0 0 2年 11月在云南滇池以上述方式清除蓝藻水华 35 1d ,共处理富藻水 4 2 6 4 8m3 ,折合清除水华蓝藻干重为 4 6 0 .83t。按所清除的蓝藻干粉的总氮、总磷、总钾、粗有机质及重金属的平均含量计算 ,相当于从试验区水体中去除了氮 (N) 37.33t、磷 (P) 2 .71t、钾 (K)2 .4 9t及粗有机质 2 0 0 .32t;重金属铅 (Pb) 2 .2 89kg、砷 (As) 2 .2 3kg、汞 (Hg) 2 .3kg、镉 (Cd) 0 .5 1kg。表明在富营养湖泊中水华蓝藻大量暴发时 ,采用机械除藻 ,对控制蓝藻水华污染 ,有效降低内源氮、磷等污染物负荷具有十分重要的作用  相似文献   

20.
城市垃圾堆肥及其复合肥对黑麦草草坪质量的影响   总被引:12,自引:2,他引:10  
为加速城市生活垃圾堆肥农业资源化利用研究,避免重金属等有害物质进入食物链,利用盆栽试验,研究了垃圾堆肥及以其为原料研制而成的3种复合肥的不同施肥水平对土壤肥力,黑麦草生长及草坪质量的影响,以选取最佳的适合黑麦草生长的垃圾肥料及其施用量。共设空白、堆肥、化肥、复合肥1、复合肥2、复合肥3等6个处理,每个处理又分为高、中、低3种施肥水平,测试草坪生物指标的质量状况和土壤肥力。结果表明:与化肥比较,垃圾复合肥可以显著提高土壤有机质、全氮、碱解氮、全磷的含量。垃圾复合肥明显促进了黑麦草的茎与根系的生长,提高了生物量,改善了叶片的色泽和整齐度,提高了草坪的密度和质量;促进了黑麦草对氮的吸收,尤其是生长后期,叶片中氮和叶绿素的含量明显高于化肥与空白处理,且差异显著。草坪质量综合评价以垃圾复合肥1的中量施肥处理为最好,黑麦草分蘖最高,地上生物量适度;除复合肥的高量施肥处理外,复合肥1的中量施肥处理茎叶中氮素和叶绿素含量最高,草坪品质最高。  相似文献   

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