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1.
废旧橡胶颗粒填充草坪根带基质及草坪植物生态响应   总被引:4,自引:0,他引:4  
选择4种不同粒径大小的废旧橡胶颗粒分别与壤土、粘土、沙土组配草坪基质,通过组配基质构建草坪建植体系,研究了草坪植物的生态响应。通过对各生态指标综合效应分析,结果表明:壤土组配基质中,胶粒粒径为0.5~1 mm与4~6 mm组配基质要好于1~2 mm和2~4 mm组配基质;粘土组配基质中,1~2 mm胶粒组配基质为最好;对于沙土组配基质,1~2 mm和2~4 mm粒径的胶粒组配基质要优于0.5~1 mm与4~6 mm的组配基质。比较发现,从草坪植物生长角度来看,以沙土填充废胶粒为介质组配运动场草坪基质具有较好的应用前景。  相似文献   

2.
践踏填充废胶粒基质草坪黑麦草特征物质与光合性能   总被引:1,自引:0,他引:1  
通过践踏胁迫基质填充废胶粒草坪,研究了黑麦草粗纤维、可溶性糖、叶绿素、气孔导度、细胞间CO2浓度、净光合速率及蒸腾速率等指标,结果表明:基质填充不同粒径胶粒草坪践踏后,1~2 mm粒径处理黑麦草粗纤维含量低于2~4 mm和4~6 mm处理,对照为最高.叶绿素含量差异较为明显,其大小顺序为1~2 mm>2~4 mm>4~6 mm>对照.可溶性糖含量差异显著,其中1~2 mm粒径处理为最高,然后依次为2~4 mm、4~6 mm及对照.净光合速率以1~2 mm处理最大,对照最小,二者差异显著(P<0.05);气孔导度的变化幅度也以1~2 mm为最大,其细胞间CO2浓度则明显降低,表明1~2 mm粒径胶粒基质体系的光合能力比其它处理都强.综合分析说明,草坪基质填充废胶粒的粒径与草坪耐践踏性具有相关性,在本研究中基质填充1~2 mm粒径胶粒的草坪耐践踏性能要明显优于其它2个处理.  相似文献   

3.
为了了解香附有效成分对小麦种子萌发和幼苗生长的影响,采用室内培养皿培养法,分析不同浓度的香附浸提液浸种后对小麦种子发芽率、发芽指数、活力指数及幼苗高度、根长、根数、整株鲜重及干重等指标的影响。结果表明,香附浸提液对小麦种子的萌发及幼苗的生长有明显抑制作用,抑制作用随着香附浸提液浓度的增加,抑制效果增强,与浸泡蒸馏水的对照相比,香附浸提液浸种处理显著降低了小麦的种子发芽率、发芽指数、种子活力、苗高、根长、植株鲜重和干重。  相似文献   

4.
以带内生真菌(E+)和不带内生真菌(E-)的多年生黑麦草(Lolium perenne)种子为材料,采用室内种子萌发实验,分析多年生黑麦草在不同pH(4.47~6.12)砖红壤浸提液中种子萌发、幼苗形态指标及生理指标的变化,探讨内生真菌对酸性环境中多年生黑麦草幼苗生长和生理特性的影响。结果表明:(1)在相同带菌情况下(内生真菌侵染E+或未浸染E-),随着砖红壤浸提液pH值的降低(浸提液酸性的增强),E+和E-种子发芽率、发芽势、发芽指数、活力指数、胚芽长、胚根长、胚芽鲜重和胚芽干重均表现为逐渐下降的趋势,且5个砖红壤浸提液处理均显著低于相应对照(CK,pH 6.12);幼苗脯氨酸含量、超氧化物歧化酶活性、过氧化物酶活性和丙二醛含量呈上升趋势,且5个砖红壤浸提液处理均显著高于相应CK。(2)除CK外,在相同pH砖红壤浸提液处理下,内生真菌侵染显著提高了多年黑麦草的发芽率、胚芽长、鲜重和干重等形态指标及脯氨酸含量和超氧化物歧化酶活性,却显著降低了过氧化物酶活性和丙二醛含量;在砖红壤浸提液pH为4.47~6.12时,E+萌发种子胚根长与E-之间无显著差异。研究发现,不同pH砖红壤浸提液对E+和E-种子萌发、生长和生理有一定的影响,内生真菌的侵染可促进宿主植物的生长,同时对砖红壤浸提液pH值具有较宽的适应范围,可将多年生黑麦草内生真菌共生体应用于酸性土壤改良。  相似文献   

5.
生活垃圾堆肥淋洗液培植无土草皮的生态特征   总被引:2,自引:0,他引:2  
多立安  廉菲  赵树兰  滕萌  王礼莉  高玉葆 《生态学报》2007,27(12):5050-5056
以生活垃圾堆肥淋洗液培植无土草皮,结果表明,垃圾堆肥淋洗液中有机质、全氮、有效磷及其它营养元素含量显著高于对照土壤淋洗液,能够充分满足草坪植物生长需要。高浓度淋洗液使黑麦草和高羊茅种子萌发高峰期推迟出现,但不影响发芽率,到萌发第11天,种子发芽率分别达到94%和92%以上。对黑麦草而言,80%的淋洗液可显著提高植株高度、地上生物量和叶绿素含量;对高羊茅,60%的淋洗液则为最佳浓度。当淋洗液培植的无土草皮进行田间铺坪90d时,黑麦草和高羊茅草皮地上生物量分别达到5.38g/块和7.89g/块,并显著高于对照草皮(P〈0.05),而地下生物量和根长差异不显著。垃圾堆肥淋洗液改变了黑麦草和高羊茅植株地上/地下生物量的分配格局,使其根冠比降低,其分别为4.60和3.71,并明显低于对照。从坪用性状上看,铺坪后垃圾堆肥淋洗液培养的草皮叶色深绿,质地柔软光滑,明显优于土壤淋洗液培养的对照草皮。  相似文献   

6.
垃圾堆肥基质对不同草坪植物生态及质量特征的影响   总被引:1,自引:0,他引:1  
赵树兰  廉菲  多立安 《生态学报》2011,31(6):1742-1748
通过田间实验,研究了城市生活垃圾堆肥基质对高羊茅和黑麦草不同品种草坪植物生态及质量特征的影响。结果表明:堆肥能明显促进草坪植物生长,提高地上和地下生物量。与一茬草相比,垃圾堆肥对二茬草的促进作用更为明显,说明了垃圾堆肥营养具有缓释效应。另外,垃圾堆肥能加快草坪植物返青,对越年草坪植物盖度、株高以及生物量具有明显促进作用。不同品种草坪植物对垃圾堆肥的生长响应存在明显差异,在生长速度和生物量指标上,3种高羊茅品种表现较好。采用美国国家草坪评比体系NTEP(9分法)作为评比标准,对各草坪综合质量进行评定。结果垃圾堆肥建植的草坪综合质量均明显好于对照;不同草坪植物之间比较,以爱神综合质量为最佳,尤其表现在密度、颜色和质地方面。  相似文献   

7.
以滤纸生测方法测定了麦冬(Ophiopogon japonicus)不同部位去离子水浸提液对黑麦草(Lollum multiflorum)、紫云英(Astragalus sinicus)、菜心 (Brassica parachinensis)、萝卜 (Raphanus sativus)以及三叶鬼针草(Bidens pilosa)等几种南方常见植物种子萌发和幼苗生长的化感效应, 结果表明低浓度麦冬水浸提液促进了受体种子萌发和幼苗根长, 而高浓度则均表现出抑制作, 水提液的浓度越高抑制效果越强。水提液对萝卜幼苗苗高和生物量均表现出显著的化感促进作用 , 而高浓度的麦冬地上部水提液对黑麦草、紫云英和三叶鬼针草幼苗的株高和生物量存在显著化感抑制作用。且麦冬不同部位水浸提液对同一受体的化感效应强度有差异, 地上部水浸提液化感作用强于地下部分。  相似文献   

8.
测定了宁夏黄土丘陵区植被恢复近30年的天然草地和农地不同粒径团聚体的土壤养分含量、微生物生物量、呼吸特性和生态化学计量比等指标,探索黄土丘陵区植被恢复对不同粒径土壤团聚体的养分特性和微生物学性质的影响.结果表明: 微团聚体(粒径<0.25 mm)质量百分比、各粒径土壤团聚体养分(有机碳、全氮、速效钾)含量、C/N均表现为天然草地大于农地,其中1~2 mm粒径团聚体有机碳、全氮含量在天然草地和农地中均最高,C/N也较高,说明植被恢复能有效促进土壤团粒的形成,适宜养分积累和有机碳的汇集,且在1~2 mm粒径团聚体上表现最为突出;天然草地各粒径土壤团聚体微生物生物量(碳、氮)、基础呼吸强度均高于农地,而呼吸熵低于农地,可见植被恢复措施可有效提高各粒径土壤微生物生物量与活性,并使土壤生境趋于稳定;但由于养分特性的差异,不同粒径团聚体微生物特性对植被修复的响应存在差异,其中天然草地土壤1~2 mm粒径团聚体微生物生物量碳,<0.25、0.25~1、1~2 mm粒径团聚体微生物生物量氮,以及1~2、>5 mm粒径团聚体基础呼吸强度显著高于其他粒径,即上述粒径团聚体的微生物生物量和微生物活性在植被恢复过程中逐渐被改善.表明宁南山区植被恢复有效改善了土壤团聚体的肥力状况与结构特征,且1~2 mm粒径团聚体的改良效果最为突出.  相似文献   

9.
杨树根系浸提液对3种牧草种子萌发及幼苗生长的影响   总被引:4,自引:0,他引:4  
采用不同浓度(3、10和30mg/mL)的南林95杨〔PopulusdeltoidsBartr.cv.Lux×P.euramericana(Dode)Guineircv.I 45/51〕和NL 80351杨(P.deltoidsBartr.cv.Lux×P.deltoidsBartr.cv.Harvard)根系浸提液,处理杨树 牧草复合经营系统中3种主要牧草种子,探讨杨树根系浸提液对牧草种子萌发及幼苗生长的影响。结果表明:南林95杨和NL 80351杨根系浸提液对3种牧草种子的萌发及幼苗的生长有一定影响。这2个无性系根系浸提液对紫花苜蓿(MedicagosativaL.)、白三叶(TrifoliumrepensL.)和杂交狼尾草(PennisetumalopecuroidesL.×P.americanumL.)的种子发芽率、幼苗高生长、根长生长及种子活力主要表现为抑制作用,在浓度较高时影响尤为明显;但2个无性系根系浸提液对白三叶的高生长(南林95杨30mg/mL除外)表现出一定的促进作用;在3mg/mL浓度时,2个无性系根系浸提液对白三叶的种子活力也有一定的促进作用。  相似文献   

10.
多立安  张玥含  赵树兰 《生态学报》2008,28(10):4765-4770
通过在添加蚯蚓的生活垃圾堆肥基质上培植黑麦草、高羊茅和早熟禾,测定了草坪植物生物量、丙二醛(MDA)含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性,研究了蚯蚓活动对3种草坪植物生长和抗氧化酶系的影响。结果表明:蚯蚓活动使黑麦草、高羊茅的地上牛物量分别增加了3.53倍和12.17倍,地下生物量分别增加127.45%和148.94%,而早熟禾地上生物量减少42.37%。放入蚯蚓后,黑麦草和高羊茅的MDA含量分别减少了51.30%和87.52%,早熟禾增加了16.74倍。黑麦草、高羊茅和早熟禾的SOD和POD活性在放入蚯蚓后,分别有所下降,SOD活性分别下降了64.93%,13.38%和83.56%,POD活性分别下降41.15%,54.41%和34.09%。黑麦草CAT活性提高了5.61%,而高羊茅和早熟禾分别下降11.73%和33.23%。可见,生活垃圾堆肥草坪中蚯蚓活动对植物生长及抗氧化酶系的影响因植物种类而异。  相似文献   

11.
Domestic rubbish compost is a complex-polluted system, containing multiple heavy metals,which limits its application. In the present study, Cr, Mn, Ni, Cu, Zn, Cd, and Pb accumulation and ecological responses of turfgrass to rubbish compost were investigated following the addition of EDTA. The results showed that the addition of EDTA significantly increased heavy metal accumulation in Lolium perenne L.and Festuca arundinacea L. Most heavy metal concentrations in L. perenne increased with increasing EDTA supply. The concentrations of Cr, Mn, Ni, Cu, and Cd in L. perenne were highest following the addition of 30 mmol/kg EDTA and the concentrations of Cr and Ni at this point reached concentrations of1914.17 and 521.25 μg/g, respectively. When the EDTA level was < 20 mmol/kg, the accumulation of most heavy metals in F. arundinacea increased with increasing EDTA supply, but showed a tendency to decrease at EDTA concentrations >20 mmol/kg. The highest concentrations of Mn, Ni, Cu, and Zn in F.arundinacea reached 268.01, 110.94, 161.52 and 1 354.97 μg/g, respectively, following the addition of 20mmol/kg EDTA. The EDTA-induced increase in the accumulation of heavy metals in turfgrass was plantand metal-specific. L. perenne had a relatively high ability to accumulate Cr, Ni, and Zn. The highest Zn concentration was 2 979.58 μg/g and, following the addition of EDTA, the concentrations of the three metals were increased 26.23, 20.03, and 10.49-fold, respectively, compared with control. However, F. arundinacea showed a high ability to accumulate Cr, with the highest concentration (596.02 μg/g) seen following the addition of 30 mmol/kg EDTA; the concentration of Cr increased 15.51-fold compared with control. With EDTA addition, ecological responses of both turfgrass species showed that EDTA at concentrations <10mmol/kg increased seed germination and aboveground net primary production (ANP) of L. perenne and slightly inhibited those of F.arundinacea, but EDTA at concentrations >20 mmol/kg inhibited these parameters significantly for both species. Moreover, EDTA increased the chlorophyll and proline content at all concentrations tested. On the basis of the synthetic remediation index, the optimal EDTA concentration for turfgrass remediation of heavy metals in compost is approximately 10 mmol/kg.  相似文献   

12.
设置移栽时营养杯的有无及其大小作试验,研究长喙田菁在乐昌铅锌矿强酸化尾矿上的生长、固氮和积累重金属情况。结果表明,强酸性(pH<3)是限制植物定植的主要因素,在pH=5-7情况下,长喙田菁能在该尾矿库中定植、生长和固氮,表现出良好的适应性。未带营养杯移栽的长喙田菁在尾矿上生长84d,其株高117cm、茎基部直径1.35cm、单株生物量(干物质)20.2g、单位面积生物量(干物质)2828kghm-2、氮素积累量40kghm-2;带营养杯移栽的上述各指标分别达到140-144cm、1.59-1.68cm、36.6-38.8g、5124-5432kghm-2和77-107kghm-2,均显著高于未带营养杯处理的。长喙田菁根部铅、锌、铜、镉含量均最高,其次为茎,叶中最低;长喙田菁的4种重金属积累量为锌(186-221mgkg-1)>铅(96-145mgkg-1)>铜(17-30mgkg-1)>镉(3-4mgkg-1)。带营养杯移栽能有效提高长喙田菁的产量和氮积累量,且明显降低其体内的重金属含量。试验证明长喙田菁是较理想的铅锌矿尾矿废弃地植被重建的先锋植物。  相似文献   

13.
赵树兰  多立安 《广西植物》2008,28(1):100-106
采用砂培法,研究了匍茎翦股颖对Cu2+、Zn2+、Cd2+与Pb2+胁迫的生长响应及阈限浓度,结果表明:种子萌发率随着4种重金属浓度的增加而下降。对株高的影响是当重金属浓度小于100mg/L时会促进株高生长,高于100mg/L则产生抑制作用。Cu2+显著抑制根系生长,并随浓度的增加抑制效应愈加显著;在Cu2+浓度为600mg/L时匍茎翦股颖的根长比对照下降了93.75%。Cu2+、Zn2+、Pb2+浓度小于200mg/L时会促进地上生物量的增加,但高于200mg/L时,地上生物量会随着3种重金属的增加而减少。Cu2+、Zn2+浓度小于100mg/L或Cd2+、Pb2+浓度小于200mg/L会增加叶绿素的含量,高浓度会降低叶绿素的含量;Cd2+在浓度为600mg/L时显著降低叶绿素含量,与对照相比,下降了43.55%。匍茎翦股颖生长的综合效应分析表明,匍茎翦股颖对Cu2+胁迫最敏感,具有较低的阈限浓度,而Zn2+胁迫对匍茎翦股颖的生长影响最小,阈限浓度相对较高。  相似文献   

14.
研究了喀斯特乡土树种伊桐的果实性状、种子性状、播种萌发和幼苗生长等的基本特征。结果表明:伊桐果实单果鲜重63.20~149.50g,其长度和宽度则分别为55.59~86.60mm和38.59~51.80mm,单果出种量19.95~57.15g,出籽率31.57%~40.81%,单果种子数343~690粒,单粒种子均重0.0582~0.0857g,其出籽率、单果种子数和单粒种子均重与果实重量存在一定程度的正相关;伊桐种子的长、宽平均分别为(25.93±2.80)mm和(13.72±2.88)mm,完整种子平均风干重(0.0153±0.0033)g,脱翅种子平均重(0.0112±0.0024)g,种翅占整个种子的(26.56±4.53)%;伊桐种子播前采取不同处理方式的平均发芽天数、平均发芽指数和平均发芽率等存在一定或是比较明显的差异,浸种、脱翅或两者相结合的方式均能有效缩短种子发芽时间并明显提高种子发芽率;伊桐幼苗的株高和基径的月均生长量分别介于3.3~16.3cm和0.32~2.80mm之间,其中经浸种处理的前期生长较快,未经浸种处理的中期生长较快。  相似文献   

15.
研究不同污泥堆肥施用量(0、0.8%、2%、6%和10%)对高羊茅、黑麦草和早熟禾3种草坪草生长及光合特征的影响.结果表明: 污泥堆肥施用量为6%时效果最好.随污泥堆肥施用量的增加,高羊茅、黑麦草和早熟禾的株高、单叶面积和单株生物量均显著增加,根冠比显著降低,其中,株高增幅分别为64.9%~180.8%、97.3%~200.9%和39.1%~156.5%,单叶面积增幅分别为91.3%~417.4%、186.4%~394.9%和164.6%~508.3%,单株生物量增幅分别为333.4%~867.6%、138.4%~445.1%和316.3%~669.2%.随污泥堆肥施用量的增加,高羊茅净光合速率(Pn)、胞间CO2浓度(Ci)、蒸腾速率(Tr)和水分利用效率(WUE)呈先增加后降低的趋势;早熟禾Pn、Tr和WUE逐渐增加,Ci呈先增加后降低的趋势;黑麦草Pn和WUE逐渐增加,但其Ci和Tr呈先增加后降低的趋势.污泥堆肥施用使3种草叶绿素a、b和(a+b)含量增加,施用量>6%后叶绿素a、b和(a+b)含量下降,但叶绿素a/b变化不明显.
  相似文献   

16.
研究了十二烷基苯磺酸钠(SDBS)、十六烷基三甲基溴化铵(CTAB)、聚乙二醇辛基苯基醚(TritonX-100)等不同离子类型的表面活性剂对水稻土中重金属的解吸效果,并采用盆栽实验研究了上述3种表面活性剂对Zn超富集植物长柔毛委陵菜(Potentilla griffithii var. velutina)的生物量、吸收和富集重金属的影响.结果表明:CTAB对水稻土中Zn、Pb、Cd和Cu的解吸效果好于SDBS和TritonX-100,而且3种表面活性剂对各重金属的解吸率大小都为Cd>Zn>Cu>Pb.3种表面活性剂促进长柔毛委陵菜叶、柄和根的生物量增加了0.2~2.5倍,并且长柔毛委陵菜各部位的生物量大小为叶>柄>根.3种表面活性剂都增加了长柔毛委陵菜各部位对Zn、Cd吸收及其叶和柄对Pb、Cu的吸收,同时显著促进Zn、Pb、Cd和Cu从植物根部向地上部转运,从而增加了Zn、Pb、Cd和Cu在长柔毛委陵菜地上部的提取量和分布以及长柔毛委陵菜对Zn、Pb、Cd和Cu的富集能力;因此3种表面活性剂都提高了长柔毛委陵菜修复重金属污染土壤的效率.  相似文献   

17.
Studies on two lead and zinc smelters in Northern France (Metaleurop Nord and Umicore) showed that the level of metallic contamination of kitchen garden soils is higher than the agricultural soils located in the same environment. This results most particularly from cropping practices and the addition of various products. Due to the physical and chemical parameters of these soils, the behaviour and transfer of pollutants towards various plants (grass, trees, and vegetables) may be perceptibly different than what is observed on agricultural soils.For a better understanding of pollutant behaviour in kitchen garden topsoils, the Cd, Pb and Zn was fractionated using the SM&T protocol and various extracting solutions (CaCl2, acetic acid, and citric acid) to evaluate their mobility in two highly contaminated soils chosen in the area affected by the past atmospheric emissions of the two smelters. In addition, agricultural topsoil was sampled in a non-massively contaminated area and was therefore chosen as the control soil.The three soils were amended with a mixture of hydroxyapatite (HA) and diammonium phosphate (DAP). At 6 months, extracting procedures were carried out to evaluate the effects of the amendment on the mobility of Cd, Pb and Zn. This step was then supplemented by an evaluation of the impact of the amendment on the phytoavailability of pollutants, which was determined in plant uptake studies with ryegrass (Lolium perenne L.) by considering only the pollutant concentrations in their shoots. Two experiments were carried out. In the first one, unamended and amended soils and ryegrass were watered with distilled water (pH = 7). In the second one, osmosed water (pH = 5.5) was used to evaluate the effects of the acid water-phosphate amendment system on the mobility and phytoavailability of Cd, Pb and Zn. Six months after the start of the experiments, the selective extractions showed that the effectiveness of the amendment studied depended on the element, the soil and the water's pH. Reductions of metal eluted from the contaminated soils were 1.5-37.9% for Cd, and 9.1-80.9% for Pb. Application of P amendment to the combination of osmosed water was generally the most effective for immobilising Cd and Pb elution. In contrast, the mixture of HA and DAP was ineffective for reducing Zn elution. The plant-fresh biomass yield was significantly (p < 0.05) increased by the combination of P amendment and distilled water, whereas a reduction of biomass was recorded with the combined amendment and osmosed water. Addition of P amendment generally reduced Pb uptake in ryegrass shoots (1-47%), while both Cd and Zn were increased by 17.9-79% and 0.45-100%, respectively.  相似文献   

18.
This study investigates the modulation of antioxidant defence system of Typha angustifolia after 30 days exposure of 1 mM chromium (Cr), cadmium (Cd), or lead (Pb). T. angustifolia showed high tolerance to heavy metal toxicity with no visual toxic symptom when exposed to metal stress, and Cd/Pb addition also increased plant height and biomass especially in Pb treatment. Along with increased Cr, Cd, and Pb uptake in metal treatments, there was enhanced uptake of plant nutrients including Ca and Fe, and Zn in Pb treatment. A significant increase in malondialdehyde (MDA) content and superoxide dismutase (SOD) and peroxidase (POD) activities were recorded in plants subjected to Cr, Cd, or Pb stress. Furthermore, Pb stress also improved catalase (CAT), ascorbate peroxidase (APX), and glutathione peroxidase (GPX) activities; whereas Cr stress depressed APX and GPX. The results indicate that enzymatic antioxidants and Ca/Fe uptake were important for heavy metal detoxification in T. angustifolia, stimulated antioxidative enzymes, and Ca, Fe, and Zn uptake could partially explain its hyper-Pb tolerance.  相似文献   

19.
通过模拟不同地下水位的方法,对疏花水柏枝(Myricaria laxiflora(Franch.)P.Y.Zhang et Y.J.Zhang)一年生幼苗在不同条件下地上与地下部生物量及构件的变化进行测定,分析幼苗生长对地下水位变化的响应。结果显示:随着地下水位的降低,疏花水柏枝幼苗的生长特征指标均呈先增加后减少的趋势,其中地上、地下部分生物量的最高值分别为0.0438、0.0100 g,最低值分别为0.0177、0.0026 g。幼苗地上部生物量在-10 cm处理水平最高;地下部生物量在-15 cm处理水平最高。幼苗直径、根表面积、株高、主根长度、根体积、一级枝数、二级枝数等指标也分别在-10 cm或-15 cm处理水平达到最高值。疏花水柏枝幼苗主要构件的生长与地下水位的变化存在显著相关性。主成分分析结果表明,幼苗的地下部分更容易受到土壤地下水位变化的影响,幼苗性状症候群随地下水位的变化而发生移动,说明该物种幼苗在不同地下水位时的生长投资策略具有较大差异。  相似文献   

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