贵州省生态系统服务价值与社会经济空间相关性分析

基于2000年,2010年土地利用与社会经济数据,利用GeoDA模型分析了贵州省生态系统服务价值（ESV）与城镇化率、人均GDP、人口密度之间空间相关性。结果表明:2000年和2010年ESV与城镇化率、人均GDP、人口密度呈负相关;10 a间,ESV变化与城镇化率变化、人均GDP变化呈正相关,与人口密度变化呈负相关。ESV与城镇化率、人均GDP、人口密度之间高—低相关多分布中部,低—高相关多分布东南部和西北部,低—低和高—高相关分布较少且分散。ESV变化与城镇化率、人均GDP变化之间低—高相关和高—高相关分布北部和西北部,低—低相关分布中部。ESV变化与人口密度变化之间高—低相关分布中部,低—高相关和高—高相关分布北部和西北部。     

中国土地利用与生态服务价值空间动态研究——以地级及以上城市为例

为了研究土地利用对生态服务价值(ESV)的影响,基于中国地级及以上城市1990—2018年土地利用和社会经济数据,采用土地利用动态度、ESV评估模型、敏感性指数和空间自相关等方法,对研究区土地利用和ESV的时空分异特征进行了研究,分析了ESV与综合土地利用动态度、社会经济指标的空间相关性。结果表明:整体而言,除草地面积减少外,其他用地类型均有增加,各用地类型的动态度存在明显差异,综合土地利用动态度随年份有所增加; 研究期内,ESV总体上呈减少趋势,不同土地类型生态服务价值敏感性指数均<1; 研究期内生态服务价值变动与综合土地利用动态度呈负相关,各年份生态服务价值与社会经济指标综合值的双变量LISA图空间特征较为一致,低—高型主要分布于经济发展较快的中、东部地区,高—低型则主要分布于草地面积广泛、经济发展较为落后的西部地区。不同用地类型和社会经济因素对不同区域ESV影响具有一定差异,可为实现中国促进区域环境保护和经济可持续发展提供更加科学的决策服务。     

安徽省生态系统服务时空变化及权衡-协同关系

探析生态系统服务的变化特征及其权衡与协同关系,为制定生态环境保护政策和区域发展规划提供决策参考。利用1990—2018年4期土地利用数据,运用当量因子法、GIS空间分析与地理探测器模型,基于格网尺度刻画安徽省生态系统服务价值(Ecosystem Service Values, ESV)时空演变特征和权衡/协同关系,探讨了影响ESV空间分异的主要因素及其交互作用。结果表明：(1)在1990—2018年期间安徽省ESV呈不断减少趋势,从研究初期的3 647.37亿元(1990年)减少至3 567.78亿元(2018年),下降了79.59亿元。(2)空间尺度上,ESV空间分布格局变化较小,空间异质性明显,呈现明显的南高北低的空间分异特征。(3)数值关系上,4种典型生态系统服务之间呈现不同强度的协同关系。空间分布上,生态系统服务的空间权衡/协同表现出显著的分异特征,一对生态系统服务的权衡与协同关系因空间尺度不同而存在一定差异。(4)县域尺度ESV空间分异格局是多种因素综合作用的结果,其中人口密度和人为影响综合指数对区域ESV空间差异的决定力显著强于其他因素。两两驱动因子交互作用对ESV的影响力...     

生态系统服务价值与社会经济相关性研究——以重庆市大都市区为例

以重庆市大都市区为研究区,以2003年和2013年的土地利用数据为基础,探讨不同地域单元生态系统服务价值时空变化,采用熵值法对社会经济综合发展水平进行衡量,并运用空间自相关模型分析其社会经济综合发展水平和生态系统服务价值之间关系。结果表明:研究期间,生态系统服务价值增长100.98亿元,空间分布表现为东南高西北低,区域中部主城区为低值聚集区的基本形态;社会经济综合发展水平整体提高,空间分布以主城核心区为中心逐渐向外降低;社会经济综合发展水平与生态系统服务价值呈现空间负相关关系,其中高—高聚集区和高—低聚集区分布在区域中部的主城区,低—低聚集区分布在区域西部,低—高区域分布在东南部。10a间,高—高聚集区范围扩大,高—低聚集区和低—低聚集区范围缩小,低—高聚集区无明显变化。     

熵视角下延安市生态系统服务价值时空递变规律及其影响因子

退耕还林还草工程显著改变了延安市土地利用情况,进而改善了延安市的生态环境,评估这一过程的生态环境变化情况有利于后续生态保护与规划决策。基于1990—2020年土地利用、自然和社会统计数据,利用时间信息熵模型和地理探测器探究退耕还林还草工程实施前后延安市生态系统服务价值(ESV)时空递变规律及影响因子。结果表明：(1)1990—2020年延安市生态系统服务价值总体增加7.7亿元,增幅约32.42%。林地生态系统服务价值增加了11.25亿元,增幅为80.54%,是增长的主要贡献者,调节服务价值占比50%。(2)延安市生态系统服务价值整体呈现出“南高北低”的空间分布格局,有25.1%的区域ESV上升,分布在延安北部和中南部,6.4%的区域ESV降低,分布在各区县城郊地带。(3)归一化植被指数(NDVI)是ESV空间分异的主要影响因子,各因子间的交互作用共同影响了延安市的ESV空间分异。     

基于土地利用的三峡库区近30年生态系统服务价值时空变化特征

为了分析和探究三峡库区生态系统服务价值的时空变化特征,以Landsat TM/Landsat 8 OLI遥感影像为基础数据,运用RS和GIS技术提取了研究区1986年、1995年、2000年、2007年、2010年和2018年的土地利用数据,并运用土地利用动态指数模型和土地利用程度指数模型对其土地利用类型的变化趋势进行了分析。另一方面,核算了研究区相应年份的生态系统服务价值,并分析了其时空演变特征,同时对土地利用程度与ESV的相关关系进行了分析。结果表明:(1)1986-2018年,三峡库区耕地、林地和草地面积呈现减少的趋势;水域、建设用地和未利用地面积呈现增加的趋势;(2)不同土地利用类型的变化速度具有差异性,其中,建设用地和水域变化较快,耕地、林地、草地和未利用地变化较慢;(3)1986-2018年,三峡库区生态系统服务价值总量由1639.56亿元持续增长到1662.01亿元,整体增幅1.37%;(4)研究区ESV具有空间正向自相关性,其中高值区聚集明显,中低值区分区域相邻布局;(5)土地利用程度与ESV存在强烈的正相关关系。三峡库区近30年来的生态系统服务价值整体上有所提升,生态状况有所改善,但区域间差异较大,局部地区仍需特别关注,生态系统服务价值与土地利用之间存在着密切相关性。     

旅游型乡村景观格局变化及生态系统服务价值响应——以江苏省无锡市太湖国家旅游度假区为例

[目的] 探究旅游型乡村景观格局演变过程及生态系统服务价值（ESV）响应,为合理规划乡村景观资源提供科学依据。[方法] 以无锡市太湖国家旅游度假区马山半岛为例,选取1984—2020年5期遥感影像进行景观分类,计算土地利用动态度、转移矩阵、景观格局指数。基于当量因子法评估生态系统价值（ESV）,并计算各景观类型ESV敏感性指数。此外,运用SPSS对ESV与景观格局指数进行相关性和回归分析。[结果] ①1984—2020年,马山半岛景观格局变化显著,各类景观转换频繁。建设用地、灌草丛面积增加,阔叶林地、水系、裸地和其他用地缩减。景观格局趋于破碎化、复杂化,且连通性减弱。②马山半岛水系、阔叶林地ESV的比例最大,对区域ESV贡献最高。ESV呈下降趋势,累计缩减7.08×10⁵元,且各单项ESV均降低,调节服务缩减最严重。③马山半岛ESV与景观格局指数相关性显著,但各指数影响程度不同。[结论] 随着旅游业建设发展,度假区马山半岛景观格局、ESV变化显著,且二者相关性显著,通过调整关键景观格局特征可提高生态系统服务效益。     

植被覆盖变化与土壤保持演变空间异质性研究

为定量研究植被覆盖与土壤保持两者之间的关系及植被覆盖对土壤保持的影响,选取十大孔兑为研究区,利用趋势分析法、空间自相关分析、InVEST模型,重点分析十大孔兑2000—2020年植被覆盖、土壤保持时空变化及植被覆盖变化对土壤保持的作用。结果表明：(1)研究期内,十大孔兑区植被覆盖均呈增加趋势;(2)2000—2020年,土壤保持量随着植被覆盖的增加而增加,说明植被覆盖增加对于土壤侵蚀有明显的抑制作用,对土壤保持服务功能有明显的促进作用;(3)植被覆盖与土壤保持局部空间自相关,Moran’s I指数<0,但2000—2020年相关系数逐渐增大,在空间分布上,相关性分布差异明显,“高—高”和“低—低”分布在中游库布齐风沙区以及上游丘陵沟壑区有零星分布,“高—低”和“低—高”分布在上游丘陵沟壑区和下游冲积平原区,主要是上游丘陵沟壑区海拔较高,对于土壤保持能力较强,但植被覆盖度较低,下游冲积平原区主要为农田生态系统,生长季NDVI较高,但土壤抗蚀性差,土壤保持能力较弱。通过对十大孔兑区植被覆盖变化和土壤保持演变及其空间异质性和相关关系进行分析,说明植被覆盖增加在一定程度上对土壤保持有促进...     

流域生态系统服务价值、生态风险过程及其关联性——以淮河流域安徽段为例

[目的] 明确流域生态系统服务价值和生态风险的时空格局及相互关系,为保证生态系统健康可持续发展,维护区域生态系统平衡,促进人地关系协调发展提供科学依据,为淮河流域综合治理的政策制定提供科学参考。[方法] 基于淮河流域安徽段2000—2019年的土地利用数据和社会经济统计数据,利用动态当量法构建生态系统服务价值（ESV）动态评估模型,核算研究区各年份ESV,并结合空间探索性数据分析,探讨ESV与生态风险（ER）时空演化过程的异质性和关联性。[结果] ①2000—2019年研究区地类转换频繁,其中建设用地、农田转入转出最多（1 488,1 763 km²）。② ESV总量呈波动上升趋势。2000—2019年ESV总量从3.13×10¹⁰元增至3.58×10¹⁰元,生态系统服务以调节服务为主,农田和水域对ESV总量贡献率达70%以上。ESV高值区主要在六安市以及淮河支干流两侧。③ER指数整体较稳定,研究区ER均值波动幅度在0.01范围内,空间分布整体呈现出中部高、西南低的特征,ER高值区主要在城镇建设用地周围。[结论] 研究区ESV总量呈动态上升趋势,ESV与ER具有空间集聚性,并且二者存在负向空间关联特征。     

2000——2013年衡阳市土地利用格局转变对生态系统服务的影响

将生态系统服务评估利用到区域生态保护决策中的重要途径之一是生态系统服务制图.本研究对衡阳市多期遥感影像进行解译,采用当量因子法估算其生态系统服务价值(ESV)及由土地利用格局转变而引起的价值损益;并在ArcGIS 10.0软件支持下,利用空间自相关、高低聚类及重心分析等空间统计方法,对衡阳市ESV的时空变化进行制图模拟,以期为衡阳市的生态保护规划与管理提供决策辅助.研究结果表明:1)2000—2013年衡阳市的ESV略有降低,由2000年的2410亿元降至2013年的2394亿元;转移矩阵分析发现林地及耕地转为建设用地,以及林地转为耕地是引起衡阳市ESV降低的最主要原因.2)衡阳市的ESV高值区对低值区呈包围态势;2000—2013年ESV损失区主要分布于市区及其东部区域,而增值区主要分布于市区西部区域.3)衡阳市ESV的空间自相关与高低值聚集现象明显,其程度趋于增强;ESV重心向西偏北9°方向迁移了245.73 m.可考虑通过限制林地及耕地向建设用地的转变、实施"存量"或"减量"用地政策、维护和强化区域整体生态系统格局的连续性等措施来提高研究区的生态系统服务价值.     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.     

Variation in quality parameters between and within 14 Nordic tree fruit and berry species

Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.     

Potassium Fixation and Release Characteristics in Rhizosphere and Nonrhizosphere Soils for a Rapeseed–Rice Cropping Sequence

Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L^?1 nitric acid (HNO₃) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L^?1 ammonium acetate (NH₄OAc) and 1.0 mol L^?1 HNO₃ extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.     

Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater

Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells.     

Biodiversity and ecogeography of wild Lactuca spp. in some European countries

Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.     

Increase in auxiliary photoprotective photosynthetic pigments in wheat seedlings induced by Azospirillum brasilense

Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene. This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots. Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production or the positive response of the plants towards A. brasilense Cd inoculation.     

In-situ enrichment and analysis of atrazine-degrading microbial communities using atrazine-containing porous beads

We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg⁻¹ buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg⁻¹ in conditioned and control soil, respectively. The results demonstrate that BioSep^® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation.