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该文介绍了优先度排序径向基函数(PORBF)神经网络的结构与算法,并提出了将其应用于与文本无关说话人确认时的训练算法,似然度的计算方法以及识别规则。为了增强PORBF网络的泛化能力,该文用压缩矢量构造抑制样本集,提出了顺序选取、最近邻选取和最远距离选取等3种选择抑制样本集中说话人的方法,并对PORBF神经元的输出进行了等比递减加权。在相同条件下的与文本无关说话人确认实验中,传统的矢量量化方法的等差错率可达10.56%,而基于PORBF网络的确认系统使用最近邻选择方法构造抑制样本集,其等差错率可达6.83%,性能提高很多。

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合叶苔科Scapaniaceae隶属于苔纲Hepaticae叶苔目Jungermanniales,全世界约6属136个现存种,1个化石种。合叶苔科的科和属的特征明显,但物种间变化大,分类比较困难,部分属种的分类位置亦存在争议。本研究前,中国已记录合叶苔科植物有4属,66种3变种,其中9种1变种已归为同物异名,承认的种类共57种2变种。以中国产标本为基础发表的新分类单位共2属16种2变种。目前尚无专门针对中国合叶苔科的系统研究,因此,开展中国合叶苔科的分类、区系和生态研究,对深入认识中国苔类植物多样性、区系和系统具有重要的科学意义。 本研究运用植物学经典分类的基本方法和现代的分支系统分析方法,对国内、外主要苔藓植物标本馆的中国合叶苔科植物的模式标本和有关标本进行了较全面的检查和详细的形态解剖和分类学研究,并开展了野外补充调查采集,完成了对中国合叶苔科植物的分类修订,分析该科的区系成分组成和在中国的地理分布特点及其属种之间的分支系统关系。研究的主要结果如下: (1)在相关模式标本和国内外标本鉴定和研究的基础上,确认中国合叶苔科有3属52种1变种,包括:大褶叶苔属Macrodiplophyllum1种,褶叶苔属Diplophyllum5种,合叶苔属Scapania46种1变种。发现并发表新种2个,即片毛合叶苔S. macroparaphyllia T. Cao, C. Gao & J. Sun(曹同等,2004)和毛茎合叶苔S. paraphyllia T. Cao, C. Gao, J. Sun et B. R. Zuo(Zuo et al., 2007);发现中国新分布记录2种,尖瓣合叶苔S. ampliata Steph.(Zuo & Cao, 2007)和扁平合叶苔S. compacta (Roth) Dum.(首次报道,尚未发表)。完成了对中国合叶苔科植物的分类修订,对每个属、种都进行了文献考证、特征描述、图版绘制和分类讨论,并利用Mapinfo软件绘制了各种在中国的分布图。 (2)对相关模式标本标定和研究,澄清了一些分类问题和中国种的概念。如对东亚分布的若干种类进行了比较和评估,划定其分类界限,确认2种已经被归并为弯瓣合叶苔S. parvitexta Steph.新异名的种类仍然为独立的种,即细齿合叶苔S. parvidens Steph.和灰绿合叶苔S. glaucoviridis Horik.。并对东亚特有属种侧囊苔属的侧囊苔Delavayella serrata Steph.进行了模式标定,探讨了它的地理分布和系统位置,支持将其独立成侧囊苔科Delavayellaceae的观点。 (3)在标本鉴定和野外采集工作的基础上,合叶苔科各种在中国的分布范围大为增加,为开展中国合叶苔科的地理分布格局奠定了基础。对现有的地理分布资料的分析表明,西南地区(西藏,云南,四川,贵州)是中国的合叶苔属植物的分布中心和可能的起源中心,共有合叶苔40种,占该属总数(46种)的86.96%,其中,15种仅分布在西南地区,中国特产9种中,有8种在西南地区分布。此外,东北地区、华东地区及台湾省分布种类较多,分别为16种(34.78%),22种(47.83%)和17种(36.96%)种的分布。 (4)区系成分分析结果表明,合叶苔属Scapania主要由2大区系成分组成:东亚成分25种,占总数的51%,其中,中国-日本分布7种,中国-喜马拉雅分布9种,中国特产种9种。北温带成分22种,占总数的45%,其中有18种在亚洲,欧洲和北美洲均有分布。褶叶苔属Diplophyllum 5种,4种为北温带成分,1种为中国-日本分布的东亚成分。分析结果反映了中国苔藓植物区系的基本特点,即与欧美植物区系有密切联系,同时又体现了较强的东亚区系特色。 (5)对合叶苔属Scapania植物的生态和生境分析表明,47个分类群可分成3种主要类型:1)沼泽或水湿生;2)以腐木生为主,有时生于岩面薄土上的小型种类;3)潮湿岩面或林下土生的中等和大型种类。 (6)选取了39个反映系统发育关系的形态特征,以与合叶苔科相近的裂叶苔科Lophoziaceae中挺叶苔属Anastrophyllum 2种和裂叶苔属Lophozia 1种为外类群,运用外类群比较法对合叶苔科的的属种之间的演化关系进行了分支系统分析。结果表明,原归于合叶苔科的侧囊苔属Dalevayella为单独的一个分支,应为独立的侧囊苔科Dalevayellaceae。大褶叶苔属Macrodiplophyllum和褶叶苔属Diplophyllum植物相近,可归并为一个属,与合叶苔属Scapania同为合叶苔科Scapaniaceae下的属。中国合叶苔属47个分类群可分为若干组,主要与其生境,植物体,叶的结构,无性繁殖等特征有关,结果与目前采用的合叶苔科的分类系统与演化关系基本一致。

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半干旱风沙区是我国北方土地沙漠化严重的生态脆弱地区,建设和保护本区植被是生态建设和环境保护的当务之急。为了深入了解半干旱风沙区的植被的组成和演替动态,为当地的植被管理提供建议,本文以科尔沁沙地乌兰敖都地区为例,比较系统地探讨了本区植被的数量特征、筛选出90种具有代表性的植物种类,研究了各物种的62种功能特性、并对代表种进行植物功能型划分,从植物功能特性和功能型的角度分析了半干旱风沙区植被的分布动态和管理。 研究结果表明:(1)90种代表植物的38种营养阶段特性和24种繁殖阶段特性之间呈现显著相关(P<0.05)的特性对的比例要低于营养阶段和繁殖阶段内部,与营养特性显著相关(P<0.05)的特性对占总显著相关特性对的83.9%,营养特性是植物生长过程中非常重要的特性;(2)应用62种功能特性将90种代表植物划分为6类植物功能型,植物体内氮和钾含量、营养扩散、种子萌发率、叶面积和叶体积等是本区植物重要的功能特性,6类植物功能型分别以豆科植物、菊科植物、多年生C3草本植物、单子叶草本植物、叶片较小的植物和叶片较大植物为主的类群;(3)生长在各种沙丘上的群落类型的功能多样性低于生长在草甸草原和丘间低地植物群落中的功能多样性;(4)土壤有机质、全氮、全磷、地下水位和速效钾是影响植物种类、群落、植物功能特性和功能型分布的重要因素。

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通过对抚顺市温道林场20、53和69年生长白落叶松(Larix olgensis)人工林生物量和营养元素的积累与分配、养分利用效率和养分再吸收效率、养分生物循环的研究,探讨了长白落叶松生长发育不同阶段的养分生态学特征;对东北林业大学帽儿山实验林场17年生兴安落叶松(Larix gmelinii)人工林进行5年的施肥(NH4NO3,15 g•m-2•a-1),研究了施肥对人工林养分生物循环的影响。结果表明: (1)20、53和69年生单株落叶松生物量分别为33.14 kg•tree-1、311.42 kg•tree-1和408.46 kg•tree-1,随林龄的增长而增加。各器官生物量的分配格局为:树干>根>树枝>树皮>针叶。树干生物量的分配比例为50.16%~69.20%,随林龄的增长比例增大,而其他器官生物量的分配比例则逐渐减小。20、53和69年生单株落叶松净生产力分别为3.04 kg•tree-1•a-1、9.68 kg•tree-1•a-1和10.21 kg•tree-1•a-1,随林龄的增长而增大。针叶和树干的净生产力最大,分别占整株林木净生产力的40.07%~47.93%和27.32%~40.97%,并且随林龄的增长而增大。树枝、树皮和根的净生产力则表现出随林龄的增长呈抛物线状。 (2)20、53和69年生单株落叶松N、P、K、Ca、Mg等5种营养元素的总贮量分别为308.14 g•tree-1、2021.01 g•tree-1和2485.24 g•tree-1,随林龄的增长而增加。5种营养元素的贮量大小为:Ca>N>K>Mg>P。树干养分贮量的分配比例为19.74%~34.23%,随林龄的增长呈抛物线状。针叶、树枝和树皮的养分贮量占整株林木养分贮量的比例为35.16%~45.59%,建议在采伐木材时实施去皮、打枝等措施,留下针叶、树枝和树皮在林地中,让其自然分解以使营养元素重新归还利用,对于维持林地的养分平衡和长期生产力具有积极作用。 (3)20、53和69年生单株落叶松年吸收养分量分别为35.31 g•tree-1•a-1、97.83 g•tree-1•a-1和100.08 g•tree-1•a-1,随林龄的增长而增加。5种营养元素的年吸收量大小为:Ca>N>K>Mg>P。落叶松的养分利用效率随林龄的增长而增大,但生长到一定年龄阶段后,其养分利用效率逐渐趋于稳定。落叶松的最佳采伐年龄应为养分利用效率保持稳定时的年龄,此时采伐单位干材所带走的林地养分量较少。不同营养元素的利用效率不同,P的利用效率最高,Mg、K次之,N、Ca最低。不同器官的养分利用效率不同,树干的养分利用效率最高,其次是根、树枝、树皮,针叶最低。随着林龄的增长,树干和根的养分利用效率增大,而树枝和树皮的养分利用效率减小。 (4)落叶松叶片的N再吸收效率为50.76%~55.11%,随林龄的增长表现出增大的趋势;P和K再吸收效率分别为64.38%~68.85%和87.85%~90.62%,随林龄的增长表现出减小的趋势。从养分利用效率和养分再吸收效率综合判断,本研究区落叶松生长可能受土壤N、P、K供应的限制,3种营养元素的限制作用大小为:K>P>N。 (5)落叶松人工林养分的年吸收量、年存留量和年归还量分别为51.94~78.35 kg•hm-2•a-1、17.77~29.43 kg•hm-2•a-1和34.18~48.92 kg•hm-2•a-1,均随林龄的增长而减少,这与林分密度逐渐减小有关。5种营养元素的年吸收量和年存留量大小均为:Ca>N>K>Mg>P,年归还量大小为:Ca>N>Mg>K>P。落叶松人工林的养分循环速率为0.624~0.658,随林龄的增长而增大。5种营养元素的循环速率以Mg、N最快,Ca、P次之,K最慢。K的循环速率较低,可能与研究区土壤K含量较低而表现出的K再吸收效率较高有关。 (6)施肥导致落叶松叶片N再吸收效率显著降低,而凋落叶片的N浓度显著增加,从而使凋落叶片的C/N比由80.29降低到60.29。施肥林地凋落叶片C/N比的降低使其分解速率加快,有利于其养分归还土壤,从而加快了系统的养分循环速率,提高了系统的养分利用率。因此,在人工林经营中,施肥不仅能提高林地生产力,而且对于维持林地养分循环具有积极作用。

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森林生态系统是陆地最大的碳储存库,森林土壤呼吸是陆地生态系统土壤呼吸的重要组成部分,其动态变化将刘全球碳平衡产生深远的影响。精确测定土壤呼吸及其各组分的贡献,是目前全球变化研究中最基础和最迫切需要解决的问题。本文对长白山典型森林生态系统土壤碳通量及其过程机理进行了研究,结果表明:(1)阔叶红松林、红松云冷衫林、岳桦云冷杉林和岳桦林有不同的凋落节律;随海拔高度的上升,年凋落物量逐渐减少,分别为4.90、4.51、3.08和2.65thm-2;凋落物分解残留率与时间均呈指数关系,不同类型森林凋落物年分解常数的变化范围是25-47%之间。(2)阔叶红松林土壤总呼吸和断根土壤呼吸速率都存在明显的昼夜变化,为单峰型曲线,与土壤温度的昼夜变化趋势一致;不同森林类型土壤总呼吸和断根土壤呼吸的季节变化都比较明显,阔叶红松林、红松云冷杉林和岳桦云冷杉林变化趋势基本相似,都呈双峰型,岳桦林呈单峰型;土壤呼吸与土壤温度、大气温度之间都呈极显著(P<0.01)指数相关关系,且与土壤温度的相关性要好于与大气温度的相关性;长白山四种类型森林土壤和根系呼吸的Q10值变化范围是1.8-2.9,根系呼吸的Q10值均大于土壤总呼吸和断根土壤呼吸的Q10值;土壤含水量对呼吸速率影响较为复杂,与土壤呼吸之间没有明显的相关关系;根系对土壤总呼吸贡献的季节变化与根系呼吸的季节变化相似,生长季内测定的阔叶红松林、红松云冷杉林、岳桦云冷杉林和岳桦杉林根系呼吸对土壤总呼吸贡献平均值分别为43.6%、44.1%、45.5%和44.4%。(3)长白山典型森林生态系统土壤碳的年释放量有随海拔高度上升而减小的趋势,且阔价卜林大于针叶林。阔叶红松林、红松云冷杉林、岳桦云冷杉林和岳桦林土壤碳的年释放量分别为7392.43、7181.83、6507.29和6841.09kghm-2a-1;根系的年碳释放量分别为3332.93、2965.68、2708.84和3015.48kghm-2a-1。

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本文主要研究了实验室条件下NH_4~+和K~+在五种土壤中被矿物质固定的程度及固定过程中的铵、钾关系。0~30天的观测结果表明:83~100%的铵、钾固定发生在2天内,其中铵的固定速度大于钾。在含水量为最大持水量的50%时;施入14.29μMNH_4~+/g烘干土被固定25.0~83.3%,施入同量K~+被固定28.0~67.9%。在固定过程中,铵与钾主要是相互竞争的关系,即双方竞争同一固定位置。在同等条件下,NH_4~+ 的竞争能力比K~+ 强。NH_4~+ 的存在常常妨碍K~+的固定,而K~+的存在往往促进NH_4~+的固定(先施K~+时除外)。将三种2:1型自然土壤中铵、钾固定量与其原有的固定态铵、钾量进行相关分析,初步证明:施入NH_4~+、K~+的固定量与原有的固定态铵、钾量呈极显著的正相关关系,同时也得出:不同矿物对NH_4~+、K~+的“选择性”不同,蛭石对K~+的“选择性”强,而水云母对NH_4~+的“选择性”强。此外,在予备试验中,还对固定态铵的分析测定方法进行了研究与比较,并提出了一种测定固定态铵的新方法-H_2SO_4法。将H_2SO_4法与HF法同时用于12种不同土壤中原有固定态铵的测定。得出:H_2SO_4法测定值显著高于HF法。其原因可能是H_2SO_4法测出了非硅酸盐矿物所固定的铵(用“R-NH_4”表示),“R-NH_4”在 2:1 型土壤中占全N的0~9.5%。将H_2SO_4法、HF法和 KCl法同时用于观测四种土壤对施入NH_4~+ 的固定。结果表明:三种方法测得的变化趋势大致相同,但测定值高低不同: KCl 法>HF法≈H_2SO_4法。将三种方法所得结果进行比较研究后,初步证明:(1). "R-NH_4" 在土壤中也存在“固定”与“释放”作用;(2). “NH_4/K”处理所固定的铵比其它处理固定得更牢固。

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We propose a simple approach to generate a high quality 10 GHz 1.9 ps optical pulse train using a semiconductor optical amplifier and silica-based highly nonlinear fiber. An optical pulse generator based on our proposed scheme is easy to set up with commercially available optical components. A 10 GHz, 1.9 ps optical pulse train is obtained with timing jitter as low as 60 fs over the frequency range 10 Hz-1 MHz. With a wavelength tunable CW laser, a wide wavelength tunable span can be achieved over the entire C band. The proposed optical pulse generator also can operate at different repetition rates from 3 to 10 GHz.

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LUCC是全球变化研究的核心主题之一,也是社会经济可持续发展的关键问题。改革开放后四川的社会经济发展非常快,在各种因素的驱动下,土地利用/覆盖发生了深刻变化。目前四川省缺乏基于实际调查数据的、全域性的、具有连续时间序列的LUCC和驱动力分析及土地可持续利用研究成果,这对我们从全局上把握全省土地利用现状、发展变化趋势,利用土地政策参与宏观调控,实现长期可持续发展目标,建设资源节约型、环境友好型社会极为不利。本研究针对这一问题,选取全川八大土地利用类型作为研究对象,研究了全省1996年到2006年的土地利用/覆盖格局和变化情况,分析了不同尺度的驱动因素,对全省农用地和建设用地的集约利用状况、潜力进行了分析评价,并提出相应的对策措施。 1.1996年-2006年10年来整个省域的土地利用/覆盖格局变化。 (1)1996年-2006年全省的土地利用/覆盖格局 1996年,全省是一个以农用地为主的土地利用/覆盖格局,林地和牧草地属于优势覆盖类型(合占69.17%),居民点及工矿用地和交通用地合占只有3%左右。 2000年的LUCC格局较为明显的特点是耕地所占比重下降0.4个百分点,水域和未利用土地所占比重有所下降,牧草地保持不变,其余地类所占比重有所上升。 与2000年相比,2004年林草地的优势格局进一步得到强化(合占比重达到70.23%)。耕地面积占幅员面积的比重下降0.83个百分点,略有下降的有未利用土地、水域和牧草地。值得关注的是在“退耕还林还草”的大背景下,牧草地占幅员面积的比重下降0.04个百分点。 到2006年,仍为林草地为主导优势的格局,二者合占上升0.15%。在城市化快速推进的背景下,居民点及工矿用地中的城市用地和建制镇用地占比重超过15%,农村居民点占比重降至76%。交通用地中农村道路占比重降至57.8%,公路用地占比重升至37.5%。五个地貌区的土地利用/覆盖格局与全省的变化基本一致。值得关注的是盆西平原区的交通用地上升幅度和盆地丘陵区的未利用土地的开发利用力度明显大于其它地貌区。 (2)1996-2006年10年间土地利用/覆盖格局的变化 1996-2000年4年间,耕地、水域和未利用地三个地类下降,年均减少0.75、0.19和0.32个百分点。其中耕地年均减少49229.0公顷,约一半流向林地,13.77%流向园地,约20%流向建设用地。另外5个地类面积增长,增长绝对量最大的是林地,年均增长40063.7公顷,交通用地增幅最大,4年年均增长达1.95%。 2001-2004年是西部大开发逐步推进、“退耕还林还草”项目全面展开和土地整理深入实施的关键期,LUCC更为深刻。耕地、未利用地、水域和牧草地四个地类面积下降,其余地类按增长幅度依次是园地、交通用地、居民点及工矿用地和林地。耕地加速下降,年均降幅达到1.59%,其减少去向主要是林地(占66.75%)和园地(占19.84%),其增加来源主要是未利用地、园地和水域。交通用地的增幅最大,为3.96%,其增加主要来源于耕地、未利用土地和林地,分别占49.96%、16.63%和13.09%。居民点及工矿用地增长幅度为3.12%。 从1996年到2006年的10年间,耕地、未利用地、水域和牧草地下降幅度分别为10.36%、3.61%、1.34%和0.26%。园地增幅达23.61%。绝对面积增长最大的则是林地,达630733.3公顷。交通用地和居民点及工矿用地增幅也较大,分别为15.00%和9.31%。 10年间年均总变化量为310326.6公顷,2000年-2004年之间变化最大(为356865.8公顷),高于平均变化量,而1996-2000年间和2004-2006年间都小于平均变化量。 (3)10年间不同地貌区的LUCC变化 盆西平原区的特点是园地大幅上升达77%,居民点及工矿用地和交通用地也大幅上升,耕地、未利用地下降幅度大,该区耕地、水域、未利用地的减少强度和园地、居民点及工矿用地、交通用地的上升强度均居五区第一;盆地丘陵区的特点是牧草地下降幅度大,为-36.89%,交通用地、园地和林地上升幅度较大,该区耕地减少、未利用地减少、林地增加、居民点及工矿用地和交通用地增加的变化强度均居五区相应地类增减的第二位;盆周山地区的特点是耕地减少较多,交通用地和园地增长较大,该区林地变化强度居各区第一位,牧草地和水域变化强度居各区第二位,耕地、居民点及工矿用地和未利用地居各区第三位;川西南山地区的特点是园地、耕地、交通用地和居民点及工矿用地变化幅度大,另外四个地类变化较小。该区减少的牧草地占全省牧草地减少的97.91%,变化强度居各个地貌区的第一位,园地相对变化强度居五区的第二位;川西北高山高原区的特点是耕地大幅下降、园地大幅上升,交通用地升幅也较大,其余地类变化不大。值得注意的是,该区牧草地和水域面积增加,与全省该地类的变化相反。其余地类的相对变化强度均是五个地貌区中最小的。 用变化强度分值考量变化强度,盆西平原区的变化强度最大,盆地丘陵区和盆周山地区的变化强度相当,川西北高山高原区的变化强度则要小得多。 (4)1996年及2006年全省土地利用/覆盖格局的景观生态学分析 全省是以自然景观占优势(占约70%)、农业景观为补充、建设用地景观居于从属地位的土地利用景观格局。景观多样性和均匀度不高。到2006年,全省总的景观格局并无大的改变。总体情况是随着时间的推移和人类活动的加强,区内景观优势度上升、多样性和均匀度变小。但斑块数减少,斑块面积和斑块孔隙度有所增大。斑块的形状指数和分维数均有所下降,表明受人为干扰有加剧的趋势。反映景观格局结构的破碎度指数有轻微下降。景观指数的变化表明全省土地利用有缓慢集中、规模聚集的趋势。 (5)三大生态建设工程对土地利用/覆盖变化的影响 1996-2006年间LUCC与三大生态建设工程实施的耦合分析,发现退耕工程对耕地、林地、牧草地等地类覆盖变化的影响最大,天保工程次之,长防工程最小。 2.四川省LUCC驱动力分析 (1)总体分析: 从整体上分析,人为因素对区域整体LUCC的影响从1996年的63.32%增加到2006年的66.99%,变得日益强烈。同时人为因素影响强度表现出明显的区域差异,地势平缓、经济区位条件好的区域其人为影响强度明显较高。 政策体制转变下的经济高速增长、快速的城市化、工业化过程和生态建设是四川省LUCC宏观尺度的驱动因素。区域的LUCC主要受到了由内向外(从城市到乡村)和由外向内(从山顶向平地)两种作用力的共同推动。局部尺度上,如距离交通线、水利线、中心城市的远近,地形凸起、大型独立项目落址、重污染项目的阻隔等,甚至一些乡规民俗等因素也会成为LUCC的驱动影响因素。在较小的尺度上,人类个体行为选择对LUCC的影响也是存在的。   根据驱动因子的特性作者将其划分为驱变、阻变、良性、惰性因子等类型。 (2)分地貌区的驱动因子分析 各地貌区都存在城市化、工业化、生态工程实施、自然灾害等驱动因子,但主次不一。对于盆西平原和盆地丘陵区,城市化、工业化是前两位的因子,而对另外三个地貌区,生态工程实施和产业结构调整则成为第第一、二位的驱动因子。 (3)分地类的驱动因子分析(以坡耕地为例) 分坡度的耕地变化分析发现,耕地减少主要集中在2°以下的平地、15°-25°和25°以上三个坡度级,是其它坡度级耕地减幅的三倍左右。这表明耕地减少受城市化进程和“退耕还林还草”工程驱动影响尤为巨大。 3.土地利用格局优化、集约利用评价和可持续利用及对策研究 (1)土地利用格局优化的战略选择及调整预测 土地利用格局调整的战略是农业生产用地、建设用地和生态及其他用地占幅员的比重分别稳定在13%、7%和80%左右,重点是三大类别内部二级和三级地类的合理调整。 (2)全省土地集约利用评价 全省农用地利用集约度为0.46,总体上集约度不高,处于较适度利用阶段。建设用地利用集约度为0.38,处于较适度利用阶段。集约利用提升空间较大。 农用地的潜力主要在于加强土地保育、完善利用制度、提高单产。城市建设用地的包括存量潜力、强度潜力、结构潜力,空间很大。农村居民点整理潜力可以逐步挖掘。 (3)新增建设用地集约利用的统筹安排 据测算,到2020年,四川省城市建设用地需求量在463850-492360hm2之间,城镇各业新增建设用地规模为361276.79hm2,占用耕地200565.94 hm2。2004-2020年间四川省农村居民点整理潜力33.86万hm2。农村居民点建设用地需求量为70.57万公顷。 (4)土地集约利用措施与坡耕地可持续利用战略 提出了土地集约利用的措施。在对坡耕地生态系统结构与功能分析的基础上,提出坡耕地可持续利用战略与生态恢复战略,并从技术和政策层面提出了坡耕地合理利用和生态退耕的措施和建议。 LUCC is one of the key questions of global change and sustainable development of society. After the opening and reform of China, the society and economy of Sichuan Province developed very fast ,the land-use/cover changed very strong droved by many factors .But nowadays we have no constant spatial-temporal study and driving force analysis about the whole province based on investigation. And it is lack of land sustainable utilization study based on correlative study. So we choose all the land resource in Sichuan, combine RS and GIS and field investigation, and take statistic-mathematic means and system analysis, to study the LUCC patterns and different scale driving force of different physiognomy regions, land cover types and periods; to analyze the current situation and potential of land resource intensive utilization, and gave out corresponding measurements. We found that forest and grassland are the dominant cover types of Sichuan provincial land –use/cover pattern, and becoming more and more stronger from 1996 to 2006,the natural landscape is the metric and occupy 70%,the diversity and evenness index are not high; the totally change quantity from 2000 to 2004 is the biggest; cultivated land especially steep cultivated land ,garden plot, forestry land ,settlement and industry land and traffic land changed relative stronger; among five physiognomy regions ,the changing intensity of PEN XI PING YUAN QU is the biggest, CHUAN XI BEI GAO SHAN GAO QU is smallest; under the background of policy system changing, the fast developing of economy, fast urbanization and industrialization and ecology construction are the macro-scale driving force of Sichuan provincial LUCC; to compare the impacts of “TUI GENG GONG CHENG” on LUCC especially to cultivated land ,forestry land and grassland is strongest, “TIAN BAO GONG CHENG ” is stronger,“ HANG FANG GONG CHENG” is smallest; the intensive utilization level of farmland and construction land of whole province is relative moderation, there is huge potential to excavate and fulfill the increasing demand of construction land;we must take synthetic measurements to accelerate the sustainable utilization of land resource, including administrative, economical ,technological and ecological policies.

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本研究针对川西北高山草甸缺乏科学管理,过度放牧导致草场退化,并由此引发的一系列生态环境问题,选取红原县瓦切乡1996 年草地承包后形成的四个放牧强度草场,即不放牧、轻度(1.2 头牦牛hm-1)、中度(2.0 头牦牛hm-1)和重度放牧(2.9 头牦牛hm-1),作为研究对象,研究了不同放牧强度对草地植物-土壤系统中碳、氮这两个最基本物质的分布格局和循环过程的影响,并探讨了放牧干扰下高山草甸生态系统的管理。 1.放牧对草地植物群落物种组成,尤其是优势种,产生了明显的影响。不放牧、轻度、中度和重度放牧草地群落物种数分别为22,23,26,20 种,群落盖度分别是不放牧96.2%>中度93.6%>轻度89.7%>重度73.6%。随放牧强度的增加, 原植物群落中的优势种垂穗鹅冠草( Roegneria nutans )、发草(Deschampsia caespitosa)和垂穗披碱草(Elymus nutans)等禾草逐渐被莎草科的川嵩草(Kobresia setchwanensis)和高山嵩草(Kobresia pygmaea)所取代成为优势种。同时,随放牧强度的增加,高原毛茛(Ranunculus brotherusii)、狼毒(Stellera chamaejasme)、鹅绒委陵菜(Potentilla anserina)和车前(Plantagodepressa)等杂类草的数量也随之增加。 2.生长季6~9 月份,草地植物地上和地下生物量(0~30cm)都是从6 月份开始增长,8 月份达到最高值,9 月份开始下降。每个月份,通常地上生物量以不放牧为最高,重度放牧总是显著小于不放牧;地下生物量随放牧强度的增加表现为增加的趋势,通常重度和中度放牧显著高于不放牧和轻度放牧草地。不放牧、轻度、中度和重度放牧草地6~9 月份4 个月的植物总生物量平均值分别是1543、1622、2295 和2449 g m-2,但随放牧强度的增加越来越来多的生物量被分配到了地下部分,地下生物量占总生物量比例的大小顺序分别是重度88%>中度82%>轻度76%>不放牧69%。生物量这种变化主要是由于放牧使得群落优势种发生改变而引起的,其分配比例的变化体现了草地植物对放牧干扰的适应策略。 3.植物碳氮贮量的季节变化类似与生物量的变化。每个月份,不同放牧强度间植物地上碳氮的贮量有所不同,一般重度放牧会显著减少植物地上碳氮贮量。植物根系(0~30cm)碳氮贮量随放牧强度的增加表现为增加的趋势,通常重度和中度放牧显著高于不放牧和轻度放牧草地。不放牧、轻度、中度和重度放牧草地6~9 月份4 个月的植物总碳平均值分别是547、586、847 和909 g m-2,根系碳贮量占植物总碳的比例大小顺序分别是重度88%>中度82%>轻度76%>不放牧69%;放牧、轻度、中度和重度放牧草地6~9 月份4 个月的植物总氮平均值分别是17、17、23 和26 g m-2,根系氮贮量占植物总氮的比例大小顺序分别是重度79%>轻度71%>中度70%>不放牧65%。 4. 土壤有机碳贮量(0~30cm)的季节变化表现为7 月份略有下降,8 月开始增加,9 月份达到的最大值。土壤氮贮量的季节变化表现为随季节的推移逐渐增加的趋势。增加的放牧强度不同程度的增加土壤有机碳氮的贮量。不放牧、轻度、中度和重度放牧6~9 月份4 个月的土壤有机碳贮量的平均值分别是9.72、10.36、10.62 和11.74 kg m-2,土壤氮贮量分别为1.45、1.56、1.66 和1.83 kg m-2。土壤中有机碳(氮)的贮量都占到了植物-土壤系统有机碳(氮)的90%以上,但不同放牧强度之间的差异不明显。 5. 土壤氮的总硝化和反硝化,温室气体N2O 和CO2 的释放率的季节变化表现为从6 月份开始增加,7 月份达到最大值,8 月份开始下降,9 月份降为最小值。增加的放牧强度趋向于增加土壤氮的总硝化和反硝化作用,温室气体N2O和CO2 的释放率,通常情况下,中度放牧和重度放牧显著地加强了这些过程。 6.垂穗鹅冠草(Roegneria nutans)和川嵩草(Kobresia setchwanensis)凋落物在不同放牧强度下经过1 年的分解,两种凋落物的失重率及其碳氮的损失率3都随放牧增加表现为增加的趋势。在同一放牧强度下,川嵩草凋落物的失重率和碳氮的损失率都高于垂穗鹅冠草凋落物。 7. 尽管重度放牧显著增加了土壤碳氮的贮量,但同时也显著降低了植被群落盖度,降低了植物地上生物量,因此,久而久之会减少植物向土壤中的碳氮归还率;与不放牧和轻度放牧相比,重度放牧又显著增加了土壤CO2 和NO2 的排放量,这是草地生态系统碳氮损失的重要途径。由此可见,对于这些地处青藏高原的非常脆弱的高山草甸生态系统,长期重度放牧不仅导致植物生产力降低,而且将导致草地生态系统退化,甚至造成土壤中碳氮含量减少。 Long-term overgrazing has resulted in considerable deterioration in alpine meadowof the northwest Sichan Province. In order to explore management strategies for thesustainability of these alpine meadows, we selected four grasslands with differentgrazing intensity (no grazing-NG: 0, light grazing-LG: 1.2, moderate grazing-MG: 2.0,and heavy grazing-HG: 2.9 yaks ha-1) to evaluate carbon, nitrogen pools and cyclingprocesses within the plant-soil system in Waqie Village, Hongyuan County, Sichuan Province. 1. Grazing obviously changed the plant species composition, especially ondominant plant species. Total number of species is 22, 23, 26, and 20 for NG, LG, MGand HG, respectively. Vegetation coverage under different grazing intensity ranked inthe order of 96.2% for HG>93.6% for MG>89.7% for LG>73.6% for NG. Thedominator of HG community shifted from grasses-Roegneria nutans andDeschampsia caespitosa dominated in the NG and LG sites into sedges-Kobresiapygmaea and K. setchwanensis. At the same time, with the increase of grazingintensity, the numbers of forbs, such as Ranunculus brotherusii, Stellera chamaejasme,Potentilla anserine and Plantago depressa, increased with grazing intensity. 2. Over the growing season, aboveground and belowground biomass showed a 5single peak pattern with the highest biomass in August. For each month, abovegroundbiomass usually was the highest in the NG site and lowest in the HG site.Belowground biomass showed a trend of increase as grazing intensity increased and itwas significantly higher in the HG and MG site than in the NG and LG sites. Totalplant biomass averaged over the growing season is 1543, 1622, 2295 and 2449 g m-2for NG, LG, MG and HG, respectively. The proportion of biomass to total plantbiomass for NG, LG, MG and HG is 88%, 82%, 76% and 69%, respectively. Higherallocation ratio for is an adaptive response of plant to grazing. 3. Carbon and nitrogen storage in plant components followed the similar seasonalpatterns as their biomass under different grazing intensities. Generally, heavy grazingsignificantly decreases aboveground biomass carbon and nitrogen compared to nograzing. Carbon and nitrogen storage in root tended to increase as grazing increasedand they are significantly higher in the HG and MG sites compared to the LG and NGsite. Total Carbon storage in plant system averaged over the growing season is 547,586, 847 and 909 g m-2 for NG, LG, MG and HG, respectively, while 17, 17, 23 and 26g m-2 for nitrogen. The proportion of carbon storage in root to total plant carbon forNG, LG, MG and HG is 88%, 82%, 76%, 69%, respectively, while 65%, 71%, 70%and 79% for nitrogen. 4. Carbon storage in soil (0-30cm) decreased slightly in July, then increased inAugust and peaked in September. Nitrogen storage in soil tended to increase withseason and grazing intensity. Total Carbon storage in soil averaged over the growingseason is 9.72, 10.36, 10.62 and11.74 kg m-2 for NG, LG, MG and HG, respectively,while 1.45, 1.56, 1.66 and 1.83 for nitrogen. The proportion of carbon (nitrogen)storage in soil to plant-soil system carbon (nitrogen) storage for NG, LG, MG and HGis more than 90%, which is not markedly different among different grazing intensities. 5. Gross nitrification, denitrification, CO2 and N2O flux rates in soil increasedfrom June to July and then declined until September, all of which tended to increasewith the increase of grazing intensity. Generally, heavy and moderate grazing intensitysignificantly enhanced these process compared to no and light grazing intensity. 6. After decomposing in situ for a year, relative weight, carbon and nitrogen loss in the litter of Roegneria nutans and Kobresia setchwanensis tended to increase asgrazing intensity increased. Under the same grazing intensity, relative weight, carbonand nitrogen loss in the litter of Kobresia setchwanensis were higher than these in thelitter of Roegneria nutans. 7. Although heavy grazing intensity resulted in higher levels of carbon andnitrogen in plant and soil, it decreased vegetation coverage and aboveground biomass,which are undesirable for livestock production and sustainable grassland development.What is more, heavy grazing could also introduce potential carbon and nitrogen lossvia increasing CO2 and N2O emission into the atmosphere. Grazing at moderateintensity resulted in a plant community dominated by forage grasses with highaboveground biomass productivity and N content. The alpine meadow ecosystems inTibetan Plateau are very fragile and evolve under increasing grazing intensity by largeherbivores; therefore, deterioration of the plant-soil system, and possible declines insoil C and N, are potential without proper management in the future.

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黄龙世界自然遗产地岷江冷杉林(Abies faxoniana)生境类型多样,群落结构复杂,群落植物种类组成多样性丰富。揭示不同生境的生物多样性及其差异是认识生物多样性格局、形成及维持机制的前提和进行多样性保育的基础。本文采用样方法对黄龙钙化滩生境、阴坡非钙化生境及半阳坡非钙化生境的岷江冷杉原始林植物群落结构及植物多样性进行了研究。结果表明: 黄龙岷江冷杉林具有明显的复层异龄结构,垂直结构明显,乔木、灌木、草本、苔藓层次分明。共发现高等植物386 种,其中维管植物46 科103 属163 种,苔藓植38 科83 属物223 种。各层片结构及物种组成如下: (1)钙化滩生境、阴坡非钙化生境、半阳坡非钙化生境分别发现乔木18 种、13种、8 种。乔木层均可分为两个亚层,第一亚层优势种均为岷江冷杉,第二亚层主要为岷江冷杉异龄树或其它大高位芽物种。钙化滩生境第一亚层除优势种岷江冷杉外混生有巴山冷杉(Abies fargesii)、粗枝云杉(Picea asperata)以及阔叶树种白桦(Betula platyphylla)等,第二亚层主要为岷江冷杉异龄树;阴坡非钙化生境第一亚层除优势种岷江冷杉外间有巴山冷杉和白桦,第二亚层物种主要为川滇长尾槭(Acer caudatum var. prattii);半阳坡非钙化生境第一亚层除优势种岷江冷杉外混生有巴山冷杉,第二亚层主要为岷江冷杉异龄树。依乔木层优势种的差异,钙化滩生境及半阳坡非钙化生境为岷江冷杉纯林,阴坡非钙化生境为岷江冷杉-川滇长尾槭混交林。不同生境乔木层郁闭度、乔木密度、树高结构、直径结构均存在差异。 (2)钙化滩生境发现灌木41 种,平均盖度为18.49±1.72(%),平均高度为52.12±4.45(cm),优势种为直穗小檗(Berberis dasystachya);阴坡非钙化生境发现灌木30 种,平均盖度为29.33±2.56 (%),平均高度为119.55±8.01 (cm),优势种为箭竹 (Fargesia spathacea) 、唐古特忍冬(Lonicera tangutica) 和袋花忍冬(Lonicera saccata);半阳坡非钙化生境发现灌木29 种,平均盖度为31.35±1.93 (%),平均高度为107.55±4.24 (cm),优势种为箭竹(Fargesia spathacea)。不同生境灌木层结构和物种组成多样性差异显著,钙化滩生境的灌木盖度、高度总体上较非钙化的坡地生境低, 钙化滩生境灌木以小型叶的落叶灌木为主,沟两侧非钙化的坡地生境上则发育了丰富箭竹。 (3)钙化滩生境发现草本46 种,平均盖度为7.18±0.79 (%),平均高度为5.04±0.26(cm),以山酢浆草(Oxalis griffithii)为优势种;阴坡非钙化生境发现草本物种71 种,平均盖度达29.04±2.31(%),平均高度为9.08±0.52(cm),以钝叶楼梯草(Elatostema obtusum)、山酢浆草为优势种;半阳坡非钙化生境草本物种50 种,平均盖度为以8.79±0.82(%),平均高度为7.67±0.43 (cm),以扇叶铁线蕨(Adiantum flabellulatum)、双花堇菜(Viola biflora)、华中蛾眉蕨(Lunathyrium shennongense)、山酢浆草为优势种。阴坡非钙化生境草本层片发育良好,多样性最为丰富,盖度和物种丰富度均显著高于钙化滩生境和半阳坡非钙化生境。 (4)钙化滩生境发现苔藓物种140 种,平均盖度达84.25±1.30 (%),以仰叶星塔藓(Hylocomiastrum umbratum) 等大型藓类为优势种;阴坡非钙化生境发现苔藓物种115 种,平均盖度为79.29±1.64 (%),以刺叶提灯藓(Mnium spinosum)、大羽藓(Thuidium cymbifolium)、毛尖燕尾藓(Bryhnia trichomitra)等个体较小的物种为优势种;半阳坡非钙化生境发现苔藓物种91 种,平均盖度为60.64±1.93 (%),也以刺叶提灯藓为优势种。 (5)钙化滩生境、阴坡非钙化生境、半阳坡非钙化生境的物种数分别为234 种、221 种、175 种。乔木层的Shannon-Wiener 指数分别为0.75 ±0.12、1.87±0.12、1.78±0.07(灌木层,0.44±0.08、1.71± 0.15、2.49±0.06;草本层,0.33±0.13、1.31±0.15 、2.15±0.08; 苔藓层1.30±0.11、2.08±0.04、1.73±0.11,);Pielou 均匀度指数分别为0.45±0.05、0.29±0.06、0.28±0.08(灌木层,0.75±0.03、0.68±0.05、0.52±0.06;草本层,0.68±0.02、0.77±0.02、0.74±0.02;苔藓层,0.40±0.03、0.63±0.02、0.52±0.03);Simpson's 优势度指数分别为0.63±0.06、0.78±0.04、0.83±0.07(灌木层,0.21±0.03、0.28±0.05、0.45±0.06;草本层,0.25±0.02、0.12±0.01、0.17±0.01;苔藓层,0.45±0.04、0.18±0.01、0.31±0.04)。三种生境间乔木层、草本层的Sorenson 群落相似性系数较低, 灌木层、苔藓层的的Sorenson 群落相似性系数较高。 综上所述,黄龙岷江冷杉林的群落结构、植物多样性在三种生境间存在差异性,这将意味着我们在进行黄龙世界自然遗产地的森林经营管理时要较多地关注岷江冷山林群落在不同生境中的差异性。 There were multiplex habitat types, complicated community structure and abundant species composition in the Huanglong World Natural Heritage Site. Uncovering the differences of biodiversity among different habitats was a precondition to understand the distribution, formation and sustaining mechanism of the biodiversity, and the foundation of biodiversity conservation. In the present study, using plenty of quadrants, we investigated the community structure and the biodiversity of the primitive Abies faxoniana forest in different habitats (travertine bottomland, semi-sunny-slope non-calcified habitat and shady-slope non-calcified habitat) in the Huanglong World Natural Heritage Site. The main results are as follows: All the primitive Abies faxoniana forests in the three habitats were uneven-aged with obvious vertical structure including tree layer, shrub layer, herb layer and bryophyte layer. A total of 386 higher plants including 163 vascular plant species (103 generic, 46 families) and 223 bryophyte species (83 generic, 38 families) were investigated. The structure and species composition of each layer are as follows: (1) There were 18, 13 and 8 tree species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. The tree layers in all habitats can be divided into two clear sub-layers. The upper tree layers were dominated by Abies faxoniana, and the lower tree layers were dominated by uneven-aged Abies faxoniana or other phanerophytes species. There were Abies fargesii , Picea asperata and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in travertine bottomland, and the lower tree layers were dominated by uneven-aged Abies faxoniana; There were Abies fargesii and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in shady-slope non-calcified habitat, and the lower tree layers were dominated by Acer caudatum var. prattii; There was Abies fargesii besides the dominated species (Abies faxoniana) in the upper tree layer semi-sunny-slope non-calcified habitat, and the lower tree layers were dominated by uneven-aged Abies faxoniana. According to composition percentage of dominate species in tree layer, both the forest in travertine bottomland and in semi-sunny-slope non-calcified habitat could be ranked as pure forest, and the forest in shady-slope non-calcified habitat could be ranked as mingled forest. There were significant differences in crown density, plant density, height structure and diameter structure among the three habitats. (2) A total of 41 shrub species (average coverage 18.49±1.72%; average height 52.12±4.45 ㎝)were found in travertine bottomland, and the dominate species was Berberis dasystachya; A total of 30 shrub species (average coverage 29.33±2.56 %;average height 119.55±8.01 ㎝)were found in shady-slope non-calcified habitat, and the dominate species was Fargesia spathacea, Lonicera tangutica and Lonicera saccata. A total of 29 shrub species (average coverage 31.35±1.93%; average height 107.55±4.24 ㎝) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Fargesia spathacea. There were significant differences in structure and species diversity of the shrub layers among the three habitats. The coverage and height of shrub had lower value in travertine bottomland than in two non-calcified habitats. Moreover, travertine bottomland was dominated by deciduous shrub species with microphyll and non-calcified habitats developed abundant Fargesia spathacea species. (3) A total of 46 herb species (average coverage 7.18±0.79%;average height 5.04±0.26 ㎝)were found in travertine bottomland, and the dominate species was Oxalis griffithii; A total of 71 herb species (average coverage 29.04±2.31%;average height 9.08±0.52 ㎝)were found in shady-slope non-calcified habitat, and the dominate species was Elatostema obtusum and Oxalis griffithii. A total of 50 herb species (average coverage 8.79±0.82%;average height 7.67±0.43 ㎝) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Adiantum flabellulatum, Viola biflora, Lunathyrium shennongense and Oxalis griffithii. Herb layers developed well in shady-slope non-calcified habitat and had the higher species richness and coverage than travertine bottomland and semi-sunny-slope non-calcified habitat. (4) A total of 140 bryophyte species (average coverage 84.25±1.30%)were found in travertine bottomland, and the dominate species was big bryophyte species such as Hylocomiastrum umbratum and so on; A total of 115 bryophyte species (average coverage 79.29±1.64%)were found in shady-slope non-calcified habitat, and the dominate species was small bryophyte species such as Mnium spinosum, Thuidium cymbifolium, Bryhnia trichomitra and so on. A total of 91 bryophyte species (average coverage 60.64±1.93%) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Mnium spinosum. (5) There were 234, 221 and 175 plant species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. Shannon-Wiener index of the tree layer was 0.75 ±0.12, 1.87±0.12 and 1.78±0.07 (the shrub layer, 0.44±0.08, 1.71± 0.15 and 2.49±0.06; the herb layer, 0.33±0.13, 1.31±0.15 and 2.15±0.08; the bryophyte layer, 1.30±0.11, 2.08±0.04 and 1.73±0.11.) for the three habitats, respectively; Pielou index of the tree layer was 0.45±0.05, 0.29±0.06 and 0.28±0.08 (the shrub layer, 0.75±0.03, 0.68±0.05 and 0.52±0.06; the herb layer, 0.68±0.02, 0.77±0.02 and 0.74±0.02; the bryophyte layer, 0.40±0.03, 0.63±0.02 and 0.52±0.03.) for the three habitats, respectively. Simpson's index of the tree layer was 0.63±0.06, 0.78±0.04 and 0.83±0.07 (the shrub layer, 0.21±0.03、0.28±0.05、0.45±0.06; the herb layer, 0.25±0.02, 0.12±0.01 and 0.17±0.01; the bryophyte layer, 0.45±0.04, 0.18±0.01 and 0.31±0.04.) for the three habitats, respectively. There were low Sorenson index both in the tree layer and in the herb layer among the three habitats, whereas, high Sorenson index occurred both in the shrub layer and in the bryophyte layer. To sum up, there were differences both in community structure and plant diversity among the three different habitats, which means that we should pay more attention to habitats heterogeneities of the primitive Abies faxoniana forest when we take action to manage the forest in the Huanglong World Natural Heritage Site.

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一体化反应器由于投资少、占地小、管理运行方便等优点而备受青睐。但现有的一体化反应器大都适用于处理中低浓度废水,耐受负荷普遍偏低。本课题研制出新型高效的厌氧好氧一体化生物反应器,旨在通过反应器结构优化、高效微生物载体研制、配合高效微生物菌剂技术处理中高浓度有机废水,实现高效和低耗,降低设备造价,提高反应器运行稳定性。 首先开展了菌剂对废水的适配试验。采用15种不同的微生物菌剂,以葡萄糖配水、中药提取废水、啤酒废水、氨氮配水为基质,分别测定了微生物菌剂的耗氧速率和厌氧比产甲烷速率,以其为指标比较了各菌剂对废水的适配性。根据结果选择活性高的14#、8#、10#菌剂,在试验室进行了菌剂对废水的连续处理试验,取得良好的处理效果,为菌剂在厌氧好氧一体化生物反应器的小试、中试中的应用奠定了基础。 经小试研究后,又对厌氧好氧一体化生物反应器进行了处理发酵废水的中试研究。试验结果表明,反应器启动快,系统有机负荷2.72 kgCODm-3d-1时整个反应器去除率保持在84.5%~93.19%,在30多天内一次启动成功。冲击负荷试验中,系统总有机负荷最高可达到8.88 kgCODm-3d-1,系统去除率稳定在88.10%~96.88%,说明反应器处理效率高,抗冲击能力强。稳定运行期间,COD去除率可达90%以上,各项指标都能达到国家排放标准。 此外,对反应器配套系统高效菌剂、高分子复合颗粒载体进行了研究。结果显示,菌剂与反应器适配良好,各功能区形成了丰富、高活性的微生物,厌氧区颗粒污泥TS高达83.9 gL-1,VS/TS为56.9%~57.4%,比产甲烷活性为280~350 mLCH4 gvss-1d-1;好氧区固定化微生物TS高达1.921 gL-1,VS/TS为94.02~94.30%。对载体性能的研究表明,此高分子复合颗粒载体密度适中,易于流化,不易流失;粗糙多空,易于挂膜;且无生物毒害作用,稳定安全,是一种优良的生物载体。反应器各功能区对废水的降解过程分析,说明了反应器、菌剂、载体适配良好,在其协同作用下,实现了污染物的高效降解。 The integrated reactors were popular because of their characteristics such as little investment, small occupation of land, convenient of manage and running etc. But the present integrated reactors were mostly applied for treating wastewater of low concentration, the load tolerance was generally on the low side. A new type integrated anaerobic-aerobic bio-reactor was developed, which was conducted to treating organic wastewater of middle or high concentration by optimization of reactor structure, development of efficient microbe carrier and adaptation of high active microbial blends, to achieve high efficiency and low consume, reduce equipment cost, enhance running stabilization of reactor. The adaptability test of microbial blends on different wastewater was carried on firstly. Oxygen consumption rate and anaerobic specific activity of methane producing of 15 different microbial blends were measured separately taking glucose artificial wastewater, Chinese herb extracting wastewater, brewery wastewater and ammonia nitrogen artificial wastewater as substrate, by which the adaptabilities of different microbial blends to wastewater were compared. According to the results high active microbial blends 14#, 8# and 10# were selected and used in the continuous treatment of wastewater in the laboratory and had obtained good effect, which had laid a foundation for application microbial blends to small scale test and pilot test of integrated anaerobic-aerobic bio-reactor. After the small scale test, the pilot test of the integrated anaerobic-aerobic bio-reactor treating fermentation wastewater was carried on. The test results showed fast initiation of the reactor. When system organic load reached 2.72 kgCODm-3d-1the COD removal rate of the reactor was stable between 84.5%~93.19% and it initiated successfully in more than 30 days at a time. In the load shock test the maximum organic load of system could reach to 8.88 kgCODm-3d-1 and the COD removal rate could be stable between 88.10%~96.88% which indicated that the reactor was efficient for treating wastewater and had strong resistance to shock load. At stable running period the COD removal rate of the reactor was over 90% and each index of wastewater could reach to the national discharge standards. In addition, the high active microbial blends and the macromolecule compound granule carrier, the matching system of the reactor was studied. It showed that the microbial blends adapted well to the reactor and abundant and high active microbes were formed in each functional field. The TS of granule sludge in anaerobic field was as high as 83.9 gL-1, the VS/TS was 56.9%~57.4%, the specific activity of methane producing was 280~350 mLCH4 gvss-1d-1. And the TS of immobilized biological granule was as high as 1.921 gL-1, the VS/TS was 94.02%~94.30%. Study on the carrier showed that the self-made macromolecular compound granule carrier was moderate of density, easy of fluidization, unease of running off, rough and porous, easy of films fixation, no bio-toxic, stable and safe, was a kind of superior carrier. Analysis of degradation process in each functional field confirmed the reactor, microbial blends and carriers were in good adaptation and wastewater was decontaminated by their cooperation.

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本文介绍了从厌氧间歇膨胀光合反应器内的活性污泥中分离并鉴定的泥生绿菌(Chlorobium limicola Nadson)S1,它属严格厌氧光能自养型细菌,在有硫化物和少量碳酸氢盐存在下,有广泛利用有机物的能力,它的最适生长温度为28-30℃,最适生长PH为6.5-7.0,且含有氢化酶。因此,它能与甲烷发酵菌共存而共同作用,达到废水净化之目的。通过光照(2#反应器)和黑暗(1#反应器)对比实验,表明了在光照条件下即有泥生绿菌S1存在下,反应系统能更好地降低CODcr、BOD5 和提高CH4 含量,在四个负荷段的运行中,2#反应器在后三个负荷段的甲烷含量能稳定在91.6%而1#反应器为87%,2#反应器的二氧化碳含量为4.5%而1#反应器为8.8%,于28.35g/l.d的负荷下,2#反应器CODcr去除率达83.4%,BOD去除率达74.53%,分别较1#反应器高10.8%,6.4%。COD去除率提高了14%,BOD去除率提高了9.3%。本试验的试验条件为:白天自然光照,晚上电源光照,光照强度为1000-2500lux,通过连续动态运转,并以恒定的流速将废液注入反应器中,进水PH控制在6.5-7.2,反应器厌氧,恒温室温度控制在30±1℃。为使整个试验中同一水质条件下进行,进水采用化学合成培养基。This paper reports a Chlorobium Liwicola S1's isolation and identification. It is a strictly anaerobic and photosynthetic autotrophic bacterium. Along with sulfidedepondent CO2 assiwilaton,a few simple organic compounds can be photoassimilated. Acetate is most effectively used. Its best conditons of growth are 28-30℃,PH 6.5-7.0, and it contains hydrogenase. So it can live with methanefermentative bacteria in order to treat wastewater. At the same time, the treatment of wastwater using Chlorobium Limicola S1 with methane-fermontative bacteria under dark anaerobic and light anaerobic conditions is studied. In contrast with 1# reactor-darken, 2# reactor-illuminated can lossen wastewater's CODcr, BOD5 and on hance CH4 content better. In the test, 2# reactor's CH4 content is stable at 91.6%, but 1# reactor's is 87%. The CO2 content of 2# reactor is 4.5%, but 1# reactor's is 8.8%. When the load of teatment is 28.35g/l.d, the COD removal effficiency is 83.4% and the BOD removal efficiency is 74.53% in 2# reactor. They are separately 10.8%, 6.4% higher than 1# reactor's.