长江河口九段沙下沙湿地植物N、P、K的分布特征与季节动态

2005年4—12月逐月对长江河口九段沙下沙湿地生态系统主要湿地植物群落进行样方调查与样品采集,通过对海三棱藨草(Scirpus mariqueter)、互花米草(Spartina alterni-flora)和芦苇(Phragmites australis)3种植物样品中N、P、K元素含量分析与生物量测定,揭示了下沙主要类型湿地的植物N、P、K元素的含量、分布、贮量与动态变化特征。结果表明:3种湿地植物N、P、K元素含量、分布、贮量与动态特征均各具特点。不同植物以及同一植物不同构件营养元素含量与分布均存在较明显的差异。营养元素在不同植物与同一植物不同器官含量排序的差异明显。N、P、K贮量分布特征因湿地植物种类、构件以及生物量不同而异。植物中营养元素含量与贮量的分布特征存在差异,其原因在于,与营养元素含量相比,生物量是制约植物营养元素贮量的主要因子。下沙湿地3种湿地植物及其构件的营养元素含量与贮量一般都低于上沙湿地。3种湿地植物营养元素均表现出明显的季节动态,一般生长初期营养元素含量高,生长停滞期含量低。3种湿地植物N、P、K含量的动态特征存在差异,总趋势为N、P、K含量随生长过程的进行而下降,相对下降速度排序为:KNP。受局地环境条件影响,上沙与下沙湿地的植物N、P、K元素的含量、分布、贮量与动态变化特征存在差异。     

长江河口九段沙互花米草湿地生态系统N、P、K的循环特征

研究了九段沙外来入侵种互花米草（Spartina alterniflora）湿地生态系统的营养元素含量、分布规律与循环特征。结果表明,九段沙的上沙、中沙和下沙互花米草湿地土壤全量养分含量差异相对较小,而速效性养分含量差异相对较大。土壤剖面中TK含量大大高于TN和TP含量,排序为:TK＞TN＞TP。各沙洲速效性养分含量排序为：速效K＞速效N＞速效P。土壤速效性养分与全量养分的空间分布规律并不一致,土壤剖面营养元素的垂直分布差异比较明显,速效性养分土壤剖面垂直分异比全量养分显著。各深度土壤营养元素含量均存在差异,不同沙洲同一深度土壤营养元素含量也存在差异。各沙洲不同深度土壤TN含量的差异明显大于TP和TK含量差异。植物中3种营养元素含量以K最高,N其次,P最低。湿地生态系统营养元素归还量远大于存留量。吸收系数排序为：N＞P＞K。不同沙洲营养元素的利用系数和循环系数存在明显差异,上沙P元素、中沙与下沙K元素利用系数最大,上沙K元素、中沙P元素与下沙N元素循环系数最大。     

植物与土壤微生物在调控生态系统养分循环中的作用

陆地生态系统的地上、地下是相互联系的。植物与土壤微生物作为陆地生态系统中的重要组成部分, 它们之间的相互作用是生态系统地上、地下结合的重要纽带。该文首先介绍了植物在养分循环中对营养元素的吸收、积累和归还等作用, 阐述了土壤微生物对养分有效性及土壤质量具有重要的作用。其次, 重点综述了植物与土壤微生物之间相互依存、相互竞争的关系。植物通过其凋落物与分泌物为土壤微生物提供营养, 土壤微生物作为分解者提供植物可吸收的营养元素, 比如共生体菌根真菌即可使植物根与土壤真菌达到互惠。然而, 植物的养分吸收与微生物的养分固持同时存在, 因而两者之间存在对养分的竞争。通过植物多样性对土壤微生物多样性的影响分析, 以及土壤微生物直接或间接作用于植物多样性和生产力的分析, 探讨了植物物种多样性与土壤微生物多样性之间的内在联系。针对当前植物与土壤微生物对养分循环的调控机制的争论, 提出植物凋落物是调节植物与土壤微生物养分循环的良好媒介, 植物与土壤微生物的共同作用对维持整个生态系统的稳定性具有重要意义。也指出了目前在陆地生态系统地上、地下研究中存在的不足和亟待解决的问题。     

杉木人工林养分循环随林龄变化的特征

为弄清杉木(Cunninghamia lanceolata)人工林不同林龄的养分循环特征, 为人工林丰产的经营管理提供科学依据, 利用湖南会同杉木林25年的定位连续测定数据, 根据杉木生长规律和养分吸收动态对杉木林不同林龄的养分循环进行了研究。结果表明: 对于同一林龄的杉木, 器官养分浓度大小依次为叶>枝>皮>根>干。林龄小于12年的, 杉木养分浓度随林龄增加而增高; 林龄大于12年的, 杉木养分浓度随林龄增加而降低。养分年均吸收量随林龄增长的变化曲线为双波峰。养分归还量随着林龄的增加逐渐增加。同一林龄, 各营养元素的利用效率都是磷(P) >钾(K) >氮(N) >镁(Mg) >钙(Ca)。林分郁闭后, 各营养元素的利用效率随着林木生长而增大。同一林龄, Ca、Mg的循环强度大于N、P, 各营养元素循环强度随林龄增长的变化曲线都为抛物线。同一林龄, N、P、K被杉木利用的时间比Ca、Mg长, 各元素被杉木利用的时间随着杉木生长的进行而缩短。研究显示: 不同林龄的养分吸收量除受生产量控制外, 还受这个林龄和前一个林龄杉木体内养分浓度的差异制约; 杉木体内养分再分配及贮备机制、杉木生长规律和不同生育阶段对养分的利用效率等共同调节控制着养分循环过程。     

土壤养分空间异质性与植物根系的觅食反应

植物在长期进化过程中,为了最大限度地获取土壤资源,对养分的空间异质性产生各种可塑性反应．包括形态可塑性、生理可塑性、菌根可塑性等．许多植物种的根系在养分丰富的斑块中大量增生,增生程度种间差异较大,并受斑块属性(斑块大小、养分浓度)、营养元素种类和养分总体供应状况的影响．植物还通过调整富养斑块中细根的直径、分枝角、节问距以及空间构型来实现斑块养分的高效利用．根系的生理可塑性及菌根可塑性可能在一定程度上影响其形态可塑性．生理可塑性表现为处于不同养分斑块上的根系迅速调整其养分吸收速率,从而增加单位根系的养分吸收,对在时间上和空间上变化频繁的空间异质性土壤养分的利用具有重要意义,可在一定程度上弥补根系增生反应的不足．菌根可塑性目前研究较少,一些植物种的菌根代替细根实现在富养斑块中的增生．菌根增生的碳投入养分吸收效率较高、根系增生对增加养分吸收的作用较复杂,取决于养分离子在土壤中的移动性能以及是否存在竞争植物;对植物生长(竞争能力)的作用因种而异,一些敏感种由此获得生长效益,而其它一些植物种受影响较小．植物个体对土壤养分空间异质性反应能力和生长差异,影响其在群落中的地位和命运,最终影响群落组成及其结构．     

三江平原湿地小叶章群落磷素积累动态与生物量动态分析

采用野外定位观测结合室内分析的方法,对三江平原典型小叶章湿地两种类型小叶章生长季磷的积累及植物生物量的季节动态进行研究,以揭示三江平原湿地中磷在植物中积累的季节动态变化及其与植物生物量积累之间的关系,进一步认识磷在湿地系统中通过植物吸收迁移转化的机制。结果表明,两种小叶章群落地上、地下生物量以及植物体磷储量有明显的季节动态变化,但二者季节变化特征不同。此外,植物体地上、地下部分磷素积累量和生物量在整个植物体所占的比重两种类型也存在一定差异,这与植物所处的生境及其生态适应有一定关系。分析两种小叶章群落的生长速率(AGR)以及磷素的积累速率(Vp),表明在生长初期,磷是植物生长的重要营养元素。两种小叶章的AGR、Vp的变化曲线相似,说明对于这两种小叶章群落,生境不是磷积累速率的主要影响因素。     

鄱阳湖湿地灰化苔草生长季氮磷含量与储量的变化

湿地植物在营养元素生物地球化学循环过程中起着重要作用,研究植物氮磷元素的吸收、分配和积累特征对于正确理解氮磷循环关键过程及其生态作用具有重要意义。基于野外实地观测和室内实验分析,研究了鄱阳湖淡水湿地灰化苔草春草生长季内不同部位生物量、氮磷含量及氮磷储量的动态变化。结果表明:在生长季内,灰化苔草各部位生物量随时间推移而增加,地上部分生物量在各生长期均高于地下部分,地下部分生物量积累速率相对稳定,而地上部分和总体平均积累速率表现为生长前期高于生长后期;各部位氮磷含量经历了先减少再增加的变化过程,其中地上部分氮元素在灰化苔草生长的中后期显著高于地下部分,而磷元素在中前期两者差异更为显著;生物量与氮磷储量均呈显著正相关,是灰化苔草氮磷储量动态变化的主导因子,氮磷元素主要储存在灰化苔草的地上部分;研究期间灰化苔草平均氮磷比介于3.32—3.83之间,按营养限制理论进行判断,氮元素可能是灰化苔草生长的限制性营养因子。     

九段沙上沙湿地植物N、P、K的分布特征与季节动态

2005年4-12月逐月对长江口九段沙上沙湿地生态系统主要植物进行定位样品采集与生态环境因子监测.通过对该区典型湿地植物群落海三棱蔗草(Scirpusmariqueter)、互花米草(Spartina aherniflora)和芦苇(Phragmites australis)3种植物样品中N、P、K元素含量的分析,揭示了上沙主要类型湿地植物N、P、K元素的分布特征与季节变化规律.结果表明:3种湿地植物N、P、K元素分布特征不同,不同植物以及同一植物的不同构件营养元素含量随植物生长节律发生变化.植物中元素贮量与含量之间分布特征并不相同,其原因主要在于生物量是制约元素贮量的主要因素,N、P、K贮量排序均为芦苇＞互花米草＞海三棱蔗草.不同构件营养元素含量的变化规律存在差异:4-5月茎中K含量逐渐减少,N含量呈现增加趋势;5-6月各构件P含量呈减少趋势;6-10月叶中N含量普遍高于其他构件.     

北京石灰性草甸土冬小麦营养元素生物循环的特点与锰、锌肥效应

 本文用盆钵试验研究京郊石灰性草甸土冬小麦养分生物循环的结果表明：小麦对不同养分吸收、携出和归还数量的差异很大。根据随籽粒携出和以根茬归还的比例特点,可将养分划分为三种类型：1)低归还高携出型(N、P、K);2)低携出高归还型(Ca、Fe);3)中归还中携出型(Mg、Mn、Cu、Zn)。施锰增加植株对氮和锰的吸收及钾和锰随籽粒的携出;施锌则降低植株对锰的吸收和随籽粒携出的钾、钙、镁、铁、锰量。锰肥和锌肥有拮抗作用。     

亚热带红壤侵蚀区马尾松针叶养分含量及再吸收特征

叶片衰老过程中的养分再吸收是植物适应养分贫瘠生境的一种重要策略,一直是生态学领域的研究热点。以亚热带红壤侵蚀区生态恢复先锋树种马尾松为研究对象,分析4种不同恢复水平下马尾松叶片养分含量随叶龄的变化情况及养分再吸收特征。结果表明:(1)叶片中N、P、K含量变化范围分别在(6.10±0.52)—(12.02±0.85)mg/g、(0.17±0.03)—(1.02±0.01)mg/g、(1.58±0.49)—(9.46±0.90)mg/g,随叶龄增长整体呈先增加后降低的趋势,具有一个快速积累期和一个相对漫长衰减期的动态特征,这表明叶龄也是影响叶片养分含量的重要因素;(2)叶片N、P、K含量随生境恢复水平的提高而增加,且N、P含量在除凋落叶外的叶龄阶段均表现出显著正相关,表明叶片中这两种营养元素在动态变化上存在协同性;(3)在叶片N、P、K再吸收效率中,P、K再吸收效率较高,而N相对较低。养分再吸收受生境中营养元素的含量水平、循环方式等因素的综合影响表现出一定选择性,对生境中较为贫瘠或使其生长受到限制的元素具有较高的再吸收效率。这不仅可以减小植物对外源养分的依赖性,同时也维持了体内重要营养元素的平衡。随叶龄增长叶片中N/P逐渐增大,反映出在叶片衰老过程中对限制元素P具有较强的再吸收能力,这种反馈调节提高了马尾松对养分贫瘠环境的适应性。本文的研究结果可为亚热带红壤侵蚀退化区先锋物种在贫瘠生境条件下的养分利用机制与适应对策方面的研究提供理论依据。     

橡胶人工林养分循环通量及特征

对不同树龄的PR107无性系橡胶人工林N、P、K 3种元素的养分循环通量及特征进行了研究.结果表明:(1)橡胶林生态系统养分循环通量中养分总吸收量为315.28～949.13 kg/hm2,总存留量为282.78～714.51 kg/hm2,总归还量为32.50～205.74 kg/hm2,胶乳总损失量为10.18～37.73 kg/hm2,土壤中养分总输入量为111.73～652.79 kg/hm2,总输出量为315.28～949.13 kg/hm2,平均亏损量为-249.94 kg/hm2,各循环通量都随着树龄的增加而增大,其中3种养分元素的大小顺序均为N>K>P;(2)胶林生态系统养分循环特征参数中吸收系数随林分生长呈凸抛物线变化(先增大后减小),归还系数逐渐上升,存留系数不断下降,周转时间加快,而6a后,胶林的枯落物养分平衡指数与土壤养分平衡指数开始下降,胶园土壤养分收支失衡,另外,产胶对养分的利用效率在14a前后表现为先升高后降低;(3)不同元素循环特征参数有差异.吸收系数、归还系数中的大小顺序为N>P>K,存留系数为K>P>N,枯落物养分平衡指数为K>N>P,土壤养分平衡指数为P>N>K,养分利用率为P>K>N,表明N的流动性大,故循环速率最快,循环水平最高,其次是K,而P的循环速率最慢,水平最低.     

基于SOFM网络对黄土高原森林生态系统的养分循环分类研究

对森林生态系统进行分类是认识森林生态过程的根本途径,传统的从结构角度对森林生态系统分类只能反映森林的外在特征,而无法从功能角度区别森林的本质差异.通过对黄土高原3个生物气候区18个不同森林生态系统的养分循环特征测算和分析,选取了能全面反映养分的积累和分布(生物量、枯落物积累量、养分积累量)、循环通量(年吸收量、年存留量、年归还量)以及养分循环效率(循环系数、利用系数、养分生产力)等多方面指标作为分类指标体系,利用自组织映射特征网络(SelfOrganizing Feature Maps,SOFM)聚类方法,从养分循环的角度将黄土高原森林生态系统划分为2个一级类型,6个二级类型.该分类结果与实际较符,从而探索了森林生态系统的功能分类方法,也验证了SOFM网络模型应用于森林养分循环分类的可行性.     

Plant growth and nutrient removal in constructed monoculture and mixed wetlands related to stubble attributes

The aim of this study is to test the hypothesis that it depends on plant species used in the wetlands and their stubble growth attributes, as to whether monoculture or mixed wetland is superior in plant growth and nutrient removal. Monoculture and mixed wetland microcosms of five wetland plant species were studied. Significant differences in growth and aboveground biomass were found in the monoculture wetlands. Species that showed faster growth and larger biomass in monoculture wetland were also dominant in the mixed wetland. The mixed wetland exhibited similar biomass and root growth to the averages of five monocultures. ANOVA showed that there were very significant differences among the wetlands in removal rates of all the nutrients studied except nitrate nitrogen (NO₃-N) and chemical oxygen demand (COD). The removal rates from the mixed wetland were generally comparable to the highest removal rates from the monocultures. The species exhibited different stubble growth attributes, with some species showing increasing stubble growth and removal rates, while other species showing decreasing stubble growth and removal rates. The results indicated that in both monocultures and mixed constructed wetlands, growth and nutrient removal rates depended on plant species, and attributes of plant stubble growth affected overall growth and nutrient removal capabilities.     

去叶时间对半干旱草原植物养分回收和干草生产的影响

去叶时间对半干旱草原植物养分回收和干草生产的影响 养分回收是植物养分保存的重要策略,其对环境和管理变化的响应关系到生态系统的养分循环和生产。去叶(刈割)是影响草地植物养分回收和生产的重要途径,而去叶时间的影响尚不清楚。本研究以内蒙古典型草原生态系统为对象,设置早期去叶(生物量高峰期之前)、峰期去叶(生物量高峰期)、晚期去叶(养分回收开始后)和不去叶(对照)四个处理,探讨了去叶时间对植物养分回收和生产的影响。通过测定植物物种和群落水平氮(N)和磷(P)回收特征,量化了植物N、P回收通量以及凋落物归还通量和干草输出通量,并评估了不同去叶时间处理下割草草地系统干草产量和质量。研究结果显示,峰期和晚期去叶降低植物群落N、P回收度,而早期去叶则对二者无影响;不同去叶时间处理下植物N、P回收效率相对稳定,仅晚期去叶降低N回收效率。峰期和晚期去叶降低植物群落N、P回收通量和凋落物N、P归还通量,而早期去叶并不影响这些参数。去叶时间降低植物群落养分回收通量,但未改变植物根系养分储存,说明根系养分吸收增加可补偿养分回收通量的降低。草地干草产量和质量在峰期去叶处理下最高,晚期去叶处理下最低。本研究结果为割草草地生态系统养分循环提供了新见解,通过调整刈割时间可以平衡草原的保护与生产,在植物生物量高峰期之前割草可实现保护和可持续生产的双重目标。     

喀斯特峰丛洼地不同类型森林养分循环特征

以中国西南喀斯特峰丛洼地为研究区域用标准木法和收获法对人工林、次生林、原生林3个不同类型森林的6个代表性群落的生物量、营养元素生物循环量及循环特征进行了研究。结果表明:(1)不同类型森林群落乔木各器官的养分含量大小顺序为:叶枝根干,林下植被层和凋落物层的养分含量比较高,其含量普遍高于乔木层各组分,仅次于乔木叶片;各组分中营养元素以K、Ca最高,P、Mg最低;(2)3种类型森林间乔木层的养分积累量总规律表现为原生林(4540.30 kg/hm~2)次生林(2107.09 kg/hm~2)人工林(719.51 kg/hm~2),分别占林分养分积累量的88.30%、79.57%和62.60%;(3)3种类型森林生态系统养分总贮量相差不大,均主要集中在土壤层在各层分配格局有所差异;营养元素的年吸收量和年归还量均为次生林原生林人工林,年吸收量分别为:418.80、271.17和148.79 kg hm~(-2)a~(-1);年归还量分别为:182.98、111.43和43.37 kg hm_(-2)a~(-1);(4)不同类型森林养分利用系数总规律为人工林(0.35)次生林(0.20)原生林(0.10);循环系数则相反,为原生林(0.48)次生林(0.46)人工林(0.30);而周转时间为原生林(37.32)人工林(18.63)次生林(13.93)。喀斯特峰丛洼地土层薄,养分贮存能力差,森林养分循环能力相对较弱,沿着强、中、弱干扰递减梯度,3种类型森林养分利用效率和循环能力呈增长趋势。     

Effects and mechanism of plant litter on grassland ecosystem: A review

Plant litter is dead, above and below ground; organic material i.e. leaves barks, needles, twigs and roots. Plant litter plays a key role in nutrient cycling and community organization in grassland ecosystems. Litter can have important consequences on recruitment of plant species through modification of biological, physical, and chemical features of microenvironment. Plant litter offers a major input of organic matter to the soil which modifies soil chemistry, hence impacts nutrient cycling. At early stages of litter decomposition, a particular amount of carbon is transporting to the soil nutrient pool. In terrestrial ecosystems, plant litter regulating biogeochemical cycles, maintain soil fertility, nutrient availability, and therefore influence plant growth, diversity, composition, structure, and productivity. Litter can also impact plant above net plant productivity and below net plant productivity in grassland ecosystem. Plant litter accumulation and decomposition can impact plant species composition and community structure through temperature, light and nutrient availability. The effects of plant litter on vegetation may be negative, positive or neutral due vegetation variability, study duration, habitat, latitude, quantity and quality of litter. These diverse effects of plant litter on grassland ecosystem might be due to, management practice type, management intensity, climate type, timing, precipitation and soil nutrient pool etc. Current review attempts to describe prominent effects of plant litter on vegetation, seed germination, soil fertility, Productivity, species composition, community structure and mechanism in grassland ecosystem.     

Root exudates of wetland plants influenced by nutrient status and types of plant cultivation

The present study investigated the amounts of root exudates and composition of organic acids released from two wetland plants (Typha latifolia and Vetiver zizanioides) under two nutrient treatments: low level (0.786 mM N and 0.032 mM P) and high level (7.86 mM N and 0.32 mM P) and two types of plant cultivation: monoculture and co-culture of the two plants. Low nutrient treatment significantly (p < 0.05) increased the root exudates of T. latifolia during the initial growth period (1-21 d) and those of V. zizanioides and the co-culture during the whole growth period. The concentrations of dissolved organic carbon in the root exudates of the co-culture in the low nutrient treatment were 3.23-7.91 times of those in the high nutrient treatment during the medium growth period (7-28 d). The compositions of organic acids varied between the two plant species and between the two nutrient treatments. The pattern of organic acids was also different between the co-culture and the monoculture. Oxalic acid was by far the major organic acid exuded from the two wetland plants. The present study on root exudates suggests that co-culture of wetland plant species would be more useful in the reclamation of waste water than a monoculture system.     

Effects of Eichhornia crassipes and Ceratophyllum demersum on Soil and Water Environments and Nutrient Removal in Wetland Microcosms

Wetland plants are important components that influence the biogeochemistry of wetland ecosystems. Therefore, remediation performance in wetlands can differ depending on the growth forms of plants. In this study, the effects of Eichhornia crassipes (floating plant) and Ceratophyllum demersum (submerged plant) on the wetland soil and water environments were investigated using a microcosm study with simulated hydrology of retention-type wetlands between rainfall events. The C. demersum microcosm (SP) showed the fastest recovery with a diel fluctuation pattern of dissolved oxygen, pH, and oxidation-reduction potential (ORP) from the impacts of nutrient inflow. Moreover, SP exhibited the lowest decrease in sediment ORP, the highest dehydrogenase activity, and more organic forms of nitrogen and phosphorus. E. crassipes microcosms exhibited the lowest water temperature, and efficiently controlled algae. In the presence of plants, the total nitrogen and phosphorus concentrations in water rapidly decreased, and the composition of organic and inorganic nutrient forms was altered along with a decrease in concentration. The results indicate that wetland plants help retain nutrients in the system, but the effects varied based on the wetland plant growth forms.     

A simulation model for nitrogen retention in a papyrus wetland near Lake Victoria,Uganda (East Africa)

Papyrus wetlands around Lake Victoria, East Africa play an important role in the nutrient flows from the catchment to the lake. A dynamic model for nitrogen cycling was constructed to understand the processes contributing to nitrogen retention in the wetland and to evaluate the effects of papyrus harvesting on the nitrogen absorption capacity of the wetlands. The model had four layers: papyrus mat, water, sludge and sediment. Papyrus growth was modelled as the difference between nitrogen uptake and loss. Nitrogen uptake was modelled with a logistic equation combined with a Monod-type nitrogen limitation. Nitrogen compartments were papyrus plants, organic material in the floating mat; and total ammonia, nitrate and organic nitrogen in the water, sludge and sediment. Apart from the uptake and decay rates of the papyrus, the model included sloughing and settling of mat material into the water, mineralization of organic matter, and nitrification and diffusion of dissolved inorganic nitrogen. Literature data and field measurements were used for parameterization. The model was calibrated with data from Kirinya wetland in Jinja, Uganda which receives effluent from a municipal wastewater treatment plant. The model simulated realistic concentrations of dissolved nitrogen with a stable biomass density of papyrus and predicted accumulation of organic sludge in the wetland. Assuming that this sludge is not washed out of the wetland, the overall nitrogen retention of the wetland over a three-year period was 21.5 g N m⁻² year⁻¹ or about 25% of input. Harvesting 10, 20 and 30% of the papyrus biomass per year increased nitrogen retention capacity of the wetland to 32.3, 36.8 and 38.1 g m⁻² year⁻¹, respectively. Although the nutrient flows estimated by the model are within the ranges found in other papyrus wetlands, the model could be improved with regard to the dynamics of detrital nitrogen. Actual net retention of nitrogen in the sludge is likely to be lower than 21.5 g N m⁻² year⁻¹ because of flushing out of the sludge to the lake during the rainy season.     

Leaf litter variation influences invasion dynamics in the invasive wetland grass Phalaris arundinacea

High litter mass is hypothesized to produce an invader-directed invasion by changing ecosystem properties such as nutrient cycling rates and light availability. An invasive plant species that stimulates litter accumulation may induce a positive feedback when it benefits from high litter conditions. Phalaris arundinacea is an invasive wetland grass that may induce positive litter feedback, as it produces abundant litter that varies in quality due to a wide range of foliar C:N content. In this study we investigated the range of growth responses within native and invasive genotypes of Phalaris that varied in initial foliar C:N levels (high C:N content was present in the invasive genotypes) when grown under varying litter mass. Overwintering with high litter reduced establishing tiller survivorship and the presence of litter delayed tiller emergence by 2 weeks. Overall, genotypes exhibited high trait plasticity in response to litter. Our results indicate that high litter mass can stimulate Phalaris growth, specifically for the genotypes with high initial C:N foliar tissue. Additionally, genotypes with initially high C:N ratios exhibited plastic responses consistent with a Master-of-some strategy indicating that their performance under high litter may depend upon the nutrient conditions under which they are grown. This study provides evidence for conditions that may lead to a positive feedback in Phalaris’ introduced range. Future studies should investigate how changing litter quantity alters nutrient cycling and competitor growth.