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1.
城市郊区外来杂草生态位特点及对生物多样性影响研究   总被引:4,自引:0,他引:4  
胡天印  黄华  郭水良  方芳 《广西植物》2007,27(6):873-881
采用样方法调查金华市郊春夏季节非农田生境的外来杂草和主要"土著性"杂草的种类和分布,分析外来杂草和其他主要杂草的生态位关系,定量分析了外来杂草对城市郊区植物多样性的影响。结果表明:(1)50个样地中共出现21种外来杂草,其中以野塘蒿、一年蓬、北美车前的生态位宽度最大,分别达到0.7819、0.6915、0.5237;(2)大致可将50种杂草分成3大类,其中21种外来杂草根据其对环境资源利用的差异又可分为4组;(3)人为干扰因素和土壤水分条件是影响外来杂草分布、危害的主要因素;(4)样地聚类群VI、I、III、II的外来杂草丰富度递增,并与物种丰富度成正比,说明外来杂草在一定程度上丰富了局部环境的物种多样性;(5)外来杂草重要值与物种丰富度呈线性显著负相关,表明金华市郊外来杂草的入侵对生物多样性有不利的影响;(6)外来杂草重要值较外来杂草丰富度更为适合衡量外来杂草对生物多样性的影响。  相似文献   

2.
采用水洗镜检法对江苏省31个农田样点(包括旱田和水田)0~15 cm土层土壤杂草种子库的种类组成和物种多样性进行了调查研究;采用典范对应法分析了杂草种子库种类与环境因子(包括淹水天数、土壤有机质含量、土壤pH、年降水量、年均温、样点经度和样点纬度)的相关性并绘制了样点和种类与环境因子的二维排序散点图.调查结果表明:在31个样点的土壤杂草种子库中共检测到杂草种子15科54种,旱田和水田各有41和45种,二者共有种类占多数但优势种有差异,通泉草[ Mazus japonicus (Thunb.) Kuntze]、异型莎草(Cyperus difformis L.)、水苋菜(Ammannia baccifera L.)、千金子[Leptochloa chinensis (L.) Nees]、棒头革(Polypogon fugax Nees ex Steud.)和牛繁缕[ Malachium aquaticum (L.) Fries]等种类为二者的共有优势种;杂草种类最多的为禾本科(Gramineae)和莎草科(Cyperaceae),分别占种类总数的22.6%和20.8%.旱田不同样点杂草种子库的优势种类变化较大,而水田杂草种子库优势种较稳定;二者优势种频度差异较大,旱田中频度高于0.30的杂草有19种,水田中频度高于0.50的杂草有20种;旱田和水田中平均重要值大于0.03的杂草各有11和9种,这些频度高的种类重要值也较大.旱田和水田土壤种子库种子密度分别为21 015和37 847 m-2,平均为31 008 m-2;旱田3层土壤中种子密度差异不显著,而水田上、中层土壤的种子密度显著高于下层.旱田以夏熟和秋熟杂草为主,而水田则以水田和夏熟杂草为主.按形态类型划分,水田及旱田中杂草种类数和密度从大到小均依次排序为阔叶草类、禾草类、莎草类,且水田中这3类杂草的种类数和种子密度均高于旱田.与旱田相比,水田杂草种子库的物种丰富度指数(S)、Shannon-Wiener 指数(H')和Simpson指数(D)较高,但Pielou均匀度指数(E)较低;旱田杂草种子库的S、H'和D指数随土层深度增加而降低、E指数逐渐升高,水田各土层的物种多样性指数则无明显变化趋势.第1种类排序轴与淹水天数负相关性最高(R=-0.8143),第2种类排序轴与年降水量和经度也有较高的负相关性;相关性分析和CCA分析结果均表明淹水天数是影响杂草种子库群落构成的最大因素.通过二维排序可将31个样点分为旱田和水田2大类,旱田可划分为长期旱连作和水旱轮作2个亚类;水田可划分为淮河以北地区和淮河以南长江流域地区2个亚类.研究结果说明:杂草种子库潜群落优势种与地上部农田杂草显群落优势种具有一致性,通过土壤杂草种子库的研究可以预测地上杂草的发生和危害情况.  相似文献   

3.
农田杂草是指生长于农田,妨碍农作物正常生长发育的非栽培植物。据调查我国主要农田杂草有500余种,它们或与作物争夺肥水、争夺阳光,或滋生病虫,或直接寄生于作物上,或分泌毒素抑制作物生长,甚至有些杂草还带毒直接影响人畜健康和安全。由于杂草比作物对环境的适应性强、繁殖快,因而成为农业生产的大敌。世界范围内农业生产每年受杂草危害损失达10%左右,仅美国每年由于杂草造成的谷物损失就达90—100亿美元。因此,农田杂草防除日益受到各国重视。 传统的防除杂草的方法是耕作防除,即依靠人力、畜力或机械动力牵引各种农具进行中  相似文献   

4.
农田杂草生态学与农业生产的关系吴万春,宁洁珍(华南农业大学)农田杂草生态学是研究农田杂草相互间、农田杂草与栽培植物以及与生存环境相互关系的科学。其研究目的在于阐明外界环境条件对农田杂草的形态结构、生理活动、化学成分、遗传特性和地理分布的影响;农田杂草...  相似文献   

5.
中国柽柳科植物花粉形态特征聚类分析   总被引:8,自引:2,他引:6  
张元明 《西北植物学报》2004,24(9):1702-1707
在观察了中国柽柳科(Tamaricaceae)4属27种植物花粉形态的基础上,对其进行了聚类分析。观察结果表明:该科植物花粉为三沟类型,无三拟孔沟类型,形态及外壁雕纹属间差异明显。花粉特征聚类分析结果表明,中国柽柳科植物花粉大致划分为明显的三组,所包含的种(某些种除外)分别隶属于柽柳科的4属:琵琶柴属(ReaumuriaLinn.)、水柏枝属(MyricariaDesv.)、山柽柳属(MyrtamaOvcz&Kinz.)和柽柳属(TamarixLinn.),而有争议的山柽柳属虽同柽柳属聚在一起,但也较早地分出成为独立的一支,结合种子形态及分子生物学证据,支持将秀丽山柽柳从水柏枝属中分出而另立新属,为传统分类学将该科划分为4属提供了依据。聚类分析进一步将水柏枝属植物花粉和柽柳属植物花粉分别分为2种类型,而琵琶柴属植物花粉类除个别种体积存在差异外,其纹饰类型较为单一,仅划分为1种类型。柽柳属植物花粉聚类分析结果与该属植物花盘类型的划分结果基本一致,融生花盘类型植物的花粉则在两组中均有出现,可能是间生花盘和假顶生花盘类型间的过渡类型。  相似文献   

6.
太白山北坡夏秋季鸟类物种多样性   总被引:6,自引:0,他引:6  
2006年5月~7月(夏季),9月~10月(秋季)在秦岭主峰太白山的北坡根据海拔和典型植被划分生境类型,在6种生境中选择典型样区划定样线并采用样线法对鸟类进行调查,根据鸟类的绝对数量和估算面积计算鸟类的绝对密度,并根据密度等级划分各生境类型中优势物种和常见物种。共观察到鸟类144种,其中留鸟102种,夏候鸟41种,冬候鸟1种。不同的海拔和不同生境类型中的鸟类物种丰富度和多度有较大差异,而且同一生境中鸟类多样性的季节性变化也很明显。无论是夏季还是秋季,低海拔农田带生境中鸟类的总密度最高,而高山灌丛草甸生境中的鸟类总密度最低。优势物种和常见物种在不同的生境类型组成也不相同,而且在不同季节也有变化。夏秋季的鸟类食性组成在农田带有显著差异,而其它生境类型中的鸟类食性夏秋季无明显差异,但是秋季植食性鸟类在各个生境类型中都有增多的趋势。物种丰富度和海拔梯度的关系显示在中海拔地区的鸟类丰富度最高。总体上,和20世纪80年代相比,太白山北坡的鸟类已经发生了明显的变化。  相似文献   

7.
农田杂草生态位研究的意义及方法探讨   总被引:28,自引:5,他引:23  
郭水良  李扬汉 《生态学报》1998,18(5):496-503
农田除草剂长期单一使用引起杂草种群的演变,增加了化学除草难度。预测除草剂作用下农田杂草群落的演变是当前迫切要求解决的问题。研究农田杂草生态位,揭示霜草种间生态心关系,结合杂草对除草剂敏感性资料,能够预测这种演变。本文以浙中油菜田为例,对该地区油菜田24种主要杂草的姓进行了七级目测,计测了它们的生态位宽度和生态位重叠值;汉生态位重叠值为指标,用极点排序和图论聚类分析中的最小生成树法,作出了反映杂草生  相似文献   

8.
田间杂草是在人们经常与之作斗争的情况下生长发展过来的,长期自然选择的结果,造成杂草具有多种多样的生物学特性,是一类适应性大而繁殖力又强的特殊类型的植物,具有和作物不断竞争的能力,比作物更能忍受较差的环境。杂草给农业生产带来不少危害,它夺  相似文献   

9.
王艳荣  赵利清 《生态学杂志》2005,24(12):1413-1417
2000~2002年对呼和浩特地区不同草坪的杂草种类组成及其危害进行了调查,发现在3个不同管理水平的草坪中共出现80种杂草植物,其中管理水平较差、中等、较好的草坪分别有67种、37种和36种杂草,以菊科、豆科、禾本科植物占优势,不同草坪杂草群落的生活型谱有明显差异.根据危害度指数把草坪杂草分为极度、重度、中度、轻度、弱度危害5个等级,极度和重度危害杂草在管理水平较差、中等、较好的草坪中的种类比例分别为11.95%、21.63%和22.22%;在管理水平较差草坪中,极度危害杂草是早开堇菜和止血马唐,春季和秋季以早开堇菜的危害为主,夏季以止血马唐为主;在管理水平中等草坪中,极度危害杂草是赖草和止血马唐,赖草的高危害期在春秋季节,夏季以止血马唐为主要危害杂草;在管理水平较好的草坪中,极度危害杂草是鼠掌老鹳草、鹅绒委陵菜、赖草、欧亚旋复花,其中鼠掌老鹳草的危害度在整个生长季中占绝对优势.  相似文献   

10.
南京市秋季外来杂草定量调查研究   总被引:16,自引:0,他引:16  
吴海荣  强胜 《生物多样性》2003,11(5):432-438
利用样方法调查了南京市不同生境下外来杂草的种类和分布情况 ,并用主成分分析法处理了数据。结果表明 ,南京市秋季外来杂草有 11科 19属 2 1种 ,以菊科最多 ,多数来自美洲。主成分分析结果表明 ,影响本市外来杂草分布、危害的主要因素是人为干扰强度和土壤水分条件。依据这两个因素的不同 ,样点可划分为 4个聚类群 :聚类群I包括的样点均分布于旱地农田 ,外来杂草以反枝苋 (Amaranthusretroflexus)、波斯婆婆纳 (Veronicapersica)和喜旱莲子草 (Alternantheraphiloxeroides)为优势种 ;聚类群Ⅱ的样点都是路边荒地等无人管理的或曾经是裸地的生境 ,以一年蓬 (Erigeronannuus)、野塘蒿 (Conyzabonariensis)和小白酒草 (Conyzacanadensis)为优势外来杂草 ;聚类群Ⅲ包含的样点以公园、景区为主 ,外来杂草种类最多 ,以豚草 (Ambrosiaartemisiifolia)、北美车前 (Plantagovirginica)、喜旱莲子草、钻形紫菀 (Astersubulatus)、一年蓬、野塘蒿和小白酒草等为优势种 ;聚类群Ⅳ的样点多是水边水田等土壤含水量较高的区域 ,优势外来杂草包括喜旱莲子草、钻形紫菀和南苜蓿 (Medicagohispida )。文章分析了各聚类群物种丰富度的差异 ,表明外来杂草的入侵对生物多样性有不利影响 ,最后对如何加强管理外来杂草提出几点  相似文献   

11.
The phytosociological researches which intent for studying the performance of weeds and the structure of weed assemblages associated with different crops derives their importance mainly from the adverse effect of weeds on crop productivity. Consequently, it is worth questioning about the ecological preferences of the weed growth in response to three main drivers for weed community structure associated with agronomic, and horticultural crops: crop diversification, crop seasonality, and soil type. A study area was selected comprising farmland of Nile Delta and its adjoining east and west territories, Egypt. A total of 555 species were recorded in 30 agroecosystems monitored and depending on species frequency/abundance values, 150 species were designated as the most influential weeds in weed community structure associated with agronomic and horticultural crops. The ecological preference of species for crop seasonality was evident through the results of Agglomerative hierarchical clustering. Three weed assemblage groups (WAG) identified: WAG A associated with winter agronomic crops, WAG B associated with summer agronomic crops, and WAG C associated with perennial agronomic crops and horticultural crops (orchards). Their diversity evaluated at different levels. The growth preference of the 150 species which were assigned as most influential weeds was gauged in response to the three environmental variables. 61 species were faithful to WAG A, 45 to WAG B, and 44 to WAG C. Concerning crop diversification, 34-species were significantly affected and scored coefficient of variation ≥ 100%. As for soil type, indicator species analysis revealed that 66-species show growth preference in fine grained soil while 84-species prefer coarse grained soil. In the three vegetation units (WAG A – C), 12 within-group associations (alliances) were specified of less-common (differential) species. The record of these alliances match to a specific environmental condition (ecological niche) and in them 29 strong indicators are identified. Redundancy analysis was used to extract and summarize the variation in species records in the response matrix (species vs. sites) that can be explained by the three different types of growth preference (explanatory variables), and the partial linear effect of them was evaluated by variation partitioning.  相似文献   

12.
作者创用了七级目测调查取样,进行数量分析的方法,对夏收作物田杂草群落进行分类研究,揭示了安徽沿江圩丘农区夏收作物田杂草群落的分布规律主要受土壤类型和轮作制度制约。看麦娘杂草群落分布于水稻土田,猪殃殃,野燕麦杂草群落分布于丘岗区旱地,卷耳、婆婆纳杂草群落分布于灰潮土旱地。首次提出综合草害指数,用以评定杂草群落类型中每种杂草的危害性,从而,提出了不同土壤类型和轮作制度的田块中恶性杂草的定量化指标与防除策略。  相似文献   

13.
The growth of crops and invading weeds were examined at six sites under different cultivation conditions in semi-arid Inner Mongolia, where sand dune reactivation has been controlled by weed invasion. The soil moisture content was not sufficient for crop growth in over-cultivated farmland. The shortage of moisture in the soil suppresses the growth of both crops and weeds. Accordingly, farmers carry out weeding to maintain better soil moisture conditions for crop growth. Over-cultivated farmland is often abandoned when the crop yield decreases to an economically unprofitable level. If weed vegetation before abandonment remains, it becomes a core of vegetation expansion and recovers the entire soil surface. While weedy vegetation is lacking or has been grazed by livestock, sand dune reactivation occurs.  相似文献   

14.
为了探明多年免耕下农田恶性杂草发生的机理,提高保护性耕作下作物对农田恶性杂草持久稳定的抑制效果,依据陕西安塞田间4a的定位试验, 采用小区调查取样和室内实验相结合的方法,从物种组成、密度特征、多样性以及相似性特征等方面,研究了黄土丘陵旱作农区大豆(Glycine max)、玉米(Zea mays)、红小豆(Semen Phaseoli)、马铃薯(Solanum tuberosum)在翻耕化肥(CF)、翻耕有机肥(CM)、翻耕无肥(CN)、免耕化肥(NF)、免耕有机肥(NM)、免耕无肥(NN)等水平下的农田土壤种子库.结果表明: (1) 4种作物24种土样中共萌发出12个物种1965株幼苗,隶属于7科12属.1年生杂草占94%,棒头草(fugax nees ex steud)、苋菜(Acalypha australis)、马唐(Digitaria sanguinalis)、早熟禾(Poa sphondylodes)为优势种,占87%.(2)在0~20cm土层不同处理间,土壤种子库的密度变动于(282.9±63.4)~(7482.5±1078.3)粒·m- 2,其中,红小豆小区>马铃薯小区>大豆小区>玉米小区;翻耕小区>免耕小区;有机肥小区>化肥小区>无肥小区,差异极显著. (3)土壤种子库密度NM红小豆最高,NN玉米最低;丰富度指数CF大豆为2.30;NN红小豆为0.29;多样性指数NN大豆为5.56,CF红小豆为0.45;生态优势度NF玉米为1.35,CF大豆为0.17.玉米、大豆是黄土丘陵沟壑旱作农区免耕下农田抑制杂草最为适宜的作物, NM玉米、NF大豆和NM大豆是黄土丘陵沟壑旱作农区较优的耕作管理方式,其农田的生态效应是能够竞争性抑制恶性杂草的蔓延,优化土壤环境,杂草的多样性高且比较均衡,杂草的土壤种子库密度低.  相似文献   

15.
Conventionally bred (CHT) and genetically modified herbicide-tolerant (GMHT) crops have changed weed management practices and made an important contribution to the global production of some commodity crops. However, a concern is that farm management practices associated with the cultivation of herbicide-tolerant (HT) crops further deplete farmland biodiversity and accelerate the evolution of herbicide-resistant (HR) weeds. Diversification in crop systems and weed management practices can enhance farmland biodiversity, and reduce the risk of weeds evolving herbicide resistance. Therefore, HT crops are most effective and sustainable as a component of an integrated weed management (IWM) system. IWM advocates the use of multiple effective strategies or tactics to manage weed populations in a manner that is economically and environmentally sound. In practice, however, the potential benefits of IWM with HT crops are seldom realized because a wide range of technical and socio-economic factors hamper the transition to IWM. Here, we discuss the major factors that limit the integration of HT crops and their associated farm management practices in IWM systems. Based on the experience gained in countries where CHT or GMHT crops are widely grown and the increased familiarity with their management, we propose five actions to facilitate the integration of HT crops in IWM systems within the European Union.  相似文献   

16.
Two surveys were conducted to investigate weed vegetation in a 153-hm^2 sampling area of summer crop fields from Anhui Province, China, through visual scoring of the level of weed infestation compared with summer crops on a seven-class scale. In total, 155 sampling sites were selected in the field based on crops, tillage, rotation systems, geographical regions, and soil types across the province. Data on weed communities and environmental factors were collected and analyzed through principal component analysis (PCA) and canonical correspondence analysis (CCA), and the output was interpreted ecologically. Results showed that the main factors influencing the structure and distribution of weed communities in summer crop fields were the soil submersion period, latitude, and soil type and pH. The CCA indicated a significant relationship between weed dominance and soil submersion duration, latitude, and soil pH. From the result of the PCA and CCA ordination, the 155 sampling sites could be divided into three groups based on geographic and floristic composition, as well as weed abundance. The southern dry land group, which was characterized by a double-cropping system in the hilly regions of southern and central Anhui Province with a continuous summer crop and an autumn dry land crop, was dominated by Galium aparine Linn. var. tenerum (Gren. et Godr) Robb., Avenafatua L., and Veronica persica Poir. The northern dry land group, which had the same cropping system as the southern dry land group, was dominated by G. aparine var. tenerum, Galium tricorne Stokes, Descurainia sophia (L.) Schur., and Lithospermum arvense L. in the North Anhui Province, China. These two dry land groups could be combined into one large dry land group, in which the Galium weed vegetation type dominated. The third group was the paddy soil group, which was characterized by a continu- ous summer crop and double- or triple-cropping systems of rice, and prevailed in the south and central areas of Anhui Province; Alopecurus aequalis Sobol. was the dominant weed in this group. Other main weeds in this group included Malachium aquaticum (L.) Fries, Stellaria alsine Grimm, Alopecurusjaponicus Steud., and Lapsana apogonoides Maxim. Thus, the weed community distributions in this group were described as the Alopecurus weed vegetation type. The paddy soil group could be divided into two subgroups, one southern and one central paddy soil subgroup. A strategy for integrated weed management is suggested according to the weed distribution pattern. The present study serves as a good example of how a quantitative research method was used to associate a visual estimate of weed infestation with multivariate analyses, such as PCA and CCA, and how this method can be applied to the study of weed vegetation on arable land.  相似文献   

17.
研究意义浙江金华地处浙江中部,旱地面积有5.09×104ha,占耕地总面积的18%以上,棉花、大豆、甘薯等秋旱作物是该地区重要的经济作物,几年来,由于农村劳动力转移,中耕除草减少,草害问题日趋严重。化学除草是解决旱田草害的有效方法。但是,除草剂的长期...  相似文献   

18.
Weeds are both harmful for agricultural production and an essential component of biodiversity in agricultural landscapes. Therefore, new cropping systems aiming at both maximising weed-related biodiversity and minimising weed harmfulness are needed. New cropping systems are now increasingly designed with weed dynamics models but these usually only consider weed densities or crop yield losses. The present paper proposed a set of indicators for assessing the impact on crop production and biodiversity of weed communities simulated with a cropping system model. Five harmfulness indicators were developed to take account of the criteria most frequently listed by farmers via an internet survey: (1) crop yield loss, (2) harvest pollution by weed seeds, stems and leaves, (3) harvesting problems due to green weed biomass blocking the combine, and (4) field infestation represented by weed biomass averaged over cropping seasons. A fifth indicator was added, i.e. (5) the increase in crop disease (i.e. take-all disease of cereals) in the presence of weeds. The biodiversity indicators were chosen in collaboration with ecologists. Two indicators reflect the weed contribution to vegetal biodiversity: (1) species richness and (2) Pielou's index for species equitability. Three other indicators were developed to assess weeds as a trophic resource for other organisms in the agro-ecosystems: (3) the number of weed seeds present on soil surface in autumn and winter to feed field birds, (4) lipid-rich seeds on soil surface in summer to feed insects such as carabids, and (5) weed flowers in spring and summer to feed domestic bees. These indicators were tested in a series of contrasted cropping systems identified in farm surveys and simulated with FlorSys. Analyses of variance showed that the cropping system and the crop sequence presented the highest impact on indicator values. Weather scenario and pedoclimate had little effect. Antagonisms and synergies between weed-related harmfulness and biodiversity were identified with Spearman correlations. Harmfulness indicators were all positively correlated, except for additional disease risk which was at best poorly correlated with other indicators. Most weed-related biodiversity indicators were also positively correlated, except species richness which was negatively correlated with species equitability, bird resource and insect resource. Weed harmfulness generally increased with increasing weed-related biodiversity. These correlations were though weak, and others were negative, showing that increased biodiversity could occur with decreased harmfulness (e.g. trophic resource for insects vs. yield loss or field infestation). Consequently, there are cropping systems that reconcile agricultural production and biodiversity.  相似文献   

19.
The use of remote imagery captured by unmanned aerial vehicles (UAV) has tremendous potential for designing detailed site-specific weed control treatments in early post-emergence, which have not possible previously with conventional airborne or satellite images. A robust and entirely automatic object-based image analysis (OBIA) procedure was developed on a series of UAV images using a six-band multispectral camera (visible and near-infrared range) with the ultimate objective of generating a weed map in an experimental maize field in Spain. The OBIA procedure combines several contextual, hierarchical and object-based features and consists of three consecutive phases: 1) classification of crop rows by application of a dynamic and auto-adaptive classification approach, 2) discrimination of crops and weeds on the basis of their relative positions with reference to the crop rows, and 3) generation of a weed infestation map in a grid structure. The estimation of weed coverage from the image analysis yielded satisfactory results. The relationship of estimated versus observed weed densities had a coefficient of determination of r2=0.89 and a root mean square error of 0.02. A map of three categories of weed coverage was produced with 86% of overall accuracy. In the experimental field, the area free of weeds was 23%, and the area with low weed coverage (<5% weeds) was 47%, which indicated a high potential for reducing herbicide application or other weed operations. The OBIA procedure computes multiple data and statistics derived from the classification outputs, which permits calculation of herbicide requirements and estimation of the overall cost of weed management operations in advance.  相似文献   

20.
Weed invasions are an increasing threat to the extensive wetlands of the Northern Territory's wet-dry tropics. Although the conservation value of these wetlands is in some ways undisputed, it is evident from the Government's multiple land use policy that it is also misunderstood. This policy aims to maximise economic returns from wetlands while protecting their ecological integrity at a time when ecological and economic costs associated with weeds are, at least in the short term, set to worsen. The underlying reasons behind wetland loss and degradation in Australia parallel those identified in Mediterranean Europe where there was antipathy from bureaucracies toward science and ecology. Several case studies from the Northern Territory explore how ecological, anthropogenic, political and economic factors contribute to weed problems. Caution is necessary when translating experience from agricultural weeds to environmental weeds. Managers have not always heeded the advice of specialists and practitioners, whose understanding of the ecological basis to weed invasions is not in as parlous a state as sometimes thought. Even when faced with sound information from which to manage, it was non-ecological reasons that slowed down or prevented effective weed control. If the floristic identity and diversity of Australia's natural wetlands is to be retained, then weeds need serious and immediate attention. Weed impacts progress beyond loss of wetland habitat and biodiversity to regional changes in landscape processes. We advocate that governments and industry recognise and address the underlying non-ecological reasons that exacerbate weed problems and set priorities to fund relevant practical studies and control programs that enable inventive weed management. Cooperation between land users, custodians and the wider community can help to overcome bureaucratic obstacles and enable judicious weed control that contributes effectively to wetland protection.  相似文献   

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