采用野外调查与样品分析法,探究了长沙县加拿大一枝黄花成片发生区、加拿大一枝黄花未入侵的水稻田(CK)、加拿大一枝黄花散生的灌木林地、化学防除加拿大一枝黄花后的试验田和加拿大一枝黄花发生区翻耕地5个样地在4种扰动方式(抛荒耕地、灌木林地、化学试验田、翻耕地)下加拿大一枝黄花对0～20 cm耕作层土壤的理化性质、主要微生物、养分和重金属含量的影响.结果 表明:与CK相比,加拿大一枝黄花成片发生地土壤pH值明显偏低,而化学防除后的试验田土壤pH值最高.样地中加拿大一枝黄花成片发生区土壤含水率和有机质含量均最高,分别达36.34％和9.49％.5个样地中土壤微生物数量存在显著差异,加拿大一枝黄花入侵样地中土壤细菌数均高于CK,灌木林地和化学试验田土壤真菌数较高,均达到了6×106 CFU/g以上,而加拿大一枝黄花成片发生区土壤真菌数最低,仅为2.60×106 CFU/g;5个样地中土壤放线菌数也存在差异.加拿大一枝黄花的入侵可以提高土壤养分含量,增加土壤肥力,且与入侵程度密切相关.加拿大一枝黄花生长密度越大,土壤全N、全P、速效K含量越高,分别为CK土壤的1.86倍、1.08倍、1.33倍.5个样地中,加拿大一枝黄花成片发生区土壤中Pb、Ni、Cu、Cd、Cr、Zn含量均为最高,土壤综合污染指数(Pzong)也最高.从污染程度上看,5个样地土壤中8种重金属元素单因子污染指数均低于1,均为无污染等级;综合污染指数(Pzong)为0.38～0.50,均为安全等级.说明不同扰动方式下加拿大一枝黄花对农业生产区土壤的理化性质、微生物量、养分和重金属含量的影响均存在明显差异.

为明确防除春季加拿大一枝黄花的最佳除草剂及其剂量,于2018年4月19-21日在湖南省长沙县郭公渡加拿大一枝黄花集中暴发地,选用2017年7月加拿大一枝黄花防除试验中效果最佳的4种典型内吸性除草剂、1种触杀性除草剂和3种助剂开展了春季加拿大一枝黄花化学防除试验.结果 表明,41％草甘膦异丙铵盐AS 1 756.50 g/hm2、25％环嗪酮SL 1 718.50 g/hm2、41％草甘膦异丙铵盐AS 769.20 g/hm2+农用有机硅增效剂600.00 g/hm2、25％环嗪酮SL 1 407.25 g/hm2+农用有机硅增效剂600.00 g/hm2、25％环嗪酮SL 1 407.25 g/hm2+乙基化和甲基化植物油1 800.00 g/hm2、41％草甘膦异丙铵盐AS 2 743.50 g/hm2 +48％三氯吡氧乙酸丁氧基乙酯EC 3 000.96 g/hm2和20％氯氟吡氧乙酸EC 150.00 g/hm2 +20％草铵膦AS 1 049.40 g/hm27组药剂处理对春季加拿大一枝黄花防效最佳,且用药量少.施药后30 d,试验小区内植株均出现根腐株,防效均达到100％,地上和地下鲜重防效分别达到78 ％、68％以上.这7组药剂组合可作为加拿大一枝黄花防除的典型药剂进行推广.与2017年夏季我们对加拿大一枝黄花化学药剂筛选结果相比,不仅提高了防效,还减少了用药量加拿大一枝黄花化学防治的最佳时期为春季.

于2018年7月25日-9月20日选用5种典型药剂与2种助剂对长沙县郭公渡成片发生区旺盛期加拿大一枝黄花进行了物理法联合化学法防除的田间试验.结果 表明,割除保留10 cm茬23 d后喷施41％草甘膦异丙胺盐AS 1 097.40 g/hm2+农用有机硅增效剂600.00 g/hm2、48％三氯吡氧乙酸丁氧基乙酯EC 900.48 g/hm2 +20％草铵膦AS 489.60 g/hm2、25％环嗪酮SL 687.50 g/hm2 +20％草铵膦AS 629.40 g/hm2与割除保留20 cm茬23 d后喷施25％环嗪酮SL 687.50 g/hm2+农用有机硅增效剂600.00 g/hm2、25％环嗪酮SL 687.50 g/hm2+乙基化和甲基化植物油1 800.00 g/hm2对加拿大一枝黄花的防效最佳,施药后34 d株防效均达到100％,地上与地下鲜重防效分别在78％、75％以上,且完全根腐,用药剂量也少.而30组药剂中除41％草甘膦异丙胺盐AS 1 097.40 g/hm2、20％氯氟吡氧乙酸EC 60.00 g/hm2 +20％草铵膦AS419.80g/hm2、48％三氯吡氧乙酸丁氧基乙酯EC 900.48 g/hm2+20％草铵膦AS 489.60 g/hm2三组低剂量药剂处理外,其他药剂的低剂量处理对留茬30、40、50 cm加拿大一枝黄花的防除均不能达到根腐.相关性分析结果表明,施药天数、施药剂量与施药后样方内腐烂株数呈正相关,而与施药后样方内植株平均地上、地下鲜重均呈负相关.

Six species of invasive plants in Hunan province were reported, in this work, as new records:Pluchea sagittalis (Lam.) Cabera, Ipomoea lacunosa L., Amaranthus palmeri S. Watson, Oenothera speciosa Nutt., Physostegia virginiana (L.) Benth. and Cortaderia selloana (Schult. & J. H. Schult.) Asch. & Graebn.. Among them, Pluchea sagittalis (Lam.) Cabera, Ipomoea lacunosa L., Amaranthus palmeri S. Watson and Oenothera spe-ciosa Nutt. are new recorded invasive plants in Hunan province for the first time. The other two species are potential invasive plants in Hunan province. This work also describes their growth habits, identifies characteristics and propa-gation properties, and then analyze and discuss their diffusivity and invasiveness. We put forward corresponding management strategies in the end.

Primulina hengshanensis, a new species of Gesneriaceae from the Danxia formation in Hunan Province, China, is described and illustrated. The new species is similar to P. langshanica, but has numerous diagnostic features that are outlined. It conservation status is assessed as VU (vulnerable) following IUCN criteria.

Four new invasive species from Hunan province were reported.They were Nasturtium officinale R.Br.,Gaura parviflora Dougl.ex Lehm.,Myriophyllum aquaticum Verdcourt and Thalia dealbata Fraser.Gaura parviflora Dougl.ex Lehm.was identified as a new record in invasive plants in Hunan province.The other three species were potentially invasive plants in the province.Furthermore,growth habit and biological characteristics,especially the propagation properties,of the four species were described.And suggestions for managing these invasive species were given based on analysis of their invasiveness and expansion trends.

A new species of Gesneriaceae, Primulina hunanensis, is described and illustrated from southern Hunnan, China. Morphologically, it is similar to P. cordata ( = Chirita cordifolia), but differs by having much larger leaves, broadly ovate or ovate bracts, 2–12 (–25)‐flowers, longer peduncle and purple corolla. It also resembles P. eburnea in the shape of the bracts and the colour of the corolla, but can be distinguished by longer petioles (9–25 cm long), cordate, ovate‐cordate or broadly ovate leaf lamina with rounded or obtuse apex, not entire leaf margin, and either cordate or deeply cordate leaf base. Detailed morphological description, diagnostic comparisons, habitat and micro‐morphology of seeds and pollen under SEM are presented.

This paper analyzed the currentstatus aboutthe invasion ofalien species in H unan Province and elaborated the reasons behind. Progresseson adm inistrating invasion ofalien speciesin H unan Province have been sum m arized.To preventthe issuesrelated to alien species invasion from deteriorating and to m ake sure they are undercontrol,w e proposed som e references to im plem entprevention counterm easures and search forstrategic rem edy,such as raising aw areness through enhanced publicity,strengthening supervision and m anagem entaccording to law , establishing the m echanism of m onitoring and early w arning, developing scientific and technological research, introducing consciousnessand responsibility ofdefending territories,increasing financialinvestm entand so on .

Agricultural wild plant resources and its endangered status quo in Hunan province were introduced at first. Then, the progresses in the protection of agricultural wild plants in Hunan province were expounded, and then the problems existing in its protection and management were analyzed, including protecting cognition needs to be improved; scientific research needs to be strengthened; financial input should be increased. Based on these, some countermeasures and suggestions for protection of agricultural wild plant resources in Hunan province were put forward, such as carrying out general survey and knowing resources; doing a good advertising and improving cognitions; doing monitoring and warning and understanding dynamics; making a layers of protection and establishing a grading area;perfecting system and strengthening supervision; scientifically researching and rationally using.

（续2012年第5期19页）巴西龟又名红耳龟、巴西彩龟、秀丽锦龟、麻将龟、七彩龟，原产巴西。巴西龟是世界公认的“生态杀手”。

<正>(续2012年第5期19页)巴西龟又名红耳龟、巴西彩龟、秀丽锦龟、麻将龟、七彩龟,原产巴西。巴西龟是世界公认的"生态杀手"。形态特征头较小,吻钝,头、颈处具黄绿相镶的纵条纹,眼后有1对红色斑块。背甲扁平,每块盾片

<正>(续第1期)豚草属菊科植物,又名艾叶破布草、美洲艾。原产北美洲,是一种影响人类健康和农牧业生产的危险性杂草。形态特征形态上为1年生草本,高20厘米～250厘米。茎直立,具棱,多分枝,绿色或带暗紫色,被白毛。下部(1节～5节)叶对生,上部叶互生,叶片三角形,裂片条状披针形,两面被白毛或表面

（续第3期）形态特征水葫芦属雨久花科、凤眼莲属,多年生浮水草本植物,高20厘米-70厘米。多须根,悬垂于水中（或根生于泥中）。茎极短,具长匍匐枝。叶基生莲座状,宽卵形或菱形,先端钩圆,基部浅心彤、截形、圆形或宽楔形。全缘，光亮。每株有叶6片-12片，叶柄长短不等，中下部膨胀成葫芦状的气囊。花莛多棱角，花序穗状，花蓝紫色。花期6月-9月，果期8月-10月。生物学特性水葫芦为多年生饲料和绿肥用作物，喜温、好湿，适于在静水或水流缓慢的水塘、沟渠生长，对酸、碱不敏感，对水质肥瘦和水的深浅要求不严格。抗寒力较强，一般只要温度能保持在7℃以上，就可以完全越冬。水葫芦分无性繁殖和有性繁殖，只要温度适宜，水葫芦就能持续不断地进行无性繁殖。

<正>(续2012年第4期14页)空心莲子草别名水花生、革命草等,属觅科多年生草本植物。形态特征茎基部匍匐、上部伸展,中空,有分枝,节腋处疏生细柔毛。叶对生,长圆

<正>(续第2期)假高粱是禾本科,高粱属植物,又名石茅、阿拉伯高粱、顾买草、宿根高粱。形态特征多年生草本,茎秆直立,高2米以上,具匍匐根状茎。叶阔线状披针形,基部有白色绢状疏柔毛,中脉白色且厚,边缘粗糙,分枝轮生。小穗多数,成对着生,其中一枚有柄,另一枚无柄,

<正>(续2012年第6期14页)红火蚁属昆虫纲膜翅目,蚁科,家蚁亚科,火蚁属。原分布于南美洲巴拉那河流域,本世纪初传入我国台湾省的部分地区。红火蚁是一种杂食性昆虫,主要危害农作物根、茎、叶和果实,当受到干扰时,会蜇刺人、畜。

依法管理外来物种已经势在必行。本文根据中国国情以及外来物种本身的生物性、经济性特点,就外来物种的概念、分类、引入行为的规范、引入风险评估的主要程序、外来物种的监测、外来物种的防治等问题进行了探索和分析。

南方稻田连作模式单一,盲目使用农药,稻田周边湿地淤积、废弃和填埋,致使面源污染消纳系统衰退,破坏了稻田生物多样性的发展空间.而生物多样性的破坏,已成为诱发稻田生物灾害的因素之一.目前,保护稻田周边湿地,构建稻田污染消纳系统;利用田埂荒地,构建生物群落;丰富连作模式,避免生物物种单一,对重建南方稻田的生物多样性具有十分重要的意义.

阐述了洞庭湖区农业面源污染的现状,在此基础上分析了农业面源污染所带来的危害,并提出了防治农业面源污染的对策与建议。

从分析湖南"粮-猪"产业链的形成和面临的冲击入手,提出随着粮食、生猪产量的增长,其废弃物和污染物也随之增长,并大大超出农村生态环境的承受能力;按照循环农业的发展思路,制定相关政策、执行行业标准,采用庭院型经济、猪沼稻循环、资源化利用、零排放生产、一次性施肥、无害化养殖、机械化操作等方式,可以控制"粮-猪"产业废弃物、污染物的蔓延和扩展。