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1.
黄河三角洲外来入侵物种米草对滩涂鸟类的影响   总被引:1,自引:0,他引:1  
2005年5,8,10月份分别对黄河三角洲米草分布区与非米草分布区的无棣岔尖、东营市五号桩、小清河口的鸟类作了调查,并辅以2000年黄河三角洲湿地鸟类调查资料,研究了米草入侵对鸟类的影响。结果表明:米草入侵已导致黄河三角洲调查区鸟类种数减少,多样性降低,群落组成和结构发生变化,主要原因是米草入侵使鸟类觅食、栖息生境减少或丧失。  相似文献   

2.
本文报道了对山东省曲阜市蝴蝶资源及其生态调研的结果。通过作者两年多的采集调查,共获得蝴蝶标本700余号,经整理、鉴定后确认它们隶属于6个科、38种,并总结了曲阜市蝴蝶种类的优势种和稀有种,此结果为预防和控制各种害虫的发生与蔓延,为山东省昆虫资源的多样性保护提供了有益的资料。  相似文献   

3.
一、四川省的虾类四川省的虾类过去仅有零星报道,经过几年水产资源的调查,在收集到的大量虾类标本中,已鉴定出10种,隶属于4属2科;其中常见的优势种有中华米虾、朝鲜米虾、掌肢米虾和日本沼虾4种(尚有部分疑难标本未进行鉴定)。名录如下:  相似文献   

4.
川芎常见病虫害种类及防治方法   总被引:1,自引:0,他引:1  
调查了危害川芎的主要病虫害种类及其发生规律,对病菌标本与害虫的蛹、幼虫、成虫标本进行了鉴定。鉴定出川芎病害2种——根腐病、白粉病;虫害5种,除川芎茎节蛾和宽褐齿爪鳃金龟(蛴螬)外,朱砂叶螨(红蜘蛛)、烟草甲、咖啡豆象为首次报道,并介绍了传统防治方法。  相似文献   

5.
人工湿地植物处理污水的试验研究   总被引:21,自引:1,他引:21  
为了选择适合在中国四川地区生长的湿地植物,作者在四川省成都市1993年10月2日-11月19日的深秋季节进行了湿地系统处理模拟污水的盆栽静态试验,以研究多种湿地植物在自然环境条件下对污染物的去除情况。试验发现,灯蕊草,芦苇,菖蒲这三种植物在14天内均能去除模拟水样中的CODcr,其中,芦苇的去除率为38%,菖蒲的去除率为41%,灯蕊草的去除率为42~46%。这三种植物同时也能污水的pH从3.5调节  相似文献   

6.
世界野双峰驼各分布区食性分析   总被引:4,自引:1,他引:4  
野双峰驼在世界上仅分布于中国塔克拉玛干沙漠东部、罗布泊北部戛顺戈壁、阿尔金山北麓及中蒙边境地区外阿尔泰戈壁。这4个分布区环境条件相似;干旱、水份条件差、沙漠化和盐渍化严重、植被荒漠化特征显著。考察采集了4个区域的26个植物及86个野驼骆粪便,用镜检方法进行了分析统计,得出了各分布区野骆驼优先选择、不喜选择及拒绝选择的植物种类,得知食性与环境条件密切相关,野骆驼在外阿尔泰戈壁喜食针茅为主的植物,在其它分布区则以食用芦苇为主。  相似文献   

7.
通过生态浮岛在水面上种植了油菜、牛皮菜、旱伞草、美人蕉、空心菜、芦苇、春羽等7种植物,经过治理,实验水体质量得到较大改善。对生物量较大的油菜、空心菜、旱伞草、芦苇及美人蕉,通过植株体氮磷含量及植株鲜重,反推植物污水处理能力,经过测算,每平方米浮岛上种植的油菜、空心菜、旱伞草、芦苇及美人蕉在整个生长周期中按总磷计所能处理的污水(Ⅴ类至Ⅲ类)体积分别为23.6m^3、77.2m^3、27.27m^3、103.2m^3、22.2m^3。  相似文献   

8.
《环境教育》2008,(7):82-82
巨柏 裸子植物 柏科 国家二级保护野生植物 巨柏是1974年在西藏东部发现的一种特有植物,分布区狭窄。现有林木的年龄多在百年以上,其中有些是千年古树。常绿大乔本,高25—45米,胸径达1—3米,树皮条状纵裂;生鳞叶的枝排列紧密,常呈四棱形。分布区地处印度洋潮湿季风沿雅鲁藏布江河谷西进的路迳,但强度已减弱,而西部高原干旱气流的影响却逐渐占优势。  相似文献   

9.
金塔斯自然保护区位于新疆北部阿尔泰山中段。通过调查和文献整理,初步列出脊椎动物5纲、26目、61科、113属,约158种。其中有鸟类IOZ种,兽类34种,两爬类8种,鱼类14种。受到国家和自治区重点保护的动物约36种,占种数的23%。  相似文献   

10.
本文报道了对山东省曲埠市蝴蝶资源及其生态调研的结果。通过作者两年多的采集调查,共获得蝴蝶标本700余号,经整理,鉴定后确认它们隶属于6个,并总结了曲阜市蝴蝶种类的优势种和稀有种,此结果为预防和控制各种害虫的发生与蔓延,为山东省昆虫资源的多样性保护提供了有益的资料。  相似文献   

11.
天津塘沽作为滨海新区核心区,是目前天津发展最快的地区之一。由于本区盐碱土壤等自然条件,污水中盐分含量较高,制约了废水的回用。本文通过模拟人工湿地实验,比较了芦苇(Phragmites australis)、盐地碱篷(Suaeda salsa)、碱蒿(Artemisia anethifo原lia)、黄花鸢尾(Iris wilsonii)、盐角草(Salicornia europaea)和大米草(Spartina anglica)等耐盐植物对轻污染水体中高浓度氯离子的去除能力,筛选出去除能力较强的植物,并确定植物对盐分去除率达到最大时的生态系统条件。结果表明,适合人工湿地的耐盐碱植物对氯离子的去除效果依次为:芦苇>盐地碱篷>碱蒿>黄花鸢尾>盐角草>大米草,停留时间一般在第4d时可达到平衡。该研究为利用人工湿地处理高盐废水提供了科学依据。  相似文献   

12.
We studied the changes in wetland habitats and waterbird communities between the 1980s and the 2000s at Chongming Dongtan, a Ramsar site in the Yangtze River estuary, an ecologically important region. This region is an important stopover site for shorebirds along the East Asian–Australasian flyway and is extensively used by waterfowl. A net loss of 11% of the wetland area was estimated during study periods at Chongming Dongtan. The change was dependent on wetland types: while the area of artificial habitats such as paddy fields and aquacultural ponds more than doubled, more than 65% of natural habitats including sea bulrush (Scirpus mariqueter) and common reed (Phragmites australis) marshes were lost over the two decades. An exotic plant species introduced from North America, smooth cordgrass (Spartina alterniflora), occupied 30% of the vegetated intertidal zone by the 2000s. Although waterbird species richness did not change between the 1980s (110) and the 2000s (111), 13 species found in 1980s were replaced by 14 newly recorded species. Moreover, there were more species with declining trends (58) than with increasing trends (19). The population trends of species were affected by residential status and habitat types. Transients, wintering migrants, and habitat specialists were more likely to show declining trends compared to those breeding at Dongtan (including year-round and summer residents) and habitat generalists. Furthermore, species associated mainly with natural wetlands were more likely to decline than those associated mainly with artificial wetlands. These patterns suggest that the loss and change of wetland habitats at Chongming Dongtan adversely affected local population dynamics and might have contributed to the global decline of some waterbird species. Because Chongming Dongtan provides stopover and wintering habitats for many migratory waterbirds, protection and restoration of natural wetlands at Chongming Dongtan are urgently needed.  相似文献   

13.
Spartina alterniflora was transplanted into dieback areas of a salt marsh in southeast Louisiana at two elevations (ambient and +30 cm) with and without macro- (N, P, and K) and micronutrient (Fe, Mn, Cu, and Zn) additions to determine if transplant success is dependent on increasing elevation or nutrients.Spartina alterniflora transplanted into elevated plots had more than twice the above- and belowground biomass as compared to nonelevated plots after three months of growth. Additionally, there was significantly more vegetative reproduction (greater culm density and number of newly produced culms) in elevated plots as compared to plots at ambient elevation. Macronutrient additions increased culm densities only in elevated plots.Spartina alterniflora transplanted into nonelevated plots had lower survival rates even when transplants received nutrient additions. These results suggest thatS. alterniflora may be transplanted successfully into degraded salt-marsh areas if elevation is increased. The addition of nutrients without a concomitant increase in elevation is not sufficient for transplant success.  相似文献   

14.
Roots of salt marsh plant speciesSpartina alterniflora, S. patens, Distichlis spicata, and others were examined for the presence of vesicular-arbuscular mycorrhizal (VAM) fungi. Samples were taken from introduced planted material in a salt marsh restoration project and from native material in adjacent marsh areas along the Indian River, Clinton, Connecticut, USA. After ten years the replanted area still has sites devoid of vegetation. The salt marsh plants introduced there were devoid of VAM fungi, while high marsh species from the adjacent undisturbed region showed consistent infection, leading the authors to suggest that VAM fungal infection of planting stocks may be a factor in the success of marsh restoration.  相似文献   

15.
An ecological and recreational use survey was made of the Luxapalila River in Mississippi. This study was made before channelization work was started by the Army Corps of Engineers. A follow-up study is planned after channelization work is completed. Four stations were located along a 10.5 mile stretch of river where certain chemical and biological measurements were taken during the four seasons of the year. The results of this study revealed that the river is an unpolluted, biologically productive waterway relatively high in chemical constituents. Eleven families and 37 different species of fish were collected. Biomass measurements of standing crops of invertebrates ranged from a low of 0.11 grams oven dry weight per square meter to a high of 18.89 grams per square meter, with larger biomass collected from eddy areas than from riffle areas. A survey of recreational use of the river indicated relatively light use was made of the river. Fishing was the major use followed by swimming.  相似文献   

16.
贵州桦木资源现状与开发利用策略   总被引:1,自引:0,他引:1  
贵州桦木种类有7个,其中桦木属有4个种,桤木属有3个种。光皮桦和旱冬瓜是分布最广的两个种,全省各地均有分布。传统林业主产区的现有桦木资源数量比非主产区小,现有桦木资源以中、幼林为主,中、幼林的面积和蓄积超过98%,近、成熟林和过熟林资源相对非常少。贵州桦木资源开发利用应系统开展良种选育研究,加强抚育管理、综合改造"三低"林分,科学规划、合理布局良种基地,采用良种良法营造高效用材林基地。  相似文献   

17.
盐碱苇塘广泛分布于东北松辽平原地区,是该区域宜渔国土资源的主要类型之一.根据松辽平原农业综合开发和国家“八五”科技攻关的生产实践,本文以吉林省西部的大安市叉干镇科技试验示范区为例,初步介绍了盐碱苇塘资源渔业开发的5项关键技术措施,以供同类地区借鉴.  相似文献   

18.
An important population of the critically endangered pearl mussel Margaritifera margaritifera (Linnaeus, 1758) was surveyed at the edge of its southern distribution (River Paiva, Portugal). Although an earlier study suggested that this population had a very low number of individuals (<500), a narrow distribution, and was mainly comprised by old specimens our data contradict these findings. Our assessment estimated a population with probably more than 5,000 individuals distributed across 80 km of the river length. From the 32 sites surveyed, 19 contained M. margaritifera with higher abundances verified in the middle and upper parts of the river (a maximum of 78 ind. per 100 m of river stretch was recorded). The pearl mussels showed a clear preference for areas near the banks, in shallow water, sandier and gravel sediments, and a high degree of riparian vegetation cover. The population structure was skewed with a very high percentage of large (and old) animals but 3.7 % of the individuals collected were juveniles (<60 mm in length); therefore, this population can be considered functional. Environmental characterization indicated that this river is still in excellent or good condition although some areas showed deterioration due to discharge of domestic effluents. The main conservation requirements of M. margaritifera in the River Paiva include maintaining the water quality (and if possible stopping the discharge of domestic effluents), increasing riparian vegetation cover, removing several weirs to increase connectivity, and increasing trout density.  相似文献   

19.
The Kootenai River floodplain in Idaho, USA, is nearly disconnected from its main channel due to levee construction and the operation of Libby Dam since 1972. The decreases in flood frequency and magnitude combined with the river modification have changed the physical processes and the dynamics of floodplain vegetation. This research describes the concept, methodologies and simulated results of the rule-based dynamic floodplain vegetation model "CASiMiR-vegetation" that is used to simulate the effect of hydrological alteration on vegetation dynamics. The vegetation dynamics are simulated based on existing theory but adapted to observed field data on the Kootenai River. The model simulates the changing vegetation patterns on an annual basis from an initial condition based on spatially distributed physical parameters such as shear stress, flood duration and height-over-base flow level. The model was calibrated and the robustness of the model was analyzed. The hydrodynamic (HD) models were used to simulate relevant physical processes representing historic, pre-dam, and post-dam conditions from different representative hydrographs. The general concept of the vegetation model is that a vegetation community will be recycled if the magnitude of a relevant physical parameter is greater than the threshold value for specific vegetation; otherwise, succession will take place toward maturation stage. The overall accuracy and agreement Kappa between simulated and field observed maps were low considering individual vegetation types in both calibration and validation areas. Overall accuracy (42% and 58%) and agreement between maps (0.18 and 0.27) increased notably when individual vegetation types were merged into vegetation phases in both calibration and validation areas, respectively. The area balance approach was used to analyze the proportion of area occupied by different vegetation phases in the simulated and observed map. The result showed the impact of the river modification and hydrological alteration on the floodplain vegetation. The spatially distributed vegetation model developed in this study is a step forward in modeling riparian vegetation succession and can be used for operational loss assessment, and river and floodplain restoration projects.  相似文献   

20.
The Okavango Delta, the largest Ramsar wetland site, is one of the most resource-rich ecosystems in Botswana. A range of resources, including reeds, contribute in various ways to the well-being of many of the communities through subsistence and income generation. The economic value of reeds and other resources found in wetlands has been poorly understood, leading to the perception that wetlands are wastelands, and have little or no economic values. Such resources are therefore likely to receive lower priority in conservation when evaluated against other alternative activities. The aim of this research was to determine the benefit and financial and economic viability of harvesting river reed in the Okavango Delta. Primary data were collected through a structured questionnaire administered at three villages in the Okavango Delta. Secondary data were collected from existing literature. Financial and economic analysis was undertaken using static and financial models. Market prices were used to calculate the net income generated from the sale of harvested reed. The measurement criteria for static models were the annual net cash income, net annual economic benefit, and return on investment (ROI), while those under the dynamic models were the net present value (NPV), benefit cost ratio (BCR), and the net benefit investment (N/K) ratio. It was more financially profitable and economically viable to harvest and sell reeds at Shorobe village (a village relatively close to the District economic centre, Maun), than Shakawe or Etsha-13.  相似文献   

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