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1.
对中国飞蝗种下阶元划分和历史演化过程的几点看法   总被引:15,自引:1,他引:15  
前人把我国飞蝗划分为东亚飞蝗、亚洲飞蝗和西藏飞蝗三个亚种,并推测我国最原始的飞蝗发生地可能是郑州-开封东北至临清-禹南以南的古黄河冲积扇地带。由于飞蝗的形态、生理、生态等性状受气候与生态条件影响,从而在地区间变化很大,而且过去关于我国飞蝗发生动态和演化的分析均忽视了地史中重大气候事件的影响,因此有关结论的可靠性值得质疑并有待深入验证。根据分子群体遗传学的最新研究结果,我们认为:(1)我国飞蝗应被重新划分为青藏种群、海南种群和北方种群3大类群;(2)我国东部地区(辽宁、黄淮平原、陕西和山西)的飞蝗与海南的飞蝗之间的遗传差别已达亚种水平,因此不是东亚飞蝗,而是亚洲飞蝗经过适应性演化在我国华北地区形成的特异地理宗——华北地理宗;(3)华北地理宗的形成应是末次冰期后种群大规模扩张的结果,推测是由蒙新高原的飞蝗沿黄河流域逐步扩散而来;(4)结合历史上飞蝗发生的情况可以推断,在中国,至少在北至北纬46℃的地区,光周期不会成为飞蝗发育的限制性因素,有效积温可能是惟一限制性气候因子。因此,在气候逐渐变暖的趋势下,飞蝗有逐渐向北扩散的可能,东北地区将会逐步具有飞蝗大发生所需要的必要气候条。  相似文献   

2.
亚洲飞蝗Locusta migratoria migratoria是中国新疆与哈萨克斯坦边境区域重要害虫之一,具迁飞性且繁殖能力强,对农牧业经济造成巨大伤害。本文以亚洲飞蝗为研究对象,根据其发生区和相关生物学特性,利用CLIMEX 4.0.2和ArcGIS 10.2相结合,预测其在新疆和中哈边境区域亚洲飞蝗的潜在地理分布。亚洲飞蝗的适生区在新疆境内集中分布在北疆(42.69~48.29°N),包括伊犁、博尔塔拉中部、塔城西北部及南部、阿勒泰西部、昌吉和乌鲁木齐南部地区;哈萨克斯坦境内主要分布在北纬47.03~51.65°N区域,包括东哈萨克斯坦州北部、阿拉木图州东南部境内的湖泊及河流沿岸地区,这与亚洲飞蝗的现有分布点和历史发生记录吻合。未来气候变暖情景下,亚洲飞蝗在中哈边境新疆境内的适生区逐渐扩大,其中在阿勒泰、伊犁、昌吉及乌鲁木齐的高度适生区面积增加,哈密开始出现高度适生区;在哈萨克斯坦边境区域的适生区略有增加,其中东哈萨克斯坦州地区高度适生区面积减少明显。研究结果对区域内亚洲飞蝗的预测预报和综合防控具有重要意义。  相似文献   

3.
中国散居型飞蝗地理种群数量性状变异的分析   总被引:9,自引:1,他引:8  
康乐  李鸿昌 《昆虫学报》1989,32(4):418-426
本文用模糊聚类分析、系统聚类分析和主成分分析的方法对中国21个散居型飞蝗Locusta migratoria L.Phase Solitaria地理种群的形态测量数据进行了数值分析.这3种分析方法所得的结果是相似的.结果较好地说明了我国21个飞蝗地理种群的地理变异、种群相互关系及亚种的地位.初步确定了我国飞蝗三个亚种的自然地理分界线.陕北的地理种群与陕中、南和华北平原的地理种群非常接近,应认为是东亚飞蝗 L. m. manilensis(Meyen)的一个地理种群.发生基地的散居型飞蝗与一般发生区或扩散区的飞蝗形态特征存在明显差异,作者认为,这是由于发生基地种群密度和生存条件经常处于不稳定状态的结果.主成分分析说明,内蒙古西部的地理种群是介于亚洲飞蝗L. m. migratoria L.和东亚飞蝗L. m. manilensis(Meyen)之间的过渡性种群,但更接近新疆和甘肃的亚洲飞蝗.作者还将E/F、F/C和P/C 3个比值投入运算,这不仅输入了体形的信息,而且也起到给前翅长E、后足股节长F和头宽C加权的作用.作者认为,当在空间和时间上大量连续取样的情况下,飞蝗形态测量学的方法对于确定亚种的地位是比较困难的,这是因为该种固有的多变性和散居型飞蝗在水平和垂直分布上的连续性所造成的.但对于分析地理种群的相互关系方面则显示出优越性.  相似文献   

4.
基于前人研究成果,对中国东亚飞蝗发生的孕灾环境及其主要影响生态因素进行辨识.结果表明:蝗灾的动态变化与气候变化关系密切;飞蝗分布界限受气候带的影响;发生基地具有类似的孕灾环境特征;飞蝗发生发展与水文、气候、土壤和植被等主要生态因素的一定指标阈值有密切关系;传统的飞蝗预测研究多着重分析各生态因子与飞蝗消长的数理统计相关关系,近年多在大尺度气候背景下探讨适宜中长期的预测方法,国内外利用遥感等多种现代化手段对蝗灾进行大范围监测.  相似文献   

5.
为探明亚洲飞蝗食物选择机制及寄主植物对其生长发育的影响,基于对比称重法、取食频数测定和人工饲喂方式,对亚洲飞蝗不同龄期食量变化、对不同寄主植物喜食程度及主要寄主植物对其生长发育的影响进行研究。结果表明:雌性飞蝗4龄至成虫阶段日取食量分别为0.39±0.02、0.50±0.02、0.75±0.07 g/d。雄性飞蝗4龄至成虫阶段的日取食量分别为0.30±0.06、0.41±0.03、0.71±0.11 g/d。同性别亚洲飞蝗不同发育阶段日取食量间均存在极显著差异。选取小麦、玉米、芦苇、早熟禾、苜蓿、冷蒿等植物,进行取食频数测定。亚洲飞蝗3龄蝗蝻喜食小麦和芦苇,少食苜蓿和早熟禾,偶食玉米,不食冷蒿。4龄蝗蝻嗜食玉米,喜食小麦,少食芦苇,偶食早熟禾,不食苜蓿和冷蒿;5龄蝗蝻喜食小麦,少食芦苇、玉米和早熟禾,偶食苜蓿,不食冷蒿。成虫喜食小麦和玉米,少食芦苇和早熟禾,不食苜蓿和冷蒿。分别以小麦、玉米、芦苇及三者同比例混合物饲养亚洲飞蝗3龄、4龄、5龄蝗蝻后,不同龄期蝗蝻发育历期、交配次数、产卵次数均存在极显著差异。亚洲飞蝗随着年龄段的增长取食量逐渐增加,而亚洲飞蝗同一发育阶段雌性与雄性取食量之间没有显著差异。亚洲飞蝗在每个年龄段对不同的寄主植物具有选择性,主要取食的寄主植物为小麦、玉米和芦苇。与单种饲料饲养相比,以混合饲料饲养的亚洲飞蝗发育历期最短,交配次数最少,产卵次数最多。不同寄主植物对其生长发育有显著的影响。  相似文献   

6.
一.引言 亚洲飞蝗(Locusta migratoria manilensis Meyen)(以下简称飞蝗)在我国沿海诸省每年一般发生两代。根据在洪泽湖与微山湖蝗区观察的结果,夏蝗在6月下旬和7月上旬产卵,至同年7月中、下旬孵化;秋蝗在9月上、中旬产卵,到次年6月上旬孵化。越冬蝗卵在土中停留8个月左右的时间,这使它们有充分的机会去领受当地环境因素如寒冷、干,湿、天敌等的作用,从而左右次年飞蝗发生时间  相似文献   

7.
飞蝗研究进展   总被引:11,自引:6,他引:11  
飞蝗作为农业重大害虫,其分布遍及欧洲、亚洲、非洲和澳洲。全世界共有10个亚种,我国有3个亚种。飞蝗不但分布广,而且数量多、发生频率高,危害极为严重。作者在查阅了国内外近20年文献资料的基础上,结合我国蝗害情况,分别从形态、组织、生理、生化、遗传、毒力及分子系统学等方面综述了国内外飞蝗的研究进展,以期对我国飞蝗的基础及应用研究提供参考。  相似文献   

8.
本文对亚洲飞蝗Locusta migratoria migratoria(L.)发声器的结构及鸣声的时域特征进行了研究.亚洲飞蝗主要的发声方式为前翅中闰脉-后足股节型,即前翅中闰脉的发声齿与后足股节内侧隆线相互摩擦发出鸣声.应用扫描电子显微镜技术对发声器的结构进行观察,结果表明,亚洲飞蝗前翅中闰脉具有单排规则排列的发声...  相似文献   

9.
亚洲飞蝗是中国农业上主要害虫之—,中国科学院昆虫研究所年来对此虫进行生理、生态、形态等各方面的研究,在组织学工作方面我们担任了不同饲料对於亚洲飞蝗消化系统和生殖系统组织构造的影响。当我们研究不同饲料对这两系统的影响  相似文献   

10.
气候及其变化对飞蝗发生期的影响   总被引:3,自引:0,他引:3  
利用环渤海2类典型蝗区飞蝗发生期资料和同期气候资料,对不同蝗区气候变化和飞蝗发生期的关系进行对比分析。结果表明:沿海蝗区和洼淀蝗区气候的差异是导致飞蝗发生期差异的重要因素,影响飞蝗发生期的主要气候因子为气温;沿海蝗区3、4月气温偏低0.2 ℃~0.4℃,导致夏蝗三龄期以前飞蝗发生期比洼淀蝗区偏晚2~3 d,沿海蝗区其他月份气温偏高,气温的累积效应导致夏蝗三龄期以后发生期偏早;秋蝗发生期变化幅度小于夏蝗,与入夏后气温变异系数小相对应;20世纪90年代以来2类蝗区气温变化幅度不同是导致飞蝗发生期变化幅度不同的主要原因,且夏蝗发生期早晚与3、4月气温高低密切相关。  相似文献   

11.
东亚飞蝗天敌——中国雏蜂虻的研究   总被引:4,自引:0,他引:4  
中国雏蜂虻Anastoechus chinensis Paramonov 是主要以幼虫取食东亚飞蝗Locusta migratoria manilensis(Meyen)蝗卵的重要天敌,隶属双翅目,短角亚目,蜂虻科Bombyliidae.蜂虻亚 科Bombyliinae,它是国内首次发现;研究其大面积的保护利用在国内外均属首例。中国雏蜂虻主要分布 在山东,河北,天津等省、市滨海蝗区,发生于蝗卵卵块的比率较高,一般年份在50%左右,高达75%以上。 它一年发生一代,以卵在蝗卵块内及附近土中越冬,翌年4至5月以幼虫吸取蝗虫卵粒汁液,对东亚飞蝗一代控制能力较强,有较高的保护利用价。作者从1982年至1987年间,对中国雏蜂虻的形态特征,生物学特性,生态学特性及其保护利用措施等方面进行了较系统的研究,并进行了大面积的保护利用工作,为生物治蝗开拓了新的途径。  相似文献   

12.
To help evaluate effects of Mississippi River inputs to sustainability of coastal Louisiana ecosystems, we compared porewater and substrate quality of organic-rich Panicum hemitomon freshwater marshes inundated by river water annually for more than 30 years (Penchant basin, PB) or not during the same time (Barataria basin, BB). In the marshes receiving river water the soil environment was more reduced, the organic substrate was more decomposed and accumulated more sulfur. The porewater dissolved ammonium and orthophosphate concentrations were an order of magnitude higher and sulfide and alkalinity concentrations were more than twice as high in PB compared with BB marshes. The pH was higher and dissolved iron concentrations were more than an order of magnitude lower in PB marshes than in BB marshes. The influx of nutrient-rich river water did not enhance end-of-year above-ground standing biomass or vertical accretion rates of the shallow substrate. The differences in porewater chemistry and substrate quality are reasonably linked to the long-term influx of river water through biogeochemical processes and transformations involving alkalinity, nitrate and sulfate. The key factor is the continual replenishment of alkalinity, nitrate and sulfate via overland flow during high river stage each year for several weeks to more than 6 months. This leads to a reducing soil environment, pooling of the phytotoxin sulfide and inorganic nutrients in porewater, and internally generated alkalinity. Organic matter decomposition is enhanced under these conditions and root mats degraded. The more decomposed root mat makes these marshes more susceptible to erosion during infrequent high-energy events (for example hurricanes) and regular low-energy events, such as tides and the passage of weather fronts. Our findings were unexpected and, if generally applicable, suggest that river diversions may not be the beneficial mitigating agent of wetland restoration and conservation that they are anticipated to be.  相似文献   

13.
洪泽湖蝗区东亚飞蝗发生动态的研究   总被引:4,自引:1,他引:3  
洪泽湖是我国四大淡水湖泊之一,也是黄淮平原上最大的自然蓄水库。解放前,由于湖水位不能控制,沿湖土地直接受湖水位升降的波及和湖水顶托的影响,不能常年耕种,滨湖滩地及内涝洼地均沦为季节性荒地,遍布荒滩草洼。因此,洪泽湖及其沿岸地区具备了飞蝗猖獗发生的生态地理条件而成为我国具有历史性的东亚飞蝗Locusta migratoria manilesis  相似文献   

14.
Fixation of river flow passages and riverbed degradation may facilitate the development of higher floodplains with the establishment of exotic species such as black locust (Robinia pseudoacacia L.). We quantitatively evaluated the relationship between nitrogen (N) levels in black locust trees and in sediments under different flood disturbance regimes in a riparian area of the Chikuma River. In this study, allometric equations were developed for relating leaf N content to diameter at breast height of black locust. The amount of leaf N in black locust increased with distance from the river, reaching 159 kg N ha−1 at 180 m from the river. There was a small difference in N content between green and fallen leaves (0.2%), and so the leaf N was almost equivalent to N input to riparian sediments. Fine sediments accumulated on the riparian area, where the amount of sediments N increased with distance from the river, ranging from 1091 ± 767 to 4953 ± 2953 kg N ha−1. The N accumulation rates also increased with distance from the river, corresponding with the amount of leaf N in black locust per unit area, but the former exceeded the latter. The sediment N accumulation might be accelerated by sediment trapping effect due to riparian vegetation itself. A large input of N provided by invaded black locust might alter nutrient dynamics and native plant community structure in the riparian area.  相似文献   

15.
丁岩钦 《昆虫学报》1995,38(2):153-160
本文系统地对海南热带稀树草原蝗区的生态地理结构特征进行了分析,说明本蝗区是 Uvarov(1936)提出的飞蝗两类蝗区理论中,由于森林破坏而形成的一类蝗区,作者将它定名为“热带稀树草原蝗区”。这类蝗区在我国过去尚缺乏研究。文中进而根据本蝗区的成因、生态特征以及对蝗区的生态控制对策,分别与我国大陆的东亚飞蝗大沙河类型蝗区进行了比较。  相似文献   

16.
本文系统地对海南热带稀树草原螟区的生态地理结构特征进行了分析,说明本蝗区是Uvarov(1936)提出的飞蝗两类蝗区理论中.由于森林破坏而形成的一类蝗区,作者将它定名为"热带稀树草原蝗区"。这类蝗区在我国过去尚缺乏研究。文中进而根据本蝗区的成因、生态特征以及对蝗区的生态控制对策,分别与我国大陆的东亚飞蝗大沙河类型蝗区进行了比较。  相似文献   

17.
1. At a local scale, the species composition, diversity and spatial variation of wetland plant communities are determined primarily by spatial and temporal heterogeneity in their environments. Less is known about variation at a landscape‐level. The floodplain of the Changjiang (Yangtze) River in China includes hydrologically connected, subtropical wetlands with different hydrological characteristics. 2. We examined seed‐bank species composition and richness in marshes of two contrasting hydrological types: permanent marshes, fed by local runoff, and lakeshore marshes more closely connected to the regulated river. Lakeshore marshes are flooded annually to depth of approximately 1 m and during flooding they support an alternate, aquatic vegetation type. The soil seed bank in March was a comparative estimator of species diversity. At the beginning of the growing season it included seeds from both phases of alternating vegetation types associated with the annual hydrological cycle. 3. A regional pool of 101 species was detected in the seed banks of six wetlands associated with the river and its tributaries: 56 occurred in permanent marshes and 59 in lakeshore marshes, with only 15 common to both. Species rarefaction curves indicated that more species occurred in permanent than lakeshore marshes at equal numbers of individuals sampled. However, the more heterogeneous lakeshore seed banks were estimated (Chao 2) to have greater total species richness (81) than permanent marsh (60). 4. Analysis using Sørensen's coefficient of similarity and DCA ordination revealed complex variation, with much greater differences between hydrological types than within them, irrespective of geographical distance. The types also differed significantly in the composition of four functional groups of species. 5. Despite the potential for dispersal of propagules via the annually pulsing river system (hydrochory), at a regional and landscape scale, diversity is maintained largely by large‐scale temporal hydrological heterogeneity and smaller scale spatial and topographic heterogeneity.  相似文献   

18.
The “Outwelling Theory” states that salt marshes play a major role in exporting production to adjacent estuarine and coastal ecosystems. However, it has been found that some marshes act as net importers instead of net exporters of organic matter and nutrients. Once we include mangroves and refine the analysis to comprehend bacterioplankton, organic and stable isotope tracers, the picture became, more complex, making room for a revival of the outwelling idea. The exchanges between the Castro Marim salt marsh and the main estuary were tentatively established determining periodically, in a selected cross-section, the concentrations of TSS, FSS, VSS, NH4, NO2, NO3, NKjeldhal, SiO4, PO4, TDP, Chlorophyll a and Pheopigments, measuring their fluxes along tidal cycles and computing the corresponding budgets. Apparently, the sedimentary behaviour of the marsh will be close to equilibrium during the period of study. However, it will import mainly inert matter and export mainly organic matter in the same period. Moreover, extrapolating these results to the entire Guadiana salt marshes, the exchanges of sediment do not seem to be significant. Particularly, the marshes will not trap a significantly amount sediment transported by the main river (0.5%). It also seems to follow, that in a general way, the Guadiana salt marshes might have a more significant role than was anticipated in the system economy of OM and nutrients and their outwelling to coastal waters, assuring outputs that could amount to something like 6% of the river load of N, 1.2% of the river load of P, and 20-57% of the river load of TOC, for an average year, and 42% of the river load of N and 35% of the river load of P in a dry year. These findings suggest that a more detailed investigation, over an extended period of time, is certainly worthwhile.  相似文献   

19.
There is little published information about coastal salt marshes in south-western Australia, which are prominent in estuaries but absent from the high energy coastline. The zonation of the marshes of the Blackwood estuary resemble those in other parts of the world, in that Sarcocornia marsh occurs near the mouth, followed by rush marsh, with sedges further upstream, suggesting that salinity is a prime determining factor. Spartina and Phragmites are absent. The most exensive marsh is the Juncus kraussii rush community which is invaded by the paperbark tree, Melaleuca cuticularis. The sedge Baumea juncea forms a marsh community on the shores of the lower tidal river and a progression of species occurs with distance along the tidal river. A number of dynamic processes observed in these marshes are described and related to observations elsewhere  相似文献   

20.
Here, I examine the potential for dead plant material, or wrack, to act as a vector of dispersal for plants among coastal marshes along the Palmer River in New England, USA. Three hundred mats of wrack floating along a 2.5 km section of river spanning tidal fresh, brackish and salt marshes were sampled for propagules of plants from May 1997 to October 1998. Thirty species of plants and 2 species of algae were associated with the wrack, and 24 of the plant species were viable under greenhouse conditions. Common and abundant species of tidal fresh, brackish and salt marshes were found in the wrack, as well as introduced and invasive species. Wrack contained plants suited to different modes of dispersal, including water, wind and adherence to animals. Measurements of the movement of individual mats of wrack along a 200 m section of the river indicated that wrack travelled at speeds ranging from 1.1 to 2.6 km h−1, which translates to potential dispersal distances ranging from 6.5 to 15.9 km for one ebb or flood tide of 6 h duration. Tagged mats of wrack tracked for one ebb or flood tide travelled at least 2.5 km along the river. These results suggest that wrack may be an important agent of plant dispersal among coastal marshes in estuaries.  相似文献   

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