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1.
基于集对分析的矿区生态承载力定量评价   总被引:6,自引:2,他引:4  
据矿区复合生态系统特点,采用主成分分析法和独立性分析法筛选指标,建立矿区生态承载力评价指标体系,并合理确定了评价等级标准。以民勤县红沙岗矿区为例,采用集对分析法进行矿区生态承载力评价,由平均联系度最大隶属原则确定生态承载力所处的级别。应用结果表明:由于红沙岗矿区所处区域环境背景特点和煤矿开采引起的一系列生态问题,生态承载力处于弱稳定、中等承载、较高压状态。通过对评价结果分析,指出了提高矿区生态承载力的发展对策,可供相关部门进行矿区生态恢复和制定适宜的发展战略借鉴和参考。  相似文献   

2.
新疆水资源生态足迹核算与预测   总被引:4,自引:0,他引:4       下载免费PDF全文
根据水资源生态足迹的基本原理和计算模型,引入水资源负载指数,对新疆2005—2014年水资源生态足迹、水资源生态承载力进行计算,并运用灰色预测模型GM(1,1)对2015—2025年的生态赤字/盈余趋势进行预测。结果表明:(1)新疆历年水资源生态足迹大于水资源承载力,处于生态赤字状态,从2005年的-7.83×10~7hm~2下降至2013年的-9.06×10~7hm~2,水资源开发率很低;(2)2005—2014年新疆水资源生态足迹和承载力均呈上升趋势,人均生态足迹和人均承载力呈上下波动状态,生产用水生态足迹在三个水资源账户中比例最大,远远超出其它两部分,占总水资源足迹的95.86%;(3)水资源负载指数总体呈上升趋势,表明水资源的利用程度逐渐加强,2005—2012年负载指数在2~5之间,表明新疆水资源利用程度中等;2013—2014年负载指数在5~10之间,表明新疆水资源利用程度高,开发条件困难;(4)新疆水资源存在分布不均匀的状态,南疆、北疆、东疆差异较大,南疆、北疆水资源生态足迹、水资源承载力均大于东疆,而南、北疆万元GDP水资源生态足迹则小于东疆;(5)对2015—2025年水资源进行预测,新疆水资源一直处于生态赤字状态,而且水资源生态赤字呈逐年减小的趋势,水资源生态赤字越来越严重,今后的形势越来越严峻,在利用中提高节水意识。  相似文献   

3.
辽宁省生态承载力空间分异及其影响因素分析   总被引:1,自引:0,他引:1  
在阐述区域生态系统承载机制的基础上,构建了区域生态承载力评价指标体系,运用状态空间法研究了辽宁省地市尺度的生态承载力空间分异。结果表明:辽宁省可分为四个生态承载状况类型区:适度可载区、轻度超载区、中度超载区和重超载区,生态承载状况在整体上呈现沿海和内陆的分异;地市间生态潜力的差异是生态承载状况分异的主要驱动因素;环境治理水平、经济发展质量和人口压力是分异的主要影响因素。  相似文献   

4.
新疆额尔齐斯河流域生态承载力研究   总被引:1,自引:0,他引:1  
通过构建额尔齐斯河流域生态承载力评价指标体系,对各评价指标建立隶属模型,对指标进行正规化处理以消除量纲影响,并利用AHP法求得各指标权重值,利用生态承载力综合评价方法,对额尔齐斯河流域的系统弹性度、资源承载指数和资源承载压力度进行分级评价,最后对额尔齐斯河流域生态承载力进行了综合评价,并提出了建议。  相似文献   

5.
水土资源的数量与质量对农业可持续发展具有重要意义。选取22个指标建立了哈萨克斯坦农业水土资源承载力评价体系,将层次分析法、熵权法与模糊综合评价模型相结合,分析了哈萨克斯坦2001-2017年农业水土资源承载力的动态变化及区域差异,用障碍度法定量识别其影响因素。结果表明:①2001-2017年,哈萨克斯坦农业水土资源承载力整体呈波动缓慢上升趋势,水土资源子系统和经济子系统的评价指数缓慢上升,生态子系统和社会子系统评价指数明显下降。②农业水土资源承载力在地区间差异显著,高承载力区主要集中在北部、中部和东部地区,低承载力区在南部和西部地区。北哈萨克斯坦州、科斯塔奈州和阿克莫拉州的承载力高,呈逐年增大趋势,阿特劳州和南哈萨克斯坦州的承载力较低,且呈减小趋势。③承载力在2001-2009年主要受垦殖率、单位耕地面积农业产值及农业灌溉率的影响,在2010-2017年主要受农业水土资源匹配系数、人口密度及单位土地污水负荷的影响,生态环境因素逐渐成为承载力障碍因子。  相似文献   

6.
水土资源的数量与质量对农业可持续发展具有重要意义。选取22个指标建立了哈萨克斯坦农业水土资源承载力评价体系,将层次分析法、熵权法与模糊综合评价模型相结合,分析了哈萨克斯坦2001—2017年农业水土资源承载力的动态变化及区域差异,用障碍度法定量识别其影响因素。结果表明:① 2001—2017年,哈萨克斯坦农业水土资源承载力整体呈波动缓慢上升趋势,水土资源子系统和经济子系统的评价指数缓慢上升,生态子系统和社会子系统评价指数明显下降。② 农业水土资源承载力在地区间差异显著,高承载力区主要集中在北部、中部和东部地区,低承载力区在南部和西部地区。北哈萨克斯坦州、科斯塔奈州和阿克莫拉州的承载力高,呈逐年增大趋势,阿特劳州和南哈萨克斯坦州的承载力较低,且呈减小趋势。③ 承载力在2001—2009年主要受垦殖率、单位耕地面积农业产值及农业灌溉率的影响,在2010—2017年主要受农业水土资源匹配系数、人口密度及单位土地污水负荷的影响,生态环境因素逐渐成为承载力障碍因子。  相似文献   

7.
甘肃省1990—2002年生态足迹的计算与分析   总被引:9,自引:2,他引:9  
本文运用生态足迹模型对甘肃省1990—2002年的生态足迹进行了计算和分析。结果表明,1990—2002年间甘肃省的人均生态足迹和总生态足迹需求均呈逐渐增长趋势,而人均生态承载力和总的生态承载力均有不同程度的下降。运用万元GDP、人均贸易足迹和生态协调性系数指标对计算结果进行分析,得出甘肃省的发展是通过消耗自然资本存量来弥补生态承载力的不足的,处于一种生态不协调状态。  相似文献   

8.
本文运用生态足迹模型对甘孜州2004年的生态足迹进行了计算和分析,结果表明:甘孜州人均生态足迹为2.33hm2,人均生态承载力为1.95hm2,生态赤字为0.38hm2,自然资源消耗已经超过生态系统的承载力,其发展模式处于不可持续状态,进一步分析了存在生产性生态赤字的原因和减缓生态赤字的途径和方法。  相似文献   

9.
西北旱区生态服务价值时空动态研究   总被引:1,自引:0,他引:1       下载免费PDF全文
为探明西北旱区生态服务价值的时空差异性,以2004—2012年相关数据为基础,对其生态服务价值进行计算。结果表明:(1)2012年西北旱区的生态服务价值较2004年增加了166.1×109元,而人均生态服务价值却减少了8元,说明人口的增速比生态服务价值的增速大,应适当控制人口增长;(2)西北旱区各省区生态服务价值变化大小依次为甘肃陕西中北部新疆内蒙古中西部青海宁夏,其中宁夏和青海为负变化;(3)2004—2012年间西北旱区生态经济协调度为0.33,表明生态环境和经济发展处于轻度协调状态;(4)敏感性指数小于1,说明西北旱区生态服务价值对生态价值系数弹性较弱,本文研究结果真实可信。研究期内的土地利用变化取得了较明显的生态效益,为西北旱区的经济建设和社会发展提供了良好的环境平台。  相似文献   

10.
甘肃省相对资源承载力的动态变化与区域差异研究   总被引:1,自引:0,他引:1  
采用相对资源承载力的方法,分析了甘肃省及各地区2001-2008年相对自然资源承载力、相对经济资源承载力和综合承载力及其变化过程。结果表明:甘肃省的承载状态自2003年以后处于富余状态,自然资源成为甘肃省主要承载资源;甘肃省超载最严重的是临夏,其次是陇南,然后依次是天水、甘南、定西、武威。省会兰州、嘉峪关、金昌、白银、...  相似文献   

11.
Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.  相似文献   

12.
Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.  相似文献   

13.
The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   

14.
Plant Viruses Transmitted by Whiteflies   总被引:18,自引:0,他引:18  
One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.  相似文献   

15.
We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.  相似文献   

16.
Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.  相似文献   

17.
《干旱区科学》2014,(6):782-782
正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad  相似文献   

18.
A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVYN strain and six to the PVYO strain. No PVYC was found. Two other isolates reacted serologically like PVYO, but were unable to elicit a hypersensitive response from the Nytbr gene and probably represent the PVYZ group. At the molecular level, these two isolates showed a combination of both PVYO and PVYN and could be recombinants of these strains. Another isolate reacted serologically like PVYO, but induced vein necrosis in tobacco, like PVYN-Wilga. Some PVYN isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVYNTN group. The PVYNTN, PVYN-Wilga and PVYZ groups probably represent pathotypes within strains PVYN and PVYO, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.  相似文献   

19.
The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.  相似文献   

20.
Zusammenfassung Verbände des ökologischen Landbaus wie z. B. Bioland, Gäa, Demeter; Naturland, Ernte für das Leben oder Bio Suisse beschränken ihre Mitglieder bei der Wahl von Vorratsschutzmaßnahmen. Vorrang besitzen Maßnahmen zur Vermeidung von Schädlingen gegenüber Bekämpfungsmaßnahmen. Fallen müssen zur Befallsüberwachung eingesetzt werden, um einen Befall durch Vorratsschädlinge frühzeitig zu erkennen. Diese Maßnahmen sollen den weitgehenden Verzicht auf chemisch-synthetische Mittel ermöglichen. In diesem Beitrag werden die Empfehlungen der Verbände mit den derzeit verfügbaren chemischen Mitteln für den Vorratsschutz abgeglichen. Erfahrung in der praktischen Umsetzung von physikalischen und biologischen Verfahren werden diskutiert und Defizite bei der Befallsüberwachung und Bekämpfung beschrieben.  相似文献   

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