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1.
为研究生物复合剂对垃圾填埋场的除臭效果,对垃圾填埋作业面喷洒生物复合剂,检测生物复合剂对垃圾填埋作业面填埋中NH3和H2S的浓度变化的影响.对作业面填埋气中NH3、H2S浓度的检测,19∶00时的NH3浓度相对于7∶00时的NH3浓度降低了90%左右,19∶00时的H2S浓度相对于7∶00时的H2S浓度降低了95%以上.结果表明,生物复合剂对垃圾填埋作业面填埋气中的NH3和H2S具有良好的去除效果.  相似文献   

2.
外来植物在迁入地的生存和繁殖策略,是入侵生物学研究的热门话题之一。开展入侵植物的繁殖策略研究,有助于深入了解入侵生物在迁入地的生存繁衍机制,对入侵植物在可控范围内的适当使用具有重要的指导意义。通过野外传粉昆虫观测、光学和电镜扫描观测和人工控制授粉等方法,对外来植物大花老鸦嘴(Thunbergia grandiflora)在广州和深圳的4个居群的开花物候、花部结构、花粉活力、传粉昆虫及其行为等传粉生物学特征进行了研究。结果表明:大花老鸦嘴的单花花期为1 d,上午10:00时花粉活力最高,长雄蕊花粉活力可达73.92%,短雄蕊花粉活力可达71.54%,随后花粉活力逐渐下降。主要传粉者为扁柄木蜂(Xylocopa latipes),开花当天访花高峰期的9:00—10:00,单花访花频率可达5 h-1以上,之后开始逐渐减少,14:00之后未观测到扁柄木蜂访花,18:00后仅剩蚂蚁等体型较小的昆虫长期栖息于花序或花蕾。控制授粉实验结果显示,无论是人工异株授粉、自花授粉,还是自然授粉,结果率均为0,4个居群均未见结实。光学显微镜下子房发育完整;电镜扫描观测结果显示其花粉在柱头上能萌发,但花粉管不能延伸到子房位置。目前在园林栽培的大花老鸭嘴均以块根或茎为繁殖体培育苗木,虽然这些植株均能开出鲜艳的花朵,花粉传递者也充足,但未见任何结果现象。因此,初步推测本次研究区域内的大花老鸭嘴种群可能来自相同或相近的无性系,故不同居群间异株授粉的不结果现象可能为“自交不亲和”,或“染色体多倍化”所致。  相似文献   

3.
植物的开花及传粉策略是植物有性繁殖成功与否的关键,影响其种群的延续及发展.对湿地植物大花百合(Lilium concolor var. megalanthum)的两种不同性别表型植株进行开花策略及访花昆虫传粉行为差异的研究,比较两种性别表型的大花百合开花动态,并通过观察昆虫对植株的访花行为,探讨其访花行为生态位的差异.结果显示:在开花当天,大花百合两性植株开花时间比雄性植株晚约2 h,同时两性植株散粉时间较雄性植株晚2-3 h;研究期间观察到的大花百合的访花者有7种,其中中华蜜蜂(Apis cerana)与蓝灰蝶(Everes argiades)为大花百合两种性别表型植株的主要传粉者.中华蜜蜂主要采集花粉,蓝灰蝶主要吸取花蜜;中华蜜蜂与蓝灰蝶在空间及时间尺度上存在互补式的传粉行为.空间上,二者对大花百合花部访问的位置相互错开;时间上,中华蜜蜂对雄性植株的访花时间为双峰状,蓝灰蝶的访花高峰期则多集中于下午;蓝灰蝶对两性植株的单株访花时间显著高于中华蜜蜂(P=0.007 <0.05).本研究表明当两性植株可接受访花时,访花昆虫多已访问过雄性植株,增加了种群中异花授粉的概率,并促进种群...  相似文献   

4.
据对有较详细分布资料的206种祝蛾科昆虫分析,中国祝蛾科昆虫其区系组成以广布种占多数,共计62种,占30.1%,东洋界55种,占26.7%.在中国动物地理区划中,华中、华南、西南三区分布的种占所采总数的60.4%,可见此三区关系较为密切.表3,参6.  相似文献   

5.
吴东辉  张柏  陈鹏 《生态环境》2006,15(4):802-806
对长春市郊区天然次生林、市内公园风景林、郊区防护林和农田等土地利用生境进行土壤昆虫幼虫调查,研究土地利用差异对土壤昆虫幼虫群落特征的影响。研究区共捕获土壤昆虫幼虫35科411只,其中鞘翅目幼虫14科319只,双翅目幼虫13科64只,鳞翅目幼虫8科28只。研究结果表明:不同土地利用生境土壤昆虫幼虫群落组成与生态分布存在差异,防护林和农田土壤昆虫幼虫的类群数和个体密度显著减少;除农田外,其他生境土壤昆虫幼虫群落个体密度和类群数主要集中分布在0~5cm土壤层,生境凋落物的移除对土壤昆虫幼虫群落组成影响不明显;此外,鞘翅目、双翅目和鳞翅目幼虫对土地利用和植被类型变化的响应也不同。  相似文献   

6.
美洲商陆(Phytolacca americana)是一种我国广泛分布的商陆科入侵植物。通过实验观察和人工控制套袋等方法,对其开花动态、花部综合特征、繁育系统和种子萌发率等与繁殖相关的特性进行了研究,探讨了这些繁殖特性与入侵性的关系。结果表明,美洲商陆每年6—8月开花,单花序的花期为6~7 d,单花的花期为2~4 d。其花直径、雄蕊长、花柱长、柱头直径分别为(6.43±0.15)、(2.83±0.10)、(0.92±0.06)和(1.02±0.08) mm。套袋实验表明,美洲商陆自交亲和,自交结实率较高,为(93.33±1.92)%,而其同样存在异交结实现象,开花前去雄,不套袋,自然条件下其结实率为(42.22±2.22)%,其 P/O 值为372.37±31.24,杂交指数为3。综合套袋实验、P/O 值及杂交指数,表明其繁育系统为兼性自交,有时需要传粉者。主要访花昆虫为蜜蜂科(Apidae)、胡蜂科(Vespidae)、麻蝇科(Sarcophagidae)和食蚜蝇科(Syrphidae)昆虫。种子千粒质量为6.43 g,室内萌发率相对较低,但出苗整齐,寿命长。交配机制灵活、结实量大、种子寿命长、具有克隆繁殖等特性增强了美洲商陆的入侵性,是其入侵成功的重要因素。  相似文献   

7.
利用基于光腔衰荡光谱(CRDS)测量技术,于2009年1月至2011年12月在龙凤山区域大气本底站对大气中CO2进行了在线观测.龙凤山CO2浓度日最低值出现在13∶00—16∶00,此时植被光合作用对CO2的吸收作用以及大气垂直运动导致的稀释作用最强.春、秋和冬季CO2浓度日最高值出现在7∶00—9∶00,夏季日最高值出现在3∶00.夏季日高值出现的早,是由于夏季日出时间较早,植物在5∶00左右就开始有光合作用,此时CO2浓度开始降低.一年中CO2月平均浓度低值出现在6—9月,高值出现在12月和1月,并在5月和10月分别出现1个次高值.CO2次高值是由于当地农村春季和秋季焚烧秸秆造成的.CO2年均值浓度从2009年的711±23 mg·L-1上升到2011年的723±25 mg·L-1,年平均增长率为0.89%.在夏季、冬季,当风向来自EESE-SE-SSE方位时CO2浓度较高,而当风向来自W-WNW-NW方位时CO2浓度较低.龙凤山区域大气本底站周边森林在夏季对CO2有很强的吸收,占夏季浓度的8.5%.  相似文献   

8.
长白山红松阔叶林不同恢复阶段蛾类组成和多样性研究   总被引:4,自引:0,他引:4  
研究了长白山地区不同恢复阶段的红松阔叶林内蛾类的物种组成和多样性,分析了蛾类科属组成与林分不同恢复阶段间的关系.结果表明,2006~2007年调查蛾类23科,410种,共计6520头.红松阔叶林Ⅱ(MF)内物种多度以及Fisher'a和eH最高,4个林分内蛾类种-多度关系均趋于对数级数分布,符合生态位优先占领假说.单因素ANOVA分析表明,苔蛾科(Lithosiidae)、夜蛾科(Noctuidae)、螟蛾科(Pyralidae)、灯蛾科(Arctiidae)和卷蛾科(Tortricidae)蛾类物种数与林分干扰恢复程度显著相关,尺蛾科(Geometridae)、刺蛾科(Limacodidae)、天蛾科(Sphingidae)、舟蛾科(Notodontidae)蛾类头数与林分恢复阶段相关不显著.  相似文献   

9.
对上海居住区常见的23种植物群落的降温增湿效应进行观测的结果表明,所有植物群落都有降温增湿作用,且群落间降温增湿效应差异较大.各群落的降温增湿效应在13∶ 00-14∶ 00最强,与草坪之间的差异达到最大;在16∶ 00-17∶ 00,各群落间降温增湿效应差异小,18%的植物群落降温效应低于草坪,45%的植物群落增湿效应低于草坪.针叶林、针阔混交林和竹林的降温增湿效应最强,日均降温效应>2.3 ℃,日均增湿效应>12.4%.  相似文献   

10.
使用宽范围粒径谱仪(WPS)对嘉兴市2015年5月1—31日10 nm—10μm的气溶胶粒径分布进行了测定,结合HYSPLIT轨迹模式的气团聚类分型结果,分析了不同类型气团下气溶胶数浓度和表面积浓度的日变化和粒径分布特征.结果表明,观测期间嘉兴市主要受5类气团控制,分别为海洋性气团(Type1,31%)、局地气团(Type2,32%)、西南内陆气团(Type3,25%)、海陆混合气团(Type4,8%)以及西北内陆气团(Type5,4%).气团类型对核模态(10—20 nm)和粗模态(1.0—10μm)粒子数浓度日变化的影响较大,其次是积聚模态(100—1000 nm)粒子,对爱根核模态(20—100 nm)粒子数浓度日变化的影响较小.不同类型气团下气溶胶数浓度谱分布均为单峰型分布,但是谱分布特征差异较大.不同类型气团下表面积浓度的日变化多为双峰型分布,峰值出现在07∶00—09∶00和17∶00—21∶00;气溶胶表面积浓度谱均为三峰型分布,峰值分别位于120—150 nm、500—700 nm和1.2—1.5μm,Type5气团下的表面积峰值浓度最小,Type3气团下的表面积峰值浓度最大.  相似文献   

11.
A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.  相似文献   

12.
Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.  相似文献   

13.
Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.  相似文献   

14.
Summary The adaptation of defensive secretions to their target organisms was examined for the abdominal gland secretions ofBledius furcatus, B. spectabilis andB. arenarius. Therefore the target organisms of the secretion of theseBledius species (i.e. their predators) had to be identified. At the collection sites examined these were the earwigLabidura riparia, the antCataglyphis bicolor, the flyLispe candicans, different carabids of the generaPogonus, Dichirotrichus, Dyschirius, Bembidion andCalathus and the wading birdsHaematopus ostralegus andCalidris alba. The secretion of the abdominal glands contains the toxin ptoluquinone dissolved in either-dodecalactone and 1-undecene (B. furcatus andB. spectabilis) or in octanoic acid and octyloctanoate (B. arenarius). The ratio of these solvents is species-specific. Application experiments using some of the natural insect predators (L. riparia, C. bicolor, Pogonus, Di. gustavii, Dyschirius) revealed that these solvent ratios provided a more effective deterrent than other possible ratios. Thus by combining the solvents in certain ratios, the capability of cuticular penetration and therefore the effectiveness of the defensive secretions are adapted to their natural targets.  相似文献   

15.
The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest.  相似文献   

16.
An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.  相似文献   

17.
As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.  相似文献   

18.
Abstract: In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies—recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)—differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in‐migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.  相似文献   

19.
Large, intact areas of tropical peatland are highly threatened at a global scale by the expansion of commercial agriculture and other forms of economic development. Conserving peatlands on a landscape scale, with their hydrology intact, is of international conservation importance to preserve their distinctive biodiversity and ecosystem services and maintain their resilience to future environmental change. We explored threats to and opportunities for conserving remaining intact tropical peatlands; thus, we excluded peatlands of Indonesia and Malaysia, where extensive deforestation, drainage, and conversion to plantations means conservation in this region can protect only small fragments of the original ecosystem. We focused on a case study, the Pastaza‐Marañón Foreland Basin (PMFB) in Peru, which is among the largest known intact tropical peatland landscapes in the world and is representative of peatland vulnerability. Maintenance of the hydrological conditions critical for carbon storage and ecosystem function of peatlands is, in the PMFB, primarily threatened by expansion of commercial agriculture linked to new transport infrastructure that is facilitating access to remote areas. There remain opportunities in the PMFB and elsewhere to develop alternative, more sustainable land‐use practices. Although some of the peatlands in the PMFB fall within existing legally protected areas, this protection does not include the most carbon‐dense (domed pole forest) areas. New carbon‐based conservation instruments (e.g., REDD+, Green Climate Fund), developing markets for sustainable peatland products, transferring land title to local communities, and expanding protected areas offer pathways to increased protection for intact tropical peatlands in Amazonia and elsewhere, such as those in New Guinea and Central Africa which remain, for the moment, broadly beyond the frontier of commercial development.  相似文献   

20.
Summary Acanthoscelides obtectus (Say) is one of the most damaging pests of kidney beans,Phaseolus vulgaris L. worldwide. However, aromatic plants from the families Lamiaceae, Lauraceae, Myrtaceae and Poaceae can protect kidney beans by direct or delayed insecticidal effect, through increased adult mortality and inhibition of beetle reproduction (both oviposition and adult emergence). The efficiency of hydrodistillated and intact plants fromThymus vulgaris andT. serpyllum, Mentha piperata, Rosmarinus officinalis, Satureia hortensis, Eucalyptus globulus, Laurus nobilis, Origanum vulgare, andCymbopogon nardus was compared. For both extracts,Origanum vulgare had the best effect. The insecticidal effect was induced by more than the essential oils because no significant difference was noticed between distilled and intact plants extract. Inhibition of reproduction was particularly important. These results suggest that lipidic as well as non lipidic, allelochemicals, such as phenolics, or non-protein amino-acids, or flavonoids may be involved in the toxicity of aromatic plants to this beetle.  相似文献   

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