安徽省颍上县小张庄村畜牧业子系统能量与物质转化特征分析

本文分析了小张庄村1976—1987年畜牧业的发展特点,并着重分析了1987年该子系统的能量和物质的转化特征。指出目前小张庄村生态系统是稳定的,但效率低。要将其建设成为既稳定又高效的农业生态系统,必须从畜牧业子系统着手,提高饲料转化率。     

论建立农业经济生态系统良性物质循环及提高系统生产力的途径

如果从生态经济学的角度来看建立农业经济生态系统良性物质循环及提高系统生产力的问题,实质上就是如何同步提高农业经济生态系统中生产的经济效益和生态效益的问题。因为只有使这两种效益同步提高,人们在农业投入和耗费一定量劳动的过程中,才能既能实现农业经济生态系统能量的合理流动和物质的良性循环,保持系统的生态平衡;又能同时产出较高的农业经济产品量和商品量,满足人门日     

江苏省泰县河横村生态农业建设的研究 Ⅱ.江苏省泰县河横村农业生态系统功能的分析

本研究采用系统分析和灰色理论,从河横村农业生态系统的能量、物流和价值流出发,分析了河横村农业生态系统的功能特征。结果表明,由于生态农业的发展,河横村农业生态系统的功能已朝着良性循环的方向发展。总能量产投比已达2.5以上,土壤子系统中的营养物质也出现了盈额,N1.76kg/亩,P_2O_53.43kg/亩,K_2O0.53kg/亩;各个子系统的经济效益也得到了提高,种植业、副业和渔业收入的灰色模型发展指数分别为-0.043,-0.214和-0.251。根据复合关联度分析,提出了河横村农业生态系统良性循环的对策为:在强化和完善生态农业措施的基础上,特别要注意充分利用光热资源,增加农业投资,强化劳力素质,加强有机肥的开发和利用。     

国际能值研究热点和前沿的可视化分析

能值用以表征一种流动或储存的能量所包含另一类别能量的数量,即产品或者劳务形成过程中消耗的总能量,常以太阳能为度量标准。能值作为生态经济学中的新概念,它的提出实现了物质流、能量流、经济流、人口流和信息流等的统一量化,架设了“环境与经济间的桥梁”,能值理论和应用目前已成为生态经济学研究的热点领域,能值分析方法正日益发展成为生态经济系统评价的基本工具。文章首先以Web of Science数据库中1998─2013年间收录主题为“emergy”的文献为基础数据,对能值研究的学科、时间、区域和机构等分布情况进行了统计分析,发现能值研究文献数量呈逐年上升趋势,主要分布在生态、环境及能源相关学科,中、美、意大利3国及锡耶纳大学、北京师范大学、北京大学、中国科学院和佛罗里达大学等研究机构表现出较强的研究实力。其次,利用CiteSpace软件绘制了能值研究文献的共被引知识图谱,对其知识基础及核心作者的影响力进行了探讨。图谱研究显示,Odum H T、Brown M T、Hau J L、Ulgiati S等学者及其代表作品对能值理论知识基础的构建及相关研究的推进奠定了坚实的基础。最后,通过对能值研究领域出现关键词及膨胀词的共词分析与词频分析,绘制出能值领域的研究热点演进脉络,并探测环境可持续性、可持续发展、生态系统服务、电力生产、能值核算、生命周期研究法等前沿命题,可见系统可持续发展及能值与其它理论方法的结合应用将成为能值研究的新热点。目前能值研究文献数量持续增长,但其理论研究速度落后于应用范围及领域的延伸速度,能值转换率及评价指标体系已无法满足小区域、微观小系统的研究需求,核心作者及代表作品较少,且欠缺与动态模型及仿真技术的结合应用。因此,未来能值研究     

农业生态系统的能流结构及效率

农业生产可以看作是一个能量与物质的转化过程。人类的生产活动,是对于农业生态系统投入的一种补加能源。借以减少系统用于自我维持所消耗的能量,把更多的日光能转化为符合人类需要的产品。在传统的自给型农业中,这样补加能源主要采取劳畜力、有机肥等生物能源(或有机能源)的形式。在现代集约型农业中,补加能源则表现为投入化肥、机器、农药、电力、矿质燃料等化石能源形式。而且具有较高的增产效果。当前,增加化石能     

天津城市水系统分析及行为模拟

在复合生态系统中,水作为一种物质流,是联系社会、经济、自然三个子系统的纽带.本文以天津城市生态系统为例,参考灵敏度模型的理论与方法,分析水系统各因素间的相互作用方式,模拟系统行为,以探讨缓解天津用水矛盾,促进持续发展的对策.     

黑龙江省庆安县六合村生态农业建设与评价 Ⅱ.松嫩平原漫川漫岗农业系统能量流动和物质循环的分析

本文运用系统生态学的系统分析方法,从能量流动、物质循环方面,以黑龙江省庆安县六合村为典型,对我国东北松嫩平原漫川漫岗农业系统生态农业建设前后进行分析比较研究。分析结果表明,六合村的生态农业建设为松嫩平原农业生态系统的改善,经济水平较低地区的农业发展提供了有益的经验。通过合理调整系统内的能量流及物质环循,在提高系统生产力的同时,保护农业生态环境。     

广东省农业现代化科技示范区的能值分析与评价指标研究

为了从生态经济学角度揭示农业现代化示范区园区的生态经济运行质量,探索一条能更客观、更简单地评价农业科技园区的新途径,文章运用能值理论和方法,分析和评价了广东省农业现代化科技示范区的能值投资率、能值产出率、能值密度、人均能值用量、环境负载率、能值生产率、每万元产值消耗能值和基于能值分析的可持续发展指数等指标,并从中筛选出其能值评价的主要指标。主要结果如下,(1)从2000—2004年,广东省农业现代化科技示范区的总投入能值和总产出能值呈现快速增加的趋势,能值密度和环境负载率持续增加,人均能值使用量,能值投资率和能值生产率呈波动增加的趋势,而能值产出率,可持续发展指数和每万元产值消耗能值呈波动下降的趋势。这说明该示范区总体上呈现快速发展的趋势,经济实力和科技竞争力不断增加。(2)本研究运用主成分分析法、因子分析法和实证对比研究法提出评价农业现代化科技示范区的最佳指标是人均能值使用量和环境负载率。     

试论生态农业中物质能量的多层次利用

物质和能量的多层次利用是提高农业生态系统经济效益和生态效益的有效途径,构成生态农业研究的一个重要领域。本文从分析各农业产业间物质、能量的关系入手,探讨了多层次利用之所以能够提高物质、能量利用效率的原理,提出多层次利用的结构可分产业内和产业间两个层次,而后者是更加重要的,是实现多层次利用物质、能量的基础。文章没有具体罗列各种多层次利用的模式(这类文献已经发表了很多),而是总结了七条设计多层次利用的一般原则,它们是:因地制宜的原则;合理确定产业及农业生物种类数目的原则;突出重点产业的原则;合理控制辅助能量的原则;尽量扩大生产者种群的原则;合理安排空间布局的原则;加强防疫的原则。     

双台河口湿地生态系统物质生产服务价值评价去重复性计算研究

重复性计算在生态系统服务评价研究中是一个突出的问题,严重影响评价结果的准确性,如果不能正确地去除湿地生态系统服务价值评价中重复计算的部分,会使评价结果的可信度降低。文章在传统能值理论的能值转换率基础上,根据能值流程图,提出了能值转换系数的概念,对双台河口湿地生态系统物质生产服务价值进行了评价,以期找到合理的方法将评价过程中产生的重复性计算剔除,使得评价结果更加准确。通过对稳定系统中"分离(split)"、"反馈(feedback)"、"共产物(co-product)"3个基本机制的"预先分析"以看出,未经能值流程图预先分析的能值转换系数结果与经预先分析的结果相比,存在12%~38%的误差,预先分析后的结果更加准确。在此基础上,对双台河口湿地生态系统物质生产服务价值及重复性计算进行了评价。研究结果显示,双台河口湿地生态系统物质生产服务功能年能值价值为34.54×10~(19) sej·a~(-1),在评价过程中产生的重复性计算量为5.95×10~(19) sej·a~(-1),评价过程中重复性计算剔除率为15%,表明在对双台河口湿地物质生产服务进行价值评价时,产生的重复性计算问题不可忽视。通过对湿地生态系统服务流程图的描绘,可以有效剔除评价过程中产生的重复性计算,更加精确地量化湿地生态系统服务的价值。同时,该方法不仅适用于湿地生态系统,对其它生态系统服务价值的评价也有一定借鉴意义。     

Representation of the world's biophysical conditions by the global protected area network

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.     

Quantitative composition of the defensive secretion ofBledius species (Coleoptera: Staphylinidae: Oxytelinae) is adapted to naturally occurring predators

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.     

Democracy versus development: New urban debates

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.     

Achieving Open Access to Conservation Science

Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación     

A framework to measure the wildness of managed large vertebrate populations

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.     

Sexual Predators,Energy Development,and Conservation in Greater Yellowstone

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.     

Comparison of the insecticidal effects of water extracted and intact aromatic plants onAcanthoscelides obtectus,a bruchid beetle pest of kidney beans

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.     

Rapid,recurring, structured survey versus bioblitz for generating biodiversity data and analysis with a multispecies abundance model

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.     

Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters

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.     

Some polyphagous Homoptera gain protection from their natural enemies by feeding on the toxic plantsSpartium junceum andErythrina corallodendrum (Leguminosae)

Summary Interactions were studied among alkaloid-containing legumes (Erythrina corallodendrum andSpartium junceum) and non-toxic plants (Citrus sinensis, Cucurbita moschata andEuphorbia tirucalli), several polyphagous homopterans,Aphis craccivora (Aphididae),Icerya purchasi, I. aegyptiaca (Margarodidae),Lepidosaphes ulmi (Diaspididae) andPlanococcus citri (Pseudococcidae), and some major natural enemies of these homopterans. Significant reductions in survival due to negative effects of alkaloid containing as compared with non-alkaloidal plants were recorded for the predatorsRodolia cardinalis andChilocorus bipustulatus, but not forCryptolaemus montrouzieri (Coleoptera: Coccinellidae),Chrysoperla carnea (Neuroptera: Chrysopidae) andSympherobius sanctus (Neuroptera: Sympherobiidae). The development time of the larvae or pupae ofR. cardinalis, C. carnea andS. sanctus was longer on the toxic plants than on the non-toxic ones. The percentage of parasitism ofA. craccivora collected from the non-alkaloidal plantsVicia palaestina andMelilotus albus was much higher than that onS. junceum. The parasitoid complexes ofA. craccivora differed between both plant groups. The nutritive value of honeydew ofI. purchasi andA. craccivora, as expressed by the life span ofEncyrtus infelix (Hymenoptera: Encyrtidae) adults, was also investigated. Life spans were significantly longer when the wasps fed on honeydew produced on non-alkaloidal plants (C. sinensis andPittosporum tobira) than on alkaloid containing plants whenI. purchasi — but notA. craccivora — was the producer. It is suggested that the chemical defense ofE. corallodendrum andS. junceum is exploited by polyphagous phytophages to reduce predation. In nature, population growth and density of four of the investigated homopterans are conspicuously high when they developed on the alkaloid containing plant species, and very low on non-alkaloid plants. The efficiency of their natural enemies may be reduced by sequestration of alkaloids (or other toxic plant compounds) or their transfer into excreted honeydew. Therefore it is assumed that a generalist phytophagous homopteran may be protected from its natural enemies, although at different rates of efficiency, if it can safely sequester the host allelochemical when it develops on toxic species within its host range.