海南省农业能值分析

应用ＯｄｕｍＨＴ创立的能值分析理论和方法,对海南省农业进行了分析和评价,结果表明：由于自然条件得天独厚,环境资源对农业的贡献很大,环境资源能值占能值利用率的３０％,高于全国平均值（１３％）;净能值产出率为１．２７,高于日本和意大利,可以作为一种能值来源;农牧渔业产品的宏观经济价值远大于市场价值,农业生产中有相当大一部分环境资源无偿投入;环境承载指标为２．４４,远低于日本和意大利,环境压力较小,发展潜力很大。进而提出促进农业持续发展的有关建议与设想。     

农业科技发展态势与面向2020年的战略选择

1.至2020年农业领域科技发展新趋势新特点。世界农业科技发展新趋势将体现在如下5个方面：（1）植物种质资源与现代育种科技,如大规模植物种质资源发掘,光合作用研究的突破将加快现代育种大变革速度,系统生物学将为大规模基因资源发掘和利用提供系统的理论与技术基础,分子设计育种将产生突破性品种并催生智能品种诞生,第二代生物质原料生产将成为大农业的重要组成部分;（2）动物种质资源与现代育种科技,如大规模动物种质资源发掘,传统育种和基因工程相结合培育新品系是动物遗传育种发展方向,动物克隆技术和转基因动物将进一步取得突破,良种化和健康养殖科技发展迅速;（3）源节约型农业科技,如耕地资源集约利用与耕地质量定向培育科技发展,农田生态系统节水技术体系和建设流域水资源保障体系,高效新肥料研制和集成农田生态系统养分技术,低碳农业技术将成为未来的重要技术;（4）农业生产与食品安全科技,如支撑食品安全的生产技术发展迅速,更加关注营养保健功能食品的科技和食品安全监控技术,危险性快速评估技术体系技术得到广泛应用;（5）农业信息化和精准农业科技,如农业信息服务网络化科技和种养业管理信息化科技将加速发展,精准农业科技进入新的发展阶段,农业装备制造技术向大型和复式作业等方向发展。2.中国农业发展和粮食安全面临的挑战和对科技的重大需求。（1）农业发展面临新的挑战。在生产上,小规模经营与大市场和现代化的矛盾更加突出;耕地刚性下降和水资源短缺对农业形成的威胁越来越严峻;科技体系不能适应市场发展和农民对技术的需求;许多农业资源的利用和管理与农业食物系统的可持续性相悖。在市场上,对食品质量和安全将提出更高要求;整个农产品供应链系统正经历着历史性变化;贸易自由化使农产品进口压力进一步加大。（2）国家粮食安全面临的挑战：我国粮食安全于2008年已经突破了95%自给率目标,2010年更下降到90.6%;我们预测,我国粮食需求在2020年将达到6.7亿t,在现有政策下需求增长将高于生产增长,粮食自给率到2020年将下降到87%左右。（3）农业科技创新是发展农业和保障国家粮食安全的重大需求：面对农业发展和粮食安全的挑战,我国急需在植物种质资源利用与现代育种、动物种质资源利用与现代育种、资源节约型农业、农业生产与食品安全、农业信息化和精准农业等五大科技领域实现突破。为此,国家最近对农业科技发展提出了新的要求,特别是构建＂生态高值农业＂技术体系。中国科学院的优势在于多学科联合,能够在科技综合研究和集成基础上实现重大突破。如果把以上五大科技领域联合起来,在＂生态高值农业＂科技发展上将能起到国家科技发展的引领作用。3.面向2020的农业科技战略选择：构建我国生态高值农业产业体系。生态高值农业含义：所谓＂生态＂,就是要体现农业既能为社会提供安全、优质的农产品,又能实现农业资源的永续利用;所谓＂高值＂,就是要体现农业有很高的土地产出率、投入产出率、劳动生产率。因此,＂生态高值农业＂是集约化经营与生态化生产有机结合的现代农业。它以健康消费需求为导向,以提高农业市场竞争力和可持续发展能力为核心,是转变农业增长方式、提高农业综合生产能力的集中体现。生态高值农业科技的发展目标：到2020年,通过重点农业科技领域的重大创新突破,为不断满足日益增长的农产品总量、质量、安全和多功能的需求以及改善农业生产结构、生态环境和农业资源永续利用等生态高值农业体系提供科技支撑。生态高值农业研发内容：（1）提升＂中国至2050年农业科技发展路线图＂的理念与五大科技领域的研究水平;（2）建立生态高值农业的综合技术体系;（3）研发六大城市圈（如北京、上海、重庆、武汉、沈阳、南京等）、十大典型区域生态高值农业发展模式及其技术支撑体系（长三角城市群郊区生态高值农业模式,华中种养加一体化农业圈层模式,西南山地立体农业生态高值农业模式,南方亚热带特种农林果综合开发模式,滨海滩涂农业综合开发利用模式,黄土高原水土保持及农林果流域开发模式,黄淮海平原粮养加农业综合模式,东北平原粮食基地综合开发利用模式,西北寒旱区农牧综合开发模式,北部漠境盐湖综合整理开发模式）;（4）建设农产品产业化、加工产业化和综合产业化三大体系。最后在上述4个层次研发基础上,全面建立我国生态高值农业产业化网络体系。我国生态高值农业技术体系的构建：根据我国的现状,目前应主要从以下几个方面进行技术创新,（1）无公害农产品种养殖技术;（2）农产品加工技术;（3）我国传统农业精华技术;（4）标准化生产技术;（5）高新农业技术。对中国科学院提出的建议：（1）将＂生态高值农业＂列为中国科学院＂十二五＂的重大研发项目;（2）组织＂农业领域战略研究组＂和中国科学院有关单位提出生态高值农业建设的项目规划,并通过院部将此项目向国家有关部委推荐;（3）组织全院农业科研力量,联合全国的有关力量,首先在城市郊区农业与经济相对发达的地区,建立我国＂生态高值农业＂模式及其配套技术体系。     

长三角地区农田化肥投入快速增长的经济学诱因分析

农田化肥大量投入是引起农业面源污染的重要原因.根据长三角地区1980-2005年种植业生产以及农产品市场的统计数据,从投入要素机会成本变化和农产品价格变化角度,探讨长三角地区农业生产中化肥投入快速增长的经济学诱因.研究结果表明,长三角地区土地密集型作物上化肥投入快速增长是由于土地机会成本增长远远高于化肥价格增长而产生的化肥对土地的替代;相对劳动密集型作物上化肥投入快速增长是由于劳动机会成本高速增长引发的化肥对劳动的替代,并且相对劳动密集型农产品市场价格波动对化肥投入量的影响也较为显著.     

湖南省农地利用碳排放与农业经济关系研究

基于化肥、农药、农膜、灌溉、翻耕和柴油6类农地利用碳排放源,测算了1999—2014年湖南省农地利用碳排放量和碳排放强度。在此基础上,分析得出1999—2014年湖南省农地利用碳排放与农业经济间的脱钩弹性关系,进一步利用环境库兹涅茨(environmental Kuznets curve,EKC)模型对农地利用碳排放与农业经济关系进行验证。结果表明:(1) 1999—2014年,湖南省农地利用碳排放与农业经济的脱钩关系表现为扩张负脱钩、弱脱钩和弱负脱钩3种状态,农地利用碳排放与农业经济的脱钩弹性指数变化呈现"快速增长—快速下降—平稳增长"的阶段性演进特征;(2)湖南省农地利用碳排放与农业经济的关系呈对数函数曲线,农地利用碳排放量、碳排放强度均随着农业经济增长而连续增长,在研究期内未出现下降拐点;(3)湖南省现阶段农业经济增长方式仍然以粗放型为主,存在着农业生产要素投入未能充分有效利用、农业生产对环境影响较大的问题。     

至2050年中国生态高值农业体系建设特征与目标

2010年6月7日,国家主席胡锦涛在两院（中国科学院、中国工程院）院士大会上针对农业科技明确指出：构建我国生态高值农业和生物产业体系,建成农业高值转化的产业体系。本文对＂生态高值农业＂进行论述。所谓生态,就是要体现农业既能为社会提供安全优质的农产品又能实现农业资源的永续利用,将农业纳入可持续发展的道路;所谓高值,就是要体现农业有很高的土地产出率、投入产出率、劳动生产率。因此,＂生态高值农业＂是集约化经营与生态化生产有机结合的现代农业。它以健康消费需求为导向,以提高农业市场竞争力和可持续发展能力为核心,兼有高投入、高产出、高效益与可持续发展的双重特性,是转变农业增长方式、提高农业综合生产能力的集中体现。     

河北省县域农业绿色全要素生产率的空间特征

农业绿色全要素生产率的提升是生态文明建设的关键。以河北省142个县域作为研究对象,运用非径向非角度、基于松弛的(slacks-based measures,SBM)方向性距离函数和全局参比曼奎斯特卢恩伯格(global MalmquistLuenberger,GML)生产率指数测算2000—2016年河北省县域农业绿色全要素生产率,并采用空间自相关方法分析河北省县域农业绿色全要素生产率的全局和局部空间特征。结果表明:(1)2000—2016年河北省县域农业绿色全要素生产率年均增长5. 42%,主要依靠绿色前沿技术进步驱动,如考虑环境因素,或可实现农业"波特‘双赢’假说";(2)从地区分布来看,河北省县域农业绿色全要素生产率增长存在地区不平衡的现象,其中冀北地区增长水平高于全省平均水平,而冀中与冀南地区增长水平落后于全省平均水平;(3)河北省县域农业绿色全要素生产率增长存在显著空间相关性,但空间相关性呈减弱趋势;(4)河北省县域农业绿色全要素生产率增长呈明显地理集聚特征,热点区向冀中、冀东南地区扩张,冷点区由冀北"一翼"向冀北"两翼"转移。     

基于GIS和能值分析的黑龙江省农业生态经济格局综合评价

采用能值分析方法和GIS空间分析技术,基于黑龙江省77个县(市、区)的社会经济统计数据,从时空动态视角评价了黑龙江省域及各县域的农业生态经济格局及其综合发展水平。结果表明,1996—2012年间,黑龙江省农业生态经济系统的能值投入与产出均呈明显的增长趋势,林产品产出能值增长幅度较大。1996—2012年研究区的环境承受压力增大,环境负载率由6.61增加到10.21,净能值产出率由5.37减少到4.79,可持续发展指数由7.47下降到5.43,说明该系统的可持续发展性能正在逐年弱化。在空间格局上,黑龙江省南部地区经济发展水平显著优于北部地区,但其农业生态环境水平和系统可持续能力低于北部地区。为了增加黑龙江省农业生态系统的可持续发展能力,未来需进一步调整农业结构,优化资源配置的投入,提高资源利用效率,降低环境负载率,使农业生态经济系统逐渐步入健康可持续发展轨道。     

基于投入视角的黄淮海平原农业碳排放与经济发展脱钩研究

农业增长对资源依赖的变化趋势以及农业发展与环境的互动关系日益引起学术界的关注.运用脱钩理论,以2000-2005和2005-2010年为时间尺度,以县域为空间尺度,探讨黄淮海平原农业碳排放与经济增长之间的脱钩关系,揭示两者脱钩发展的时间和空间演变趋势及转移特征,并尝试分析脱钩的内在机理.结果表明:(1)脱钩类型的数量结构和空间格局均发生明显变化,黄淮海平原农业正处于由资源依赖向技术依赖的过渡时期.2000-2005年农业碳排放与经济增长以强复钩和扩张性复钩为主,脱钩空间格局较为分散;2005-2010年以强脱钩和弱脱钩为主,脱钩区域呈现空间集聚态势;若考虑因技术进步带来的碳排放系数变化因素,脱钩趋势将会更加明显.造成这种空间格局的原因主要是经济增长与环境的关系较为复杂,经济发展、技术进步和制度创新等因素通过互动机制共同作用于农业生产经营主体.(2)脱钩类型的转换呈跳跃性,转换方式以强复钩、扩张性复钩转换为强脱钩、弱脱钩为主,且脱钩状态不稳定,持续脱钩难度较大.脱钩状况受到经济效应、技术效应和政策效应等因素的共同作用,3者作用的两面性是持续脱钩难的重要原因.     

依靠科技进步 发展低碳农业

在全球携手应对气候变暖、减少温室气体排放的背景下,发展低碳经济是解决气候变化与经济发展矛盾的有效途径。通过描述气候变化、固碳减排对粮食安全、土壤碳汇、森林固碳、资源循环利用等影响和促进作用,深入分析发展低碳经济与可持续发展的关系,探讨如何在农业领域内开发高效循环生产体系,从而实现农业生产过程的固碳减排目的。由此,提出发展低碳农业是实现低碳经济的目标之一,它是一个复合技术体系,涉及了绿色农业、循环农业、生态文明、可持续发展理念。必须通过科学技术的突破,改造、提升低碳农业技术,改变农业现有的＂高能耗、高污染＂的生产状况,实现低碳生产、生活方式的转变。最后提出发展现代的低碳农业产业经济的对策和思考。     

海南省农业能值分析

应用ＯｄｕｍＨＴ创立的能值分析理论和方法,对海南省农业进行了分析和评价,结果表明：由于自然条件得天独厚,环境资源对农业的贡献很大,环境资源能值占能和率的３０％,高于全国平均值;     

Importance of greater interdisciplinarity and geographic scope when tackling the driving forces behind biological invasions

Invasive non-native species are important drivers of ecosystem change, yet the driving forces of biological invasions themselves are poorly understood. Such information is essential to ensure policies focus on the most relevant drivers, and that future scenarios capture the full range of potential outcomes for invasive non-native species. I carried out a bibliometric analysis of articles published from 2000 to 2020 that address either invasive non-native species or biodiversity and ecosystem services and that also mention 1 or more drivers of ecosystem change. I examined 5 indirect drivers (demographic, economic, governance, sociocultural, and technological) and 6 direct drivers (climate change, invasive non-native species, land-use or sea-use change, natural hazards, pollution, and resource extraction). Using the Web of Science core collection of citation indexes, I undertook searches of article titles and keywords and retrieved 27,462 articles addressing invasive non-native species and 110,087 articles dealing with biodiversity or ecosystem services. Most research to date on biological invasions as well as on biodiversity and ecosystem services has focused on anthropogenic direct drivers of ecosystem change rather than indirect drivers. Yet currently, less than 18% of articles addressing biological invasions examined drivers of ecosystem change, a similar level to that found over 20 years ago for biodiversity or ecosystem services. Knowledge of the drivers of biological invasions is limited, emphasizes tractable drivers over those that require an interdisciplinary approach, and is biased toward developed economies. Drivers generally deemed important for biological invasions, such as governance and resource extraction, accounted for less than 2% of research effort. The absence of a systematic understanding of the forces that drive invasive non-native species and how they interact means that attempts to mitigate or forecast biological invasions are likely to fail. To address biological invasions requires a much better orientation of national and international research on drivers in relation to both their actual importance as well as their policy relevance.     

Mitigating the effects of climate change on the nests of sea turtles with artificial irrigation

For sea turtles, like many oviparous species, increasing temperatures during development threaten to increase embryonic mortality, alter offspring quality, and potentially create suboptimal primary sex ratios. Various methods are being implemented to mitigate the effects of climate change on reproductive success, but these methods, such as breeding programs, translocations, and shading, are often invasive and expensive. Irrigation is an alternative strategy for cooling nests that, depending on location, can be implemented relatively quickly and cheaply. However, multiple factors, including ambient conditions, nest substrate, and species characteristics, can influence irrigation success. Additionally, irrigation can vary in duration, frequency, and the volume of water applied to nests, which influences the cooling achieved and embryonic survival. Thus, it is critical to understand how to maximize cooling and manage risks before implementing irrigation as a nest-cooling strategy. We reviewed the literature on nest irrigation to examine whether artificial irrigation is feasible as a population management tool. Key factors that affected cooling were the volume of water applied and the frequency of applications. Embryonic responses varied with species, ambient conditions, and the timing of irrigation during development. Nest inundation was the key risk to a successful irrigation regime. Future irrigation regimes must identify clear targets, either primary or adult sex ratios, that maximize population viability. Monitoring population responses and adjusting the irrigation regime in response to population characteristics will be critical. Most studies reported on the manipulation of only one or two variables, further research is required to understand how altering multiple factors in an irrigation regime influences the cooling achieved and embryonic responses.     

Positive and Negative Effects of a Threatened Parrotfish on Reef Ecosystems

Species that are strong interactors play disproportionately important roles in the dynamics of natural ecosystems. It has been proposed that their presence is necessary for positively shaping the structure and functioning of ecosystems. We evaluated this hypothesis using the case of the world's largest parrotfish (Bolbometopon muricatum), a globally imperiled species. We used direct observation, animal tracking, and computer simulations to examine the diverse routes through which B. muricatum affects the diversity, dispersal, relative abundance, and survival of the corals that comprise the foundation of reef ecosystems. Our results suggest that this species can influence reef building corals in both positive and negative ways. Field observation and simulation outputs indicated that B. muricatum reduced the abundance of macroalgae that can outcompete corals, but they also feed directly on corals, decreasing coral abundance, diversity, and colony size. B. muricatum appeared to facilitate coral advancement by mechanically dispersing coral fragments and opening up bare space for coral settlement, but they also damaged adult corals and remobilized a large volume of potentially stressful carbonate sediment. The impacts this species has on reefs appears to be regulated in part by its abundance—the effects of B. muricatum were more intense in simulation scenarios populated with high densities of these fish. Observations conducted in regions with high and low predator (e.g., sharks) abundance generated results that are consistent with the hypothesis that these predators of B. muricatum may play a role in governing their abundance; thus, predation may modulate the intensity of the effects they have on reef dynamics. Overall our results illustrate that functionally unique and threatened species may not have universally positive impacts on ecosystems and that it may be necessary for environmental managers to consider the diverse effects of such species and the forces that mediate the strength of their influence. Efectos Positivos y Negativos de un Pez Loro Amenazado Sobre Ecosistemas Arrecifales     

Form-specific fragances fromOphrys insectifera L. (Orchidaceae) attract species of different pollinator genera. Evidence of sympatric speciation?

Two closely related forms ofOphrys insectifera were observed in the field to attract different pollinator species selectively.O. i. ssp.insectifera attracted males of two species ofArgogorytes (Sphecidae, Hymenoptera Aculeata) andO. i. ssp.aymoninii attractedAndrena combinata males (Andrenidae, Apoidea, Hymenoptera Aculeata). A third form,O. aff.i. ssp.insectifera, attracted none of these three species. Volatile compounds from flowers and inflorescences of the three forms (originating from Öland, Sweden, and Aveyron, France) were collected, using entrainment, enfleurage, and solvent extraction techniques, and identified by gas chromatography — mass spectrometry. Scent differences between the three forms were confirmed in the amounts of aliphatic hydrocarbons (C₁₁–C₁₉), methyl esters (C₁₄–C₁₈), short chain aliphatic 1-alcohols (C₆–C₁₂), and monoterpene alcohols (C₁₀).     

Estimation of the surface stress from the streamwise pressure gradient: The Kármán Integral Momentum Equation revisited

A method is developed to estimate the stress at the surface in a portable wind tunnel for wind erosion studies. The boundary layer height and the pressure gradient are used in a simple expression from the Kármán Integral Momentum Equation. Values of friction velocity u _* are within 10% of experimental values obtained through correlation techniques, including measurements of differential pressures with the Murdoch Turbulence Probe MTP and the X-wire, hot-wire anemometer XWA. Wind velocity and stress profiles reveal logarithmic trends and a constant stress layer near the surface in the DAWA portable wind tunnel. Realignment of the statistics with the mean wind is essential.     

Using decision science to evaluate global biodiversity indices

Global biodiversity indices are used to measure environmental change and progress toward conservation goals, yet few indices have been evaluated comprehensively for their capacity to detect trends of interest, such as declines in threatened species or ecosystem function. Using a structured approach based on decision science, we qualitatively evaluated 9 indices commonly used to track biodiversity at global and regional scales against 5 criteria relating to objectives, design, behavior, incorporation of uncertainty, and constraints (e.g., costs and data availability). Evaluation was based on reference literature for indices available at the time of assessment. We identified 4 key gaps in indices assessed: pathways to achieving goals (means objectives) were not always clear or relevant to desired outcomes (fundamental objectives); index testing and understanding of expected behavior was often lacking; uncertainty was seldom acknowledged or accounted for; and costs of implementation were seldom considered. These gaps may render indices inadequate in certain decision-making contexts and are problematic for indices linked with biodiversity targets and sustainability goals. Ensuring that index objectives are clear and their design is underpinned by a model of relevant processes are crucial in addressing the gaps identified by our assessment. Uptake and productive use of indices will be improved if index performance is tested rigorously and assumptions and uncertainties are clearly communicated to end users. This will increase index accuracy and value in tracking biodiversity change and supporting national and global policy decisions, such as the post-2020 global biodiversity framework of the Convention on Biological Diversity.     

Assessing the extent and nature of wildlife trade on the dark web

Use of the internet as a trade platform has resulted in a shift in the illegal wildlife trade. Increased scrutiny of illegal wildlife trade has led to concerns that online trade of wildlife will move onto the dark web. To provide a baseline of illegal wildlife trade on the dark web, we downloaded and archived 9852 items (individual posts) from the dark web, then searched these based on a list of 121 keywords associated with illegal online wildlife trade, including 30 keywords associated with illegally traded elephant ivory on the surface web. Results were compared with items known to be illegally traded on the dark web, specifically cannabis, cocaine, and heroin, to compare the extent of the trade. Of these 121 keywords, 4 resulted in hits, of which only one was potentially linked to illegal wildlife trade. This sole case was the sale and discussion of Echinopsis pachanoi (San Pedro cactus), which has hallucinogenic properties. This negligible level of activity related to the illegal trade of wildlife on the dark web relative to the open and increasing trade on the surface web may indicate a lack of successful enforcement against illegal wildlife trade on the surface web.     

Estimating freshwater turtle mortality rates and population declines following hook ingestion

Freshwater turtle populations are susceptible to declines following small increases in the mortality of adults, making it essential to identify and understand potential threats. Freshwater turtles ingest fish hooks associated with recreational angling, and this is likely a problem because hook ingestion is a source of additive mortality for sea turtles. We used a Bayesian‐modeling framework, observed rates of hook ingestion by freshwater turtles, and mortality of sea turtles from hook ingestion to examine the probability that a freshwater turtle in a given population ingests a hook and subsequently dies from it. We used the results of these analyses and previously published life‐history data to simulate the effects of hook ingestion on population growth for 3 species of freshwater turtle. In our simulation, the probability that an individual turtle ingests a hook and dies as a result was 1.2–11%. Our simulation results suggest that this rate of mortality from hook ingestion is sufficient to cause population declines. We believe we have identified fish‐hook ingestion as a serious yet generally overlooked threat to the viability of freshwater turtle populations.     

Content analysis of newspaper coverage of the Florida panther

Populations of large carnivores are declining globally, and analysis of public discourse about carnivores is useful for understanding public opinion and influences on management and policy. Portrayal of carnivores in the media affects public perceptions and support for their conservation. We conducted a content analysis of 513 articles about Florida panthers (Puma concolor coryi) published from 2003 to 2006 in newspapers with local circulation in core panther habitat in southwest Florida and papers with statewide circulation to compare the differences in the amount of coverage and portrayals of panther risks to people and property on the basis of proximity of human communities to panthers. Local papers published significantly more news articles and significantly longer news articles primarily about panthers. Articles in local and statewide papers used both episodic frames, which focus on specific occurrences (e.g., a panther sighting or predation) and thematic frames, which focus on general trends (e.g., abundance of panthers over time). Local articles more often emphasized risks that panthers might harm people, pets, or livestock than statewide papers. Our results are consistent with theory that proximity to human-carnivore conflict influences perceptions and salience of risks posed by large carnivores. Most articles mentioned panthers as a secondary topic, which we believe was a result of the relevance an endangered carnivore has in discussions of public land management, development, and regulations in Florida. Claims made by sources quoted in each article had a neutral to positive depiction of panthers, and most quotations were from federal and state agency scientists. We suggest continued use by the media of agency sources provides the opportunity for clear, concordant messages about panther management. Content analysis provides a way to monitor media portrayal of carnivores for consistency with agency outreach goals.