基于上升性理论的重庆市生态经济系统投入产出分析

从信息论的角度入手,运用上升性理论对生态经济系统增长、发展与环境质量进行定量地描述。以重庆市为例讨论了上升性理论在生态经济系统中的应用,利用投入产出表的延长表来计算产业废弃物的排放量,并利用产业废弃物的排放量来反映环境质量状况,把环境质量变化归因于受系统总吞吐量的规模效应、技术效应和结构效应的共同影响。研究结果表明,在1990-1999年重庆市生态经济系统实物型总吞吐量年均增加7.40%,上升性(A)增加近4倍,但是平均相互信息却从0.447比特降到0.342比特,废气排放量年均增长1.1%,废水排放年均增长率达3.2%,根据上升性理论表明在这10a间重庆市生态经济系统处于不可持续的发展状况。在1999-2006年,重庆市生态经济系统实物型总吞吐量仍不断增加,但年均增加率从1999-2006年的7.40%降到3.91%,上升性(A)增加了2倍多,平均相互信息从0.342比特增加到0.478比特,废气排放量的年均下降2.5%,废水排放量年均下降3.7%,这表明在这7a间重庆市生态经济系统朝着良性方向发展。要实现重庆市的生态经济系统良性发展,需提高资源在生态经济系统中的利用效率,实现资源的循环利用,加强资源在生态经济系统中各部门之间的流通性。     

应用生态网络分析方法评价中国经济系统的可持续性

将生态网络分析方法应用于中国经济系统的可持续性分析。依据1987—2010年的投入产出数据,构建中国经济系统的货币网络流,用生态网络指标量化经济系统的网络特征和变化情况,探讨中国经济系统中增长与发展的变化及其可持续性。主要结论有:(1)1987—2010年间中国经济系统的总吞吐量呈指数增长趋势,网络规模不断增长。(2)1987—2010年间中国经济的系统效率在波动中呈增加趋势,但增长幅度较小。从长期阶段看,1997—2010年间的系统效率和组织能力比1987—1995年间有明显提高,表明经济系统在后期获得了一定程度的发展。但系统效率在2002年达到高点后呈现下降趋势。(3)1987—2010年间中国经济系统的上升性和发展能力都在持续提高,但主要来自规模增长。增长和发展的量化结果表明,1987—2010年间中国经济系统上升性的提高,90%来自总吞吐量(增长),只有10%来自效率改进(发展)。(4)1987—2010年间的中国经济系统的α平均值为0.138,远小于0.37或0.33的可持续性最优平衡点,系统处于缺乏效率的不可持续的状态。要提高经济系统的可持续性,需要提高经济系统的效率(结构)和组织能力。     

基于生态足迹方法的西南地区典型资源型城市攀枝花市的可持续发展研究

生态足迹是衡量区域可持续发展程度的重要评价指标。运用生态足迹方法, 估算西南地区典型资源型城市攀枝花市1995-2013 年人均生态足迹及人均生态承载力, 并在此基础上通过生态压力指数、单位万元GDP 生态足迹以及生态可持续指数对攀枝花市生态可持续利用状况进行评价与分析。结果表明：攀枝花市人均生态足迹上升较快尤其是能源生态足迹, 同期人均生态承载力变化趋势较小, 人均生态赤字的变化与人均生态足迹的增长具有同步性, 从1995 年的4.783 hm²·人^-1 增长到2013 的11.74 hm² 人^-1, 人均生态赤字较大; 生态压力指数逐年增加, 2013 达22.15, 较1995 年增长8.69, 生态环境压力较大; 单位万元GDP 生态足迹随着攀枝花市经济转型, 从1995 年的6.14 hm²·万元^-1下降到2013 年的1.72 hm²·万元^-1, 自然资源的利用率有逐年提高的趋势; 但近年来生态可持续指数<0.2, 且有下降趋势, 其可持续发展程度仍属于强不可持续。     

近20年辽宁省森林碳储量及其动态变化

利用辽宁省第3次（1984—1988年）至第6次（1999～2003年）4期森林资源清查资料,采用按优势树种（组）建立与材积兼容的生物量模型,测算辽宁省森林植被的生物量。同时,通过植物分子式的方法确定不同树种的含碳量参数,进而对辽宁省的森林植被碳储量进行了估算。结果表明：1984～2000年,辽宁省森林碳储量从1984年的51．82Tg C增加到2000年的70．30Tg C,年均增长1．16Tg C,森林的碳汇作用显著,尤其是在1990～1995年间的碳汇作用最强。在研究时段内,森林平均碳密度为20．61Mg C／hm^2,并呈现出了先上升后下降再上升的变化趋势。但低于全国平均值,这与目前辽宁省的林龄结构幼、中龄林所占比重很大有关。随着林龄结构的改善,森林成熟度不断增加,碳储量和碳密度会相应增加。     

西北生态脆弱地区甘肃的生态安全时空演化格局

基于区域能值密度改进的能值-生态足迹模型, 结合GIS 以甘肃省为例分析了西北生态脆弱地区生态安全时空演化格局。结果表明: 甘肃省的人均生态赤字呈现波动上升趋势, 人均生态赤字从1980 年的0.42 hm²·cap^-1 增加到2015 年的4.00 hm²·cap^-1, 且以年均6.70%的速度增长, 生态赤字状态在空间上呈现出由中心向两极扩散的演变格局。生态压力指数不断增大, 生态安全等级逐渐升高, 近年来生态安全状况出现恶化趋势, 生态安全问题亟待解决。基于上述结论从降低人类环境负荷和减少化石能源使用量等方面提出了提升生态安全状况的对策措施。     

基于ARIMA模型的生态足迹动态模拟和预测——以甘肃省为例

生态足迹(EF)是一种定量测量人类对自然利用程度的方法。然而目前对其发展趋势准确的定量分析尚不多见。可采用自回归综合移动平均模型(ARIMA)来模拟并预测区域生态足迹。综合运用生态足迹方法和ARIMA模型对甘肃省1949-2009年的生态足迹和生态承载力进行了动态模拟和分析,在此基础上预测了2010-2015年的生态足迹变化趋势。结果表明:1949-2009年,人均生态足迹呈现上升趋势,预计2010-2015年上升趋势明显加快,2015年会增加到2.6051 hm²/人,是2009年的1.67倍;1997-2004年人均生态承载力逐年减少,2005年之后逐年增加,预计2010-2015年仍会增加;预计2010-2015年所有人均生态足迹组成类型均呈现上升趋势,尤以人均化石能源生态足迹增长显著;1997-2009年人均生态承载力均小于人均生态足迹,导致生态赤字,甘肃省生态环境处于不可持续状态,预计2010-2015年人均生态承载力略有增长,但仍小于人均生态足迹,生态赤字不断增大,预计2015年增长到-2.0468 hm²/人,约为2009年(-1.0262 hm²/人)的两倍,甘肃省生态环境不断恶化;经济的发展依赖于化石能源的消耗而造成对自然资源的过度利用,大量耕地转换为建设用地,草地荒漠化是引起甘肃省生态赤字的主要原因;改变经济发展和资源消费模式,控制人口规模,减少人均生态足迹消耗,优化配置和集约节约利用自然资源,提高生态承载力是促进社会经济和资源环境可持续发展的有效途经。     

湖南省生态-经济系统耦合发展探析

从系统论视角出发,剖析了湖南省生态-经济系统内部诸要素及其结构特征,构建评价指标体系;运用定量评价模型,对区域系统的耦合状态进行了分析.结果表明:1996-2006年湖南省综合支撑能力呈对数型上升,而综合消耗水平呈指数型上升,二者演化速度具有非同步性,耦合度呈快速上升趋势,年均增长4.89度;从2008年起将进入过度开发时期,虽然湖南省资源较丰富,但远未具备过度开发型的物质条件;湖南省进入过度开发时期的原因是,在经济增长方式仍然非常落后和产业结构未得到有效调整的情况下,一味突出出口导向型经济,从而导致综合消耗水平发展快速增长.     

内蒙古多伦县土地沙漠化景观格局变化特征

利用景观分析软件Fragstats 3.3和内蒙古多伦县1960、1975、1987、1995、2000、2005年6期遥感影像解译结果,分析了1960—2005年间土地沙漠化景观格局变化.结果表明:1960—1995年间研究区土地沙漠化面积呈先增后减趋势,总沙漠化面积增加212.70km2,沙漠化斑块数先增多后减少,景观多样性和均匀性上升,轻度、中度、重度沙漠化斑块形状趋向简单;1995—2005年间研究区沙漠化斑块数大幅增加,景观多样性和均匀性下降,轻度、中度、重度沙漠化斑块形状趋向复杂;严重沙漠化斑块形状在1960年以后一直趋向复杂化.整个景观在研究期间表现为完整-破碎-完整-破碎的趋势,由轻度到严重沙漠化,其景观类型的破碎化程度逐渐降低.     

未来气候变化对黄土高原黑河流域水资源的影响

气候变化对黄土高原的水资源有重要影响,对其影响进行评估可以为区域发展提供重要的决策依据.基于分布式水文模型SWAT和4种全球环流模式的各3种排放情景,评估了2010～2039年黄土高塬沟壑区黑河流域水资源对气候变化的潜在响应.结果表明,黑河流域2010～2039年的年均降水变化-2.3%～7.8%,年均最高和最低温度分别升高0.7～2.2 ℃和1.2～2.8 ℃,年均径流量变化-19.8%～37.0%,1.2 m剖面年均土壤水分含量变化-5.5%～17.2%,年均蒸散量普遍增长0.1%～5.9%;水文气象变量变化趋势复杂,但T检验表明年降水、径流、土壤水分和蒸散增长的概率较大.对于季节变化,降水可能在12～7月份和9月份增长,8月份和10～11月份减少;径流在4～7月份和9～10月份增加,11～3月份和8月份减少;土壤水分在各月都增长;蒸散11～6月份普遍增长,7～10月份减少的可能性较大.未来气候将发生显著变化并对水资源有重要影响,需采取必要的措施来减缓其不利影响.     

西安市温室气体排放的动态分析及等级评估

为了解西安市温室气体排放的动态规律和排放水平,基于全球标杆的温室气体排放等级评价方法,并采用国际公认的《2006年IPCC国家温室气体清单指南》和基于IPCC的《省级温室气体编制指南》推荐的方法对西安市的温室气体排放进行了动态分析和排放等级评估。结果表明,从1995年到2011年,西安市温室气体排放呈快速上升趋势,16年间温室气体排放量从1207.16×104t上升为3934.17×104t,年均增高7.66%。增幅最高的是水泥温室气体(年均增高11.75%)、废弃物(8.77%)和能源(7.63%),农业年均降低1.74%,林业固碳年圴增加3.56%。从温室气体构成看,能源占80.13%—90.55%,水泥占1.75%—7.49%,农业占1.86%—8.01%,林业固碳占-2.58%—-5.22%,废物处理占7.52%—16.38%。可见能源消费的增加是导致西安市温室气体排放增长的主要原因,林业碳汇能力有待提高。万元GDP温室气体排放不断降低,说明西安市碳减排方面的科技进步在不断提高。人均、单位面积温室气体排放量和排放指数增速很快,年均增幅分别达5.84%、7.66%和6.84%。西安市温室气体排放等级持续增高,16年间从较低等级(Ⅰc)上升为中下等级(Ⅱa),目前距应对气候变暖目标(Ⅰb)已高出两个亚级,温室气体排放增高的趋势不容忽视。     

MicroRNA in cell differentiation and development

The regulation of gene expression by microRNAs (miRNAs) is a recently discovered pattern of gene regulation in animals and plants. MiRNAs have been implicated in various aspects of animal development and cell differentiation, such as early embryonic development, neuronal development, muscle development, and lymphocyte development, by the analysis of genetic deletions of individual miRNAs in mammals. These studies show that miRNAs are key regulators in animal development and are potential causes of human diseases. Here we review some recent discoveries about the functions of miRNAs in cell differentiation and development. Supported by National Key Basic Research and Development Program of China (Grant No. 2005CB724602) and Knowledge Innovation Project of the Chinese Academy of Sciences (Grant Nos. KSCX2-YW-R-096, KSCX1-YW-R-64)     

Conserving global biological diversity by encouraging alternative development paths: can development coexist with diversity?

The conservation of biological diversity concerns the management of the development process, not only at the national but also at the global level. Individual countries have made their development choices independently but relatedly, too often following the precise form of the choices of other countries preceding them in the development process. Development via imitation is pursuing the form, rather than the substance of a successful development strategy. Countries should instead be developing upon a base of assets that provides them with a relatively unique set of goods and services to place upon global markets. When the first countries developed, this criterion indicated that they should convert their countries to new forms of production; when the last countries are developing, relatively unique goods and services flow from their lands as they stand. What is required is the development of global institutions that encourage countries to see that their best development opportunities lie down these alternative development pathways, based upon their already-existing but relatively unique national assets.     

In vitro cultivation of Fasciola hepatica metacercariae and of partially developed flukes recovered from mice

Attempts were made to culture the metacercariae of Fasciola hepatica under a wide variety of conditions. Of the media tested, the most successful was NCTC 135 plus 50% heat inactivated chick serum and sheep red blood cells at 37°–38°C. In this medium, somatic development of newly excysted juveniles was similar to that of flukes recovered from the liver of a mouse 11 days post-infection. There was, however, no corresponding development of the genital rudiment. Various supplements, such as liver extract, bile, yeast extract, embryo extract, egg products, monolayer cells and diphasic media were tested, but none enhanced development. The effects of various physical parameters on growth and development in vitro were examined. Cultured metacercariae appeared to be in a state of ‘suspended animation’; when injected intraperitoneally into mice they developed into egg-producing adults. Flukes recovered from the abdomen and liver of mice continued their somatic growth in vitro but their genitalia failed to develop further.     

Characterization of Sgo1 expression in developing and adult mouse

SGO1 has been characterized in its function in correct cell division and its role in centrosome cohesion in the nucleus. However, its organ-specific maturation-related expression pattern in vivo remains largely uncharacterized. Here, we show clear SGO1 expression in post-developmental neuronal cells and cytoplasmic localisation in nucleated cells with a transgenic mice model and immunohistochemistry of wild type mice. We demonstrate extranuclear expression of Sgo1 in the developing heart and gut, which have been shown to be dysregulated in humans with homozygous SGO1 mutation. Additionally, we show Sgo1 expression in select population of retinal cells in developing and post-developmental retina. Our expression analysis strongly suggests that the function of SGO1 goes beyond its well characterized role in cell division.     

MicroRNA与动物发育

MicroRNA(miRNA)是一类约22nt大小的内源性非编码RNA,它们通过剪切靶基因的转录产物或者抑制转录产物的翻译从而起到转录后调控靶基因表达的作用。在动物体内,通过基因敲除等方法所进行的大量研究表明了miRNA参与了胚胎早期发育、脑及神经发育、心脏发育、肌肉及骨骼发育等动物发育的各个方面。miRNA是动物发生发育过程中重要的调控因子。主要介绍了近年来miRNA在动物生长发育过程中的研究进展。     

A requirement for Fgfr2 in middle ear development

The skeletal structure of the mammalian middle ear, which is composed of three endochondral ossicles suspended within a membranous air‐filled capsule, plays a critical role in conducting sound. Gene mutations that alter skeletal development in the middle ear result in auditory impairment. Mutations in fibroblast growth factor receptor 2 (FGFR2), an important regulator of endochondral and intramembranous bone formation, cause a spectrum of congenital skeletal disorders featuring conductive hearing loss. Although the middle ear malformations in multiple FGFR2 gain‐of‐function disorders are clinically characterized, those in the FGFR2 loss‐of‐function disorder lacrimo‐auriculo‐dento‐digital (LADD) syndrome are relatively undescribed. To better understand conductive hearing loss in LADD, we examined the middle ear skeleton of mice with conditional loss of Fgfr2. We find that decreased auditory function in Fgfr2 mutant mice correlates with hypoplasia of the auditory bulla and ectopic bone growth at sites of tendon/ligament attachment. We show that ectopic bone associated with the intra‐articular ligaments of the incudomalleal joint is derived from Scx‐expressing cells and preceded by decreased expression of the joint progenitor marker Gdf5. Together, these results identify a role for Fgfr2 in development of the middle ear skeletal tissues and suggest potential causes for conductive hearing loss in LADD syndrome.     

The role of oxygen availability in the embryonation of Heterakis gallinarum eggs.

The importance of oxygen availability in the embryonation of the infective egg stages of the gastrointestinal nematode parasite Heterakis gallinarum was studied in the laboratory. Unembryonated H. gallinarum eggs were kept under either aerobic conditions by gassing with oxygen, or anaerobic conditions by gassing with the inert gas nitrogen, under a range of constant temperatures. Oxygenated eggs embryonated at a rate influenced by temperature. Conversely, eggs treated with nitrogen showed no embryonation although when these eggs were transferred from nitrogen to oxygen gas after 60 days of treatment, embryonation occurred. This demonstrated that oxygen is an essential requirement for H. gallinarum egg development, although undeveloped eggs remain viable, even after 60 days in low oxygen conditions. The effects of climate on the biology of free-living stages studied under constant laboratory conditions cannot be applied directly to the field where climatic factors exhibit daily cycles. The effect of fluctuating temperature on development was investigated by including an additional temperature group in which H. gallinarum eggs were kept under daily temperature cycles between 12 and 22°C. Cycles caused eggs to develop significantly earlier than those in the constant mean cycle temperature, 17°C, but significantly slower than those in constant 22°C suggesting that daily temperature cycles had an accelerating effect on H. gallinarum egg embryonation but did not accelerate to the higher temperature. These results suggest that daily fluctuations in temperature influence development of the free-living stages and so development cannot be accurately predicted on the basis of constant temperature culture.     

Patterns in stage duration and development among marine and freshwater calanoid and cyclopoid copepods: a review of rules,physiological constraints,and evolutionary significance

Studies of development time of marine and freshwater copepods have taken separate tracks. Most studies on marine copepods report development time of each individual development stage, whereas studies on freshwater copepods report only development time, from egg to nauplius and nauplius to adult. This bias allows comparison of total development time but prevents detailed comparisons of patterns in stage-specific developmental schedules. With respect to egg to adult development time, three general relationships are known: developmental rates are dependent upon temperature and food concentration but independent of terminal body size; freshwater calanoids develop significantly slower than marine calanoids; freshwater cyclopoids develop at the same rate as marine calanoids. Two rules describe stage-specific developmental rates: the equiproportional rule and the isochronal rule. The first rule states that the duration of a given life history stage is a constant proportion of the embryonic development time; the second rule states that the time spent in each stage is the same for all stages. This review focuses on the second rule. From the 80+ published studies of copepod stage-specific developmental times, no species follows the isochronal rule strictly: Acartia spp. come closest with isochronal development from third nauplius (N3) to fourth copepodite (C4). The only pattern followed by all species is rapid development of the first and/or second naupliar stages, slow development of the second and/or third nauplius and prolonged development of the final copepodite stage. Once adulthood is reached, males are usually short-lived, but females can live for weeks to months in the laboratory. Adult longevity in the sea is, however, on the order of only a few days. The evolution of developmental patterns is discussed in the context of physiological constraints, along with consideration of possible relationships between stage-specific mortality rates and life history strategies. Physiological constraints may operate at critical bottlenecks in development (e.g. at the first feeding nauplius, N6, and the fifth copepodite stage). High mortality of eggs may explain why broadcast eggs hatch 2–3 times faster than eggs carried by females in a sac; high mortality of adults may explain why adults do not grow rather they maximize their reproductive effort by partitioning all energy for growth into egg production.