Use of Complex Adaptive Systems for Modeling Global Change

Global modeling has been used for decades to assess the possible futures of humanity and the global environment. However, these models do not always satisfactorily include the adaptive characteristics of systems. In this article, a general approach is used to simulate change and transition at a macrolevel due to adaptation at a microlevel. Tools from complex adaptive systems research are used to simulate the microlevel and consequently determine parameter values of the equation-based macrolevel model. Two case studies that applied this approach are reviewed. The first study assessed the efficacy of efforts to control malaria, whereas the second study used an integrated model to construct climate change scenarios by using various possible views on the nature of the climate system. Received 14 April 1998; accepted 7 July 1998.     

Study on Climate Vegetation Classification for Global Change in China

The study on climate-vegetation relationship is the basis for determining the re sponse of terrestrial ecosystem to global change. By means of quantitative analysis on climate-vegetation interaction, vegetation types and their distribution pattern could be corresponded with certain climatic types in a series of mathematical forms. Thus, the climate could be used to predict vegetation types and their distribution, the same is in reverse. Potential evapotranspiration rate is a comprehensive climatological index which combines temperature with precipitation, and could be used to evaluate the effect of climate on vegetation. In this respect, Holdridge life zone system has been drawing much attention and widely applied internationally owing to its simplicity. It is especially used in the assessment of sensibility of terrestrial ecosystems and their distribution in accordance with climate change and in prediction of the changing pattern of vegetation under doubled CO2 condition. However, Prentice (1990) pointed out that the accurancy of Holdridge life zone system is less than 40 % when it is used at global scale. The reason may be that the potential evapotranspiration calculated by Thornthwaite method, which is used in Holdridge life zone system, reflects the potential evapotranspiration from small evaporated area, while climate-vegetation classification is based on the regional scale. The authors try to establish a new climate-vegetation classification system based on the regional potential evapotranspiration. According to the following formula: where E designates regional actual evapotranspiration: Ep local potential evapotran-spiration: Epo, regional potential evapotranspiration. Ed can be calculated from Penman model or other models. E can be calculated from the following model: E=r · Rn (r2+Rn2+r · Rn) / (2) (r+Rn) · (r2+Rn2)where r designates precipitation (mm); Rn, net radiation (mm). Thus, Ep0 can be easily obtained. It is used as the regional thermal index (RTI) of climate-vegetation classification,and can be expressed as: RTl = Epo (3) Moisture index is another index of climate-veggetation classification. Usually, it can be expressed as the ratio between potential evapotranspiration and precipitation. However, this ratio can not reflect soil moisture, which is important for plant. The ratio between regional actual evapotranspiration and regional potential evapotranspiration is associated not only with climatic condition but also with soil moisture. So it can be used as the moisture index of climate-vegetation classification, and is defined as regional moisture index (RMI): RMI = E/Epo (5) Based on the average climatological data of 30 years from 647 meteorological observation stations in China. It was found that RTl could well reflect a regional thermal level. The values of RTI were less than 360 mm in cold temperate zone, 360～650 mm in temperate zone, 650～380 mm in warm temperate zone, 780～1100 mm in subtropical zone. And more than 1100 mm in tropical zone. RMI also reflects a regional moisture level very well. The values of RMI was less than 0.4 in desert area, 0.4～0.7 in grassland area and more than 0.7 in forest area. Thus, the climate-vegetation classification in China is established on the basis of the two indices: RTI and RMI. According to this model, the changing patterns of vegetation zones in China are given under the conditions of mean annual temperature in creasing by 2℃ and 4℃ and mean annual precipitation increasing by 20%. The results showed that the areas of forest and grassland would decrease, the vegetation zones would move northward and upward, and the area of desert would increase. The results also indicate that the Tibetan Plateau is an area highly sensitive to global change. It could be considered as an indicative or forewarning area for global change , and therefore, an area of great siginificance for monitoring and research. The possible beneficial effect of global change on China terrestrial ecosystems is that the plantation boundary will move northwards and upwards; and the disadvantageous effect is the expansion of desertification and the increase of instability in climatic conditions.     

天南星科分类系统的沿革

天南星科 Araceae是一个世界性的大科 ,计1 0 5属约 3 5 0 0余种 [1]。单子叶植物 ,与浮萍科组成 1个目。在中国植物志排在第 1 3卷 ,第 2分册 [2 ]。其分布区跨越从赤道带到寒温带的各个生态地带 ,散布于新旧世界的各大陆块 ,仅在一些海岛地区和南美大陆有较多空白点 [3 ] 。中国有 2 6属 2 0 0余种[4 ] ,种属数量都不多 ,但不少属如 Pinellia、Arisaema、Remasatia和 Colocasia等都是以中国为分化中心的。中国最早有关天南星科植物的记载 ,始于本草书籍。西汉时期的“神农本草经”就记载了菖蒲(Acorus calamus) ,虎掌 (Pinellia pedati…     

虎尾草亚科(Chloridoideae)的分类系统述评

简要介绍了禾本科虎尾草亚科的分类历史。考察虎尾草亚科属上阶元的变化过程,概括不同时期该亚科分类学研究的进展及分类原则,对3种研究方法的不足进行评价。自1990年《中国植物志》第10卷第1分册出版以来,对中国虎尾草亚科植物属种水平的系统变化进行了说明。为了更好地理解虎尾草亚科的系统发育关系,指出了虎尾草亚科没有解决的问题及今后的研究方向。     

Global Climate Change: Benefit-Cost Analysis vs. the Precautionary Principle

The precautionary principle appears to be directly applicable to the prospect that human activities will cause substantial changes to global climate. The magnitude and characteristics of the change in climate and its effects on human activities and unmanaged ecosystems are highly uncertain, potentially catastrophic, and nearly irreversible on human time scales. Nevertheless, the precautionary principle adds little to benefit cost analysis for evaluating climate policies. Benefit cost analysis can incorporate aversion to uncertainty about future outcomes, and also provides a method for balancing this concern against concern for uncertain near term policy costs. The policies favored by setting constraints on future outcomes, such as atmospheric stabilization and tolerable windows, may be less precautionary than the policies favored by benefit cost analysis, as benefit cost analysis can more readily accommodate concerns for moderate as well as severe harms. Concerns about possible climate catastrophes can also be incorporated in benefit cost analysis and, in any event, may have limited implications for policy choice.     

Detecting Tropical Forests' Responses to Global Climatic and Atmospheric Change: Current Challenges and a Way Forward

Because of tropical forests' disproportionate importance for world biodiversity and for the global carbon cycle, we urgently need to understand any effects on these ecosystems from the ongoing changes in climate and atmosphere. This review, intended to complement existing data reviews on this topic, focuses on three major classes of challenges that we currently face when trying to detect and interpret directional changes in tropical forests. One is the very limited existing information on the historical context of study sites. Lasting effects from past climate, natural disturbances, and/or human activities could be significantly affecting current-day processes in tropical forests and need to be investigated for all active field sites. Second, while progress has been made in recent years on standardizing and refining research approaches, a number of methods- and data-limitations continue to affect efforts both to detect within-forest changes and to relate them to ongoing environmental change. Important outstanding needs are improved sampling designs, longer time-series of observations, filling key data gaps, and data access. Finally, forest responses to ongoing environmental change are complex. The effects of many simultaneously changing environmental factors are integrated by the plants, and their responses can involve significant lags, carryovers, and non-linearities. Specifying effects of individual environmental changes, however, is required for accurate ecosystem-process models and thus for projecting future impacts on these forests. After discussing these several types of challenges and ways to address them, I conclude with a priority agenda for this critical area of research.
Abstract in Spanish is available at http://www.blackwell-synergy.com/loi/btp .     

Construction of a Global Pain Systems Network Highlights Phospholipid Signaling as a Regulator of Heat Nociception

The ability to perceive noxious stimuli is critical for an animal''s survival in the face of environmental danger, and thus pain perception is likely to be under stringent evolutionary pressure. Using a neuronal-specific RNAi knock-down strategy in adult Drosophila, we recently completed a genome-wide functional annotation of heat nociception that allowed us to identify α2δ3 as a novel pain gene. Here we report construction of an evolutionary-conserved, system-level, global molecular pain network map. Our systems map is markedly enriched for multiple genes associated with human pain and predicts a plethora of novel candidate pain pathways. One central node of this pain network is phospholipid signaling, which has been implicated before in pain processing. To further investigate the role of phospholipid signaling in mammalian heat pain perception, we analysed the phenotype of PIP5Kα and PI3Kγ mutant mice. Intriguingly, both of these mice exhibit pronounced hypersensitivity to noxious heat and capsaicin-induced pain, which directly mapped through PI3Kγ kinase-dead knock-in mice to PI3Kγ lipid kinase activity. Using single primary sensory neuron recording, PI3Kγ function was mechanistically linked to a negative regulation of TRPV1 channel transduction. Our data provide a systems map for heat nociception and reinforces the extraordinary conservation of molecular mechanisms of nociception across different species.     

Sensitivity Analysis of Individual Responses of Plants to Global Change

Today research on global change is becoming one of the three vital topics in ecology. Within this field, simulating an individual plant’s physiological responses to global change, especially the combined effects of CO2 enrichment and the climatic change it caused, is a useful model in predicting the changes of either natural vegetation or agricultural crops, in that the physiological basis of the responses are mostly understood and the results of simulation can be checked with experi ments at any level or step when needed. Since the scenarios of the global changes often differ with different GCM’s, and will change as the GCM’s are being improved, even though, the simulation programs can still be used to for new predictions. In this study, based on the physiological mechanisms, a systematic dynamic model of plant individual growth was established, which included a weather generator and a growth module. The combined effects of enriched CO2 and climatic change on the main physiological processes, such as photosynthesis, respiration, etc., and seasonal dynamics of biomass were considered in the model. The data sets of the long-term weather records of Beijing Meteorological Station and the observed values of many ecophysiological quantities, obtained in a CO2 enrichment experiment of soybean, were used to parameterize and to validate the model. The results showed that data obtained from the simulation were quite compatible with those from the observation. When the CO2 concentration was doubled, the peak values of the total biomass and green biomass were increased approximately by 70% and 56% respectively. Furthermore, the responses of the total net assimilation and the average specific dark respiration rate within the growth season explained the internal mechanism of the biomass responses. The result indicated that the total net assimilation increased, while the average specific dark respiration rate decreased. Thus, it can be deduced that the increase of biomass was brought about not only by the increase of the net assimilation, but also by 'the decrease of the specific dark respiration rate. Sensitivity analysis was used to the soybean individual responses to global change. The seasonal dynamics of the total biomass to the combined effects of different levels of CO2, temperature and precipitation were simulated. CO2 concentration and precipitation have positive, while temperature has negative effect on total biomass. The positive effect of precipitation became weaker with increasing temperatures, while the negative effect of temperature was strengthened by the increased precipitation. The positive effect of CO2 concentration became stronger with the increasing temperatures, but weaker under enhancing precipitations. The positive effect of precipitation and the negative effect of temperature were weakened by doubling the CO2 concentration. These are partly due to the enhanced water use efficiency caused by CO2 enrichment, which in turn renders the plant individual more resistant and adaptable to the environmental change.     

全球变化与野生物种:观测和预测

由于人类活动的影响,世界正在变暖。迅速的全球变化很可能对野生物种产生巨大影响,同时伴随着城市化、农垦和造林实践所引起的自然生境的丧失和破坏。观测和预测的气候变化对野生物种的影响着眼于4个方面：生活史的时间、物种分布与种群格局、迁移对策以及重要地点。许多物种可能因气候的变化而灭绝,而气候变化所造成的野生物种分布的变化很可能对人类产生长期久远的影响。     

Climate Analysis of Endemic Species-A Novel Method for Quantitative Analysis of Global Climate Change Since Tertiary

There are many extant endemic plants in China, which were widely distributed in the North Hemisphere during Tertiary. The global cooling during the Tertiary caused a series of narrow distribution regions of the plants. Quaternary glaciation invaded most regions of North America and Eurasia where severe destruction was imposed onto vegetation. However, such destruction was lessened in China largely because of specific topographic and geographical and obviously, a number of other conditions accounted for an unusual refugee camp for the relics of plants in China, among which lots of endemic taxa exist. Recently, Chinese endemic species, such as Metaseqouia, Eucommia , have been employed to conduct multi-disciplinary comprehensive studies so as to analyze Tertiary climate changes quantitatively. Meanwhile, a rigorous method, i.e. climate analysis of endemic species (CAES) has come to maturation. This method is characteristic of some generality because it is supposed to be applicable to the endemic species in other regions of the world. CAES is involved in the following aspects: 1. Conduct multidisciplinary studies on living and fossil species of endemic plants and trace their evolutionary courses. 2. Compare fossil species with living one and clarify which is the nearest living relative (NLR) to fossil counterpart. 3. Fossils and their living counterparts (NLR) are supposed to have similar ecological requirements to meet their life cycles. 4. Investigate the geographic distribution of living and fossil plants within the same taxa and ascertain the dynamic changes of their distributions in geological age. 5. Analyze climate factors in the distribution of specific endemic taxa and obtain the data of climatic characters which are suitable for reconstruction of paleoclimate where fossil counterparts lived. 6. Further study the physio-ecology of living species and determinate paleoclimate where fossil counterparts lived. 7. Integrate analysis of the data from steps 4, 5 and 6, and quantitatively reconstruct the climate where fossil and living plants survive.     

全球双特异性抗体药物研发格局分析*

过去十年,全球双特异性抗体研发取得了突破性进展,4款产品获批上市,多个产品进入临床及临床前研究。双抗具有区别于单抗的独特生物学机制,有望成为针对癌症、自身免疫和传染病的下一代生物疗法,但双抗药物的开发更具复杂性,有着更高的技术壁垒。通过对全球双抗总体研发进展、企业研发格局、产品研发进展等角度分析,以期为相关企业的双抗研发方向选择及地区产业决策提供参考。     

Global Environmental Change and Population Health: Progress and Challenges

Escalating global environmental change (GEC) over the past century has been driven largely by rapid industrialization, population growth, overconsumption of natural resources, and associated waste disposal challenges, as well as the inappropriate uses of technology. These changes are already having and will increasingly continue to have significant impacts on human health and well-being. How to tackle these issues is an important challenge to scientists, policy-makers, and the general public. Scientific consensus now exists that GEC and population health are linked, even though the details and mechanisms underlying this link remain to be both explicated and quantified. In this article we provide an overview of progress and challenges in the area of GEC and population health since the late 1980s, highlighting some of the main landmarks in this area and recommending directions for future research.     

Desiccation Tolerance and Global Change: Implications for Tropical Bryophytes in Lowland Forests

Global change puts an increasing pressure on tropical forests and their inherent diversity by the risk of longer droughts and drier microclimatic conditions within the forest. How organisms will respond is uncertain, especially for organisms highly depending on their microclimatic environment such as bryophytes. An adequate tolerance to desiccation is important to face these changes, however, little is known for tropical bryophytes. We investigated for the first time the desiccation tolerance of epiphytic bryophytes from contrasting microsites at the tropical lowland forest in French Guiana. Using chlorophyll‐fluorescence (F_v/F_m) as an indicator of recovery, we tested: (1) desiccation tolerance for short (3 d) and long (9 d) desiccation events; (2) different desiccation intensities; and (3) recovery by rehydration with water vapor. Species from the canopy were well adapted to desiccation events. Thirteen of 18 species maintained more than 75 percent of their photosynthetic capacity after recovery at the strongest desiccation treatment of 9 d at 43 percent relative humidity (RH). In contrast, species from the understory were sensitive and withstood desiccation only at humid conditions of 75 percent RH and higher. The photosystem of the studied bryophytes was reactivated efficiently in equilibration with water vapor only—a yet neglected phenomenon in bryology. A novel introduced desiccation tolerance index allows global comparison of desiccation tolerances and highlights the sensitivity of understory species. Our results suggest that decreasing humidity caused by climate change and forest degradation could be a concerning threat for understory species.     

Cephalopod and Groundfish Landings: Evidence for Ecological Change in Global Fisheries?

Cephalopod fisheries are among the few still with some local potential for expansion; in fact, as groundfish landings have declined globally, cephalopod landings have increased. We propose the hypothesis that, although increased cephalopod landings may partly reflect increased market demand, overfishing groundfish stocks has positively affected cephalopod populations. Data from 15 key FAO areas reveal that, with the exception of the north- east Atlantic, cephalopod landings have increased significantly over the last 25 years while groundfish have risen more slowly, remained stable, or declined. In terms of volume, cephalopods have not replaced groundfish. This is hypothesized as owing to the shorter life cycle of cephalopods, and rapid turnover and lower standing stocks than for longer-lived finfish species. Under high fishing pressure, groundfish are probably poor competitors, having less opportunity for spawning and replacement. In West Africa, the Gulf of Thailand and Adriatic there is strong circumstantial evidence that fishing pressure has changed ecological conditions and cephalopod stocks have increased as predatory fish have declined. We recommend that this hypothesis be tested thoroughly in other areas where suitable data exist. Most coastal and shelf cephalopod fisheries are likely to be fully exploited or overexploited, and current annual fluctuations in cephalopod landings are probably largely environmentally-driven.     

Global Climate Change Adaptation Priorities for Biodiversity and Food Security

International policy is placing increasing emphasis on adaptation to climate change, including the allocation of new funds to assist adaptation efforts. Climate change adaptation funding may be most effective where it meets integrated goals, but global geographic priorities based on multiple development and ecological criteria are not well characterized. Here we show that human and natural adaptation needs related to maintaining agricultural productivity and ecosystem integrity intersect in ten major areas globally, providing a coherent set of international priorities for adaptation funding. An additional seven regional areas are identified as worthy of additional study. The priority areas are locations where changes in crop suitability affecting impoverished farmers intersect with changes in ranges of restricted-range species. Agreement among multiple climate models and emissions scenarios suggests that these priorities are robust. Adaptation funding directed to these areas could simultaneously address multiple international policy goals, including poverty reduction, protecting agricultural production and safeguarding ecosystem services.