现代科学技术中的生态研究问题

环境污染、生态问题是当今世界所面临的主要问题,研究环境的保护与改善,首先必须解决生态失调问题。生态问题已成为众多学科涉足研究的课题。生态学的基本理论和方法就客观成为各学科处理生态问题所依据的准则,     

A Scooter Inquiry: An Integrated Science,Mathematics, and Technology Activity

The authors illustrate an effective lessonplanning technique known as unpacking for the broad topic of water. Interconnections among science disciplines are shown for numerous possible subtopics. Two lesson sets are included, the first dealing with properties of water and the second dealing with water as a resource.     

Social foraging: individual learning and cultural transmission of innovations

We present two stochastic models of individual and social learningthat count the number of individuals exhibiting a learned, resource-producingtrait in a group of social foragers. The novelty of our modelingresults from incorporating the empirically based assumptionthat rates of both individual and social learning should dependon the frequency of the learned trait within the group. Whenresources occur as clumps shared by group members, a naive individual'sacquisition of the skill required for clump discovery/productionshould involve opposing processes of frequency dependence. Theopportunity to learn via cultural transmission should increasewith the trait's frequency, but the opportunity for learningindividually should decrease as the trait's frequency increases.The results of the model suggest that the evolution of the capacityfor cultural transmission may be promoted in environments wherescrounging at resource clumps inhibits rates of individual learning.     

Implementing the Precautionary Principle: Rigorous Science and Solid Ethics

The Precautionary Principle came out of European efforts to clean-up and protect marine ecosystems in the 1980s. Since then, several North American activities have elaborated on this approach in U.S. environmental programs. Unfortunately, US organizations and agencies have not developed strategies and guidelines for implementing the Precautionary Principle in either statutory or voluntary environmental programs. Recent interest in this approach from some members of the scientific, non-profit, and regulatory communities highlights the need to understand the history and conceptual basis of the Precautionary Principle. In this paper we address several of these issues. First, we summarize the pertinent US history of the Precautionary Principle. Next, we describe the scientific framework for the principle. Finally, we make the case that this provides unique opportunities for scientists to obtain meaning in their work by fulfilling what has been called the new Social Contract.     

Bringing the Moral Economy back in … to the Study of 21st-Century Transnational Peasant Movements

James Scott's The Moral Economy of the Peasant (1976) appeared at a time when "peasant studies" had begun to occupy an important place in the social sciences. The book's focus on Vietnam, as well as its novel argument about the causes of rural rebellion, attracted widespread attention and unleashed acerbic debates about peasants' "rationality" and the applicability of concepts from neoclassical economics to smallholding agriculturalists. In this article, I analyze E. P. Thompson's notion of "moral economy" and Scott's use of it to develop an experiential theory of exploitation. I then discuss other influences on Scott, including Karl Polanyi, A. V. Chayanov, and the Annales historians. "Moral economy" and "subsistence crisis" are concepts that Scott elaborated mainly in relation to village or national politics. In the final section of the article, I outline changes affecting peasantries in the globalization era and the continuing relevance of moral economic discourses in agriculturalists' transnational campaigns against the WTO.     

Social Learning and the Maintenance of Cultural Variation: An Evolutionary Model and Data from East Africa

Human societies maintain between-group variation despite mixing of people and ideas. In order for variation to remain, migrants or their children must preferentially adopt local norms, customs, and beliefs. Yet the details of how cultural variation is maintained, despite mixing, remain unknown. This article addresses this problem by using a simple model of the evolution of cultural learning to interpret the results of a study of cultural variation in a small region of East Africa. I argue that the manner in which migrants of two diverse regions adapt to local beliefs and behavior depends on the costs and accuracy of learning in each domain. Observational studies are never definitive tests of any hypothesis, but these results suggest that conclusions about the significance of cultural learning for understanding individual attitudes and behavior depend strongly upon the domain of investigation.     

新的农业科技革命与农业生态学研究

阐述了以“双重绿芭革命”为主要特征的世界农业科技革命的趋势,指出中国新的农业科技革命是超出世界农业科技革命目标的多重绿色革命。农业生态学是实现多重以革命目标的两大关键技术之一。为了能使生态学家研究在新的农业科技革命中发挥应用的作用,必须进行生态研究的革命,即强化对农业生态学基本生态学过程听研究,面向农产品产量与品质提高的需求,加强产量生态学和品质生态学的研究,针对薄弱环节和社会发展急而开展促进中国     

Neural Coding of Finger and Wrist Movements

Previous work (Schieber and Hibbard, 1993) has shown that single motor cortical neurons do not discharge specifically for a particular flexion-extension finger movement but instead are active with movements of different fingers. In addition, neuronal populations active with movements of different fingers overlap extensively in their spatial locations in the motor cortex. These data suggested that control of any finger movement utilizes a distributed population of neurons. In this study we applied the neuronal population vector analysis (Georgopoulos et al., 1983) to these same data to determine (1) whether single cells are tuned in an abstract, three-dimensional (3D) instructed finger and wrist movement space with hand-like geometry and (2) whether the neuronal population encodes specific finger movements. We found that the activity of 132/176 (75%) motor cortical neurons related to finger movements was indeed tuned in this space. Moreover, the population vector computed in this space predicted well the instructed finger movement. Thus, although single neurons may be related to several disparate finger movements, and neurons related to different finger movements are intermingled throughout the hand area of the motor cortex, the neuronal population activity does specify particular finger movements.     

Local Tree Mapping: A Collaborative,Place-Based Activity Integrating Science,Technology, Math,and Geography

This inquiry-based activity designed for the fifth through 12th grade allows students to engage in an outdoor, place-based experience, working collaboratively both in groups and as a class to accomplish the class goal of creating a local tree map linked to student-collected data about each tree. During Local Tree Mapping, students explore the local trees in the yard or neighborhood of the school, while learning basic skills in geographical information systems and Microsoft Excel. Through this activity, students gain a deeper understanding of and appreciation for the role of trees within the Earth's ecosystems, as they collect data on tree type, height, diameter, age, and the longitude and latitude of the trees. An extension activity is described in which students can enter their tree data into a carbon dioxide (CO₂) emissions reduction calculator to determine how much CO₂ is sequestered by the trees in their research site. Local Tree Mapping provides an opportunity for students to gain inquiry skills in science, mathematics, and geography as they participate firsthand in the collection, analysis, and presentation of real-world data that can be utilized by the local community.     

Movements,status, access to nectar,and spatial organisation of the tui

Abstract

Movements of tui (Prosthetnadera novaeseelandiae) breeding on Tiritiri Matangi Island were followed and related to changes in nectar access. The island has limited nectar sources and birds must move to gain access to nectar year round. All tui leave the island, although the extent and timing of movement varies for different individuals. Tui return for breeding but again the timing of the return varies for individuals. Nectar sources were typically concentrated in both time and space, and access was related to individual asymmetries such as sex, residential status and age. These same asymmetries also relate to the timing of individuals movements, and where individuals nest relative to nectar sources. At concentrated food sources, access was determined by an absolute social hierarchy. Although tui defend exclusive feeding territories, breeding territories are not exclusive and access to nectar is determined by distance to nest site. Such variability in spatial organisation is related to a continuum concept of social organisation.     

Producing Absolute Truth: CSI Science as Wishful Thinking

ABSTRACT  Forensic science has come to be assigned an important role in contemporary crime fiction. In this article, I analyze the cultural repertoire of forensic science conveyed by the popular television show Crime Scene Investigation (CSI). I argue that CSI science, in delivering an absolute "truth" about how and by whom crimes have been committed, is equated with justice, effectively superseding nonfictional forensic science as well as nonfictional judicature as a whole. Thus, CSI as a cultural performance adds to the mediascape a repertoire of wishful-thinking science with which to think about perceptions of and desires for crime and justice in nonfictional society. This repertoire seems to be considered relevant enough to nonfictional society to cause concern about the judicial system, as expressed in discussions of the so-called " CSI effect."     

The Innovative Materiality of Revitalization Movements: Lessons from the Pueblo Revolt of 1680

ABSTRACT  Although Wallace's revitalization movement model has been successfully utilized in scores of ethnographic and ethnohistorical studies of societies throughout the world, revitalization is considerably less well documented in archaeological contexts. An examination of the materiality of revitalization movements affords an opportunity to redress this lack by investigating how material culture creates and constrains revitalization phenomena. In this article, I reconsider the revitalization model through a case study focusing on the archaeology of the Pueblo Revolt of 1680, emphasizing the central role of materiality in the formation and mediation of these movements. In doing so, I examine the archaeological signatures of revitalization movements, concluding that they are highly negotiated and heterogeneous phenomena and that the materiality of these episodes cultivates cultural innovation. I also seek to demonstrate that the distinctive types of material culture produced through revitalization are not epiphenomenal but, rather, are crucially constitutive of revitalizing processes.     

Social network- and community-level influences on contraceptive use: evidence from rural Poland

The diffusion of ‘modern’ contraceptives—as a proxy for the spread of low-fertility norms—has long interested researchers wishing to understand global fertility decline. A fundamental question is how local cultural norms and other people''s behaviour influence the probability of contraceptive use, independent of women''s socioeconomic and life-history characteristics. However, few studies have combined data at individual, social network and community levels to simultaneously capture multiple levels of influence. Fewer still have tested if the same predictors matter for different contraceptive types. Here, we use new data from 22 high-fertility communities in Poland to compare predictors of the use of (i) any contraceptives—a proxy for the decision to control fertility—with those of (ii) ‘artificial’ contraceptives—a subset of more culturally taboo methods. We find that the contraceptive behaviour of friends and family is more influential than are women''s own characteristics and that community level characteristics additionally influence contraceptive use. Highly educated neighbours accelerate women''s contraceptive use overall, but not their artificial method use. Highly religious neighbours slow women''s artificial method use, but not their contraceptive use overall. Our results highlight different dimensions of sociocultural influence on contraceptive diffusion and suggest that these may be more influential than are individual characteristics. A comparative multilevel framework is needed to understand these dynamics.     

Flexibility and Repeatability of Finger Movements During Typing: Analysis of Multiple Degrees of Freedom

The kinematics of the hand and fingers were studied during various keystrokes in typing. These movements were defined by 17 degrees of freedom of motion, and methods were developed to identify simplifying strategies inthe execution of the task. Most of the analysis was restrictedto the 11 degrees of freedom of the fingers, neglecting thumband wrist motion. Temporal characteristics of the motion weredefined by computing principal components, and it was found thatonly a few (two to four) principal components were needed tocharacterize motion of each of the degrees of freedom.Hierarchical relationships among patterns within and betweendifferent degrees of freedom were identified using clusteranalysis. There was a considerable amount of consistency eachtime a given keystroke was executed by a subject, and thisrepeatability may imply a reduction in the number of degrees offreedom independently controlled by the nervous system. However,there also appears to be considerable flexibility in thecoordination of the many joints of the hand when examined acrossdifferent keys and across different subjects.