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111.
曾永丰 《中国沙漠》2003,23(3):331-333
位于柴达木盆地南缘的诺木洪绿洲农牧业曾兴盛于约3300aBP,衰亡于约2900aBP之后的全新世晚期,诺木洪绿洲农牧业在这一发展过程中曾出现过一次间断。因此,可将晚全新世诺木洪绿洲农牧业的发展分为前后两期。全新世气候与环境的变化深刻地影响着盆地绿洲农牧业的出现、发展与衰亡。从诺木洪绿洲农牧业兴盛与衰亡史中可知,约于3300aBP在柴达木盆地就有了绿洲农牧业,而且盆地绿洲农牧业深受盆地环境变化的控制,干旱和沙漠化是盆地绿洲农牧业走向衰亡的直接原因。  相似文献   
112.
生物医学领域中许多工作对微计算机系统的要求常常是共同的。对信号应进行实时监视、记录、处理分析、存贮或输出。有些工作还要求系统给出触发信号,或能自动响应生物的行为反应。本文介绍一种生物医学微机测控系统的原理。作者研制的系统基于APPLE Ⅱ微机(已投入生产)和IBM PC,PC/XT微机,也容易转到其他计算机上。当然,该系统也可开拓应用到其他科技领域。  相似文献   
113.
Animal treading can change soil physical properties, and thus is an important factor in hydrological modelling. We investigated the impacts of animal treading on infiltration by using a series of rainfall simulation experiments at Whatawhata Research Center, Waikato, New Zealand. The study identified significant variables for estimating soil steady‐state infiltration at a micro‐site (0·5 m2) and fitted the Green and Ampt equation by modifying or including variables for soil and water parameters and animal activities on grazing paddocks. A regression function for estimating steady‐state infiltration rate was created for each of four scenarios: between tracks (inter‐track), track, easy slope with ash soil, and easy slope with clay soil. Significant variables included the number of days after treading, antecedent soil moisture, field capacity, percentage of bare ground, bulk density, and the high degree of soil damage (damage not compacted). Regression models explained more than 71% of the variance in steady‐state infiltration for three scenarios, but only 53% for the easy slope with clay soil. The remodified Green and Ampt equation provided satisfactory estimation of infiltration for all scenarios (accuracy > 80%), and thus enables us to use the modified model for Waikato hill country pastures of different topography, soil physical condition, season and grazing management. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
114.
New Zealand is an important place for thoroughbred breeding and racing. Most races are on the flat, but jumps racing is conducted in the cooler months. The 2013 National Jumps Day at Te Rapa, Hamilton, was a significant space for the construction of human–animal relations. Drawing on three bodies of accounts, we ask whether social media contributes to the realignment of perspectives or reinforces existing human–animal relations. We explore competing narratives and demonstrate how animals, people, activities and places are constructed, including making animal deaths unrecognisable to perpetuate activities that are questioned by contemporary animal geographies.  相似文献   
115.
观鲸旅游业在国外发展迅速,已成为尊重海洋动物权益、满足海洋旅游者“原真体验”需求的重要手段。本文对国外观鲸旅游的研究范畴和关注重点进行研究,力图为我国观鲸旅游业的健康发展提供经验借鉴和理论指导。目前国际观鲸旅游业的观赏对象以鲸目动物和鲸鲨为主,侧重于对观鲸旅游活动开展对海洋生物习性、行为模式的影响研究,在经营管理方面的研究侧重依观鲸旅游业开展的成熟与否而有所差别。  相似文献   
116.
吉林省土壤动物组成与生态分布的初步研究   总被引:7,自引:0,他引:7  
孙帆  刘震 《地理学报》1991,46(3):300-318
1989年6—8月,作者对吉林省九种景观类型的土壤动物进行了调查,共获土壤动物111类、22653只,分隶于6门、13纲、23目、72科。从总体上看,土壤动物类群数和个体数是森林环境高,而草原、沙地环境低。通过聚类分析,将大型土壤动物归为五类,中小型土壤动物归为四类。土壤动物的类群数和个体数随土壤深度的增加而递减。本文还探讨了五种主要土壤动物的分布特点。  相似文献   
117.
Michael Campbell 《Area》2009,41(2):139-148
Animal behaviour is vital for livestock choices, but is less researched in West Africa than economic considerations. An animal geography framework is applied to the socio-economic context of livestock behaviour in coastal Ghana, assessing the shared 'actant' behaviour of people and animals, and the contribution of such a study to animal geography and agricultural knowledge. Data were gathered on cattle, sheep and goat behaviour and the impact of these on human livelihoods, perceptions and the socio-environmental context. Animal behaviour was more important in the choice of livestock species, but economic considerations were more important in the decision to acquire animals. Goats had more incidents with people in village centres than sheep and cattle. Cattle had more incidents in farmland and grassland than goats and sheep. Women and young people were more affected by livestock behaviour. These findings increase the understanding of livestock zoogeography and livelihood decisionmaking, and contribute to animal geography by documenting the relevance of individualised gender- and age-based human behaviour, as well as intra- and inter-species animal behaviour to a shared actancy perspective, and a more dynamic zoogeography.  相似文献   
118.
西双版纳不同山地长果桑及食果动物   总被引:3,自引:0,他引:3  
热带雨林是大自然赋予人类的珍贵资源宝库 ,有着久远的发展历史 ;认识其间的动植物关系以及人类影响下的动态变化 ,不仅有重要学术意义 ,而且对热带山地生态系统的保护、恢复 ,山区的持续发展有现实指导作用。我们在长果桑果期研究了西双版纳不同强度人为影响的热带山林摄食动物种群结构 ,对地区的发展和热带山地生态系统的维护有了新的认识。  相似文献   
119.
Due to increasing anthropogenic habitat alteration, fragmentation, and loss, the analysis of how, when, and why animals select particular habitats has become a central issue in ecology and biogeography. Animals adapt to spatiotemporal variability in resources either by tracking these resources or by plasticity in behavior to cover their needs, leading to three important implications: movement, temporal variation, and individual trade-offs leading to intra-species variability, all of which are directly linked to the use of space by animals. Based on GPS-tracking of domesticated reindeer in southern Norway, the authors addressed these issues by analyzing movement patterns and space use simultaneously across different temporal and organizational scales. Emerging information about the space use by reindeer was found explicitly linked to scaling relations, reflecting the matter of scale as having important functional implications rather than solely being a technical question of extent and resolution. Adding movement into the analysis of space use further advances the necessary functional perspective on space use. The authors conclude that scaling not only space but also time and the organizational level, in combination with accounting for different behavioral states, brings biogeography closer to a process-based view, rather than solely pattern-based view.  相似文献   
120.
针对“定居兴牧”水源工程勘测设计、建设管理中的难点问题和关键环节,分析和阐述了立项审批、建设资金、建设管理及质量安全三项保障措施,以及建立的坝工建设、工程水文计算及工程地质勘察、工程设计与施工技术体系三项技术支撑,提出了工程规模“择小放大”、泄水建筑物规模“择大放小”、抗震设计“评Ⅶ设Ⅷ”、灌溉模式“择高有压”、地质条件复杂“避让放弃”等技术措施和应把握的原则,建立了“定居兴牧”水源工程技术支撑体系;并针对牧民定居水资源保障和安置模式、水源工程水价及管理、受水区开发规模等问题进行了分析讨论,指出新疆已不具备大规模开发水土资源的条件,采取“集中定居、插花定居、分流转产”三种定居模式,是切合新疆实际的;水源及其配套工程效益的发挥,需要加快饲草饲料基地开发建设,走集约化、现代化发展之路;水价应考虑牧民承受能力和工程良性运行的需要,可采取财政扶持、分阶段逐步到位,实施定居区水务一体化管理,发挥项目的规模效应;定居区规模要做到“水土平衡、供需平衡”,防止“小马拉大车”;工程建成后,要加强水文监测,为水库安全度汛和调度提供可靠的基础依据.定居兴牧水源工程的顺利实施,赋予了“新疆效率”深刻的科学内涵,对于加速现代草原生态畜牧业发展,具有一定的借鉴、指导作用.  相似文献   
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