Acacia exchanges: Wattles, thorn trees, and the study of plant movements     

Christian A. Kull  Haripriya Rangan   《Geoforum》2008,39(3):1258-1272

Plants are frequently moved around the world, creating new regional landscapes and environmental imaginaries. Building on previous work in environmental history and geography, we develop a three-part approach to analyzing plant movements and apply it to trees from the Acacia genus (sens. lat.) exchanged between Australia and the rest of the world. First, we investigate the agents, circuits, and frequencies of acacia movements, including transoceanic transfers, regional diffusion, and ecological dispersal. Second, we trace bundles of knowledge or technology that accompany the acacias, highlighting how they help shape regional biogeographies. Finally, we analyze how different societies, with distinct economies, politics, and environmental sensibilities, receive introduced plants. This approach allows us to see transferred plants as active agents in region-forming processes, and to avoid normative tropes like ‘miracle plants’ or ‘alien invasives’. The highlighted species include Acacia colei, Acacia melanoxylon, Acacia mearnsii, Acacia farnesiana, Acacia nilotica, Acacia mangium, and their close relatives.  相似文献   

Hierarchical Bayesian spatial models for predicting multiple forest variables using waveform LiDAR,hyperspectral imagery,and large inventory datasets     

《International Journal of Applied Earth Observation and Geoinformation》2013

In this paper we detail a multivariate spatial regression model that couples LiDAR, hyperspectral and forest inventory data to predict forest outcome variables at a high spatial resolution. The proposed model is used to analyze forest inventory data collected on the US Forest Service Penobscot Experimental Forest (PEF), ME, USA. In addition to helping meet the regression model's assumptions, results from the PEF analysis suggest that the addition of multivariate spatial random effects improves model fit and predictive ability, compared with two commonly applied modeling approaches. This improvement results from explicitly modeling the covariation among forest outcome variables and spatial dependence among observations through the random effects. Direct application of such multivariate models to even moderately large datasets is often computationally infeasible because of cubic order matrix algorithms involved in estimation. We apply a spatial dimension reduction technique to help overcome this computational hurdle without sacrificing richness in modeling.  相似文献   

Making a difference: Forest biodiversity,affective capacities,and the micro-politics of expert fieldwork     

《Geoforum》2015

Protecting biodiversity requires the practice of making nature values present in natural resource use decisions. In this article, such practices are explored from the perspective of affective capacities for expert fieldwork in forestry. Affective capacities are broadly acknowledged in the literature on embodied knowing, and by the practitioners themselves, as a necessary condition for knowing nature. We will extend this discussion to the politics involved. Drawing on a case study in Finland, the article points out that professional foresters’ affective ways of knowing nature are controlled by institutionalised strategies and practices. Thus, power is exercised through fieldwork, determining how nature can and should be known in forestry. The article concludes that since policy implementation takes place through the intensities present in mundane routines, governance studies would benefit from understanding how the various technologies of governance interact with emergent and embodied capacities.  相似文献   

西南农业的展望     

程鸿 《云南地理环境研究》1989,1(2):27-33

西南人口占全国五分之一,其农业情况,不仅关系到当地人民的生活与经济发展的前景,而且也关系到国家全局。近年来,西南农业发展缓慢,粮食短缺,形势严峻。本文着重讨论了西南农业发展中的四个主要问题:1.加强农田基本建设,提高耕地生产力,为粮食和其他农作物的大幅度增产打好基础。2.由于人口增长,粮食产需矛盾不断加深,增产任务艰巨,必须引起高度重视。排除干扰,及时采取切实措施,保证实现各省区不同水平的生产目标。3.进一步巩固和发挥经济作物、畜产品和生物资源的区域优势。4.把西南建成为国家强大的后续林业基地,改善环境质量,增产各种林产品。  相似文献   

基于C/S与B/S混合体系结构的林业管护经营监控系统的设计   总被引：1，自引：0，他引：1  

张庆全  余迎 《测绘与空间地理信息》2009,32(1)

对C/S,B/S两种软件体系结构进行了分析比较,论述了林业管护经营监控系统是一个大型的、复杂的监控系统,针对不同的用户,采取合理的软件体系结构设计,将会使该系统具有更好的应用前景.提出了基于C/S与B/S混合体系的林业管护经营监控系统的设计框架,包括其实现的主要功能、体系结构、安全策略、数据备份与恢复等关键技术.  相似文献   

The effect of forestry drainage operations on upland sediment yields: A case study     

M. Robinson  K. Blyth 《地球表面变化过程与地形》1982,7(1):85-90

Forestry is generally considered to be a land use giving low sediment yields. However, in Britain most forestry is on land that requires extensive drainage, and it was found that the drainage of a small upland catchment resulted in sediment yields over the following five years equivalent to nearly half a century's load at pre-drainage rates. Subsequent sediment yields did not decline to pre-drainage levels, but remained about four times higher, as a result of erosion of the drains.  相似文献   

On modelling the effects of afforestation on acidification in heterogeneous catchments at different spatial and temporal scales     

A. J. Wade  C. Neal  C. Soulsby  S. J. Langan  R. P. Smart 《Journal of Hydrology》2001,250(1-4):149-169

A modelling approach is presented for simulating and predicting future changes in streamwater Gran alkalinity throughout a large, heterogeneous river system. The methodology is based on integrating End Member Mixing Analysis (EMMA), the Model of Acidification of Groundwater in Catchments (MAGIC) and spatial data describing the catchment characteristics stored on a Geographical Information System (GIS). These are integrated within a Functional Unit Network (FUN) to predict the changes in Gran alkalinity resulting from possible future changes in atmospheric deposition and land use (low intensity afforestation) in the River Dee catchment, NE Scotland. Model results indicate that declining sulphate and constant nitrogen deposition, combined with low intensity Scots pine (Pinus sylvestris) afforestation are unlikely to contribute significantly to streamwater acidification.  相似文献   

论西藏的天然林保护与林业可持续发展   总被引：1，自引：0，他引：1  

罗大庆  薛会英  边多 《山地学报》2001,(Z1)

从西藏的天然林资源和林业经营现状 ,概述了天然林资源在可持续发展战略中的地位和作用 ,资源过度消耗引发的生态环境问题 ,以及实施天然林保护工程的重大意义和西藏林业实行分类经营的基本恩路及对策。  相似文献   

科技支撑在安徽省林业血防工程建设中的作用与地位     

骆绪美  丁常慧  赵学诗  肖正东  方建民  吴中能 《湿地科学与管理》2010,6(3):4-7

在简述林业与血防建设关系的基础上,强调了林业血防工程的重要性,着重论述了科技支撑对林业血防工程建设的推动、技术保障、引导和示范作用。总结了安徽省林业血防工程的成效,充分体现科技支撑在林业血防建设中的主导地位。  相似文献   

大兴安岭阿龙山地区花岗片麻岩的同位素年龄与超大陆   总被引：1，自引：0，他引：1  

赵海滨韩振哲  刘旭光 《华东地质学院学报》2005,28(4):313-316

阿龙山花岗质片麻岩是在阿龙山镇幅1：25万区调过程中从兴华渡口岩群变质杂体中解体出的古花岗质侵入体。阿龙山地区的花岗片麻岩的锆石U-Pb年龄的测定结果表明，其原岩形成时代为1100Ma左右，在565Ma曾受到高温变质作用。两组年龄的获得为大兴安岭地区早期大陆裂解及碰撞造山作用的确定提供了直接证据，这一结果表明额尔古纳微陆块曾经历了格林威尔期和罗丁尼亚超大陆的聚合、裂解和冈瓦纳泛大陆的再造的多次开合作用。  相似文献