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41.
Over the last two decades there have been significant and well‐documented changes in the nature and structure of New Zealand dairy production. One particular feature has been a marked shift in the ‘input intensity’ of dairy farming systems through increased use of supplementary feed. These changes have generated debate about the impact of dairy farm intensity on the performance of farm businesses and the competitiveness of the New Zealand dairy sector. Using a novel econometric approach, we assess statistically the impact of three types of dairy farming systems on milk production and financial performance, using farm business data provided by DairyBase®. Our empirical results show that higher input systems perform significantly better physically than lower input systems, but not financially. The disaggregated analysis suggests that the average treatment effects differ by region and performance quantiles.  相似文献   
42.
研究目的:探讨不同规模农户采纳秸秆还田技术的行为差异和影响因素。研究方法:采用Logistic模型对冀、鲁、皖、鄂4省1372份农户调查数据进行实证分析。研究结果:(1)农户的秸秆还田技术采纳行为存在规模经济效应;(2)地块数和区位条件是限制小规模农户采纳秸秆还田技术的客观因素,在土地规模短期不能扩大的情况下,秸秆还田技术不具备普适性是该项技术推广受阻的重要原因;(3)配备秸秆还田服务人员机构,有针对性地对小规模男性农户进行培训和指导,提高农户的经济收入和经济感知,能显著促进小规模农户采纳秸秆还田技术。研究结论:应从改善机械作业条件,促进土地适度规模经营;改进秸秆还田技术,降低技术采纳成本;培育秸秆还田社会化服务组织,提高农户认知等方面着手,有效推广秸秆还田的耕作技术手段。  相似文献   
43.
During the past 15 years, there has been a considerable increase in highland maize farming in Nan, a province in northern Thailand. The increase in farming area causes an excessive forest encroachment and environmental problems, e.g. soil degradation, landslide, and pesticide contamination. This research explores the mechanism and factors which drive a sustainable transformation from highland maize farming to reforestation. We survey 107 farmers in Nammeed and Sopsai watersheds in where the reverses of growing trend of deforestation in Thailand have been observed. Comparative statistical analysis and regression are used to analyse factors affecting farmer’s decisions and compare differences between the two sites. We find that the fundamental mechanism driving a sustainable transformation from highland maize farming to reforestation comprises 3 pillars. These are 1) realization of adequate economic, health or environmental benefits derived from the alternatives; 2) a sense of belonging and attachment towards the forest and 3) effective enforcements of communal rules and regulations. While natural transformation in Nammeed area highlights the roles of flatland as key driver of the change, subsidy schemes can supplement the transformation during transitional period as seen in Sopsai area.  相似文献   
44.
This paper examines relationships between crop insurance and input technology decisions among Chilean wheat farmers. Using nationwide farm‐level data, a bivariate probit model is estimated. We investigate the extent to which the adoption of production input technologies is associated with farmers’ participation in the insurance program. We find that relationships between insurance and technology decisions are significant only for family farmers. In particular, there is a negative relationship between participation in the insurance program and the adoption of modern irrigation. Interpretations based on the role of input technologies on insurance adoption and adverse selection behaviours are discussed.  相似文献   
45.
South Africa's sugar industry has long been distinguished by its large number of small‐scale sugarcane growers (SSGs) farming on ‘communal’ land and its peculiar privately administered regulatory structure. In recent years, however, the numbers of small‐scale growers have declined precipitously. This paper argues that the relationship between the rise and fall of SSG production and the industry's governing regulatory structure is closer than usually appreciated. The emergence of SSG production in the late 1970s and the 1980s can be traced to industry‐subsidized initiatives, disguised as small‐scale credit, to bring commercially inalienable Bantustan land into cane production with strong miller oversight. From the late 1980s to 1990s, however, the elimination of these subsidies encouraged millers to subcontract support to farmers, while simultaneously instigating an increase in SSG numbers by removing restrictions on grower registration. Although low rainfall is a central proximal factor in the rapid decline of the SSGs in the 2000s, their rapid increase was structurally fragile.  相似文献   
46.
王鹏  邵睿  曾珍 《价值工程》2022,41(9):77-80
干冰技术的去污效率高、基材损伤小、二次废物量少,在核设施的去污实践中越来越多的受到重视。由于核电站反应堆换料系统的去污比较常见,通过对反应堆换料水池、乏燃料贮存运输容器的去污需求分析,设计一套干冰去污装置,实现对核设施的有效去污,满足人员操作和设备运输的要求;其去污过程和最终二次废物产量也遵循了废物最小化的原则,且环保高效,是未来放射性去污的重要发展方向。  相似文献   
47.
干法烟气脱硫渣在建材行业中高技术附加值利用的探讨   总被引:1,自引:0,他引:1  
文章阐述了目前国内外对干法脱硫渣综合利用的现状,以胶凝材料学以及水泥化学为理论基础,将干法脱硫渣中的物质划分为三类,并提出在充分激发其活性的基础上,对干法脱硫渣进行高技术附加值的利用,并详细阐述了其原理和途径。  相似文献   
48.
在GIS的支持下,选定东北后备农用地资源利用的影响因子,通过GIS的权重叠加模型运算,对东北地区后备农用地资源进行耕地适宜性评价,对于开发、利用和保护东北地区土地资源具有一定的实际意义。  相似文献   
49.
In this paper, we link three theoretical perspectives – organizational knowledge, ecological knowledge and social–ecological systems – to derive new conceptions of multi‐disciplinary, multi‐tier, sustainability‐oriented knowledge. Our study examines how collaboration between pasta‐producer Barilla, the farmers/smallholders supplying the firm and scientists generated sustainability practices in the agri‐food industry by creating transformative ecological, technical and scientific knowledge. In 2010, Barilla initiated a sustainable farming project to significantly reduce the environmental impact of cultivating durum wheat, its most important raw material. Core components included replacing monoculture with crop rotation, collectively creating innovative approaches that support farmers’ decision making and generating widely accessible guidelines for sustainability‐oriented cropping knowledge and practices. These collaborative efforts initiated profound transformations within and beyond the organization's boundaries via increased production yields, reduced environmental impacts and improved sustainability of farming practices, which generated economic, social and ecological benefits for farmers, surrounding communities and the firm. Copyright © 2016 John Wiley & Sons, Ltd and ERP Environment  相似文献   
50.
干挂石材幕墙是建筑幕墙的一种类型,近年来在国内高层建筑外墙装修中得到广泛应用。结合工程实例,文章从安全施工原则出发,通过对干挂石材幕墙的构造、结构设计、主要材料的选用及其施工工艺等环节进行论述,阐述了干挂石材幕墙深化设计过程。  相似文献   
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