A multivariate distance nonlinear causality test based on partial distance correlation: a machine learning application to energy futures

This paper proposes a multivariate distance nonlinear causality test (MDNC) using the partial distance correlation in a time series framework. Partial distance correlation as an extension of the Brownian distance correlation calculates the distance correlation between random vectors X and Y controlling for a random vector Z. Our test can detect nonlinear lagged relationships between time series, and when integrated with machine learning methods it can improve the forecasting power. We apply our method as a feature selection procedure and combine it with the support vector machine and random forests algorithms to study the forecast of the main energy financial time series (oil, coal, and natural gas futures). It shows substantial improvement in forecasting the fuel energy time series in comparison to the classical Granger causality method in time series.     

辽宁东部水源涵养林计量指标体系及其效益评估

对辽东山区水源涵养林产生的各种效益进行计量评价研究,制定了水源涵养林计量效益评价指标体系,包括3级结构、16项指标、49项因子;依各功能因子的重要性并经测算,对各项指标赋予权重和排序,森林的蓄水、减少径流、改善水质功能的权重值较高;采用条件价值法,估算辽东山区水源涵养林的各种功能价值,森林的林副产品和木材收益的功能价值较高。辽东山区水源涵养林按整体处在一般经营状态下计算,年均创造功能价值约为30.2亿元。     

Natural resource accounting for Indian states — Illustrating the case of forest resources

Our main objective is to set out and apply a SEEA-based methodology to reflect the true value of forest resources in India's national and state accounts. We establish that a “top-down” approach using available national databases is both feasible and desirable from a policy perspective. In this paper, we address four components of value creation in forests: timber production, carbon storage, fuelwood usage, and the harvesting of non-timber forest products. The results of our analysis suggest that prevailing measures of national income in India underestimate the contribution of forests to income. The income accounts of the Northeastern states in particular are significantly understated by these traditional (GDP/GSDP) measures. We are also able to identify some states which performed poorly in the context of our sustainability framework, reflecting natural capital losses due to degradation and deforestation. Our results highlight the need to integrate natural resource accounting into the national accounting framework in order to generate appropriate signals for sustainable forest management and for the conservation of forest resources which are widely used by the poor in India, as well as being significant stores of national wealth.     

东西部地区之间公益林生态补偿负担与分摊

由于东部和西部地区之间自然和社会经济条件的差别，在公益林生态补偿问题上将会存在严重的地区之间生态建设责任与利益不平衡．因此需要建立地区之间的财政支付方式来平衡这种不公平状况．以利于公益林生态补偿制度的建立和完善。     

河南省林果业循环经济发展趋势

河南作为国家发改委确定的循环经济建设试点省份,近年来积极探索适合该省省情的循环经济发展模式,取得了一定成效,但同时也存在发展水平不高、区域发展不均衡等问题。文章就河南省林果业循环经济发展的优势、必要性、存在的问题及未来发展趋势进行简要的分析与探讨。该文指出了河南林果业循环经济发展面临的问题:一是林果业循环经济基础发展薄弱;二是循环经济相关法律有待完善,政府调节作用有待加强。对于未来河南林果业循环经济发展趋势,一是需要政府协调引导,形成发展合力;二是需要龙头企业带动,延长产业链条;三是需要农户积极参与,践行循环经济。让更多农户掌握生态林果栽培技术,将更多新技术与高效节能新装备与产品推广下去,促进林果业循环经济在更广阔的范围开展下去,让循环经济真正深入人心,实现河南林果业种植地区户户参与、人人参与的良好局面。     

生物质能源可利用潜力评价*——以黑龙江省重点国有林区为例

[目的]生物质能源具有污染少、可再生等特点,合理地对其开发利用是黑龙江省重点国有林区经济转型发展的一种探索。通过对黑龙江省重点国有林区生物质能源资源量的计算,明确了生物质能源的可利用潜力及变化趋势,以期为其产业发展的政策制定提供理论参考。[方法]文章利用自下而上估算法,以林木生物质的资源量和农作物秸秆的产量为原始数据,对2005—2015年黑龙江省重点国有林区生物质能源可利用潜力进行评价。[结果](1)研究期间,黑龙江省重点国有林区林木生物质资源可利用潜力小幅下降,农作物秸秆资源可利用潜力稳步上升。(2)林木生物质资源中,商品林采伐剩余物可利用潜力骤降,森林抚育剩余物可利用潜力增加;农作物秸秆资源中,粮食作物秸秆可利用潜力逐年上升。(3)黑龙江省重点国有林区生物质能源可利用潜力随着国家"天保工程"和"重点国有林区全面禁止天然林商业性采伐"政策的实施而发生变化。[结论]黑龙江省重点国有林区生物质能源丰富,可利用潜力较大,其中农作物秸秆资源可利用潜力增速较快。     

亚洲林业产权现状研究与分析

通过对国内外有关亚洲林业产权文献的回顾,对亚洲林业现状、林业产权的基本概念及亚洲林业产权进展情况进行了梳理与评述,在此基础上,从不同产权类型对森林资源的影响、产权的制约因素和产权制度变迁三个方面探讨了亚洲林业产权未来的发展趋势及前景。最后,建议我国今后在实施林权制度改革时应注意:加强授予权利的支持力度;加强林主的能力建设;提供充足的机构支持;分步实施改革。     

Sustainability and forest transitions in the southern Yucatán: The land architecture approach

Consistent with the challenges of sustainability science, land architecture offers a comprehensive approach to land system dynamics useful for numerous types of assessments, ranging from the vulnerability of coupled human–environment systems to forest transitions. With antecedents in several research communities, land architecture addresses the tradeoffs within and between the human and environmental subsystems of land systems in terms of the kind, magnitude, and pattern of land uses and covers. This approach is especially cogent for changes in tropical forests, given the broad-ranging forces acting on them and the equally broad-ranging consequences of their loss. The rudiments of the land architecture approach are illustrated for changes in seasonal tropical forests in the southern Yucatán of Mexico, the pivot of which is the Calakmul biosphere reserve. Simplifying the dynamics involved, the region-wide land architecture is the collective design of stakeholders with different land-use goals that favor tradeoffs in subsystem outcomes serving better either the reserve and related programs or the smallholder farmers that populate the region. A major tradeoff involves forest cover per se, which holds implications for forest transition theory. Evidence for an incipient transition involves the scale of analysis taken. The dynamics involved hold too much uncertainty to forecast a permanent transition to more forest cover and imply that more complex but robust versions of the theory are required.     

河北省林权制度演进的动因分析

河北省林权制度演进的动因主要包括国家意志的改变、农民需求的变化、人口数量的变化、森林资源稀缺程度的变化、要素和产品相对价格的变化等几个主要方面。以制度变迁理论、时间序列分析和供求理论对相应因素进行深入分析,结果显示:诸多动因相互作用推动了河北省林权制度的演进。因而,在制定林权政策时,要综合考虑各方面因素的影响以及相互之间的关系以期达到一个均衡状态。