Public Investment and Environmental Sustainability of Agricultural Production in China

The excessive application of fertilizer and pesticides in grain production in China has posed a threat to the environmental sustainability of agricultural production. One of the major reasons of the increasing usage of chemical inputs by farmers is their trying to reach higher yields, especially in absence of adequate public inputs, such as development and extension of appropriate technology and necessary production infrastructure, etc. Based on the crop specific data of the past 20 years, this paper examines how the public investments in agricultural researches could impact on the reduction of farmers' private material inputs of major grain crops in China. It manifests that the increased investments in public sector, especially in agricultural researches, is a favorable and effective way to reduce farmers' private material inputs and should be given a priority consideration in the policy emendation to increase yields and improve production sustainability.     

SUBSCRIPTION INFORMATION

<正>Chinese Journal of Population Resources and Environment,Print ISSN 1004-2857,Online ISSN 2325-4262,Volume 11,2013.Chinese Journal of Population Resources and Environment(www.tandfonline.com/tpre)is a peer-reviewed journal published in March,June,September,and December by TaylorFrancis,4 Park Square,Milton Park,Abingdon,Oxon,OX14 4RN,UK.     

Flood Protection: Highlighting an Investment Trap Between Built and Natural Capital

We present a simulation model developed to communicate a potential investment trap associated with using man‐made river engineering to protect built infrastructure. A small system dynamics model in STELLA? was constructed following a collaborative model‐building process to increase understanding among stakeholders of the role natural capital plays in wealth creation. We set out to explore the dynamic relationship between investing tax revenue in natural capital (specifically forested headwaters and low land wetlands) rather than built capital (specifically stopbanks) for flood protection in the Manawatū watershed, New Zealand. Significant investment is currently required to maintain and enhance river engineering infrastructure and keep pace with changes in the river's geomorphology. Viewed from a systems perspective, we suggest diversion of a proportion of existing funding into restoration of forested headwaters on steep slopes and restoration of functioning wetlands on floodplains could in the longer term provide an effective approach to flood protection. Co‐benefits of increased natural capital include the ecosystem services nutrient cycling, sediment capture, water purification, biodiversity, pollination, and cultural and recreational values. Overcoming an investment trap requires a longer term perspective. This simple model consisting of two feedback loops and two delays aims to contribute to an ongoing stakeholder dialogue concerning the Manawatū River watershed in New Zealand.     

土地复垦投资机制及其制度

本文借鉴国外土地复垦投资的经验 ,总结我国土地复垦投资实践以及我们的研究成果 ,提出土地复垦投资机制的基本思想以及与其相适应的主要制度 ,为土地复垦投资服务     

Function of the mating plug in Drosophila hibisci Bock

The mating plug in Drosophila hibisci Bock is a firm, gelatinous structure that forms within the female’s uterus during copulation. Two non-mutually exclusive hypotheses for the function of the plug were evaluated. The plug may serve as a nutritional gift that females digest, using the constituents for somatic maintenance or to provision eggs as they mature within the ovaries. Alternatively, the plug may act as a chastity enforcement device by preventing subsequent copulations, and thereby reducing sperm competition. Plug size did not decrease within females over a period of 2 days, and dietary treatment in females did not affect plug size. The extent of ovarian provisioning was also not related to plug size. These results weaken the nutritional gift hypothesis. In contrast, the probability of a second copulation increased sharply with an experimental decrease in plug size. Moreover, females with plugs experimentally reduced in size were courted significantly more and mated significantly faster than females with larger plugs. These results support the chastity enforcement hypothesis. The plug retains the ejaculate and concentrates sperm at the anterior end of the uterus near the apertures of the sperm storage organs. The presence of the plug thus probably facilitates the movement of sperm into storage by retaining sperm at the anterior end of the uterus near the apertures of the sperm storage organs, which may be especially important for D. hibisci, in which sperm length is nearly twofold greater than ventral receptacle length. Matings with newly eclosed virgin females were significantly shorter than with older virgins, and copulations with the younger virgins ended more often without any sperm having yet entered into storage. The effectiveness of the plug in safeguarding a male’s ejaculate may have favoured the evolution of shortened copula durations with young virgins. One fitness advantage of shortened copula duration could be time liberated for the pursuit of further mating opportunities. Received: 12 May 2000 / Revised: 22 September 2000 / Accepted: 15 October 2000     

Technology transfer

A currently fashionable method of industrial diversification is ‘technology transfer’. The paper discusses the new mood of positive thinking within Scottish industry, and the role of the Scottish Development Agency's Technology Transfer Division in responding to the approaches received for specialist support. The author concludes that technology can have a major impact on many of the variables which contribute to the performance of a regional economy.     

模糊灰色关联法在分析安全投资因素与效益关系中的应用

灰色关联分析法存在分辨系数的选取主观性较大,比较序列曲线空间位置不同以及因素权重归一化而影响关联度,取平均值求关联度影响评价准确性等缺点。笔者采用线性变换及合理判定分辨系数的方法,确定了改进的关联系数,提出了改进的灰色关联分析法。在明确安全投资的基本内涵及构成的基础上,运用该法可计算出来影响安全投资效益因素的灰色关联度,以进行分析,找出企业安全投资合理的方向,从而可以提高企业安全投资的效益。实例分析表明,该法简便实用,可靠准确,对分析安全投资效益影响因素有较好适用性。     

民窿空区群级联失稳评价

民窿空区群已构成了许多矿山安全生产的极大隐患。针对民窿空区群的特点，运用重整化群方法，从整体的角度对民窿空区群系统的稳定性问题进行了研究，得到了空区群变尺度级联失稳迭代函数。给出了判别空区群系统整体失稳的临界概率，将空区群系统失稳的复杂判别转化为单元失稳概率与临界概率大小的比较问题，同时给出了计算实例，以供参考。所建立的方法可以为大规模民窿空区群范围内的工程施工以及民窿所在矿山空区群整体稳定性评价提供参考，同时也为认识一般空区群系统的失稳机理开辟了一条新的途径。     

我国现阶段城市污水处理领域投融资机制问题分析

本文在分析了我国城市污水处理设施建设投融资机制的发展历程和挑战的基础上,提出了在现阶段需要解决的问题,并重点研究了如何为污水处理领域的私人部门参与项目提供资金支持,并保证公平受益以及要根据区域特征明确投融资和污水处理费的政策导向。     

Enhancing climate technology transfer through greater public–private cooperation: Lessons from Thailand and the Philippines

This article contributes to debates about climate change policy and technology transfer by analyzing the success factors underlying collaboration between private companies and communities in developing countries. To date, much attention to capacity building for enabling environments — including public–private collaboration — under the climate change convention has focused on state‐led initiatives and on the innovation and development of technologies. This article, instead, focuses on how private‐sector investors and host communities may collaborate in the diffusion of technologies, by reducing the costs of technology transfer, and making technology more appropriate to developing countries. The article describes cases of collaboration concerning waste management and waste‐to‐energy in Thailand and the Philippines. The article argues that successful public–private partnerships between investors and communities depends on minimizing transaction costs, strengthening collaborative (or assurance) mechanisms, and in maximizing public trust and accountability of partnerships. Lessons are then drawn for enhancing capacity building for technology transfer under the climate change convention and applications such as the Clean Development Mechanism.