马尾松脂材两用人工林经济效益分析与评价——以广西国有派阳山林场为例

采用项目投资的财务效益评估手段,以脂材两用经营模式16a生马尾松采脂林为对象,对其经济效益进行了分析评价。结果表明:在该经营模式下,采脂林分总产值、净收益、净现值(NPV)、内部收益率(IRR)分别为147 173.1元.hm-2、85556.9元.hm-2、15 587.7元.hm-2、37%,比未采脂林分提高194.5%、214.1%、342%、76.2%;采脂林分动态投资回收期为10.6a,比未采脂林分缩短4.8a。运用该模式经营马尾松人工林能获得极高的经济收益和在较短时间内收回投资成本,提高资金的利用效率。     

湿地松早期采脂的效益评价

湿地松早期生长迅速,如何使湿地松最快地产生经济效益就显得十分重要。本试验通过对广西环江毛南族自治县华山林场5年生湿地松人工林进行采脂试验,结果表明:湿地松早期采脂经济效益显著,具有较高的获利能力,采脂林分NPV(16 089.13)、IRR(39.2%)均远高于未采脂林分NPV(-3 165.91)、IRR(-2.2%)。同时可带来相当可观的劳动力需求,具有良好的社会效益。采脂对湿地松的生长有一定的影响,松脂产量与其胸径相关紧密。     

人工林地力衰退及防止对策

众所周知,森工企业的可采森林资源,急剧减少,为解决这个问题,加快了人工林发展步伐,特别是加大了速生丰产林营造比重.但是,随着人工林增加,地力衰退也就日益明显.当前如何持久地维持人工林高的生产力,防止地力衰退,已成为林业界普遍关切的问题.据绥棱林业局调查,1970年营造的落叶松人工林,生长率由幼龄林时期的22.9%,锐减到5.6%,公顷生长量仅在5—6m之间.据东北林业大学造林研究所调查结果表明,北方营造的长白落叶松人工林、地力下降明显,在好、中、差三种立地类上,林分平均高的下降速率依次为12.7%、23.3%和29.0%.人工林地力衰退,不单单是技术性问题,很大程度是管理上的原因.     

福建省国有林场营林投资经济效益评价研究

运用净现值法和内部收益率法,用福建省国有林场杉木生产过程中发生所有费用和木材生产过程中发生费用的资料,研究福建省国有林场营林投资经济效益。结果表明:国有林场林业投资有一定的经济效益,但经济效益还是比较低;以6%的资本利率,杉木投资的净现值为178.53元/hm2。林业税费政策调整以后,林业投资收益主要取决于造林抚育的支出水平。     

杉木人工林经济成熟龄的研究

利用杉木人工林标准地材料建立生长收获预估模型,根据技术经济指标采用净现值法研究经济成熟。结果表明:在现有技术经济指标的情况下,利率为5%时杉木人工林经济成熟龄为17年。若其它条件保持不变,木材价格或成本每增减20%,杉木人工林经济成熟龄将推迟或提前1年。利率对经济成熟龄的到来有显著影响,利率每增加1个百分点,经济成熟龄将提前1年。     

高脂松开发与速丰栽培技术

高脂松是优良的采脂、纸浆、纤维板、胶合板、建筑材、家具材树种,特别是松脂,应用广泛,有广阔的市场前景。高脂松种后5～8a成材,8a开始采脂,采脂年限达15a,1个轮作每公顷收益达120万元;生态、社会效益好。本文总结相应的栽培技术,供广大栽培者参考。     

林业投资模式的探讨

湖南省自1990年启动实施世行贷款国家造林项目,经过7年各方的共同努力,至1997年底已圆满完成项目建设任务。根据项目竣工验收报告：累计完成项目造林面积11．9万公顷,累计完成项目投资33783．6万元。其中提取世行信贷资金折合人民币19127．9万元,省内各级配套14655．7万元。预计项目经营期内,可获木材19181万m3,松脂3．91万吨,薪材641万m3,总产值达111．2亿元;可实现利润44．7亿元。经预测还本付息和上交税费后,财务内部收益率仍达14．15％,财务净现值（i＝12％）1．32亿元;项目经济内部收益率为22．61％,经济净现值（i＝12％…     

基于动态财务评价的土地综合整治项目投资决策

该文以成都市温江区土地综合整治项目为例,采用动态财务评价法,选取财务净现值、财务内部收益率、投资回收期三项指标对其现金流量进行分析.结果表明,温江区土地综合整治项目财务净现值为0.09亿元,财务内部收益率为18％,投资回收期为9年,项目经济可行性较好;节约的建设用地指标出让收益约占总收益的84.85％;项目对地上附着物补偿费和城镇建设用地指标出让最敏感.     

碳汇目标下竹林经营经济效益评价与差异分析

基于《竹林经营碳汇项目方法学》和实地调研数据,构建新的项目经济效益评价模型,对遂昌县竹林经营碳汇项目进行经济效益定量评估,并分析不同经营目标和不同经营措施下竹林经营碳汇项目净现值的差异及影响因素。结果表明:遂昌县在30年竹林经营碳汇项目运行周期内的净现值为8.63亿元,相比于传统经营提高了98.29%;在基线水平下,以碳汇经营为目标提高林分胸径的经营措施更有利于提高经济效益;影响竹林经营碳汇项目净现值的重要因素敏感程度从大到小依次为竹材价格、劳动力价格、竹笋价格、碳汇价格。最后,为实现森林增汇目标从加强碳汇项目宣传和提高林农经营技术等方面提出了相关建议。     

核桃种植的经济效益分析——以云南省大姚县为例

采用2010-2017年有关云南省各州市及大姚县各乡镇核桃种植情况的统计数据,从大姚县核桃产业的分布区域与产量角度对其现状进行分析,同时采用静态分析和动态分析相结合的方法对大姚县核桃种植的经济效益进行了重点评价和分析。计算结果表明,种植核桃20年的累计净现值为159 255元/hm2,投资收益率为56.6%,远远高于12%的基准折现率,年平均利润为35 156元/hm~2,核桃的静态投资回收期为13.93年,投资回收期相对较长。对此分析大姚县核桃种植中需解决的问题,提出了相应的政策建议。     

意愿调查评估法在生物多样性非使用价值评估中的应用——以辽宁老秃顶子自然保护区为例

运用意愿调查评估法(CVM),以随机抽样方式对辽宁老秃顶子自然保护区周边区域320名居民进行问卷调查,得到辽宁老秃顶子自然保护区的生物多样性非使用价值平均支付意愿(WTP)为44.45元·人-1,非使用价值总额为4.30×108元·a-1,其中存在价值、遗产价值和选择价值分别为2.33×108元·a-1、1.27×108元·a-1和0.70×108元·a-1。被调查居民的收入水平和对保护区的偏爱程度与支付意愿具有显著相关性,而性别、职业和文化程度则与支付意愿不相关。     

A Real Options Approach for the Investment Decisions of a Farm‐Based Anaerobic Digester

The profitability of anaerobic digesters (ADs) for Ontario dairy farmers are examined using real options under current and proposed government pricing policies and investment uncertainty. In the case of a renewable energy initiative such as an AD with large sunk costs and volatile returns, the value of deferring investment may be significant enough to offset the returns suggested by the net present value (NPV) approach. For a 150 cow herd, net revenues should be approximately $1.1 million before the AD is installed using the real options approach as compared to $0.5 million with the NPV approach. An AD is close to generating a positive NPV for a 600 cow herd if for either a 1% increase in the electrical price or decrease in the cost. However, farmers need not invest today and there is a value to delaying this decision from potential improvements in the technology that increase the efficiency and/or decrease operating costs of the AD. The real options analysis indicates that this option to delay investment has a value of approximately $300,000 for a typical Ontario dairy farm. Thus, either significant grant funding or higher feed‐in‐tariff rates are required to induce the increased adoption of AD technology in Ontario today even for the largest of dairy farms. Considering the probability of government support potentially ending, increases the value of investing today but a significant option value to defer still exists.     

The economic impact of productivity maintenance research: breeding for leaf rust resistance in modern wheat⋆

This paper reports the results of a study undertaken to estimate the economic impact in developing countries of efforts by the International Maize and Wheat Improvement Center (CIMMYT) to breed leaf rust resistant spring bread wheat varieties since 1973. The challenge in estimating these benefits lies in the pathogen's ability to mutate to new races, which may infect previously resistant varieties. Genetic resistance, rather than fungicide application, is the principal means of controlling leaf rust in developing countries. Whereas productivity enhancement is often estimated in terms of yield gains and increased supply, productivity maintenance is measured in terms of the yield losses avoided by the research investment. The internal rate of return on CIMMYT's research investment was estimated at 41%. When discounted by 5%, the net present value was US$ 5.36 billion in 1990 dollars, and the benefit‐cost ratio was 27:l. These findings emphasise the economic importance of maintenance research in crop breeding programs.     

全国苹果种植收益波动特征及其影响因素分析——基于1991～2014年苹果种植收益数据的实证分析

[目的]文章依据1991~2014年全国苹果种植成本收益的年度数据,在对苹果种植收益波动特征进行描述性分析的基础上,选取苹果单位面积净收益、 单位面积物质与服务费用、 单位面积产量和单位产品出售价格这些变量来研究对苹果种植收益的影响.[方法]通过构建VAR模型,并运用脉冲响应函数和方差分解来分析苹果种植收益的影响因素.[结果]苹果种植产值和净收益总体上呈上升的态势,成本利润率呈现出M型的波动趋向.苹果种植净利润的增长主要得益于产值的增加高于总成本的增加,而产值的增加又得益于苹果单产的提高和出售价格的上涨.单位产品出售价格对苹果种植净收益的影响最大,其次是单位面积产量和单位面积物质与服务费用.[结论]完善苹果价格形成机制,逐步实现苹果定价机制的市场化和定价水平的合理化;增强农业基础设施建设的投入,加强苹果种植综合生产的能力;抑制农资成本和价格的过快增长,降低种植成本是增加苹果种植净收益的重要手段.     

A model of entry–exit decisions and capacity choice under demand uncertainty

Many investment decisions of agribusiness firms, such as when to invest in an emerging market or whether to expand the capacity of the firm, involve irreversible investment and uncertainty about demand, cost or competition. This paper uses an option‐value model to examine the factors affecting an agribusiness firm's decision whether and how much to invest in an emerging market under demand uncertainty. Demand uncertainty and irreversibility of investment make investment less desirable than the net present value (NPV) rule indicates. The inactive firm is more reluctant to enter the market when it takes into account demand uncertainty because it preserves the opportunity of making a better investment later. The active firm is more reluctant to abandon the investment because there is an option value of keeping the operation alive. There is a greater distance between the entry and exit thresholds under the option‐value approach than under the NPV rule due to demand uncertainty. The results have implications for agribusiness decision‐making.     

Economic evaluation of ecosystem goods and services under different landscape management scenarios

Human-induced changes in the natural environment are affecting the provision of ecosystem goods and services (EGS). Land use plans rarely include the value of public ecosystem services such as climate regulation and biodiversity due to difficulties in valuing these services. In this study, we assessed total economic value for five important ecosystem goods and services under five future land-use scenarios using varying levels of costs, prices and discount rates. Results indicated that at higher discount rates normally applied to commercial activities, and assuming the current prices for goods and services, net present value (NPV) was highest for landscape management scenarios aimed at maximising agricultural production. Potential income from services such as carbon and biodiversity does not offset projected income lost from agriculture due to land-use changes. At higher discount rates, NPV was negative for the two scenarios aimed at enhancing the longer term ecological sustainability of the landscape. These results indicate that income from carbon sequestration and biodiversity conservation would need to be considerably higher than current levels in order to justify focusing management of this landscape on ecological outcomes. At lower discount rates (at levels normally associated with public investments), the more ecologically appropriate ‘mosaic farming system’ had the highest NPV, indicating that this type of system might be attractive for investors interested in longer term return horizons or wider public benefits. Higher income from carbon or biodiversity, or increased return from timber by using high value tree species, could potentially make more ecologically appropriate systems profitable at higher discount rates.     

实物期权在水利项目投资决策中的应用初探

分析对水利建设项目投资决策比较重要的3个经济效果评价指标：项目的投资回收期、净现值、内部收益率的特点,指出目前这3个指标存在的不足之处;通过对实物期权的性质及适用条件的分析,论证实物期权方法应用于水利建设项目投资决策中的必要性和可行性.     

Yield and income effects of rice varieties with tolerance of multiple abiotic stresses: the case of green super rice (GSR) and flooding in the Philippines

With the increasing frequency of extreme climatic events, the new challenge is to develop rice varieties that are tolerant of drought, water submergence, and salinity. There are now new high‐yielding green super rice (GSR) cultivars developed at the International Rice Research Institute with increased tolerance to multiple abiotic stresses. But a clear understanding of the economic benefits of these varieties under farmers’ production environments is not yet fully understood. In this article, we assess the yield and income effects of GSR rice varieties using a two‐year panel data from one province. We use matched samples from a propensity score matching method and a fixed‐effects model within a difference‐in‐difference (DID) framework to estimate the yield effects. The income effects were evaluated using the parameter estimates from the yield/production function model. The results of the ordinary least squares and DID fixed‐effects regressions reveal significant and positive effects of GSR varieties on yield. The most important finding is that the benefits from these varieties are strongly felt when there is flooding. This evidence was not as robust when matched samples were used. However, it is clear that the yield benefits from GSR varieties could improve rice food security and help alleviate poverty in the country.