基于LMDI方法的海水养殖贝类碳汇分解研究——山东省2008-2012年的经验数据

本文以山东省海水养殖贝类为研究对象,对其2008-2012年的碳汇能力进行了估算,在此基础上,通过运用LMDI分解技术对碳汇量差异原因进行了研究,结果发现,海水养殖贝类的碳汇能力巨大,2008-2012年间山东省的海水养殖贝类碳汇总量呈递增趋势,贝类结构因素和产量因素对碳汇总量的增加都起到了一定的拉动作用,其中结构因素对碳汇量增加所起的作用要大于总产量因素对其的作用。     

基于灰色关联-TOPSIS法的中国沿海省份海水贝类养殖产业评价

运用灰色关联分析和逼近理想点分析方法,首先对影响海水贝类养殖产业的各因素进行关联分析,随后对我国沿海省份海水贝类养殖产业进行评价。关联分析结果显示:各影响因素的权重依次为海水贝类养殖产量(0.2079)海水养殖专业从业人员(0.2063)海水贝类养殖面积(0.2060)海水养殖生产渔船(0.2006)海水养殖产值(0.1791)。逼近理想解法分析得到各沿海省份评价排序情况。结果依次为:山东辽宁福建广东广西浙江江苏河北海南。     

贝类养殖项目利润管理多因素变动分析模型研究——以山东省烟台市X海水养殖场为例

论文利用在山东烟台市某海水养殖场开展入户调查时获取的数据,运用本量利分析的基本原理和计算机财务管理方法,对海水贝类养殖企业的利润管理进行了实证分析。论文建立的贝类养殖项目利润管理多因素变动分析模型,可以快捷地研究单因素变动对贝类养殖企业利润的影响和多因素变动对利润的综合影响,以及快捷计算出贝类养殖企业盈亏平衡点。研究结论对我周贝类养殖企业项目经济决策和国家政策制定具有一定的参考和借鉴意义。     

山东省贝藻养殖碳汇能力评估

本研究根据山东省贝类与藻类养殖产量数据对2015-2020年山东省贝藻养殖过程中从近海中移出的碳汇量及碳汇价值进行了估算,结果表明,2015-2020年,山东省在养殖滤食性贝类与大型藻类过程中,从近海中移出碳量321万吨,相当于减排CO₂ 1178万吨,折合人民币26.74亿元。藻类固碳能力强,但贝类固碳时间更持久。因此,结合山东省目前贝藻养殖产业现状,建议适当调整贝类养殖结构,加大对固碳能力强的蛏和贻贝的养殖,并对贝藻养殖的生态效益价值进行补偿以进一步促进贝藻产业发展,进而为山东省在碳交易市场中争取合理的碳份额提供依据。     

福建海洋渔业产量结构的灰色关联分析

论文运用灰色理论中的关联分析方法,对2001～2010年福建省海洋渔业产量结构进行分析,结果表明:海水产量对水产品总量的贡献率大于淡水产量;海水养殖产量大于海洋捕捞产量;海水养殖中贝类占主体地位;对近海捕捞贡献最大的种类是鱼类,其次是甲壳类,贡献最大的作业方式是拖网,其次是张网.论文结合研究,提出应拓展空间、发展养殖、提升科技水平、制定发展规划等方面的建议,以期为福建海洋渔业可持续发展的决策提供参考.     

浅谈海水贝类养殖中的问题及对策

我国海水养殖发展规模不断扩大,现已成为颇具规模且发展前景广阔的养殖产业,在质量、产量方面均有明显提升,贝类养殖更是在推动沿海地区经济发展、提升沿海人民生活质量和经济水平方面发挥了重要作用,但是在养殖过程中存在一些问题,阻碍了海水贝类养殖平稳发展。分析了当前我国海水贝类养殖中存在的问题,并据此提出针对性解决策略,以期为贝类养殖质量提升提供参考。     

海水养殖贝藻类碳汇效率的区域比较研究

借助数据包络分析法,选取辽宁省、山东省、浙江省、福建省、广东省为考察对象,将各省海水养殖贝藻类总产量、从业人口数量、育苗量、养殖面积设定为投入指标,将各省海水养殖贝藻类固碳总量设定为产出指标,结合2003-2015年数据,对上述五省海水养殖贝藻类碳汇效率进行测度和分析。实证结果表明:五省海水养殖贝藻类碳汇效率发展不平衡。其中,广东省(0.996)、山东省(0.975)、福建省(0.972)较高,辽宁省(0.912)稍低,浙江省(0.760)最低,均未实现DEA有效。基于分析,论文从投入角度对五省分别提出优化建议,以期为五省更好地发挥海水养殖贝藻类的碳汇功能提供理论依据。     

基于B-S期权定价模型的碳汇渔业价值评估——以海水养殖藻类为例

海洋生物的碳捕获能力非常强大,"蓝碳"已经成为全球碳循环的中坚力量。合理评估海洋渔业碳汇价值可以有效促进海洋碳汇市场交易的发展。论文基于2004-2015年中国海水养殖藻类相关数据,采用B-S期权定价模型,以海水养殖藻类为例,对我国碳汇渔业价值加以评估,结果显示:以1年行权期限来核算的2004-2015年中国海水养殖藻类碳汇期权价值均为正值,它本身受到碳汇量、碳交易价格、固碳投入成本、资产价值变动及无风险利率等多个因素的影响。渔业碳汇期权交易市场的建立可以使碳汇需求者灵活规避不确定性带来的交易风险,使渔业碳汇价值评估更为公允。     

中国海水养殖生态经济系统耦合关系及驱动因素分解

本文采用Tapio脱钩弹性指数,从时间和区域两个维度对2008—2016年中国海水养殖业生态经济耦合关系进行测度。结果表明,我国海水养殖生态经济耦合关系从以扩张性负脱钩为主改善为以扩张连接为主,宏观层面整体趋优,但仍未实现生态经济强脱钩;省域层面的生态经济耦合关系差异巨大,可划分为弱脱钩型发展、无序波动型发展、耦合关系改善型发展、耦合关系恶化型发展4种。针对脱钩弹性指数变动的影响因素,本文采用LMDI方法从养殖规模、养殖结构和养殖技术3个层面进行分解,结果表明养殖规模是我国海水养殖业生态经济耦合关系恶化的主要原因,且影响作用较大;而养殖结构和养殖技术是生态经济耦合关系改善的主要原因,但作用大小较为微弱。     

中国海水养殖业比较优势分析

海水养殖业在中国海洋渔业中占有重要地位。为进一步优化我国海水养殖业的生产布局提供思路,本研究采用资源禀赋系数和综合比较优势指数模型对2012-2017年中国海水养殖业的资源禀赋情况、规模比较优势、效率比较优势以及综合比较优势进行量化分析。结果表明:(1)中国海水养殖目前主要受自然条件影响,具有海水鱼类和甲壳类养殖资源禀赋的地区主要集中在南方,而具有海水贝类和藻类资源禀赋的地区则主要集中在北方。地区资源禀赋决定了我国海水养殖业的基本空间格局。(2)目前中国海水养殖的生产布局基本符合比较优势原则,具有资源禀赋优势的地区,形成了突出的规模比较优势,进而导致其综合比较优势也较显著。(3)各地海水养殖业的比较优势具有一定差异,福建的比较优势体现在海水鱼类和藻类养殖方面,广东和海南的体现在海水鱼类和甲壳养殖方面,山东的则体现在海水贝类和藻类养殖方面。     

黑龙江省产业能源碳排放因素分解及减排分析

能源消费是碳排放的主要来源。随着黑龙江省经济的快速发展,能源消费的急剧增长以及以煤为主的能源结构在一定时间内很难改变,因此,碳排放量在短时间内很难下降。本文分析了1980-2010年黑龙江省三大产业碳排放变化情况,并对黑龙江省1980和2010两年不同行业能源利用碳排放总量进行对比。采用LMDI分解法,定量分析了1980-2010年间,经济规模、产业结构、技术进步与能耗结构四个因素对黑龙江省产业碳排放增量的影响。研究发现,经济规模效应是正向决定性因素,能耗结构调整的影响效果不显著,技术进步与产业结构效应是负向决定性因素。最后提出了相应的减排政策建议。     

China's changing diet and its impacts on greenhouse gas emissions: an index decomposition analysis

With increasing awareness of agriculture's contribution to global greenhouse gases (GHGs) and China's position as the world's top GHG emitter, there is heightened attention to the embodied emissions in China's food consumption. China's diet has shifted to include more fruit, vegetables, meat and dairy. Not surprisingly, GHG emissions from food consumption have also increased substantially. This analysis links China's food consumption with the emissions of food production industries in China and its trade partners to determine the effects of dietary change on GHGs since 1989. We utilise high‐resolution food production and emissions data to perform a logarithmic mean Divisia index decomposition to attribute changes in GHG emissions to the scale, supply structure, demand structure and efficiency effects resulting from Chinese dietary changes over a 20‐year period. This study finds that while countries supplying food to China contribute little to China's food‐related GHGs, demands for meat and dairy play a much larger role, driving up emissions. The overall scale of increased consumption of all food further propels growth in GHG emissions. Results indicate, however, that while food consumption in China more than doubles between 1989 and 2009 improvements in technological efficiency limit the rate of increase.     

Consumption inequality between farm and nonfarm households in Taiwan: a decomposition analysis of differences in distribution

Consumption has been recognized as a more reliable indicator of household well‐being than income. Although a considerable body of literature has examined income inequality between farm and nonfarm households, little is known about inequality in consumption. This research aims to fill this knowledge gap by investigating consumption disparity between farm and nonfarm households. Using a nationally representative household survey from Taiwan, we apply an unconditional quantile regression‐based decomposition method to decompose the differences in the distribution of household expenditure between these farm and nonfarm households. The results indicate that differences in the observed characteristics between these two types of households explain most of the consumption inequality. Moreover, the difference in the education level of the farm operator, household income, and the degree of urbanization are particularly important.     

Three decades of productivity change in French beef production: a Färe‐Primont index decomposition

The Färe‐Primont index is used to evaluate total factor productivity (TFP) change and its components for a sample of French suckler cow farms in grassland areas in 1985–2014. The results reveal an increase in TFP of 6.6 per cent over the whole observation period, with technological progress being the major source of productivity growth. Meanwhile, efficiency decreased. Farms experienced great technological progress from 1991 to 2000. From a methodological point of view, the comparison with results obtained with Malmquist indexes shows similar trends but different magnitudes, with the Malmquist index overestimating the TFP and technological changes compared to the Färe‐Primont index. In addition, the use of a sequential approach that restricts technological change to being positive or null allows for the precise calculation of technology changes, disregarding the effects of external conditions that are captured in efficiency changes. Finally, the estimation of full dimensional efficient facets (FDEFs) that guarantees the positivity of all shadow prices used to assess the mix efficiency component of TFP change is promising.     

Nitrogen fixation during decomposition of sugarcane (Saccharum officinarum) is an important contribution to nutrient supply in traditional dryland agricultural systems of Hawai'i

Nitrogen (N) is unique among essential elements required for life, in that it must be fixed from the vast atmospheric reservoir before most organisms can use it. Prior to industrial nitrogen fixation, many agricultural systems were limited in their productivity by N. What sustained N in the ancient Hawaiian dryland (rain-fed) agricultural systems that lacked legumes or other known significant N inputs? N-fixation during sugarcane (Saccharum officinarum) growth and litter decomposition was examined in settings representing pre-European Hawaiian agriculture. We did not detect associative N-fixation during the growth of five Hawaiian sugarcane cultivars. In contrast, N-fixation during the decomposition of leaf and stalk material was important. We found that the depth of the mulch layer significantly affected N-fixation levels during decomposition; values of N-fixation in different depths of senesced leaf litter ranged from 0.69 to 1.36?gN/kg of litter integrated over the lifetime of decomposition. Compared to senesced leaf litter, N-fixation during decomposition of non-senesced leaf litter was ～77% and stalk material ～140% per unit mass. Peak rates of N fixation occurred between 200 and 400 days of decomposition, and ranged from 1.37 to 3.27?gN/kg/yr. Our empirical results were extrapolated to represent the traditional Hawaiian cropping system; we calculated N-fixation inputs of 4.8–39.0 kgN/ha/yr, with fixed N adding 17–40% of the amount of N added through litter. Findings indicate that significant N may be introduced into natural cropping systems through mulching practices and that small changes in practices greatly alter the total inputs. The use of mulch was likely an important source of N in pre-industrial settings and may be used in contemporary systems to reduce nitrogen fertilizer requirements.