A study on the bioenergy crop production function of land use in China

Based on the analysis of the bioenergy crop production function of land use,combined with the status quo of Chinese land use,the cultivation of energy plants and the bioenergy crop production function of land use had been analyzes and discusses in this paper.Results show that there were a lot of unused lands and marginal lands which can be planted bioenergy crops to perform the bioenergy crop production function of land use with great potentials; and currently there were no food production problems.Therefore,it was very important for China to emphasize bioenergy crops planting in order to fully use land resources in our country,moderate the energy crisis and increase peasants＇ income.     

A study on the evolution of land use for modern urbanization in China： 1952-2005

Modern cities and towns play as the central places of wealth accumulation for human-being, not only in the ways of settlement and material consumption as they were traditionally in ancient time, but also in the ways of social production and environmental pollution as they are mostly today. With such a transition, the meaning of land use for urbanization has broadened. According to the rule of human ecosystem, land use for modern urbanization can be divided into three types： namely, the direct, the indirect and the induced. However, its structure follows its own way of the direct 〈 the indirect 〈 the induced, rather different from what it normally happens in the natural ecosystem. This paper takes China as an example, calculates the evolution of the land used by cities and towns during 1952-2005 according to statistics, and then analyzes the evolvement of the structure. At last, it puts forward several countermeasures to ensure land resource requirement for urbanization in future.     

A study on the evolution of land use for modem urbanization in China: 1952-2005

used by cities and towns during 1952-2005 according to statistics, and then analyzes the evolvement of the structure. At last, it puts forward several countermeasures to ensure land resource requirement for urbanization in future.     

Human appropriation of aboveground net primary production in Spain, 1955-2003: An empirical analysis of the industrialization of land use

The human appropriation of net primary production (HANPP) is an indicator of the human domination of ecosystems that measures to which extent human activities alter the amount of biomass available each year in ecosystems. This paper analyses the development of aboveground HANPP (aHANPP) in Spain for the period from 1955 to 2003. During this period, Spain's agriculture underwent a transition from a largely pre-industrial to a highly intensified production system. Changes in land use patterns include a reduction of cropland area and an expansion of forest area. Results show that aHANPP declined from 67% of potential aNPP in 1955 to 61% in 2003. Biomass harvest strongly increased from 68 million tons dry matter biomass per year (Mt/yr) to 106 Mt/yr, with nearly all of this increase occurring on cropland. Productivity losses due to human-induced land conversions dropped significantly from 112 Mt/yr to 63 Mt/yr, mainly as a result of the surge in cropland productivity and the increase in forest area. Despite its decrease during the last decades, aHANPP in Spain is still at a remarkably high level in comparison with the global average or other industrialized countries.     

The opportunity cost of land use and the global potential for greenhouse gas mitigation in agriculture and forestry

This paper analyses the role of global land management alternatives in determining potential greenhouse gas mitigation by land-based activities in agriculture and forestry. Land-based activities are responsible for over a third of global greenhouse gas emissions, yet the economics of land-use decisions have not been explicitly modeled in global mitigation studies. In this paper, we develop a new, general equilibrium framework which effectively captures the opportunity costs of land-use decisions in agriculture and forestry, thereby allowing us to analyse competition for heterogeneous land types across and within sectors, as well as input substitution between land and other factors of production. When land-using sectors are confronted with a tax on greenhouse gas emissions, we find significant changes in the global pattern of comparative advantage across sectors, regions, and land types. Globally, we find that forest carbon sequestration is the dominant strategy for GHG emissions mitigation, while agricultural-related mitigation comes predominantly from reduced methane emissions in the ruminant livestock sector, followed by fertilizer and methane emissions from paddy rice. Regionally, agricultural mitigation is a larger share of total land-use emissions abatement in the USA and China, compared to the rest of the world, and, within agriculture, disproportionately from reductions in fertilizer-related emissions. The results also show how analyses that only consider regional mitigation, may bias mitigation potential by ignoring global market interactions. For example, USA-specific analyses likely over-estimate the potential for abatement in agriculture. Finally, we note that this general equilibrium framework provides the research community with a practical methodology for explicit modeling of global land competition and land-based mitigation in comprehensive assessments of greenhouse gas mitigation options.     

美国国家公园应对气候变化的经验及其对中国国家公园建设的启示

2017年随着《建设国家公园体制总体方案》的出台，中国的国家公园建设逐渐步入正轨。然而我国人口众多，幅员辽阔，气候条件复杂且生态环境脆弱，正在建立的国家公园极易受到气候变化所带来的不利影响，且我国关于国家公园应对气候变化的研究较少。美国的国家公园体制较为完善，在应对气候变化方面已有较为深入的探索。通过文献调研和比较分析法，以佛罗里达州大沼泽地国家公园和亚利桑那州大峡谷国家公园为例，分析其应对气候变化的方法与经验，并从气候监测、国家公园管理、适应性规划以及环境教育等方面对我国国家公园应对气候变化提出建议，使正在建设中的中国特色国家公园体制稳步推进。     

Effects of the Chinese arable land fallow system and land-use change on agricultural production and on the economy

This study focuses on economic effects of arable land fallow system and land-use change in China using a dynamic single-country, multi-regional computable general equilibrium model. Land supply is adjusted endogenously in our model. Land use in each of 31 provinces is tracked by a land-use change module, which is calibrated with satellite data. Our results reveal that the expansion of real output can be attributed to the increase in capital stock as a result of the growth of investment due to the imposition of the arable land fallow system in China. And the growth of investment is caused by the release of labor from agriculture The reduced supply of arable land in agricultural land contraction regions is partially offset by the increasing arable land in agricultural land expansion regions. Rural households benefit more than urban households from the arable land fallow policy due to relatively higher income and lower rural CPI.     

Getting fourteen for the price of one! Understanding the factors that influence land value and how they affect biodiversity conservation in central Brazil

Biodiversity policies are suffering an implementation crisis; the roots are deeply entrenched in the unfair competition between the public and private interests for suitable versus available land. In this article we propose a value-based equivalence method for compensation for the 20% compulsory reserves in the Taquari River sub-catchments, as legally required for central savannas of Brazil. Using regression techniques we analyzed 106 land deals in the Pantanal's watershed and identified the most significant variables influencing land value. We argue that the commonly used area-for-area, compensation mechanism, where 1 ha of compulsory reserve is missing, requires another hectare protected in the same catchments, instead of counteract habitat loss, is in fact harmful to biodiversity, stimulating progressive habitat destruction. We identified the economic forces behind deforestation and habitat fragmentation in the central savannahs of Brazil and proposed a market-based approach to counteract these forces using tools already available in environmental economics. We suggest that a dollar-for-dollar reference to determine land equivalence and compensation can better counter-balance the incremental losses from habitat destruction, while providing objectivity and transparency for trading alternatives.     

Global patterns of socioeconomic biomass flows in the year 2000: A comprehensive assessment of supply, consumption and constraints

Human use of biomass has become a major component of the global biogeochemical cycles of carbon and nitrogen. The use of land for biomass production (e.g. cropland) is among the most important pressures on biodiversity. At the same time, biomass is indispensable for humans as food, animal feed, raw material and energy source. In order to support research into these complex issues, we here present a comprehensive assessment of global socioeconomic biomass harvest, use and trade for the year 2000. We developed country-level livestock balances and a consistent set of factors to estimate flows of used biomass not covered by international statistics (e.g. grazed biomass, crop residues) and indirect flows (i.e. biomass destroyed during harvest but not used). We found that current global terrestrial biomass appropriation amounted to 18.7 billion tonnes dry matter per year (Pg/yr) or 16% of global terrestrial NPP of which 6.6 Pg/yr were indirect flows. Only 12% of the economically used plant biomass (12.1 Pg/yr) directly served as human food, while 58% were used as feed for livestock, 20% as raw material and 10% as fuelwood. There are considerable regional variations in biomass supply and use. Distinguishing 11 world regions, we found that extraction of used biomass ranged from 0.3 to 2.8 t/ha/yr, per-capita values varied between 1.2 and 11.7 t/cap/yr (dry matter). Aggregate global biomass trade amounted to 7.5% of all extracted biomass. An analysis of these regional patterns revealed that the level of biomass use per capita is determined by historically evolved patterns of land use and population density rather than by affluence or economic development status. Regions with low population density have the highest level of per-capita biomass use, high-density regions the lowest. Livestock, consuming 30-75% of all harvested biomass, is another important factor explaining regional variations in biomass use. Global biomass demand is expected to grow during the next decades; the article discusses some options and possible limitations related to such a scenario.     

Information and the operation of markets: tests based on a general equilibrium model of land leasing in India

This paper develops an estimable general equilibrium model of land leasing to test the extent to which information is commonly held in a village and whether village markets are efficient. Information regarding the relative farming skill of households is found to be widespread, but the assumption of perfectly efficient markets within the village is rejected. These results have ramifications for the estimation of agricultural household models and for our understanding of rural institutions. The model is derived from the primitives of the production technology, the extent of information and the distributions of assets and several household unobservables. Simultaneity and selection issues are dealt with explicitly in a two-stage maximum likelihood estimation procedure using panel data from India.     

Impacts of Sloping Land Conversion Program on the vegetation in loess hilly and gully area of northern Shaanxi

Aiming at alleviating the serious soil erosion, the Chinese government initiated the Sloping Land Conversion Program （SLCP） in 1999. Now; after 8 years of project implementation, the ecological recovery effects of the SLCP have become the hot issue of academic circle. This paper; raking the loess hill and gully area of northern Shaanxi as an example, presents a methodology for assessing the vegetation restoration effect of SLCP with normalized difference vegetation index （NDVI）. The key components include calculation of the Growing Season NDVI （GSNDVI）, and estimation of the NVDI change induced by climate and SLCP, respectively. Based on the method, the NDVI change between 2000 and 2006 was obtained using the GSNDVI that excluded the noise from snow and ice. After the part of total NDVI change caused to： climate variation was estimated using empiric formulae, we obtained the part induced by human factors, i.e. the SLCP The human induced part of ND VI change was considered as an approximation indicating the effect of the SLCP on the vegetation. Finally, we analyzed the ND VI change characters of the whole study area, different slope lands and different land use types by spatial statistics method. Results show that the vegetation condition is significantly improved by the SLCP, particularly land types that directly involved in the SLCP, such as steeply slope farmlands, degraded grasslands, etc.     

Attainment of combined optimal lipid values and the impact of lipid medication on cardiovascular outcomes and costs in a commercially insured population in the US

Abstract

Objective: To determine factors associated with the achievement of optimal lipid values (OLVs) and subsequent impact on clinical and economic outcomes.

Methods: An observational managed care database analysis was conducted among treatment-naïve adults with elevated cardiovascular (CV) risk, ≥12 months follow-up and full lipid panel from the 1st January 2002 to the 28th February 2005. Achievement of guideline-based levels for low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides was evaluated via laboratory data. Annual CV-attributable resource utilisation was assessed via medical and pharmacy claims data. Clinical and economic outcomes associated with the achievement of OLVs were assessed using multivariate regression.

Results: A total of 52,778 patients were followed for a mean (standard deviation) of 27 (10) months with 13% achieving combined OLVs at baseline and 23% after 4 years. Of patients, 69% did not initiate lipid-modifying medication. The achievement of combined OLVs reduced the risk of CV event (odds ratio = 0.86; 95% confidence interval 0.78–0.95), resource utilisation (inpatient visits: 3.36 vs. 4.41 per 100 patient years, p<0.0001; emergency department visits: 1.1 vs. 2.4 per 100 patient years, p<0.05) and costs: $703 vs. $903 per patient year, p<0.0001.

Conclusions: Simultaneous achievement of OLVs was rare in this patient population. Physicians should be encouraged to manage multiple risk factors aggressively to improve clinical and economic outcomes associated with CV disease.     

大中城市周边农地非农化进程驱动机制分析——基于中国130个城市面板数据的检验

本文收集1999-2006年全国130个大中城市的面板数据,对我国农地非农化进程的驱动机制进行了实证研究,发现就全国范围而言,非农人口的增加、产业集聚的形成、政府自身利益的推动、房地产投资的上升是导致大中城市农地非农化过程的主要原因。对大城市来说,由于需求关联循环累积因果关系的影响,产业集聚和房地产投资是农地非农化进程的主要驱动力。对中等城市而言,城市非农人口的增加才是农地非农化过程的最主要因素。因此,政府应根据不同规模城市的差别制定相应的城乡土地发展政策。     

环境规制与我国经济增长关系的区域差异研究——基于东、中、西部地区三次产业部门的数据分析

本文以2001-2010年全国东部、中部和西部地区的面板数据为样本,将区域经济增长细化为三次产业经济的增长,通过建立面板数据模型,分区域研究环境规制对各产业部门的经济增长效应,研究发现环境规制水平对我国三次产业的影响呈现出明显的区域差异性。环境规制水平与东部和中部地区的第二、三产业呈显著的正向相关关系,对西部地区第二产业的发展有显著的正效应,而对东、中部地区的第一产业和西部地区的第一、三产业的增长无显著影响。因此,应当采取相应的政策措施,以促进各区域环境规制与经济增长的协调发展。     

近60年渤黄海海冰灾害演变特征与经济损失浅析

在气候变暖、极端天气气候事件增多及承灾体脆弱性增大背景下,我国海冰灾害呈现出不易预测、破坏性大等新的特点。基于 1963-2016 年中国沿海海洋站海冰冰情数据及海冰灾害损失数据,分析了我国海冰灾害的变化特征及其影响。结果显示：我国渤海与黄海北部自 11 月中下旬由北往南开始结冰,各海区冰情存在较大差异。受气候变暖的影响,海冰冰情总体有降低的趋势,同时我国海冰冰情呈现约 10年的准周期性特征,且近年来极端天气气候事件的频次和强度不断增加,海冰灾害造成的影响进一步加重,2010 年以来由海冰灾害造成的直接经济损失高达 77 亿元,其中辽宁、山东两省受海冰灾害影响较为严重。因此,我国未来要进一步重视海冰灾害,增强防灾减灾能力建设,减轻灾害损失。