三峡库区农田氨挥发及其消减措施研究进展

从分析农田氨挥发的机理入手,在分析国内外氨挥发研究现状的背景下,综述了三峡库区农田氨挥发受气候、土壤理化性质、田间管理措施等因素的影响程度及其消减措施的研究进展,提出了应将农田氨挥发作为库区气态氮损失的研究重点,同时在研究方法、时空尺度、地域特殊影响因素,以及消减措施等方面进行更深入的探索。     

2008年冬季低温雨雪冰冻极端天气对农业生产的影响与对策

重点分析了2008年冬季极端天气对农业生产造成的影响,并对如何减少灾害损失提出一些对策。     

农户种植业结构调整的意愿及其影响因素分析——以环北京地区为例

通过对环北京地区140 km圈层以内(北京10个区县,河北25个县)50个村的490个农户进行随机调查分析,研究了该地区近年来农户种植业结构调整的意愿及其影响因素。结果表明,随着城市居民食品消费需求的变化,环北京地区农户种植业结构已经发生了相应的变化,选择种植蔬菜、水果和干果等高产值作物的农户越来越多。基于我国落后分散的小农经济基本国情和日益发达的交通运输条件,地理区位因素对农户种植业结构调整的影响逐渐减弱,而农户富裕程度、劳动力机会成本和国家相关政策在新的历史时期成为影响我国农户种植业结构调整选择的重要因素。     

《安徽农业科学》影响因子与全国平均值的比较

基于《中国学术期刊综合引证报告》的统计数据,将2001~2007年《安徽农业科学》影响因子和我国87种综合类农业科学学术期刊影响因子平均值进行比较。     

On-farm impacts of zero tillage wheat in South Asia's rice–wheat systems

The recent slow down in productivity growth in the irrigated areas of the Indo-Gangetic Plains of South Asia has led to a quest for resource-conserving technologies that can reduce production costs, save water and improve production. Findings from farm surveys are used to evaluate the on-farm impacts of zero tillage (ZT) wheat in the rice–wheat systems of India's Haryana state and Pakistan's Punjab province. ZT-induced effects primarily apply to the establishment and production costs of the wheat crop. Both study sites confirmed significant ZT-induced resource-saving effects in farmers’ fields in terms of diesel, tractor time and cost savings for wheat cultivation. Water savings are, however, less pronounced than expected from on-farm trial data. It was only in Haryana, India that there were significant ZT-induced water savings in addition to significant yield enhancement. The higher yield and water savings in Haryana, India result in significantly higher water productivity indicators for ZT wheat. In both sites, there are limited implications for the overall wheat crop management, the subsequent rice crop and the rice–wheat system as a whole. The combination of a significant “yield effect” and “cost-saving effect” makes adoption worthwhile and provide a much needed boost to the returns to wheat cultivation in Haryana, India. In Punjab, Pakistan, ZT is primarily a cost-saving technology for wheat cultivation. The prime driver for ZT adoption is not water savings or natural resource conservation but monetary gain in both sites. Water savings are only a potential added benefit.     

Prospects for Reduced Impact Logging in Central African logging concessions

Reduced Impact Logging (RIL) has traditionally been described as a set of forest management practices that reduce logging impacts and improve productivity. In this paper, we review the evolution of the logging sector in the Congo basin since the early 20th century. We argue that logging in the Congo basin has been little influenced by RIL until the recent regional Forestry Law reforms that started in Cameroon in 1994. RIL has not been integrated into the logging sector of the region as an independent body of knowledge, but more as a complement of the new mandatory management plans. In spite of its proven environmental and economic advantages, the role of RIL in improving forest management has been poorly understood, and we identify some causes of this situation. Finally, based on a regional study of 30 concessions, we analyse the frequency of some RIL-related practices and their relation with markets and certification schemes. We conclude that a clear definition of what RIL techniques are embraced by the logging sector is needed if RIL is to fully benefit from the recent development of new market and logging schemes based on certification, improved logging efficiency and a more transparent chain of custody.     

土地规划环境影响评价与建设项目环境影响评价的比较

结合国内外环境影响评价研究状况,对土地规划的环境影响评价(LUPEIA)和单个建设项目的环境影响评价(SEA)进行了较为全面的比较,指出了土地规划的环境影响评价与项目环境影响评价的异同,分析了项目环境影响评价对土地规划的环境影响评价的借鉴意义,为进一步开展土地规划的环境影响评价工作提供思路.     

抚育间伐对森林环境的影响

根据实测资料分析了抚育间伐对森林环境的影响,结果表明：随着间伐强度的提高,林内光照强度增加,空气湿度降低;在寒冷多湿地区,土壤肥力增加;而在温暖的气候条件下,土壤肥力则降低。     

Elsevier和Springer两大数据库中海洋学期刊SCI收录及开放获取情况分析

在对Elsevier和Springer两大最常用外文期刊数据库所收录的海洋学期刊进行详细调查的基础上,分析了两大数据库中海洋学期刊的SCI收录情况、影响因子在最近5年的变化情况以及这些期刊的开放获取情况。调查结果不仅反映了海洋学学术研究在近年的发展情况,而且为海洋学科图书馆借助开放存取资源进行馆藏建设提供了依据。     

人民币汇率改革对贵州省经济发展影响的理论与实证分析

2005年7月以来,中国实行的人民币汇率制度,对全球经济尤其是中国经济发展产生了重要的影响.本文以此为背景,从汇率决定理论的研究视角,运用经济学相关理论知识,分析汇率改革对经济发展的影响,并运用宏观经济数据对贵州省的主要经济指标进行实证分析,提出政策建议.