基于灰色关联分析的农业生态系统能量产投研究

集成能量投入-产出分析和灰色关联分析方法,分析1961-2005年我国农业生态系统的能量投入-产出及能效率的变化,找出影响其变化的主导因素.结果表明:能量投入以畜力、有机肥和化肥为主,农业机械能和农业劳动力能比重小;随着能量投入的增加,单位耕地面积上的能量产出在波动中增长,1970年以来高于世界平均水平,但能效率在波动中下降.能效率与农业劳动力能和畜力能等传统动力能的关联性强,有机肥能投入减少对能效率的下降影响较大,化肥能的大量投入对总能量产出的贡献有限.因地制宜地增加机械能、提高有机肥能比重,有助于提高能效率.     

农户对山核桃生态化经营模式的意愿分析

山核桃Carya cathayensis产业是浙江省林业特色产业之一,是产区林农收入的主要来源,但传统经营模式已经引起生态性问题,推广山核桃的生态化经营模式成为当务之急。以山核桃主产区浙江省临安市、淳安县为案例,通过对5个乡镇152户农户的抽样调查和多群体的参与式访谈,深入分析了山核桃生态化经营模式的选择意愿及其动因。结果表明,林农在经营决策中注重经济利益,经营成本、技术和资金是影响林农采用生态经营意愿的主要因素,林农意愿区间差别显著。推行山核桃生态化经营模式应从宣传教育、技术研发、林道建设、完善信贷等方面展开。图2表3参14     

集约化奶牛场污水磷污染指数的测定

采集集约化奶牛场四季节污水样进行磷含量测定,计算出奶牛场污水磷污染指数,并对四季节间磷污染指数差异进行比较分析。结果显示,四季节奶牛场污水磷含量春季最高,冬季最低,污水磷污染指数呈现与其相同的变化规律。     

无线射频识别技术在规模化奶牛场中的应用

介绍了无线射频技术作为一种全新的识别和管理技术在现代化奶牛场中的应用情况,分析了该技术在规模化牛场管理中的优势所在,并讨论了该技术在实际应用中暴露的一些问题。     

养鸡场循环经济的基本模式和主要问题及对策

近几年来,人们对养鸡场的污染治理—循环经济模式进行了不少的研究,但归纳起来,主要是肥料化、饲料化和沼气化3种模式。该文主要对这3种模式进行阐述,并就这3种模式存在的主要问题及其对策进行了探讨。     

辽宁省北票市林业有害生物普查简述

辽宁省北票市自2003年春季-2004年年末开展了1986年以来首次大规模的林业有害生物普查工作,通过普查,基本摸清了北票市林业有害生物以及天敌昆虫的分布、种类、分布地点、发生面积及危害情况,为科学分析北票市主要林业有害生物的发生发展趋势,明晰今后林业有害生物治理工作的开展思路,制定合理的林业有害生物治理方案,更加有效地控制、封锁和扑灭各类林业有害生物提供了相应的依据。     

北京市农机小额贷款现状调查与发展建议

对北京市郊区县农机户、农机服务组织、农村商业银行、农机管理部门人员进行电话调研,了解了各类主体对农机小额贷款的需求、看法,以及小额贷款运行情况。经分析,认为农机户有较强的贷款潜在需求,但现实贷款利率高、担保难、贷款手续繁琐,以及银行认为农机行业较种养业回收期长不愿意放贷等因素制约着贷款需求的满足。要解决贷款难的问题,就要重点从降低贷款使用成本和银行贷款风险入手,通过建立第3方担保和补贴机制,兼顾贷款供需双方利益,从而让银行愿意放贷,农民能够贷到款,达到农机户小额贷款供需的平衡。     

京郊农机配套问题初见

对京郊农机化发展现状分析后发现,北京市拥有庞大的农机总动力,但综合机械化作业水平却偏低,机械化作业和配套农机具水平达不到设施农业发展的要求。提出剥离不可用的动力机械、提高大马力拖拉机的利用率、发展特色设施农机具、重点发展与小型拖拉机配套的小型农具的建议。     

Long-term effect of an ectomycorrhizal inoculum and other treatments on survival and growth of Populus hopeiensis Hu et Chow

We evaluated the effects of direct use of an ectomycorrhiza fungal inoculum (Boletusedulis) mixed with indolebutyric acid (IBA), super-absorbent polymers (SAP) and organic compound fertilizer on the survival and growth of Populus hopeiensis saplings on a semiarid site in Inner Mongolia, China, during the first 5 years after planting, and the practical feasibility of using this inoculum mixture over large semiarid areas in North China.     

Tropical reptiles in pine forests: Assemblage responses to plantations and plantation management by burning

Worldwide, the land area devoted to timber plantations is expanding rapidly, especially in the tropics, where reptile diversity is high. The impacts of plantation forestry and its management on native species are poorly known, but are important, because plantation management goals often include protecting biodiversity. We examined the impact of pine (Pinus caribaea) plantations, and their management by fire, on the abundance and richness of reptiles, a significant proportion of the native biodiversity in tropical northern Australia, by (i) comparing abundance and diversity of reptiles among pine plantations (on land cleared specifically for plantation establishment), and two adjacent native forest types, eucalypt and Melaleuca woodlands, and (ii) comparing reptile abundance and richness in pine forest burnt one year prior to the study to remove understorey vegetation with pine forest burnt two years prior to the study. We also examined the influence of fire on reptile assemblages in native vegetation, by comparing eucalypt woodland burnt two years prior to the study and unburnt for eight years. To quantify mechanisms driving differences in reptile richness and abundance among forest types and management regimes, we measured forest structure, the temperatures used by reptiles (operative temperature) and solar radiation, at replicate sites in all forest types and management regimes. Compared to native forests, pine forests had taller trees, lower shrub cover in the understorey, more and deeper exotic litter (other than pine), and were cooler and shadier. Reptile assemblages in pine forests were as rich as those in native forests, but pine assemblages were composed mainly of species that typically use closed-canopy rainforest and prefer cooler, shadier habitats. Burning did not appear to influence the assemblage structure of reptiles in native forest, but burning under pine was associated with increased skink abundance and species richness. Burned pine was not warmer or sunnier than unburned pine, a common driver of reptile abundance, so the shift in lizard use after burning may have been driven by structural differences in understorey vegetation, especially amounts of non-native litter, which were reduced by burning. Thus, burning for management under pine increased the abundance and richness of lizard assemblages using pine. Pine plantations do not support the snake diversity common to sclerophyllous native forests, but pine may have the potential to complement rainforest lizard diversity if appropriately managed.