辽宁人工增雨作业条件的研究

以2009年5月17～18日降水天气过程为例,分析并总结了辽宁地区常用的人工增雨作业条件。将作业条件分为两大类,即宏观天气作业条件和微观云物理作业条件,分别阐述各自的指标与判据,及其在人工增雨作业方案制定和实时指挥中的作用和应用。     

构建珠江三角洲地区稳定森林生态安全体系的探讨

文章根据珠江三角洲地区森林生态安全体系建设现状的详细调查数据,深入分析存在的主要问题,提出了构建珠江三角洲地区稳定森林生态安全体系的基本思路及政策建议。     

中国亚热带森林小流域植物生长驱动下矿物风化评估

Plant growth contributes to mineral weathering, but this contribution remains poorly understood. Weathering rates in an aggrading forested watershed in subtropical China were studied by means of geochemical mass balance. Rainfall, dry deposition, and streamwater were monitored from March 2007 to February 2012. Samples of vegetative components, rainfall, dry deposition, streamwater, representative soils, and parent rock were collected and determined for mass balance calculation and clarifying plant-driven weathering mechanisms stoichiometrically. Ignoring biomass, weathering rates of Ca²⁺, Mg²⁺, Na⁺, and Si were 25.6, 10.7, 2.8, and 51.0 kg ha^-1 year^-1, respectively. Taking biomass into consideration, weathering rates of Ca²⁺, Mg²⁺, and Si and the sum of weathering rates of Ca²⁺, Mg²⁺, Na⁺, K⁺, and Si were 2.6, 1.8, 1.2, and 1.5-fold higher than those ignoring biomass, respectively. This is attributed to plant-driven weathering due to the nutrient (e.g., Ca²⁺, Mg²⁺, and K⁺) absorption by vegetation and substantial proton production during assimilation of these nutrients, with the former acting as a pump for removing weathering products and the latter being a source of weathering agents solubilizing mineral components. The same pattern of weathering, i.e., higher rates of weathering with than without including biomass in mass balance calculation, was reported in previous studies; however, the extent to which plants drive weathering rates varied with vegetation types and climatic zones. The documented biological weathering driven by plants is expected to play a critical role in regulating nutrient cycling and material flows within the Earth’s Critical Zone.     

Rehabilitation Experiment at Menzel Habib,Southern Tunisia

This long - term rehabilitation experiment is located near Menzel Habib, in the arid zone of southern Tunisia in a site with unambiguously degraded vegetation and soil, caused by a decades - old practice of overexploitation (grazing and plow agriculture). The fundamental premise is that by reintroducing an appropriate combination of native perennial plants, a simplified version of a previously occurring vegetation (and ecosystem) could be reinstated that would utilize the sparse and irregular water resources available in an efficient and complementary fashion, while also showing considerable resistance and resilience to moderate livestock grazing. The long - term goal is, on the basis of such a simplified system, to progressively achieve, through additional reintroductions and other manipulations, a state similar to that of the "ecosystem of reference," an example of which is provided in the nearby Bou Hedma National Park. In this paper we report various aspects of the experiment related to germination and establishment of four supposed keystone species (Rhanterium suaveolens, Plantago albicans, Stipa lagascae, and Cenchrus ciliaris) sown in field conditions, and compared to the ecosystem of reference for a number of parameters related to the structure and functioning of the ecosystems under study. Over a 4 - year period, distinct changes in the desired direction were observed in the experimental plots, and positive effects of controlled grazing were also recorded.     

阿根廷专属经济区内鱿钓渔场分布及其与表温关系

根据2008-2011年中国鱿钓船在阿根廷专属经济区内的生产统计和表层水温(SST)的资料,对渔获量组成和渔场分布情况进行了分析,同时利用Marine Explorer软件和K-S统计方法对渔场分布与SST的关系进行了研究,推测出各月中心渔场的最适SST。结果表明:阿根廷专属经济区内鱿鱼产量在2-4月份较高,且波动较大;产量主要集中在44°～52°S、60°～65°W海域,约占总产量的70%以上,各月产量的空间分布有较大差异,作业渔场总体上不断北移。2-8月中心渔场各月适宜SST范围分别为11～14.5℃、9.5～12℃、9～10℃、9～9.5℃、7～9℃、7.5～9℃、7～10℃,并通过了K-S检验。研究建议,今后应收集更为详细的包括生物学在内的生产统计数据,结合不同产卵群体的特点,对资源变动和渔场变化进行系统和科学分析,为合理利用西南大西洋阿根廷滑柔鱼资源提供基础。     

新型城镇化背景下长三角城市群产城融合路径探讨

产城融合是针对城镇化推进的形势和问题提出的新理念,作为产城融合进程中产业繁荣的投入要素和城市建设的服务对象,人的发展是产城融合的出发点和根本落脚点。因此在人本视角下以产-城-人系统协同发展为导向探究区域产城融合进程和路径具有重要意义。基于城市建设、产业发展和人的发展三者的内在作用机制,利用熵权法将长三角城市群的产城融合划分为8种类型。结果表明,人本导向下产业繁荣、城市建设和人的发展三维产城融合发展体系存在内部协同机制,各地在新型城镇化建设过程中应当充分考虑三者之间的联系,建立和谐互促的良好发展体系。此外,各城市间的产城融合发展情况具有较为明显的差异性,实现产城人和谐发展的切入点因而有所不同。各城市应当结合自身产、城、人的发展现状,因地制宜地完善发展战略,进一步推进新型城镇化进程。     

河西走廊凉州绿色农业示范区耕地土壤养分及栽培模式影响分析

位于甘肃河西走廊的凉州区是2006年4月经中国绿色食品协会批准、在西北干旱内陆地区建立的首批五十个国家重点绿色农业示范区之一,本研究以绿色农业理念为基础,通过大范围调查取样、测试分析,对绿色农业示范区内耕地土壤肥力状况进行综合分析评价,并对比分析了栽培模式对土壤质量的影响,设施栽培土壤有机质低于大田土壤,而全氮、全磷、全钾、碱解氮、有效磷、速效钾均高于大田,全盐量远远高出大田4倍。     

杨凌城区雨水资源利用潜力计算及其效益分析

应用径流系数法分析了杨凌示范区城区雨水资源利用潜力.2007年可直接收集利用的雨水总量为123.91万m3,占该年杨凌城区总用水量的28.3%;可处理后回用的雨水总量为367.15万m3,但目前仅有占城区总面积1.98%的绿地利用雨水12.93万m3,其它均未予利用;预计到2020年,以枯水年计算,可直接收集利用的雨水总量为3 233.03万m3;可处理后回用的雨水潜力巨大.并进一步对杨凌城区实施雨水利用后可能产生的经济、社会和生态效益进行了评价分析.     

基于GIS的闽东地区晚熟果树生态区域选择方法之实现

350013福建省农业科学院土壤肥料研究所     

成渝经济区农地适度规模经营方式及其环境效应差异比较

以成渝经济区为研究区,比较成渝地区农地经营方式转变的地域差异,评估农地经营方式转变的可持续性.选取成都平原区的广汉市和重庆山地丘陵区的江津区为研究样区,基于两个区域的1 102份调查数据,运用能值分析法分析两地农地经营方式转变的差异.由于资源禀赋、家庭特征、经营方式、流转市场、流转价格等因素的差异影响,江津区与广汉市农户农地流转呈现区域"悖反"现象;从能值分析来看,广汉市通过规模化、产业化、机械化的大生产模式提升农业科技装备水平,降低投入、提高农业生产率,实现了良性的农业集约化;而江津区通过高投入—高产出的高效农业产业模式大幅提升农业产出,但过度追加不可更新要素的投入方式却不可持续,引起了劣质的农业集约化.因此,就转变农地经营方式而言,成都平原区应着眼于"降本增效",发展规模化、产业化、机械化的大生产模式;重庆山地区应着眼于"提质增效",以农业科技、装备和设施更新为驱动发展生态农业.