我国农村雨水综合管理措施研究

针对我国已进入城市化快速发展的新时期,农村雨水仅考虑雨养农业的雨水集蓄利用已远远不能满足社会需求的现状.分析了我国农村雨水管理利用存在的问题;借鉴当代城市雨洪管理经验,提出了我国农村不同场地的雨水综合管理应用措施,可为我国新农村建设中出现的水资源短缺和水污染问题提供建议和对策.     

品种多点试验中最优地点数和重复次数的确定

本文给出几个确定品种多点试验中最优地点数和每一地点内各参试品种最优重复小区数的公式，还给出实例．     

Construction and analysis of knowledge graphs for multi-source heterogeneous data of soil pollution

The decommissioning and overall relocation of urban industrial enterprises have generated a large number of decommissioned contaminated sites, and the leftover soil pollution is gradually becoming a major problem that restricts urban green development and damages human health. Deep mining and efficient management of site soil pollution information through digitization and informatization are needed to solve these problems more accurately and efficiently. Knowledge mapping for visual analysis of relevant pathways is a forward-looking approach in soil contamination management that does not require complex testing instruments, thus saving research manpower, time and cost. Data associated with contaminated sites come from a wide range of sources and have different structures. Through the natural language processing technology of computer, suitable methods such as entity recognition, relationship recognition and knowledge fusion are selected to extract various types of information from contaminated sites and establish semantic networks for fast targeting of soil contamination sources, thus providing a more convenient solution. In this paper, we propose a knowledge graph construction method for multi-source heterogeneous data of contaminated sites, find sulphide contamination sources through visual analysis of knowledge graph and explore the application prospects of natural language processing techniques such as knowledge graph in contaminated site management.     

K/Ca and NH4/Ca selectivity of hydroxyaluminum-interlayered vermiculite and montmorillonite: Contribution from regular and frayed edge exchange sites

Cation distribution in adsorbed and solution phases and their mobility in the soil profile are largely influenced by the cation exchange capacity and selectivity coefficient of the soil. Vermiculites (Vt) and montmorillonites (Mt) in acid soils and sediments are frequently interlayered by hydroxyaluminum (HyA). Such interlayering causes significant changes in various properties of Vt and Mt. We evaluated the contribution of HyA-induced frayed edge sites (FES) in Vt and Mt to the overall selectivity of K/Ca and NHJCa. A more preferential adsorption and exchange of K to Ca was observed in the case of Vt in contrast to Mt. The overall K/Ca selectivity of Vt increased markedly by HyA-interlayering, whereas that of Mt was slightly affected. An increased overall K/Ca selectivity, especially of Vt was also observed due to the larger amount of HyA adsorption at higher initial basicity of the HyA ionic solution. Selective adsorption of K and NH₄ predominantly occurred on the FES. Interlayering substantially enhanced such FES contribution. The overall K/Ca and NH₄/Ca selectivity coefficients did not indicate any striking competitiveness of NH₄ with K, unlike that for the natural micaceous clay minerals. However, the parameter of FES contribution suggested that NH₄ could be slightly more competitive with K for the FES. The relative abundance of FES on different clay specimens determining K/Ca and NH₄/Ca selectivity and a slightly higher preference of NH₄ to K on FES played a major role at low K or NH₄-saturation.     

Effect of hydrologic regime and forest age on Collembola in riparian forests

The principal objective of the study was to assess factors of primary importance for collembolan community variability measured in riparian forest stands of different age after traditional clear cutting within natural and altered hydrologic regimes. The study was conducted in the Ukrainian part of the Latorica river floodplain where the largest stands of the highly protected medio-European Querco—Ulmetum minoris fluvial forests can be found. Six oak forest stands were investigated on the river floodplain: three in a natural section (inside levee) of the floodplain, which have their original features preserved with periodical inundation, and three in a section separated by a flood control embankment (outside levee) and subjected to serious damage by drainage. In each section the three stands sampled were represented by different ages regenerated with clear-cutting (>3 years, >8 years and >112 years).Differences in hydrologic regimes were central to identification of a predictable and explainable percentage of variation in species composition of Collembola communities in fluvial forests. The hydrologic regime factor was correlated with the basic structural attributes of collembolan communities, such as abundance, species richness and some ecological traits. Season accounted for a higher degree of variation in collembolan communities than did the age of forest stands. We conclude that differences in hydrologic regime are of much higher importance in structuring collembolan communities in riparian forests than are the ages of stands.     

良好农业规范(GAP)在蔬菜基地中的应用——基于面板数据和语言信息的农产品安全评价

针对良好农业规范(GAP)在蔬菜种植基地实施中,审核专家的评价信息仅做简单汇总而没有进行充分利用和分析,语言评价信息易损失和扭曲、限于平面数据集结等问题,以山东省6个备案蔬菜种植基地2001-2006年期间的评价为例进行了实证研究.提出了一种基于语言信息和面板数据的综合评价方法,据GAP标准构建了蔬菜基地的农产品安全评价指标体系,统计了GAP审核专家就6个基地的评价信息,对信息分别进行多指标和时序加权集结,得到各基地的综合评价结果,并对结果进行分析,充分利用评价信息,用以指导基地在GAP实施中的改进.研究表明以上方法可以有效地将语言评价信息进行集结,避免信息损失,并能够体现决策者对不同时期的重视程度.该方法将促进良好农业规范GAP标准的推广和应用,实现农产品安全管理的目标.     

浅析绿化在大遗址环境保护中的作用

揭示了目前我国遗址地绿化普遍存在的若干问题并进行了分析,提出了绿化在遗址地环境保护中的三大作用。     

Twenty-six-year response of ponderosa pine and Douglas-fir plantations to woody competitor density in treated stands of madrone and whiteleaf manzanita

Ponderosa pine (Pinus ponderosa Dougl.) grown in mixture with whiteleaf manzanita (Arctostaphylos viscida Parry) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) grown in mixture with Pacific madrone (Arbutus menziesii Pursh) in southwestern Oregon showed an increase in growth with removal of competing woody cover. Both conifer species had roughly one-third the volume at plantation ages 26–27 when grown with uncontrolled competition compared to where woody competition was completely controlled at age 2. Intermediate levels of competitors usually led to intermediate levels of growth, but this was more evident with Douglas-fir than pine. When competition was reduced or removed, height/age relationships for Douglas-fir at plantation ages 23 and 27 reflected medium site quality rather than low quality as estimated from adjacent stands, indicating that these sites are potentially more productive than perceived with uncontrolled dense woody cover. These studies support the concept that competition management may allow some poor sites of ponderosa pine or Douglas-fir to be managed on the basis of a higher site potential.     

Vegetation structure,composition and effect of pine plantation harvesting on riparian buffers in New Zealand

The composition and structure of vegetation within riparian buffers prior to, and immediately post-harvesting in a managed radiata pine (Pinus radiata D.Don) forest is described and compared with riparian buffers in residual adjoining native forest on the Coromandel Peninsula, New Zealand. One hundred and twenty-one species (71% native) representing life forms from grasses to trees were recorded. The highest species richness, including both native and adventive (non-native) species, was found in riparian buffers in the post-harvest and native reference sites which had 18–25 species per site. Riparian buffers in mature pine plantations contained a mix of native species that was generally similar to, and not significantly reduced in species richness, from the reference native forest. Native species comprised 82–92% of the total cover in mature pre-harvest sites (irrespective of riparian width), and 99.8% in native reference sites. Compared with native forest the principal difference was a reduction of total cover in the upper tiers (5–12 m), and some increase in cover in the lower tiers. Adventive species in post-harvest sites comprised 16–67% of the total cover and were most frequently found in riparian areas highly disturbed by recent harvesting of the pines, particularly where riparian buffers were narrow or absent. Invasion by light-demanding adventives is expected to be temporary and most species are likely to be shaded out as the new rotation of pine trees develops. Radiata pine plantations in Whangapoua Forest can provide suitable conditions for the development of riparian buffer zones that will become dominated by native species, similar in richness and structure to neighbouring native forest.     

河岸带生态系统管理模型研究进展

（西南大学资源与环境学院,重庆数字农业重点实验室,重庆 400716）