超低密度油菜田高效立体种植模式的研究与推广

通过田间小区试验和大田试验示范相结合、并采用多年多点的单因子控制研究,建立了油菜田超低密度栽培与间套种相结合的高效立体种植模式。6年连续示范与推广,油菜套种7种不同农作物三茬四作和四茬五作种植模式平均年产值达75112.50元/hm~2,而传统油-稻-稻耕作制平均年产值只有18612.00元/hm~2,以油菜为主栽作物的高效立体种植法比传统栽培法增加产值56500.50元/hm~2,是传统栽培法的4.04倍。超低密度油菜田高效立体种植模式有利于调动城市郊区农民种植油菜的积极性,提高种田的经济效益。     

城市地价监测点配置模式研究

地价监测点配置关系到城市地价水平的真实反映，影响到我国城市地价监测体系的系统性和规范性。本文提出以空间分层抽样技术为基础，首先确定城市地价监测点总量，然后选择一定的指标，分别确定地价监测点在城市内不同区域、不同用地类型、不同土地级别中的分布，经综合平衡，最后确定地价监测点配置方案。该模式解决了我国当前地价监测体系建立中如何配置监测点这一技术问题。     

运城旱地小麦不同方式地膜覆盖增产效果初报

1996～1997年，在运城市峨嵋岭旱源区以露地常规条播为对照，就地膜平铺全覆盖精量穴播和起垄半覆盖精量条播技术进行了对比研究。结果表明，两种地膜覆盖方式对小麦均有较好的增温和保墒效果，改善了麦苗生态环境，协调了小麦对水热条件的需求，促进了小麦生育进程，延长了幼穗分化和灌浆时间，使单株分蘖成穗、每穗粒数和千粒重均明显优于对照，达到了每亩增产87．3和54．6kg的显著效果。而两种覆盖方式间的效果差异不显著，从而肯定了两种覆盖均不失为旱地小麦实现高产稳产的一项战略性措施。     

农用地估价方法探讨

为合理开发利用我国农用地资源，对农用地的估价方法进行了探讨，研究了根据农用地的价格特点，估价的原则，在确定了农用土地地质量价值、社会保障价值、社会稳定价值、环境价值不同的价值内涵下，如何选择不同的估价方法。     

山地混交林营造技术的研究(Ⅱ)——山地营造混交林的主要混交方式

山地混交林营造技术比较复杂。本试验研究结合立地条件和林分特征,经过10多年的调查研究和试验,提出了8种适用的混交方式,其效果都比较理想,对指导营林生产具有一定意义。     

科尔沁沙地针叶树造林技术研究

研究认为科尔沁沙地针对树育苗适于排水良好的沙质、中性或微酸性土壤，pH值为6．5－7．0，不超过7．5，粘重土质或pH值超过7．5都不适宜。圃地使用草炭或河泥改良土,针叶树苗期管理的重点是防治立枯病；留床切根育苗可提高苗木质量，降低育苗成本；提高针叶树造林成活率的关键是使苗木根系保持湿润，不被风干。采用容器苗造林可以提高造林成活率；幼树越冬，埋上防寒，可提高幼林保存率10％左右。引种针叶树，增加新造林树种，提高针叶树造林技术，改善樟子松林的生长状况，防治枯梢病等对加强科尔沁沙地造林具有重要意义。     

湖州市封山育林林分特征及其效益

浙江省湖州市丘陵地区封山育林7年,按原造林地类型不同,可划分为露岩、荒山和疏林封山类型。作者把封山育林7年的林分与封山育林20年的林分加以对照,论述了各封山类型林分的树种组成、群落结构特征、演替规律和生物产量。实践证明:封山育林是一种成本低、效果好、能迅速恢复森林植被的行之有效的营林手段。     

Effects of Stocking Rate and Overseeding with Red Clover on Productivity of Native Pasture Continuously Grazed by Yearling Steers

Overseeding with red clover (Trifolium pratense L.) and stocking rate are factors that can affect composition and production of hill land pasture. A grazing experiment utilizing yearling beef steers ( Bos taurus) was conducted using 3, 4, and 5 yearling steers ha⁻¹ (285 kg), on native pasture (predominantly Poa pratensis L.) overseeded with red clover and non overseeded. Paddocks of 1 ha were continuously set stocked from mid May to the end of Sept. Herbage mass, herbage consumed and the percentage of legumes, grasses, dead material, and non-leguminous broadleaf plants were recorded. Animals were weighed at the initiation and end of each grazing season and at 4 week intervals. Overseeding increased legume content 4-fold the seeding year but much of this increase was lost the following year. Herbage mass was greater on overseeded pasture the year following seeding but no effect on animal productivity was found. Stocking rate did not affect percentage legume but the proportions of other broadleaf plants increased at high stocking rates. Average daily gain as well as total gain ha⁻¹ was greatest at 4 steers ha⁻¹.     

Spatial Assessment of Land Degradation Risk for the Okavango River Catchment,Southern Africa

The Okavango catchment in southern Africa is subject to environmental as well as socio‐economic transformation processes such as population growth and climate change. The degradation of soil and vegetation by deforestation and overgrazing is one of the downsides of this development, reducing the capacity of the land to provide ecosystem functions and services. In this study, climate simulations are brought together with secondary socioeconomic, pedologic and remote‐sensing data in a GIS‐based assessment of the factors commonly associated with land degradation risk. A high resolution overview is provided for decision‐makers and stakeholders in the region by identifying priority intervention areas where a long‐term decline in ecosystem function and land productivity is most likely to occur. The approach combines 19 risk factors into seven individual ratings for topography, landcover, soil, demography, infrastructure, livestock pressure and climate. These ratings are then weighted and combined into an integrated degradation risk index (DRI). The results show that the land degradation risk is quite heterogeneously distributed in the study area and caused by different factors. Three hot‐spots are identified and compared, one of which is in the far northwestern part of the catchment, one around the local center Rundu and one on the outskirts of the Okavango Delta. We conclude that the approach is suitable to give an overview on degradation risk in the study area, although the classification process is a crucial procedure that should be standardized for further research. Copyright © 2015 John Wiley & Sons, Ltd.     

Towards a Pan‐European Assessment of Land Susceptibility to Wind Erosion

Understanding spatial and temporal patterns in land susceptibility to wind erosion is essential to design effective management strategies to control land degradation. The knowledge about the land surface susceptible to wind erosion in European contexts shows significant gaps. The lack of researches, particularly at the landscape to regional scales, prevents national and European institutions from taking actions aimed at an effective mitigating of land degradation. This study provides a preliminary pan‐European assessment that delineates the spatial patterns of land susceptibility to wind erosion and lays the groundwork for future modelling activities. An Index of Land Susceptibility to Wind Erosion (ILSWE) was created by combining spatiotemporal variations of the most influential wind erosion factors (i.e. climatic erosivity, soil erodibility, vegetation cover and landscape roughness). The sensitivity of each input factor was ranked according to fuzzy logic techniques. State‐of‐the‐art findings within the literature on soil erodibility and land susceptibility were used to evaluate the outcomes of the proposed modelling activity. Results show that the approach is suitable for integrating wind erosion information and environmental factors. Within the 34 European countries under investigation, moderate and high levels of land susceptibility to wind erosion were predicted, ranging from 25·8 to 13·0 M ha, respectively (corresponding to 5·3 and 2·9% of total area). New insights into the geography of wind erosion susceptibility in Europe were obtained and provide a solid basis for further investigations into the spatial variability and susceptibility of land to wind erosion across Europe. © 2014 The Authors. Land Degradation and Development published by John Wiley & Sons, Ltd.