母牛不孕症的中西医结合治疗

通过采用中西医结合的办法,对张掖市百万头肉牛基地母牛不孕症开展治疗,取得显著效果。母牛不孕症发病率逐渐降低,为百万头肉牛基地可持续发展创造了有利条件。     

Introduction: Working Forests in the Tropics: Policy and Market Impacts on Conservation and Management

Abstract

Tropical forests are very rich in biological diversity and form an important economic and ecological resource. This biodiversity is of great value for communities living in or near these forests as a ready source of subsistence and cash income, and for the world at large as a source of tropical timber and non-timber products and a repository of genetic and chemical information. However, this biological complexity is diminishing rapidly. We analyze the main human (anthropogenic) actions causing loss of tropical forest biodiversity along with the strategies of management for forest biodiversity. Not only is the biophysical component important in management for biodiversity, but the active participation and support of local people, national governments, and the international community as a whole are essential to effective and sustainable development of tropical forests. This development strategy ensures that socioeconomic and environmental benefits are provided for present and future generations.     

Regional Conservation in the Virunga-Bwindi Region

SUMMARY

Bwindi Impenetrable National Park and the Virunga Volcano region are the last remaining habitats of the highly endangered mountain gorilla (Gorilla beringei beringei). This conservation area, shared by Uganda, Rwanda and the Democratic Republic of Congo, also acts as a refuge for biodiversity and high endemism in the Albertine Rift of Central East Africa. This particular region has suffered from a number of years of civil strife, which have severely affected the management of these forests. This paper will explore the experiences of the International Gorilla Conservation Programme (IGCP) obtained throughout the development of regional processes that are working towards establishing a transboundary-protected area. The establishment of a regional framework and tools utilized are described. The costs and constraints incurred by the IGCP and the resulting positive impacts on conservation are also highlighted.     

Growth and Nutritional Responses of Juvenile Jeffrey Pine to Post-Planting Fertilization

Abstract

Broadcast fertilization of a three-year-old Jeffrey pine (Pinus jeffreyi Grev. & Balf.) plantation growing on an eroded Sierra Nevada site was examined for its capacity to enhance seedling growth. The amendments chosen for the study included controlled release and conventional soluble formulations that contained a variety of N forms, but all featured high N content along with other nutrients. Four application rates were used, and all amendments were distributed around the base of the seedlings as top dressing. Four seasons after treatment application, fertilized seedlings were 129% larger in height, 93% larger in diameter, and 865% greater in shoot volume than unfertilized seedlings overall. Seedling sizes generally increased with application rate, and by a small margin, the controlled release fertilizer outperformed the other formulations. Relative growth analysis suggested that stimulation by the amendments would continue beyond four seasons. Foliar analysis conducted early and again late during the study revealed that N and P concentrations were consistently raised by fertilization, which likely accounts for much of the accompanying growth gains, while Ca, Fe, Mn, B, and Al concentrations were consistently reduced. Either early or late, foliar K was also raised while Mg, S, Zn, and Cu were reduced. Collectively, these results indicate that fertilization with a variety of high N formulations can increase the availability and uptake of critical nutrients sufficiently to impart in Jeffrey pine on low quality sites a substantial growth advantage.     

浅谈西部环境法律体系建设与完善

指出了为适应深入实施西部大开发的发展战略,加强西部地区的生态建设,要求建立与完善与其相适应的环境法律法规。从西部环境保护的法律体系现状出发,分析了现有环保法律体系的不足。同时,从自然和社会两方面提出了完善现在法律体系的措施,并强调了国家机关、社会组织、公民的监督的作用。     

鄂西烟草种植区气象灾害的时空变化分析

为明确气候变化对鄂西烟草气象灾害危险性的影响,基于已建立的干旱、低温冷害、连阴雨、暴雨、高温热害的危险性指标体系,利用鄂西18个国家气象站观测数据开展近60年来烟草高影响气象灾害的危险性指数分析,并进行前30 a和后30 a的对比。结果表明,从时间维度看,后30 a鄂西烟草种植区干旱、连阴雨和暴雨危险性总体有所减轻;而鄂西南干旱危险性加重,水分条件逐渐成为影响当地烟叶生产的主要因子之一。在气候变暖背景下,低温冷害和高温热害的危险性分别呈现出部分减轻和普遍加重的趋势。分区域来看,枣阳、南漳等地持续受干旱影响,低温冷害集中在高海拔地区,高温热害则分布于河谷地带。五峰、兴山是冰雹、大风的相对高发中心,需防范强对流天气带来的危害。鄂西地区由于地理位置不同,影响烟叶生产的主要气象灾害及气候变化有所差异。从综合气象灾害危险性分布来看,除巴东北部、建始北部局地外,后30 a恩施大部分地区气象灾害综合危险性等级仍在“中等”及以上,以鹤峰最为严重。     

辽西油松2种造林方式水土保持效果的研究

辽西地区气候干旱少雨,水土流失严重。植树造林是改善地表植被状况和提高土壤质量的一项基础性工作。本试验以油松种子和容器苗为材料,采用直播和容器苗造林进行试验,开展土壤水土保持效果研究。结果表明,2种造林方式改善土壤植被效果显著,林木生长以容器造林效果最好。对土壤理化性质方面,造林后土壤理化性质显著提升,2种造林方式除了土壤有机质含量外,其他处理没有差异。直播造林的水分保持效果显著高于容器造林。     

辽西山地丘陵区风电场项目防治水土流失措施

以大唐葫芦岛兴城围屏风电场项目为例,根据辽西山地丘陵区风电场水土流失的特点,阐述项目的具体组成和防治分区,提出各防治分区的水土流失防治措施,为山地丘陵区风电场项目防治水土流失提供借鉴和经验。     

我国内蒙古西部地区国有林场经营现状与发展问题探析

国有林场在内蒙古林业生态建设中具有骨架作用,是祖国生态安全屏障的重要组成部分与支撑点,也是贯彻落实生态文明建设,践行“绿水青山就是金山银山”理念不可或缺的重要实施主体。在深入了解与掌握内蒙古自治区西部地区6个市国有林场经营现状的基础上,总结归纳了内蒙古西部地区国有林场经营的特点,深入分析了内蒙古西部地区国有林场面临的问题与困境,并探讨解决这些问题的途径,为国有林场今后的发展提出了合理化建议。