专业户荟萃

专业户荟萃龙南县南亨乡夹水村中拖驾驶员张石成，选准治理荒山水土流失，发展果业致富这条路，从１９８３年起，全家苦战４个春秋，按水土保持技术要求，高标准种植柑桔１０００株。１９８７年以来，年平均产桔１．５万公斤，纯收入１万余元。与此同时，张石成积极开展多...     

Sero-prevalences of selected cattle diseases in the Kafue flats of Zambia

Sera from five traditionally managed herds grazing in the Kafue flats were tested for antibodies to bovine viral diarrhoea-mucosal disease (BVD-MD), parainfluenza 3 (PI3), infectious bovine rhinotracheitis-infectious pustular vulvovaginitis (IBR-IPV), bovine adenovirus 3 (BAV3) and Bluetongue (BT). The sero-prevalences of the first four diseases were respectively 76.2, 94.4, 42.1 and 87.4%. Five samples (2.3%) gave doubtful reactions for BT. Prevalences of 28.5% for brucellosis, 14% for Rift Valley fever (RFV), 0.9% for Q fever and 11.2% for chlamydiosis were also recorded. Significantly higher values for BVD-MD (p<0.005), IBR-IPV (p<0.01) and brucellosis (p<0.05) were found in animals over 1 year of age. No differences were recorded between herds or between male and female animals.The high concentration of wild and domestic ruminants grazing together in the flood plains during the dry season may be a major determinant of the high values observed. Traditional farmers, slaughterhouse workers and other people involved in livestock production are particularly at risk of contracting brucellosis and RVF because of the high prevalences in cattle and local habits favourable to their transmission.     

澜沧江流域景东段造林模式分析

介绍澜沧江流域景东段泡核桃经济林、思茅松用材林、紫胶寄主经济林3种造林模式,分析了取得的成果和经验及存在的问题.提出统筹规划、协调发展、提高土地产出效率、扶持龙头企业、创地方品牌等建议.     

Insecticides applied to soil of transplant plugs for Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae) management in broccoli

Chemical control with insecticides, typically applied as foliar sprays or chemigation, is the primary tactic used to manage Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae). We evaluated the efficacy of 14 insecticides, including both systemic and non-systemic insecticides, against B. hilaris applied as a seedling tray drench. Experiments were conducted in both greenhouse and field settings. In all experiments, we used the maximum label rate of insecticides and calculated dose per seedling based on this rate and standard plant density per hectare. Each seedling in the tray received 2-mL insecticide solution, and the seedlings were then exposed to B. hilaris adults after transplanting in cages for greenhouse experiments or natural B. hilaris populations in the field experiments. A scale system (0–4) was used to evaluate the severity of B. hilaris feeding injury on leaves where 0 = no injury and 4 = >75% of the leaf margins with B. hilaris feeding injury. We evaluated damage using the rating system, percentage of damaged leaves, number of feeding injury sites, as well as plant height, leaf width, and fresh and dry weight. In the greenhouse experiment, percentage of injured leaves, number of injury sites, and damage rating were significantly lower for transplants treated with acetamiprid, clothianidin, dinotefuran, imidacloprid, and thiamethoxam, and cyclaniliprole compared with the untreated. There was a relationship between feeding injury sites and plant height, leaf width, fresh and dry weight (R² > 0.5) in both 2015 field experiments. Similarly, the transplants treated with acetamiprid, clothianidin, dinotefuran, imidacloprid, thiamethoxam, thiamethoxam + chlorantraniliprole, imidacloprid + β-cyfluthrin and cyclaniliprole had significantly lower damage ratings than those treated with chlorpyrifos, bifenthrin, tolfenpyrad, flonicamid, cyantraniliprole, spinetoram and the untreated control. For transplanted broccoli, treatment of transplant plugs with neonicotinoid insecticides prior to planting can be an effective method for controlling B. hilaris.     

Landscape hierarchies influence riparian ground-flora communities in Wisconsin, USA

We examined the distribution of ground-flora species (herbaceous and woody species <1 m tall) across riparian areas of northeastern Wisconsin in an effort to understand how hierarchical landscape properties, such as the physiographic system (ground moraine and outwash plain), valley system (constrained and unconstrained), and valley floor landforms influence distribution patterns of ground-flora species and functional plant guilds across riparian areas of small streams and rivers in a glacial landscape. A total of 162 species were recorded on 417 (1 m²) plots stratified by four different valley types that reflect the dominant physiographic system and valley system (constrained ground moraine, constrained outwash plain, unconstrained ground moraine, unconstrained outwash plain) and transverse geomorphic structure (valley floor landforms including floodplains, terraces, slopes, and adjacent uplands). Although distribution patterns of individual ground-flora species are highly variable among the four valley types, canonical correspondence analyses (CCA) of individual valley types indicate that ground-flora vegetation is related strongly to hierarchical landscape properties, including valley type and the transverse geomorphic structure of the stream valley. Vegetation ultimately reflects the influence of hydrogeomorphic processes that shape valley floor landforms. Constrained valley types tend to be characterized by diverse floodplain ground-flora communities dominated by graminoids and pteridophytes, while the terraces and slope plant communities are comprised of facultative upland and obligate upland perennial forb and woody species whose distribution appears to be a function of topographic features, such as aspect. However, ground-flora communities of unconstrained valley types appear to be responding not only to changes associated with the transverse geomorphic structure of the riparian ecotone, but also to more localized changes in environmental conditions associated with flooding and hydrologic regime. As a result, floodplain, terrace, and slope ground-flora communities tend to be diverse, dominated by a mixture of obligate wetland, facultative wetland, and facultative species. Thus, variation in riparian plant community characteristics can be explained using a nested, hierarchical landscape framework to organize and group different riparian settings based on the underlying geomorphic processes shaping stream valleys. Based on these results, we suggest that riparian management zones (RMZs) designed to maintain riparian function should be variable in width rather than fixed, encompassing variation in valley floor landforms and valley walls, regardless of the physiographic system.     

沟谷型观光农业园区规划——以九鼎山生态农庄为例

在济南东部山区九鼎山生态农庄规划实践的基础上,提出沟谷型观光农业园区的概念及其规划思路,从园区定位、园区总体布局、景观规划、项目规划、设施规划等方面对沟谷型观光农业园区进行了深入探讨,并结合九鼎山生态农庄规划实践进行例证,最后总结了沟谷型观光农业园区规划应注意的问题,以期指导沟谷型观光农业园区的规划。     

绵阳官溪河流域防护林林木分化及异常木分布格局

对绵阳官溪河流域常见的几种防护林类型林木分化及异常木分布格局进行了研究。结果表明，防护林林木分化的结果以小径木占优势，尤以直径1cm～6cm的个体最多，占林分总个体数的60％以上。桤柏混交林、柏木纯林、松栎混交林、松柏混交林和松柏栎混交林的林木株数按径阶的分布表现出左偏态分布，直径大小的变异性较低；与之相比。栎黄荆次生灌丛和马尾松林不呈偏正态分布，直径大小的变异性较高。异常木直径主要分布在1cm～10cm范围内，其中倾斜木和倒伏木超过了异常木总数的50％，枯立木和濒死木中，马尾松林和松柏栎混交林较其它防护林类型少。异常木的分布格局除松柏栎混交林呈随机分布外，其余的皆呈聚集分布，但聚集强度不大。异常木聚集强度的大小与取样面积大小的关系表现为：Kuno．E．聚集度指标值（G）随取样面积的增大，由小变大，而Lloyd．M．平均拥挤度值（m^＊）则由大变小。     

四川西部干旱河谷自然特征及植被恢复与重建途径

本文分析阐明了四川西部干旱河谷的特点、形成及其发展趋势,对干旱河谷生境进行了分类,并针对各类型或亚类型提出了植被恢复与重建的途径、方法及其配置的植物种类,同时提出了今后需要解决的问题及研究的课题。     

近百年来金沙江河谷地貌研究进展及其趋势

简要回顾近百年来金沙江河谷地貌研究的历程,从长江第一湾、阶地、河谷堆积体、水系演化、河槽地貌几个方面归纳金沙江河谷地貌相关研究和实践进展,并在此基础上进一步探讨金沙江河谷地貌研究的新趋向:即对河谷地貌学理论研究的促进、河谷地貌实验和定量化的研究、河谷地貌区生态系统研究、流域地貌系统的研究。