甘州区规模化羊场主要疫病及防控措施探讨

肉羊养殖逐渐向规模化方向发展,但是口蹄疫、小反刍兽疫、羊布病等疫病防控面临形势愈加严重。需要从羊场设计、加强饲养管理、消毒、驱虫、制定合理免疫程序加强防检疫工作等多方面采取综合防控措施,降低疫病风险,取得最大养殖效益。     

Impact of the COVID-19 pandemic on agricultural exports

The COVID-19 outbreak has shocked the world's economies in the year of 2020. As this pandemic spreads around the globe, many experts feared that the global food supplies might start running short, especially if supply chains were disrupted. COVID-19 also added to the uncertainty of the business operation. Therefore, it is critical to understand how COVID-19 pandemic affected global food supply and market. In this study, we investigate the impact of COVID-19 on agricultural export companies in China using a unique firm-level survey data. We found that although on average agricultural businesses experienced declines in the exports, exports of some agricultural products especially grain and oil held strong and even increased, implying the essential demand for staple food during the pandemic. Not surprisingly, exports of medicinal herb also increased significantly during the pandemic. However, exports of goods such as edible fungus and horticultural products sharply decreased. Our results also showed that in general, impact of COVID-19 on smaller firms was more severe than that on larger firms. The results of this study can provide useful guidance and implications for agricultural businesses and policy makers on their COVID-19 mitigation efforts to navigate this global pandemic.     

麻山药种植田沙壤土流动性离散元模型颗粒放尺效应

为简化麻山药-沙壤土复合体离散元模型，提高离散单元法在农业领域中的计算效率，以沙壤土为研究对象，在EDEM离散元软件中构建非球形颗粒，进行双目标参数标定试验，采用放大颗粒粒径方法，利用转鼓、坍塌与FT4流变仿真试验，从颗粒群动态堆积角、流动质量、流动速率以及能量等方面探究了颗粒放尺效应对颗粒群物理特性的影响。试验结果表明：干燥处理后的2 mm粒径沙壤土基质静态堆积角和动态堆积角平均值分别为32.16°和35.02°；与独立标定试验相比，双目标标定试验获得的仿真参数更具准确性与唯一性；在动态堆积角试验中，真实沙壤土颗粒在转鼓中所形成的动态堆积角随粒径和旋转速度的增大而减小，而在仿真试验中，转鼓转速相同情况下，非球形颗粒群在增大粒径的情况下所产生的动态休止角差异较小；坍塌试验中，不同粒径颗粒群在流动过程中的流动质量与平均流速变化趋势基本一致，但误差随粒径增大而增大；颗粒质量相同时，将粒径分别放大2倍及4倍，颗粒数量同比减少87.24%、98.92%，仿真时间明显缩短，计算效率显著提高；FT4流变试验表明，当放尺因子S为2时，阻力FV及其力矩T随时间变化的拟合曲线值约为原尺时的2倍，而当放尺因子S为4时，与原尺相比，拟合曲线斜率差异显著，相关性明显降低。研究结果可为构建沙壤土离散元放尺模型提供理论依据，同时也可为农业工程离散元放尺仿真计算提供一定参考。     

畜禽产品水足迹研究进展

畜禽产品的生产过程需要消耗大量水资源,对畜禽产品进行水足迹评价能够清楚地认识其对水资源的消耗情况。目前,人们对畜禽产品的需求日益增长,水资源消耗也在持续升高,因此研究如何缓解畜禽产品生产带来的水资源压力,已成为人们必须要面对的问题。评价畜禽产品的用水量和对不同生产阶段的用水分析,将有助于生产者和消费者确定用水量最大的过程,并针对性地实施提高用水效率的战略。本文介绍了国内外畜禽产品水足迹研究现状,对比分析了不同畜禽产品水足迹评价方法,展望了畜禽产品水足迹的发展,最终提出以下降低畜禽产品水足迹的主要措施:1)减少饲料生产的水足迹;2)提高饲料转化率;3)水资源管理和提高畜禽动物生产性能;4)改变人们的消费习惯。     

规模养殖场畜禽粪污处理和资源化利用

畜牧作为推动农业发展的动力,可促进其发展现代化农业,提高农民收入。但是,随着畜牧业发展,加剧粪污污染问题,应加强粪污处理及资源化利用,以达到保护环境的目的。该文主要从畜禽粪污处理和资源化利用重要性切入,分析目前粪污处理与资源化利用方式,提出相应保障措施,进而推动畜牧业实现绿色发展。     

Assessing spillover from marine protected areas and its drivers: A meta‐analytical approach

Overfishing may seriously impact fish populations and ecosystems. Marine protected areas (MPAs) are key tools for biodiversity conservation and fisheries management, yet the fisheries benefits remain debateable. Many MPAs include a fully protected area (FPA), restricting all activities, within a partially protected area (PPA) where potentially sustainable activities are permitted. An effective tool for biodiversity conservation, FPAs, can sustain local fisheries via spillover, that is the outward export of individuals from FPAs. Spillover refers to both: “ecological spillover”: outward net emigration of juveniles, subadults and/or adults from the FPA; and “fishery spillover”: the fraction of ecological spillover that directly benefits fishery yields and revenues through fishable biomass. Yet, how common is spillover remains controversial. We present a meta‐analysis of a unique global database covering 23 FPAs worldwide, using published literature and purposely collected field data, to assess the capacity of FPAs to export biomass and whether this response was mediated by specific FPA features (e.g. size, age) or species characteristics (e.g. mobility, economic value). Results show fish biomass and abundance outside FPAs was higher: (a) in locations close to FPA borders (<200 m) than further away (>200 m); (b) for species with a high commercial value; and (c) in the presence of PPA surrounding the FPA. Spillover was slightly higher in FPAs that were larger and older and for more mobile species. Based on the broadest data set compiled to date on marine species ecological spillover beyond FPAs' borders, our work highlights elements that could guide strategies to enhance local fishery management using MPAs.     

Dynamics of Integration between Chinese and International Waste Paper Markets

ABSTRACT

China is the largest importer of waste paper in the world and is highly dependent on the international market. Thus, the relationship between Chinese and international waste paper markets affects the supply of fiber materials in China’s paper industry. This study examined the dynamic relationship between the two markets and the impact of newly implemented policies on both markets. We used unit root tests, cointegration test, vector error correction model (VECM) and frequency-domain Granger causality test to investigate the integration between Chinese and international waste paper markets and identify which of the two markets is the price leader. The results revealed that the two markets were integrated after controlling for structural breaks, and the Chinese market acted as the price leader. Since the supply of waste paper and wood pulp is insufficient in China to meet the fiber demand of the paper industry, waste paper import restrictions have significantly affected the supply of fiber materials in China’s paper industry. Therefore, the Chinese government should fully consider the benefit of market integration and make full use of international waste paper resources to satisfy the large domestic demand for paper products.     

规模化猪舍废气复合净化系统设计与试验

为解决规模化猪舍废气排放造成的环境污染问题，设计了一种猪舍废气复合净化系统。该系统采用化学法与水洗法相结合，通过PLC（可编程逻辑控制器）控制系统实时采集净化系统内的pH值、电导率、液位和压差等动态环境数据，智能控制洗涤泵启停和电磁阀通断，自动完成供水、加酸、喷淋和排废4个工作环节。同时，控制系统采用MCGS触摸屏与PLC建立通讯，通过创建人机交互界面实现系统环境数据监测、运行状态流动显示、按需配置系统参数和报警信息输出等多种功能，实现了系统操作的人性化和过程的可视化。系统可根据实际应用中对净化效率和运行成本的要求，实现多种控制模式，均有效抑制了猪舍废气排放。试验结果表明，系统对主要污染成分氨气的平均去除率可达到85%，整体运行可靠、控制简单，经济成本量化清晰。该系统在江西某种猪场实施应用，成效显著，可为畜禽养殖环境废气净化处理的工程应用提供参考。     

电商环境下新中式木家具外贸市场分析

随着全球电子商务蓬勃发展,新中式木家具突破传统的国内营销环境,在“一带一路”沿线国家提高外贸市场占有率越来越重要。简述了电商环境与传统营销环境异同点,对新中式木家具外贸市场进行初步研判,提出了拓展电商环境下新中式木家具外贸市场措施。