The role of CITES in the conservation of marine fishes subject to international trade

All possible tools need to be marshalled for marine fish conservation. Yet controversy has swirled around what role, if any, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) should play for marine fishes. This paper analyses the relevance and applicability of CITES as a complementary tool for fisheries management. CITES currently regulates the international trade of very few marine fish species, by listing them in its Appendices. After the first meeting of the Parties (member countries) in 1976, no new marine fish taxa were added to the CITES Appendices until 2002, when Parties agreed to act to ensure sustainable and legal international trade in seahorses (Hippocampus spp.) and two species of sharks. Progress has continued haltingly, adding only one more shark, humphead wrasse (Cheilinus undulatus) and sawfishes by 2012. Parties voice concerns that may include inadequate data, applicability of CITES listing criteria, roles of national fisheries agencies, enforcement challenges, CITES' lack of experience with marine fishes, and/or identification and by‐catch problems. A common query is the relationship between CITES and other international agreements. Yet all these arguments can be countered, revealing CITES to be a relevant and appropriate instrument for promoting sound marine fisheries management. In reality, Parties that cannot implement CITES effectively for marine fishes will also need help to manage their fisheries sustainably. CITES action complements and supports other international fisheries management measures. As CITES engages with more marine fish listings, there will be greater scope to analyse its effectiveness in supporting different taxa in different contexts.     

抚育间伐技术目标管理新方法

本文利用林层结构划分条件、林分起源、林层年龄、树种组成等因子,将松江河林区的幼、中龄林划分为四个林相组和九个林相类型。在此基础上编制了幼、中龄林林相类型表。用该表能指导幼、中龄林的调查、设计和抚育间伐。该目标管理技术环节易于掌握,并可提高抚育质量。     

海南岛热带天然林可持续经营单位、标准和指标及采伐作业的研究

具有“地球之肺”之称的热带森林,长期以来,只用来采伐木材和开垦农田等,使得热带森林尤其是热带天然林面积不断减少,质量不断降低。根据联合国粮农组织《１９９１年生产年鉴》资料,从１９８０～１９９０年,热带地区森林减少９％。全球濒临灭绝的有花植物为１万种,...     

Watershed Health Characterization Using Reliability–Resilience–Vulnerability Conceptual Framework Based on Hydrological Responses

An attempt was made to employ the reliability (R_el)–resilience (R_es)–vulnerability (V_ul) conceptual framework to develop a typical indicator system for quantitative assessment of watershed health. The study aimed to conceptualize and customize the R_elR_esV_ul framework to watershed health assessment for the Shazand Watershed in Markazi Province, Iran, for the period of 1977–2014. To this end, four easily, reliable, available and accessible criteria viz. standardized precipitation index (SPI), low and high flow discharges (LFD and HFD), and suspended sediment concentration (SSC) were selected, and corresponding indices for reliability–resilience–vulnerability (R_elR_esV_ul) framework were accordingly conceptualized and calculated. The thresholds of 0.1, 0.16 m³ s⁻¹, 12.63 m³ s⁻¹ and 25 mg l⁻¹ day⁻¹ were thus selected for SPI, LFD, HFD and SSC, respectively. The results showed a decreasing trend in R_el and R_es, and an increasing trend in V_ul for SPI and LFD in the Shazand Watershed. The results further showed an increasing trend in R_el, and a decreasing trend in V_ul for HFD and SSC. A decreasing trend was ultimately recognized in watershed health index for all criteria except SSC. Additionally, the integrated hydrological watershed health index of 0.16 ± 0.11 obtained from the geometric mean of the R_elR_esV_ul framework indices also showed a decreasing trend for the Shazand Watershed health during the study period. The results of the present initiative study can be considered as a baseline by decision makers and managers to effectively adjust watershed management strategies to handle land degradation issues in the area. Copyright © 2016 John Wiley & Sons, Ltd.     

Response of labile organic C and N pools to plastic film removal from semiarid farmland soil

To examine the effects of plastic film removal on grain yield and soil organic matter (SOM), a spring maize (Zea may L.) field experiment was conducted for 5 yr at Changwu Agricultural and Ecological Experimental Station of Northwest China. Compared with traditional plastic film mulching during entire growing stages (FM), plastic film removal at the silking stage (RM) resulted in a 6.3% higher average maize yield. Under the RM treatment, soil organic carbon and total nitrogen significantly increased after the 5‐yr cultivation in the 0‐ to 20‐cm layer. Significant increases in extractable organic C (EOC), KMnO₄‐oxidizable C (KMnO₄‐C) and C management index (CMI) in the 0‐ to 20‐cm layer, and light fraction organic C and EOC in the 20‐ to 40‐cm layer were observed in response to plastic film removal after the 1‐yr treatment; the responses were more significant after 5 yr. Under the RM treatment, significant increases in microbial biomass C, light fraction organic N, extractable organic N, KMnO₄‐C and CMI were also observed after five years in the 20‐ to 40‐cm layer. Moreover, KMnO₄‐C and EOC were much more sensitive than other labile SOM fractions to the application of RM, even after only 1 yr of cultivation. Therefore, compared with mulching for the whole growing season, plastic film removal at the maize silking stage is an effective option for increasing yields and enhancing SOM concentration and soil sustainability in the regions with semiarid monsoon climates that have sufficient rainfall during maize reproductive stages.     

Main experiences on design and management of the Dujiangyan irrigation system

The largescale Dujiangyan Irrigation System has had a long history. Built some 2200 years ago, it still operates smoothly today. Two major causes for the obvious profits it has provided are:Firstly, Yuzui (a bifurcation pier), Feishayan (a sand outlet and spillway) and Baopingkou (a diversion intake for the general trunk canal), the three main head-works were built in accordance with the terrain and topography of the river and appropriately arranged, thus successfully solving the problem of sand discharge and flood control. Consequently the task of gravity diversion could be fulfilled over a long period.Secondly, there is a special management and maintenance system, which is made up of a technical and an administrative department. The former is in charge of the maintenance and drawing-up of flood control and water consuming plans. The latter is responsible to mobilize and organize farmers which benefit from the system to carry out related plans and tasks. The most apparent characteristics of management is that many farmers are organized to participate in the management of this irrigation system. At present, techniques like remote control and telemetery have been adopted. Also experiments on management automation and optimization of water allocation are being conducted.     

广东省碳汇林经营风险因素分析

在种植碳汇林增加森林碳汇成为当前全球应对气候变化重要途径之一的大背景下,通过阐述广东省碳 汇林的经营现状,根据碳汇林营造时期、经营时期以及后期市场交易的特点,将广东省碳汇林经营主体在经营时所 面临的风险总结为环境、过程和市场三大类,并加以分析,从而提出了风险控制对策院加大宣传力度,在碳汇林经营 中实现经营主体与农户双赢;增加保险投入,加强技术创新;扩充融资渠道,保障碳汇林顺利经营;完善碳汇信息平 台,建立健全碳汇市场交易制度。     

Web环境下用户管理系统的设计与实现

简单描述了Web数据库技术的发展及近来飞速发展的技术,介绍了后台信息发布的相关知识,结合一些程序重点说明了系统用户管理的结构及功能,提出了一些相关看法和见解.     

Nitrogen and Irrigation Management Practices to Improve Nitrogen Uptake Efficiency and Minimize Leaching Losses

Summary

Nitrogen (N) is the most important nutrient for plant growth and production. Nitrogen uptake efficiency is dependent on a number of factors. Water management influences the transformation of N sources applied to the soil and transport of the nitrate form of N in the soil. Nitrate-N is the final product of N transformations and is quite mobile in soils with the water front. Leaching of nitrate below the rootzone is an economic loss and contributes to non-point source pollution of groundwater. In this chapter we summarize the factors influencing the N uptake efficiencies for various crops and production systems, and chemical and biological processes that influence the N transformation or losses. Recent advances leading to development of N and irrigation best management practices that support sustainable crop production and net returns while minimizing the non-point source nitrate pollution of ground-water are also discussed.     

机械插秧密度和氮肥运筹对两优1528群体动态和产量的影响

研究了机插条件下不同的栽植密度、氮肥使用量和氮肥中基、蘖、穗肥不同的用量比例对两系杂交水稻两优1528群体动态、产量构成以及生育进程.结果表明,两优1528分别在机插密度为24.0万穴/hm2、氮肥用量247.5 kg/hm2以及基、蘖、穗肥比例为5:3:2时产量最高.栽植密度过大,无效分蘖增多,每穗总粒数减少,密度过小则群体总量较小,有效穗不足;氮肥用量达247.5 kg/hm2时虽然产量最高,但氮肥偏生产力(PPN)较低,而氮肥用量202.5 kg/hm2可获得较高的产量和氮肥偏生产力.