Transforming the Loess Plateau of China

This paper aims to show the importance of land consolidation in transforming the Loess Plateau of China. The paper comprehensively analyzes how over recent decades the Grain for Green Project and Gully Land Consolidation Project jointly transformed the ecology and landscape of the Loess Plateau and the livelihood of its residents. The findings show that these two projects have achieved a balance between green protection, new land creation, and improved food security and livelihood of local people in the hilly areas of China. The paper points out that the successful transformation of the Plateau lies in a holistic approach incorporating various components of the human and natural systems. Finally, the paper highlights the necessity of retaining these two land consolidation projects as part of an ongoing policy in the mountain and hilly areas of China, changing agricultural management to suit the new relationship between humans and the land.     

Securing African forests for future drier climates: applying ecophysiology in tree improvement

Increasing incidences of drought-induced tree mortality are being recorded worldwide, including Africa. African forests cover a significant proportion of the continent, which implies that African forest sustainability is threatened from a climate-change perspective. This is especially problematic in a developing nation context, because forest ecosystems such as plantation forestry provide important goods and services that sustain human well-being and economic growth. Disentangling the likely triggers of tree mortality (including those linked to drought) in landscapes would not only explain the mechanisms underlying local die-offs, but also better predict future mortality events. Methods applied in the field of ecophysiology are particularly useful to study in situ plant responses to an environment. We consider the status quo of global peer-reviewed publication outputs during the past century that have made use of key ecophysiological research approaches, specifically studies concerning ‘tree xylem anatomy’, ‘tree xylem cavitation’, ‘tree leaf gas-exchange’ and ‘tree xylem hydraulic conductivity’. We highlight the growth and applicability of this research field in understanding tree ecology. We also assess the role that the forestry sector has had in promoting such research to ensure future-proof forest products. Most importantly, we consider how Africa with its vast forested landscapes fits within this research spectrum. The last decade saw an increase of up to 60% in the total number of articles published, particularly with a focus on tree xylem cavitation and conductivity. Although forest research contributed greatly to the global tally of ecophysiological studies, and such studies in Africa have also increased by up to 88% in the past decade, there remains a general lack of this research topic in the continent. It is clear an optimisation of applied ecophysiological concepts and techniques will promote an improved understanding of tree mortality patterns. We argue that ecophysiological data will be crucial to future-proof tree improvement strategies in African commodity production landscapes, especially given future drier climates.     

海南省淮山产业发展现状及可持续性分析

海南省作为热带地区具有发展淮山产业的独特优势,海南淮山逐渐成为振兴农村经济、使农民脱贫致富的一个重要产业。海南淮山产业在发展的同时也存在病虫害发生严重、栽培及采收技术相对落后、缺乏产品深加工的企业和技术等问题,束缚了产业的快速发展。通过调查分析,本文提出扩大宣传、提升品牌效应、选育新品种、改进栽培技术、大力发展产品深加工等产业可持续发展措施。     

Replacing fish oil and astaxanthin by microalgal sources produced different metabolic responses in juvenile rainbow trout fed 2 types of practical diets

Dietary fish oil supplementation provides n-3 long-chained polyunsaturated fatty acids for supporting fish growth and metabolism and enriching fillet with eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; c22:6n-3). Two experiments were performed as a 3 × 2 factorial arrangement of dietary treatments for 16 wk to determine effects and mechanisms of replacing 0%, 50%, and 100% fish oil with DHA-rich microalgae in combination with synthetic vs. microalgal source of astaxanthin in plant protein meal (PM)- or fishmeal (FM)- based diets for juvenile rainbow trout (Oncorhynchus mykiss). Fish (22 ± 0.26 g) were stocked at 17/tank and 3 tanks/diet. The 100% fish oil replacement impaired (P < 0.0001) growth performance, dietary protein and energy utilization, body indices, and tissue accumulation of DHA and EPA in both diet series. The impairments were associated (P < 0.05) with upregulation of hepatic gene expression related to growth (ghr1and igf1) and biosynthesis of DHA and EPA (fads6 and evol5) that was more dramatic in the FM than PM diet-fed fish, and more pronounced on tissue EPA than DHA concentrations. The source of astaxanthin exerted interaction effects with the fish oil replacement on several measures including muscle total cholesterol concentrations. In conclusion, replacing fish oil by the DHA-rich microalgae produced more negative metabolic responses than the substitution of synthetic astaxanthin by the microalgal source in juvenile rainbow trout fed 2 types of practical diets.     

沿河县耕地生产潜力及人口承载力

以沿河县为例,运用逆向因子修正法研究耕地生产潜力,并运用灰色模型对耕地、粮食产量、人口进行预测,进而对该县耕地资源承载力进行评价.结果表明,沿河县耕地生产潜力仍有46.27%可供利用,潜力较大;结合温饱型、宽裕型、小康型及富裕型这4种生活类型所需的营养结构,通过承载率比的计算,2010年、2020年沿河县耕地资源人口承载力达到小康型水平,富裕型在现有生产条件下较难实现.     

冯家山水库供水持续性评价

结合可持续发展理念与风险分析的理论和方法,选取可靠性、弹性、脆弱性、均方差及最大缺水率等5个性能指标为持续性指标,以冯家山水库为研究对象,针对生活、工业、生态环境、农业灌溉等水库用水户,合理选取性能指标构建持续性指标,对其持续性进行了评价;并用这4个用水户作为用水群的组成构建群持续性指标对水库供水持续性进行了评价.冯家山水库供水持续性评价结果表明,在现状情形下,水库供水持续性为35%,持续性较低;尤其农业灌溉供水持续性仅为29%.减少农业灌溉对水库需水要求的30%时,生活、工业、生态环境、农业灌溉用水户的可靠性及持续性都得到提高,此时,农业灌溉供水持续性为40%,水库供水持续性为45%,水库供水持续性得到提高.可在灌区采取一定的节水措施,以减少农业灌溉对水库的需水,提高农业灌溉用水户的持续性和水库供水持续性,降低缺水风险,促进水库的可持续发展.     

生态供需规律探析

文中首先辨析"可持续"和"可持续发展"2个不同概念; 提出了生态需求和生态供给的概念, 认为生态需求分为公共生态需求和私人生态需求, 生态供给分为公共生态供给和私人生态供给; 分析了生态需求和生态供给的变动规律, 认为其各自分别有量的变动以及生态需求或供给的变动2种情况; 讨论了生态供求平衡的规律, 包括生态供求变化的基本趋势和生态供求平衡的调整; 最后指出:1)满足私人生态需求必须依靠以私人投入为主、政府投入为辅的市场调节机制, 满足公共生态需求则必须依靠以政府投入为主、私人投入为辅来实现; 2)增加生态供给有外延扩张和内涵扩展2种形式, 努力提高生态经济产品的价值内涵是扩大生态产品有效供给的正确选择。     

Benefits of Conservation Agriculture on Soil and Water Conservation and Its Progress in China

Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture (CA) is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement,and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world's arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture.     

Fishermen's perception on the sustainability of small‐scale fisheries and dolphin–fisheries interactions in two increasingly fragile coastal ecosystems in western Greece

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