Potential and attainable food production and food security in different regions

Growing prosperity in the South is accompanied by human diets that will claim more natural resources per capita. This reality, combined with growing populations, may raise the global demand for food crops two- to four-fold within two generations. Considering the large volume of natural resources and potential crop yields, it seems that this demand can be met smoothly. However, this is a fallacy for the following reasons. (i) Geographic regions differ widely in their potential food security: policy choices for agricultural use of natural resources are limited in Asia. For example, to ensure national self-sufficiency and food security, most of the suitable land (China) and nearly all of the surface water (India) are needed. Degradation restricts options further. (ii) The attainable level of agricultural production depends also on socio-economic conditions. Extensive poverty keeps the attainable food production too low to achieve food security, even when the yield gap is wide, as in Africa. (iii) Bio-energy, non-food crops and nature compete with food crops for natural resources. Global and regional food security are attainable, but only with major efforts. Strategies to achieve alternative aims will be discussed. <br>     

动物内温性进化研究进展

对动物内温性进化的研究进行了较为系统的论述,包括内温性动物概念的由来、特点和起源的选择因子。内温性起源的选择因子包括8个模型：热生态位扩展模型、恒温与代谢效率模型、降低个体大小模型、姿势改变模型、增加脑大小模型、有氧呼吸能力模型、双亲行为模型和同化能力模型。其中后3个模型较为重要。有氧呼吸能力模型认为,选择提高支持物理运动的最大呼吸能力,而增加的静止代谢作为其相关反应而得以进化。该假说得到种内研究数据的支持,而种问的数据并小完全支持。双亲行为模型是指在鸟兽类中,内温性是对双亲行为选择的结果,因为内温性为双亲控制抚育温度提供了保证。同化能力模型认为,在鸟类和兽类中内温性进化由以下两个因素所推动：①子代出生后双亲行为加强;②为支持每日总体能量高速消耗所需,动物内脏器官能力增强而导致的较高维持消耗。     

自然资源资产负债表编制与资源环境承载力评价

探索编制自然资源资产负债表和建立资源环境承载力监测预警机制是十八届三中全会做出的重大决定。当前,自然资源资产负债表正处在探索试编阶段,资源环境承载力评价正在由分类评价走向综合计量的关键节点。"自然资源资产负债表编制与资源环境承载力评价技术集成与应用"项目(2016YFC0503500)面向国家资源环境统计核算的业务化需求,旨在发展自然资源资产负债表编制与资源环境承载力评价的方法与技术体系,提出自然资源资产负债表编制和资源环境承载力评价的技术标准/规范,研发自然资源资产负债表编制与资源环境承载力评价的数字化业务平台,实际应用于国家示范区并形成相应的配套政策及建议,为政府部门提供科技支撑和政策建议。     

九寨沟世界遗产地旅游可持续发展实践和讨论

近30年来,九寨沟在推进旅游可持续发展方面进行了长期有益的探索和实践,其经验获得国内外的普遍认同。与此同时,日益增长的游客规模对生态环境和生物多样性保护的威胁,逐渐成为旅游可持续发展面临的最大挑战。生物多样性保护是九寨沟的使命之一,在游客容量测算中应予以充分考虑,这在游客规模日益增加的背景下尤显重要。但是目前传统的游客容量测算中却没有涉及生物多样性容量,而且由于生物多样性监测数据和相关知识不充分,生物多样性容量也难以进行测算。因此,需要在下一步有针对性地积累生物多样性监测数据,将其结果纳入游客容量测算中,并在此基础上探索执行以监测为基础的游客容量适应性管理机制。     

Silvopasture for reducing phosphorus loss from subtropical sandy soils

Phosphorus (P) losses from sandy soils that are predominant in the 1.4 million ha of pastureland in Florida are a major cause of water pollution. We hypothesized that soil P loss would be lower from silvopastoral systems than from treeless pastures because soil P removal by a combined stand of trees and pasture would be more than that of treeless pasture. Four slash pine (Pinus elliottii Engelm.) + bahiagrass (Paspalum notatum Flüggé) silvopastoral systems located in Alachua, Suwannee, Manatee, and Osceola counties in Florida were selected for the study. The former two sites are on Ultisols, and the latter two on Spodosols. Soil samples were collected at different depth increments. Soil P storage capacity (SPSC), the maximum amount of P that can be safely applied to a soil before it becomes an environmental concern, was calculated. Water-soluble P concentrations in the 0–5 cm soil layer ranged from 4 to 11 mg kg⁻¹ for the silvopasture sites and 10 to 23 mg kg⁻¹ in the treeless pasture sites, with higher P concentrations in the treeless pasture at each location. Total SPSC in the upper 1 m depth ranged from 342 to 657 kg ha⁻¹ in the silvopasture sites and −60 to 926 kg ha⁻¹ in the treeless pasture sites (a negative value indicates that the soil is a P source). The results suggest that P buildup within the soil profile and therefore the chances for loss of P from soil to water bodies were less from silvopastures than from treeless pastures. Thus, silvopasture systems can be expected to provide greater environmental service in regard to water quality protection compared to treeless pastures under comparable ecological settings Responsible Editor: Peter Christie.     

几种Protein A亲和层析填料纯化重组单克隆抗体效果的比较

随着表达技术的进步以及发酵技术的优化,细胞发酵上清液中抗体的滴度大幅度提高,必然对下游纯化工艺的处理能力有更高的要求。Protein A亲和层析是分离单克隆抗体的一种标准纯化方法。目前已经有很多种protein A亲和填料,其配体基本上都是大肠杆菌发酵的重组protein A。不同厂家生产的protein A填料有各自不同的基质或键合技术,从而造成填料对抗体亲和力以及对碱耐受性的差异。针对正在研发的WLB303单克隆抗体,比较了6种不同的protein A填料的动态载量,并从洗脱溶液种类和p H两个方面进行单克隆抗体纯化条件的筛选,分析纯化后样品SEC纯度和回收率。综合考虑载量、除杂效果、回收率三个因素,Mab Select填料是最适合本抗体纯化的,SEC纯度可以达到98%,回收率可以达到100%左右。基于这些数据,对Mab Select填料进行了使用寿命试验,200次循环之后载量仅衰减了5%。     

Challenges for biodiversity monitoring using citizen science in transitioning social–ecological systems

Biodiversity monitoring requires sound data collection over large temporal and spatial scales in order to inform policy and conservation management. Citizen science programmes, if designed appropriately, can make valuable contributions to data collection and analyses. Moreover, citizen science has potential for both environmental education and civic participation. Recommendations on effective citizen science are available in the literature, but most existing work has come from relatively rich, industrialized countries. By contrast, there is very little knowledge on citizen science projects in transitioning economic, social and cultural settings. This paper seeks to adjust this deficit by contributing insights from our attempt to initiate a new monitoring scheme in Romania. We draw on our experience of conducting workshops, training events and camps to strengthen citizen engagement in a butterfly monitoring scheme, and discussions with many stakeholders engaged in other monitoring programmes inside and outside of Europe. We highlight four general themes that are worth considering when initiating new citizen science projects in socio-economically challenging settings: (i) engaging citizens requires a combination of formal and informal support; (ii) a culture of volunteering requires education as well as building capacity and confidence; (iii) citizen science needs active integration of both national experts and local stakeholders; and (iv) successful monitoring schemes require effective leadership. We conclude that particular attention should be paid to the cultural legacies of the target area.     

Thiols are main determinants of total antioxidant capacity of cellular homogenates

While the total antioxidant capacity (TAC) of blood plasma is mainly accounted for by urate, TAC of cell interior can be expected to depend more on other antioxidants, especially glutathione and protein -SH groups. We studied TAC of homogenates of several lines of cultured cells subjected to the action of thiol-modifying agents. Comparison of changes of TAC of the homogenates and of the level of total thiols (determined with a biradical spin label) demonstrates that alterations in cellular thiol content is the main determinant of changes of TAC of cell homogenates. These results show that estimation of TAC of cell extracts may be a useful parameter of assessment of oxidative stress, primarily of oxidation of thiol groups, yielding information different than TAC of body fluids.     

Implications of land cover change on ecosystems services and people’s dependency: A case study from the Koshi Tappu Wildlife Reserve,Nepal

Protected areas, a corestone of biodiversity conservation, provide a vast array of ecosystem services to support livelihoods of people. However, protected areas, especially freshwater, are under threat with overexploitation of resources changing the land covers and degrading their capacity to supply services. Information on land cover changes and its implications on ecosystems, its services and people, especially in developing countries at a local scale, is largely absent. This study, therefore, seeks to understand people's dependency on ecosystem services and implications of land cover change on ecosystem services and people, with a case study in the Koshi Tappu Wildlife Reserve of Nepal. Using both qualitative and quantitative methods, our findings show high dependency of the locals on a vast array of ecosystem services provided by the reserve. More than half of the sampled households were found to directly derive income from ecosystem services of the reserve. However, land cover changes especially declines in forest (16%), swamps/marshes (4%), rivers (14%) and other ecosystems over a period of 34-years impacted the provision of ecosystem services and people’s dependency notably. The services from forests declined by about 94%, swamps services by 36% and services from river by 57% which were reported to be the high service suppliers. People's dependency, as perceived by the locals, was reduced by 67% over the last ten years. The study highlighting the supply, demand and implications on ecosystem services and people helped to better understand the complex interaction between humans and ecosystems. These results can be used to develop holistic approaches to restore, conserve and manage the ecosystems, and its services by balancing equal supply and demand of ecosystem services required for a self-sustaining human-environment system. It can also contribute to development of important environmental policies and programs in the area.     

保护中国的植物遗产(英文)

China’s rich floral diversity includes more than 33 000 vascular plant species,representing approximately 10 percent of all known plant species.Over half of these species are endemic to China.However,China’s rapid economic development in the last 30 years and continuous population growth have seriously damaged plant resources in the wild and the ecological environment,resulting in a dramatic increase in the number of endangered species.There are nearly 4 000 to 5 000 higher plants that are now threatened or on the verge of extinction.To help halt the loss of Chinese plant diversity,Botanic Gardens Conservation International(BGCI) has developed a China programme and opened its first office based in Guangzhou in 2008.This office works along with Chinese partners aiming to secure Chinese plant diversity through integrated conservation approaches with reintroduction/population reinforcement,engagement of local communities in conservation activities,capacity building in horticulture and environmental education and public outreach.