Metapopulation dynamics and conservation of the marsh fritillary butterfly: Population viability analysis and management options for a critically endangered species in Western Europe

This study investigates the dynamics and viability of a marsh fritillary butterfly Euphydryas aurinia metapopulation in a Belgian successional landscape. Based on capture-mark-recapture and winter nest census data, we first estimated demography (survival and recruitment rates, population size, density dependence) and dispersal parameters (emigration rate, effect of patch connectivity on dispersal, mortality during dispersal). Then using RAMAS/GIS platform, we parameterised a population viability analysis (PVA) model with these parameters to simulate the future of this metapopulation under different scenarios.The metapopulation does not seem viable even if natural reforestation is controlled by adequate management. In its present state, the patch system is not able to sustain enough individuals: due to the large temporal fluctuations in demographic parameters, a carrying capacity far higher than currently would be necessary to limit extinction risk to 1%, suggesting the existence of an extinction debt for the species in Belgium. The situation of E. aurinia appears much worse compared to two other fritillary species threatened in Belgium, for which similar PVA are available. It is therefore urgent to increase the carrying capacity of the patch system. How and where it is achieved are of secondary importance for the gain in viability: improvement of habitat quality through restoration, or increase of habitat quantity via enlargement of existing patches and/or creation of new habitat in the matrix. A regime of management based on regular re-opening and maintenance of habitat patches may be the only guarantee of long-term persistence for this critically endangered species in Belgium.     

MEASUREMENT OF THE MOBILITY OF SOIL COLLOIDS

A method is described for measuring the relative mobility (RM) of colloidal suspensions. It was used to assess the potential mobility of clay in the horizons of 12 profiles from Belgium, Bolivia, Brazil and India. The colloid from surface horizons of soil was always more mobile than that from deeper layers. The values of relative mobility differed between profiles and appeared to give a useful indication of potential clay migration under natural conditions.     

Influence of soil properties on the adsorption-desorption of sulcotrione and its hydrolysis metabolites on various soils

The retention process of sulcotrione and its two hydrolysis products, 1,3-cyclohexanedione (CHD) and 2-chloro-4-methylsulfonylbenzoic acid (CMBA), were studied in four different soils (Belgium, Landes, Perpignan, and Martinique) under laboratory conditions. Adsorption isotherms were well fitted by a Freundlich relationship. The values of K(fa) ranged from 0.4 to 27.0, and the most adsorbed compound was CHD regardless the soil type. Sulcotrione and CMBA exhibited similar retention behaviors. According to adsorption and desorption results, sulcotrione presents a moderate affinity with soil components; however, its leaching capacity needs to be carefully assessed. Clay content seemed to be the most important factor influencing the adsorption capacity of each compound, whereas organic matter and pH had little influence. The soils were classified according to their adsorption capacity in the following decreasing order: Martinique, Belgium, Landes, Perpignan.     

流域资源的多样性与流域管理目标确定

从流域资源多样性的角度和可持续发展理论,论述了流域管理目标的确定方法,提出了应按流域资源不同来确定最基本的４个流程管理目标,既保护型流域,恢复型流域,经济型流域和景观型流域。分析了流域管理目标的动态性以及与流域管理措施,管理效益评价之间的关系。     

Human ecology and coastal-zone pollution

A most critical problem today is an ecological one of relating human society harmoniously to its natural environment. The awareness of environmental problems has created a favorable climate for an intellectual orientation relevant to contemporary problems. Translating public opinion and legislation into long-range planning and rational policy for environmental resources is no simple task; an understanding of ecological principles, economic realities, and governmental jurisdictions and programs is needed. The present condition of our inshore seas, estuaries, and coastal-zones demonstrates how many immediately inadverse decisions prove damaging over the long run. The principles of general ecology, largely derived from studies of natural ecosystems in which the influences of man are minimal, can provide helpful insights into managing the complex natural and human ecosystems of the coastal land-water interface. The concepts of carrying capacity, limiting factors, productivity, and homeostasis lead to a more complete understanding of pollution. Pollution can be defined as a residual, a left over from production and consumption activities. Residuals management becomes a matter of social choice, a process by which the underpriced assimilative capacity of the environment is treated as an input into social accounting and is priced accordingly. The ability of governments to provide effective management for environmental quality will depend upon the implementation of rationally determined development plans based on an understanding of residuals management. The natural resource ecosystems of our coastal areas can provide man with increased benefits in the form of visual amenities, recreational benefits, and ecosystem homeostasis. Problems of management are critical and increasing. The opportunity exists to manage these important ecosystems with intelligence rather than by default.     

昆虫野花带在农业景观中的应用

在农业景观中,昆虫野花带是以混播等方式,建植在农田、果园、菜地等农地边缘的条状或片状生态缓冲区。通过配置不同功能植物形成植物群落,为自然天敌及传粉者提供蜜粉源和栖息地,改善农地生境质量;强化害虫天敌支持系统,达到提高授粉率、减少农药使用、改良修复农地土壤、净化水源、抑制杂草等多样的生态系统服务功能。本文回顾了昆虫野花带的应用发展历程,涵盖了中西欧发达国家及美国等地。不同国家昆虫野花带侧重不同,瑞士、比利时等国家作为昆虫野花带的源头,最早将生态保育的思想运用于农业生产,并付诸生态补偿机制的实践;英国昆虫野花带有政策的细化支持,应用方式丰富;美国以本土植物的开发、草原生境的修复及重要传粉者保护为研究与实践的重点。中国的农地周边由于外来物种入侵、人为干预严重等造成了景观异质性低、生境破碎化,亟待引入昆虫野花带的技术手段,进行生境管理与规划。中国的昆虫野花带研究仍处于发展初期,缺少实际应用。未来,中国昆虫野花带的发展,首先要针对现有非作物生境植物群落以及各类昆虫群落展开动态监测与调查,在大尺度上划定生态保护区域,分析现有生境格局,构建生态网络,研究昆虫野花带的规划方案,分清主次和功能需求,并根据节肢动物功能团的时空动态变化,确定最佳群落结构,保持昆虫野花带生境与其他自然与半自然生境的功能连接度,保留多样的景观因素。     

IMPACT OF INTEGRATED NUTRIENT MANAGEMENT ON TOMATO YIELD QUALITY AND SOIL ENVIRONMENT

Sustainable agricultural production incorporates the idea that natural resources should be used to generate increased output and incomes, especially for low income groups without depleting the natural resource base. Integrated nutrient management (INM) integrates the use of all natural and man- made sources of plant nutrients, so that productivity and nutrient status of food increases in an efficient and environmentally benefiting manner without sacrificing soil productivity of future generations. Integrated nutrient management relies on a number of factors including appropriate nutrient application and conservation and the transfer of knowledge about INM practices to farmers through extension personal. Tomato is the most popular home garden and the third most consumed crop in the world. It is very much beneficial for health because of its high nutrient status. Integrated nutrient management effects on its yield and quality parameters to a great extent. This review paper therefore, present review on various aspects of INM use to improve soil environment and tomato yield and quality parameters.     

Investigation into the possible natural occurence of semicarbazide in Macrobrachium rosenbergii prawns

In the past year there has been an increased incidence in Belgium of cases of positive semicarbazide (SEM) tests in imported freshwater Macrobrachium rosenbergii prawns, seemingly indicating the possible abuse of nitrofurazone, a banned antimicrobial agent. This was in contrast to all other European countries where no significant increase in SEM-positive samples was detected. A possible explanation for this discrepancy between Belgium and the other European Union member states could be the fact that only in Belgium were whole prawns (meat + shell) analyzed for the presence of tissue-bound metabolites of nitrofurans, whereas in the other countries only the edible part (meat) of these prawns was analyzed. To investigate the possible natural occurrence of SEM in freshwater prawns, an animal trial was set up. In this experiment two groups of 10 juvenile M. rosenbergii, previously raised under standardized laboratory conditions, were stocked into two separate aquaria, a control group under reference conditions (no addition of nitrofurazone) and a group exposed to a daily dose of 50 mg of nitrofurazone L(-1) of culture water. Results of this animal trial proved that SEM naturally occurs in M. rosenbergii prawns but that at the current minimum required performance limit (MRPL) no tissue-bound SEM can be found in the meat of nontreated animals. In addition to this animal trial, commercial samples of other crustacean species, the shell and meat of which were analyzed separately, were also analyzed for the presence of SEM.     

Temporal changes (1986-1999) in populations of primrose (Primula vulgaris Huds.) in an agricultural landscape and implications for conservation

In Belgium, Primula vulgaris is a rare and declining species. Its fate is bound up with the ever-changing agricultural landscape in northwestern Belgium and analysis of historical data showed a shrinking distribution area during the last decades. Contrary to the situation in England and France, most of the populations are situated in small landscape elements in the agricultural landscape and not in woodland. The population size distribution is skewed to very small populations (<10 individuals) with few younger life stages in small populations, higher proportions of older adults and unequal flower morph numbers. The changes in several population traits during a 13-year interval are correlated with initial population status, indicating that small populations tend to be more prone to extinction than larger ones. Small remnant woodland patches may be seen as ‘safe sites’: in this environment population sizes were more or less stable during the 13-year period whereas populations in ditches around arable fields were particularly susceptible to decline. Under current conditions, the long term survival of the species in small landscape elements is highly critical unless land use practices change drastically in the near future. The minimum viable populations concept and management of small landscape elements are discussed.     

四川盆地丘陵区农户行为对耕地质量的影响

农户行为是耕地质量变化的直接推动者,农户对不同质量耕地的响应直接影响耕地现实生产能力。该文采用BP神经网络模型对重庆市大足县耕地自然质量进行评价,发现研究区水田自然质量等级以二等地和三等地为主,旱地以一等地和二等地为主,耕地自然质量总体偏高;但耕地自然质量仅仅是耕地自然属性的反映,因此在基于对研究区农户行为调查的基础上,采用“影响力系数”对耕地自然质量进行修正,并将农户收益作为耕地质量货币化价值的表现,进一步讨论了耕地自然质量和农户投资结构对这种价值的影响以反映对耕地质量的影响。结果显示,耕地自然质量指数和农户收益间的数学关系以三项式模型、二项式模型等曲线方程模拟效果最佳,重庆市大足县大部分乡镇都是受到某单一投入因素的制约,通过分析弹性系数大小可以调整研究区农户投资结构。该文阐明耕地质量不仅仅取决于耕地自然属性,还受到农户行为诸如投入水平、管理方式、种植模式等因素的制约,因此,应进一步规范农户行为以提高耕地质量。     

Functional conservation units for the endangered Alcon Blue butterfly Maculinea alcon in Belgium (Lepidoptera: Lycaenidae)

To organize and prioritise species-specific conservation efforts, we delineate `functional conservation units' for the threatened Alcon Blue butterfly Maculinea alcon in Belgium. We used detailed distribution data on the butterfly, its host plant and its habitat, present-day population sizes and its mobility and colonization capacity to determine functional conservation units (FCUs) on different spatial scales: FCU-1, i.e., the 12 presently occupied habitat patches plus the area within a range of 500 m surrounding them (the maximum local movement distance, based on mark-release-recapture data), FCU-2, i.e., the areas within a range of 2 km around the occupied habitat patches (the maximum observed colonization capacity) and FCU-3, i.e., potential re-introduction sites (sites where M. alcon went extinct recently). We suggest different management and planning measures for each type of functional conservation unit and discuss translocation and re-introduction as `intensive care' conservation measures for this threatened and sedentary species.     

Plaggen Soils: landscape history,properties, and classification

Plaggen soils were produced by farmers in the sandy lowlands of Denmark, NW Germany, Belgium, and the Netherlands by long‐term application of plaggen manure. The present paper summarizes the genesis, the properties, and the landscape impact of plaggen soils. The objectives and methods of plaggen management are outlined. Evidence for the plaggen management can be traced back to the late Bronze Age. It has continued until the last century. Numerous references indicate the geographical expansion of plaggen management over Europe. The various conditions of plaggen soil formation are reflected by their basic physical and chemical properties. Recent investigations of soil organic matter composition in sandy plaggen horizons revealed large proportions of lipids and fatty acids and some similarity with organic matter in Podzol B horizons. Finally, the classification of plaggen soils is discussed. In the World Reference Base of Soil Resources (ISSS/ISRIC/FAO, 1998), most of them are classified as a separate subunit: within the reference soil group of Anthrosols, they differ from other artificially transformed soils, and are classified as Plaggic Anthrosols.     

重要农业文化遗产价值体系构建及评估(I):价值体系构建与评价方法研究

重要农业文化遗产是一类典型的资源可持续利用保护地,其水土管理方式、知识体系、文化内涵等对于协调社区生计与生态保护具有积极作用。这类传统生计区域往往与自然保护地毗邻或在其范围内,对其蕴含的价值进行识别与保护,不仅是提升农业文化遗产管理的诉求,也能够支持自然保护地体系优化与功能区划管理。本研究对重要农业文化遗产价值进行系统识别,基于农业文化遗产的广义概念与全球重要农业文化遗产的狭义概念,借鉴多类型自然保护地与世界遗产、生态系统服务功能、自然资源资产等价值体系,从农业文化遗产的复合性、活态性与战略性特点出发,把握其核心价值,构建重要农业文化遗产的价值体系。在充分吸收生态系统服务价值评估、自然资源资产价值核算、自然文化遗产价值评估、品牌价值评估等定量或定性评价方法的基础上,提出一套完整的重要农业文化遗产货币价值评价方法。以系统科学和可持续发展理论为基础,重要农业文化遗产价值主要包括存在价值和潜在价值,其中存在价值以载体价值和服务价值为核心,服务价值则可细分为产品价值、生态价值、社会价值等9类,25个具体指标。研究进一步提出存在价值的评价方法与潜在指标可能测算路径。构建的重要农业文化遗产价值体系以及所提出的评价方法,可为以价值保护为基础进行农业文化遗产管理提供理论依据,为管理决策者在区域保护与发展协调决策中提供科学基础。     

The role of soil microorganisms in environmental and food security

The review considers some problems of soil microbial system management, as well as the possibilities, constraints, and risks caused by environmental and food security problems. A natural microbial system, which obeys its own dynamic laws, is considered a required condition for the existence of a biosphere. Ignorance and disregard of these laws can lead to catastrophic consequences for the higher hierarchical system in which humanity acts.     

自然灾害的风险特征及风险管理模型的探讨

随着人口的增加和城市化的发展,自然灾害问题将更加严峻,理解自然灾害的风险特征比以往任何时期都显得更加重要.在认识自然灾害风险的特点和风险概念的基础上,本着科学与实用,通用与开放的原则,构建一个由风险鉴别、风险分析、风险评估和风险处理四个模块组成自然灾害风险管理模式,该模型具有灾害风险管理的基本思路和系统方法,能够为灾害风险管理提供行动指南.     

澳大利亚、中国和泰国的热带地区的土壤化学退化的量化及修复

Soil and land degradation in the tropics can be identified and described in terms of physical,chemical,and biological changes from its pristine state brought about by natural and anthropogenic influences.A characteristic of these ecosystems is their capacity to recycle nutrients through soil organic matter(SOM). Following disturbance through changed land management.SOM is rapidly mineralized and there is a cor responding decline in fertility and the variable charge component of the cation exchange capacity.As these ecosystems are strongly dependent on SOM for their functionality,changed land use can have irreversible impacts on the productivity of these systems.The paper focuses on quantifying chemical degradation throughbenchmaking using data from paried sites in tropical China and Thailand using surface charge finger printing.Using values taken from the fingerprint of an undistubed soil,an index of chemical degradation from ideality was calculated.Various management stratgeies that attempt to reverse degradative trends or improve poor quality soils in their natural condition are discussed.such as the ddition of natural clays and silicated materials.Results are present to whow the effect of each of the aforementional strategies on surface charge characteristics and associated increases in plant productivity.     

Evaluating an integrated approach to catchment management to reduce soil loss and sediment pollution through modelling

Abstract. Soil erosion and sediment delivery cause many environmental problems posing a substantial financial burden upon society. Policy makers therefore look for a strategy to minimize their impact. The spatial nature of soil erosion and sediment delivery, as well as the variety of possible soil conservation and sediment control measures, requires an integrated approach to catchment management. To evaluate such management, a spatially distributed soil erosion and sediment delivery model is necessary. Such a model (WaTEM/SEDEM) was applied to three agricultural catchments in Flanders (Belgium). The model was first used to identify where the measures to control soil loss should be taken. Secondly, a scenario analysis was used to select the most effective set of techniques. The findings showed that soil conservation measures taken in fields are not only effective in reducing on-site soil loss, but also in drastically reducing sediment yield. Off-site sediment control measures appear to be much less effective in reducing sediment yield than previously thought. The results also suggest that data from field experiments cannot be extrapolated to a catchment scale.     

Trends in organic carbon and nitrogen contents in agricultural soils in Bavaria (south Germany) between 1986 and 2007

In the last 60 years traditional agriculture in industrialized European countries, which had initially been dependent on available natural resources, has shifted towards a massive intensification of nutrient turnover because of cheap energy and low‐cost synthetic fertilizers. At the same time farm structure has undergone profound changes, resulting in an increase in the number of specialized farms to the detriment of traditional non‐specialized ones. All these trends have had a significant impact on agricultural management. The intensification of agricultural management together with climate change could affect the quantity and quality of soil organic matter (SOM). That could imply decreasing soil fertility, reduced harvest yields, increasing nutrient losses and additional greenhouse gas emission. In order to measure the long‐term development of SOM in agricultural soils a monitoring programme was initiated in Bavaria in 1986. The measurements are based on 92 representative plots located on cropland and 21 plots located on managed permanent grassland. Between 1986 and 2007 the monitoring plots have been sampled four times. The monitoring results suggest a decrease of soil organic carbon content, total nitrogen content and C:N ratio in cropland as well as in grassland in Bavaria between 1986 and 2007. Crops and organic fertilizers are together with the initial SOM content the main causes of the observed changes in SOM quantity and quality. A climatic effect could be neither proved nor excluded. The results in Bavaria are consistent with the reported changes in organic carbon of agricultural soils in Austria, Belgium, France, the Netherlands and England. In Bavaria we should expect declining SOM stocks, particularly soil organic carbon, in agricultural soils if the supply of organic matter remains constant or even decreases.     

子午岭人工油松林不同管理方式对土壤腐殖质性质及结合形态的影响

以黄土丘陵沟壑区的子午岭人工油松林区的土壤为研究对象,综合研究了不同管理措施,不同深度土壤的腐殖质组成、结合形态及胡敏酸的光学特征。结果表明:不同管理方式下土壤腐殖质各组分有机碳含量为胡敏素(HM)富里酸(FA)胡敏酸(HA),其对土壤腐殖质组分和结合形态的影响主要集中在0-40cm土层之间;PQ值天然油松林(N)粗放管理型(E)精细管理型(F),油松林各层土壤的PQ均小于26%;E4/E6和色调系数(ΔlogK)的值为FEN,RF的平均值为NEF。综合研究表明,天然油松林土壤有机碳的腐殖化程度和芳化度较人工油松林显著提高,说明人为干扰不利于土壤腐殖质品质的提高,反而使其腐殖化程度下降,降低土壤胡敏酸的氧化稳定性,不利于森林土壤的肥力发展。     

Principles of managing man-made soils

Abstract. Assuming that there is no major chemical toxicity or deficiency, the major limitation in man-made soil is the loss of its natural structure, which, in turn, controls the air-water balance. Where such a soil has < 70% sand content this loss may adversely affect potential for use.
Examples of man-made soils - sports turf and replaced opencast coal mining land - are used to illustrate principles of management. Two strategies exist: to encourage earthworms, thereby promoting effective site drainage by infiltration or, to limit their activity and rely mainly on surface shed. The implications of each of these soil options for wider management and use are discussed.