Epigeic Collembola in winter wheat under organic,integrated and conventional farm management regimes

Community characteristics of Collembola assemblages in conventional, integrated and organic fields of winter wheat were compared among three randomly chosen areas in England using analysis of similarities, cluster analysis, multi-dimensional scaling and several measures of diversity and evenness. Indicator values were used to identify indicator species. Significant differences were found in the abundance of most species and in community structure among the three geographical regions but few differences between the farming regimes were significant. Despite a lack of significant differences among regimes, Entomobrya multifasciata and Isotomurus spp. were consistently, although not significantly more common in conventional than organic fields whereas the opposite was true for Isotoma viridis and Isotoma notabilis. Farming regime significantly affected the abundance of Sminthurinus elegans and Sminthurus viridis but the effect differed between geographical regions. Community composition and species dominance were influenced by farming regime, but no species were indicative of the different farming systems, as most occurred ubiquitously in all fields. Organically and conventionally farmed fields were found not to differ significantly from each other in community composition, but both differed from integrated fields. These findings are compared with the results from other recent European studies of the effects of farming systems on arthropods and their wider ecological implications are discussed.     

Grassy field margins and arthropod diversity: a case study on ground beetles and spiders in eastern Austria (Coleoptera: Carabidae; Arachnida: Aranei, Opiliones)

In 1983, the species composition and diversity of carabids, spiders and harvestmen was investigated by pitfall traps in a grassy field margin and in an adjacent, biologically farmed wheat field at Obere Lobau, Vienna, Austria.The carabid fauna of both habitats was diverse; it showed a high degree of similarity, the abundant species in both habitats being represented by typical field species. Only Metophonus spp. predominantly lived in the margin. Numerous species of different habitat origin occurred in the margin at low abundances indicating transitional stay rather than permanent populations.In contrast, the spider fauna showed a low degree of similarity, with few agrobiotic species strongly dominating field fauna. In the field margin, a rich spider fauna containing rare elements indicates the general importance of grassy margins for nature conservation. The apparently low faunal exchange of spiders between the two habitat types is discussed. Harvestmen occurred mainly in the field margin; only two thermophilic species invaded the field.Seasonal fluctuations in the trapping numbers of Bembidion lampros, Platynus dorsalis and Brachinus explodens are interpreted as indicating migrations between field margin and field. Poecilus cupreus and certain other field species, however, apparently spend their entire life cycle in the field. The possible function of field margins for restoration of carabid losses due to impacts of intensive cultivation is discussed.It is concluded that both grassy field margins and sustainable farming methods, in particular biological farming, are necessary to maintain a diverse predatory arthropod fauna in agroecosystems.     

Yield loss in conventional and natural rice farming systems

Compared to modern, conventional agriculture, alternative agricultural production systems may rely on biologically different mechanisms (syndromes) to attain similar production goals. Yield loss to rice in conventional and natural farming rice paddies in Japan was evaluated by simulated injury (leaf-clipping) and monitoring plants damaged by insect herbivores. Rice grown under natural farming practices was more tolerant of simulated injury and injury from Oulema oryzae than rice grown under conventional practices. Natural farming rice retained proportionately more tillers and had a higher proportion of mature seeds than conventionally grown rice. In conventional paddies, the simulated injury may have made the rice plants more susceptible to plant pathogens than their non-injured counterparts, resulting in higher disease attack and proportionately greater yield loss. These results suggest that, pests may affect yield loss independently in natural farming, but in conventional paddies, multiple pest injury may interact synergistically, compounding yield loss.     

Econometric analysis of the determinants of adoption of alley farming by farmers in the forest zone of southwest Cameroon

Slash-and-burn agriculture continues to expand in many parts of the forest zone of Cameroon. One alternative land use to slash-and-burn system is alley farming. This paper quantifies, using an econometric model, the factors determining farmers’ adoption and use of alley farming variants in southwest of Cameroon, based on a survey of 156 farmers in 11 villages in the region.The analysis showed that male farmers are more likely to adopt than women. Adoption is higher for farmers with contacts with extension agencies working on agroforestry technologies. Adoption is higher for farmers belonging to farmers’ groups. Adoption is lower for farmers in areas with very high population pressure, as farmers in such areas may have greater labor productivity from use of less labor intensive natural resource management technologies like chemical fertilizers. Adoption is higher for farmers in areas facing fuel wood scarcity. Farmers have made adaptations to the conventional alley farming technology recommended by researchers, the most significant adaptation being the introduction of fallow periods into the system. Farmers use alley farming as a land use option, not as a replacement for the slash-and-burn system, since land supply is still relatively elastic. Achieving increased impact with alley farming variants requires effective targeting. Results showed that econometric modeling using farmer and village characteristics, socioeconomic and institutional variables can lead to more effective targeting to farmers and locations where higher adoption rates may occur.     

土壤重金属污染风险筛选值划分方法:以Cd为例

《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB 15618-2018)给出了我国土壤环境质量的风险筛选值,但由于不同地区土壤组分及理化性质等方面的差异,使得该值对某些地区存在局限性.基于《食品安全国家标准食品中污染物限量》(GB 2762-2017)中给出的农作物中污染物的限值,以渝东南主要农耕区土壤中Cd为例、元素生物有效态的含量为基础划分建议筛选值.此方法可为重金属生物有效性较高、较低或Se元素含量丰富等典型地区完善土壤重金属及健康元素阈值提供借鉴和参考.     

Influence of conservation tillage on winter bird use of arable fields in Hungary

Bird use of conservation tillage-established (CT—seedbed preparation without soil inversion) crops was assessed at two adjacent sites in western Hungary, in comparison with conventionally established (mouldboard ploughed—P) fields. Bird abundance was assessed in a typical rotation of spring-sown maize and winter wheat in three consecutive winters. In the first winter, several species and the guild of seed-eating passerines were significantly more abundant on CT established plots, in both crop types. In the second winter, only starlings were more abundant on CT plots. In the third winter, only skylarks favoured CT over P plots. In combination with agri-environment scheme measures designed to provide resources for biodiversity, conservation tillage could play a role in softening the impact of agriculture on farmland birds in Hungary and elsewhere in Eastern Europe, in addition to its potential for reducing soil erosion and diffuse pollution.     

Increasing land pressure in East Africa: The changing role of cassava and consequences for sustainability of farming systems

Increasing land pressure during the past three to four decades has transformed farming systems in the mid-altitude zone of East Africa. Traditional millet-, cotton-, sugarcane- and/or banana-based farming systems with an important fallow and/or grazing component have evolved into continuously cultivated cassava or cassava/maize-based systems. Within three to four decades, cassava cultivation increased from 1–11 to 16–55% of cropped fields in our six study sites. Declining soil fertility, and not labour or food shortage, was apparently the primary trigger for this transformation. The land use changes have increased nutrient offtakes and reduced nutrient recycling rates. Cassava and maize now account for 50–90% of nutrient removal. Whereas single-season fallows were the most important source of nutrient recycling on cropped fields in the past, currently cassava litterfall and maize stover contribute roughly 70% of nutrient recycling, with 50–70% of N, P and K recycled in cassava litterfall. This may explain why many farmers reason that cassava ‘rests’ the soil. With increasing land use pressure farmers progressively use cassava as an ‘imitation fallow’ throughout their farm. Farmers increasingly target cassava to poor fertility fields characterized by low pH and available P. High cassava intensities are nonetheless maintained on more fertile fields, probably to guarantee regeneration of soil fertility on all fields. Once cassava is targeted to poor fertility soils, farmers have run out of low-input management options and need to intensify management to maintain system productivity. As cassava is now used by more farmers and on a larger acreage than fallowing in the studied farming systems, cassava cropping could perhaps serve as an excellent entry point to strengthen system sustainability.     

The Energy and Environmental Benefits of Superconducting Power Products

Superconductivity has the potential to bring a more fundamental change to electric power technologies than has occurred since electricity use became widespread nearly a century ago. The potential is for an energy revolution as profound as the impact fiber optics has had on communications. The fiber optic ‘information superhighway’ was constructed by replacing copper wires with a higher capacity alternative. Superconductivity provides an ‘energy superhighway’ that greatly improves efficiency and capacity. The economic and energy impacts of superconductors are predicted to be huge. Many challenges are being addressed in order for superconductivity to play this important role in the electric power system. The difficult challenge is underway in many countries to manufacture electrical wire from the ceramic high-temperature superconducting (HTS) materials, while in parallel, super-efficient power devices that use these wires are being designed and demonstrated in field trials. The benefits can be substantial: HTS wires that are a resistance-free alternative to conventional wires while carrying 100 times the amount of electricity; oil-free electrical equipment that is environmentally benign, with half the energy losses and half the size of conventional alternatives; and addressable markets estimated to exceed US$10 billion per annum within the next two decades. The savings due to increased efficiency of HTS electric power products may exceed 36 million metric tons of CO₂ in Japan, and much higher numbers in the U.S. and Europe, if generation continues to rely upon fossil fuels.     

Phosphorus and cation dynamics of components and processes in conventional and no-tillage soybean agroecosystems

Phosphorus (P) and cation (K, Ca and Mg) dynamics in conventionally (moldboard) plowed and no-tillage soybean agricultural systems are compared on the Georgia Piedmont. Data are presented on crop and weed biomass and elemental content in these components over a 2-year period as well as seasonal dynamics of elemental concentrations in litter, soil, throughfall and soil water. Final accumulation of above-ground soybean biomass was greater in conventionally plowed treatments. Grain yields were significantly greater in the no-tillage treatments during 1 year of the study. Soybean root biomass was greater under conventional tillage management. Weed biomass was consistently higher with the no-tillage practice. In both tillage treatments, weed tissue had higher elemental concentrations than did soybean tissue. With P, Ca and Mg, there was a trend toward higher concentrations of these elements in no-tillage than conventional tillage litter. In the upper soil stratum (0–10 cm), K, more than the other three elements, varied the most markedly with tillage treatment. In the lower soil stratum (30–40 cm), P concentrations were consistently higher in the conventionally tilled soil. Concentrations of elements in soil water collected with porous-cup lysimeters indicated higher amounts of Ca, K and Mg in samples from the conventionally tilled systems, indicating that the no-tillage system was more conservative of these nutrients than the plowed system.     

Faunal loss from bushmeat hunting: empirical evidence and policy implications in Bioko Island

Bushmeat market data can be used to detect hunting sustainability by using proxies such as decline in sale volume and price increases over time. Here, we explore these proxies for the Malabo market in Bioko Island, Equatorial Guinea, the main bushmeat sale centre for the island. We gathered data during two sample phases (we call these ‘early’ and ‘later’) between March 1996 and October 1998, to test for evidence of faunal depletion during that period. Mammals (ungulates, rodents and primates) made up most of the bushmeat sold. Our analyses confirmed significant and sudden, rather than continuous, declines between phases, in total and individual animal group carcass volumes. Market species composition differed between phases; diversity indices and evenness increased in the later phase of the study. Price was related to species body mass and carcass condition (whether the carcass was smoked or fresh). Most species prices were higher in the later phase of the study. A total of 33 sites contributed bushmeat to the market, with over half of the recorded volume emerging from five sites in the south of the island. Bushmeat volume supplied from different regions of the island varied significantly between phases, and fewer sites contributed animals to the market during the later phase of the study. Proportionately more primates, ungulates but fewer rodents, appeared in the southern samples, compared with the northern. We suggest that in just over 2 years, hunting incursions, especially into the south of the island, may have resulted in drastic faunal losses. Subsequent data, collected by other authors, also indicate that the hunting spurt in the mid- and late-1990s may have irreversibly imperilled the island's mammalian fauna, since numbers of these animals entering the market have not increased since our study period. Although the Equato-Guinean authorities have recently initiated mechanisms to better protect the country's wildlife, through various legal and funding instruments, we suggest that these initiatives are likely to fail, if the social and environmental linkages are not fully understood to guide immediate restoration of such a unique African faunal assemblage.     

平衡施肥与秸秆覆盖对紫色土坡耕地养分及其化学计量的影响

为探究长期平衡施肥和秸秆覆盖对紫色土坡耕地土壤养分及其化学计量比的影响,以垫江县长期农田氮磷流失监测点为研究样地,设置3个处理：常规模式（CK）、平衡施肥模式（M1）和平衡施肥+秸秆覆盖模式（M2）,每个处理各设3个重复,共建立9个小区（长7 m×宽3 m）,并于2018、2019和2020年采集土样,研究不同处理下碳（C）、氮（N）、磷（P）和钾（K）含量及其化学计量变化特征.结果表明,2018年不同处理之间K含量差异显著,大小顺序为：CK>M2>M1;2019年不同处理之间硝态氮（NO₃^--N）、铵态氮（NH₄⁺-N）含量差异显著,表现为：M1>M2>CK;其他养分含量在同一年份不同处理之间差异均不显著.不同年份间各处理的土壤C和N含量差异不显著.2018年各处理中K含量均显著高于其他年份,其中,2018年的CK、M1和M2分别比2019年和2020年高78.26%和98.79%,19.13%和35.4%,54.49%和41.76%.P含量在CK和M2处理中均随着年份增大而减小,且2018年分别比2019年高20.29%和10.67%,比2020年高39.68%和17.33%.各处理不同年份间速效钾（AK）含量无显著差异,而NO₃^--N和NH₄⁺-N和速效磷（AP）含量差异显著,且均在2020年最高.土壤C ：P、C ：K、N ：P、N ：K和P ：K在不同年份间都表现出显著差异（P<0.05）.土壤C ：K、N ：K和AN ：AP分别于2018年和2019年在不同施肥模式间差异显著（P<0.05）.土壤C与N及P与K之间呈显著的线性正相关;土壤C ：K与C ：P、N ：K、N ：P和P ：K之间,N ：K与C ：P、P ：K和N ：P之间,N ：P与C ：P之间都呈显著的线性正相关;土壤P与C ：K和N ：K之间呈显著的线性负相关.土壤NO₃^--N与NH₄⁺-N、AN ：AP和AN ：AK之间,NH₄⁺-N与AN ：AP和AN ：AK之间,AP与AK和AP ：AK之间,AN ：AP与AN ：AK之间都呈极显著正相关.研究发现平衡施肥+秸秆覆盖是紫色土坡耕地较为适宜的管理模式.     

Runoff and sediment losses from 27 upland catchments in Southeast Asia: Impact of rapid land use changes and conservation practices

Rapid changes in upland farming systems in Southeast Asia generated predominantly by increased population pressure and ‘market forces’ have resulted in widespread land degradation that has been well documented at the plot scale. Yet, the links between agricultural activities in the uplands and downstream off-site effects remain largely unknown because of the difficulties in transferring results from plots to a larger scale. Many authors have thus pointed out the need for long-term catchment studies. The objective of this paper is to summarize the results obtained by the Management of Soil Erosion Consortium (MSEC) over the last 5 years from 27 catchments in five countries (Indonesia, Laos, Philippines, Thailand, and Vietnam). The purpose of the study was to assess the impacts of cultivation practices on annual runoff and erosion rates. Initial surveys in each catchment included topography, soils and land use. Monitoring included climatic, hydrologic and erosion (total sediment yield including bed load and suspended sediment load) data, land use and crop yields, and farmers’ income. In addition, new land management options were introduced through consultations with farmers and evaluated in terms of runoff and erosion. These included tree plantations, fruit trees, improved fallow with legumes, maize intercropped with legumes, planted fodder, native grass strips and agro-ecological practices (direct sowing and mulch-based conservation agriculture). Regressions analyses showed that runoff during the rainy season, and normalized runoff flow coefficient based on erosive rainfall during the rainy season (rainfall with intensity exceeding 25 mm h⁻¹) increase with the percentage of the catchment covered by maize. Both variables decrease with increasing soil depth, standard deviation of catchment slope (that reflects terrain roughness), and the percentages of the catchment covered by fallow (regular and improved), tree plantations and planted fodder. The best predictors of sediment yield were the surface percentages of maize, Job's tears, cassava and footpaths. The main conclusions generated from this study were: (i) soil erosion is predominantly influenced by land use rather than environmental characteristics not only at the plot scale but also at the catchment scale; (ii) slash-and-burn shifting cultivation with sufficiently long rotations (1 year of cultivation, 8 years of fallow) is too often unjustly blamed for degradation; (iii) in its place, continuous cropping of maize and cassava promotes high rates of soil erosion at the catchment scale; (iv) conservation technologies are efficient in reducing runoff and total sediment yield at the catchment scale; (v) the adoption of improved soil management technologies by upland farmers is not a function of the degree of intensification of their farming system and/or of their incomes. The results suggest that if expansion of maize and cassava into already degraded upland systems were to occur due to increased demand for biofuels, there is a risk of higher runoff and sediment generation. A failure to adopt appropriate land use management strategies will result in further rapid resource degradation with negative impacts to downstream communities.     

Vegetation changes in Conservation Reserve Program lands in interior Alaska

Over 14 million hectares of erosion prone cropland in the United States has been converted into grasslands through the Conservation Reserve Program (CRP) administered by the United States Department of Agriculture, however, studies of the effects of CRP enrollment on plant communities and subsequent plant succession are largely lacking. In Delta Junction, Alaska plant communities in CRP fields are transitioning from grasslands to shrub dominated plant communities, which are resulting in compliance problems with program regulations that state “fields must be maintained in a condition that permits easy conversion to cropland”. To determine plant succession and how previous land management and soils might influence the transition, we measured plant populations in 20 CRP fields throughout Delta Junction using modified-Whittaker plots. These data were combined with data on current management practices, previous farming history, soils, soil properties, diversity indices, and time since land was cleared and analyzed with nonmetric multidimensional scaling ordination to determine factors that influence plant succession. Time in the CRP was the only factor consistently influencing plant succession. As time in the CRP increased, the planted introduced grasses brome grass (Bromus inermis) and red fescue (Festuca rubra) and the native pteridophyte (Equisetum arvense) decreased, whereas a native grass (Calamigrostis canadensis), five native forb, two native shrub, and three native tree species increased. Plant diversity increased at a rate of more than 2 species per 1000 m² per year. Regression analyses of plant species and plant groups using time in the CRP as the dependent variable resulted in the identification of outlier CRP fields with significantly more or less than expected covers of vegetation. All fields with these outliers had reasonable explanations for the differences in cover that were unrelated to the overall rate of plant succession. Current management practices will result in incompliant fields and different management practices that result in woody vegetation control is key to maintaining CRP fields in compliance.     

Relationships between Danish organic farming and landscape composition

This article presents an investigation of relationships between organic farming and landscape composition in Denmark. Landscape composition was analysed in terms of density of uncultivated landscape elements (I), number of land uses per hectare (II), diversity of land use (III) and mean field size (IV). Two analytical approaches were used. The first was based on an examination of the national agricultural registers for 1998, 2001 and 2004. The second approach used aerial photo interpretation for an analysis of 72 conventional and 40 organic farms within three sample areas for 1982, 1995 and 2002. The national analysis indicated that organic farming has a direct effect on landscape composition. In 2001, organic farms were characterised by a higher number of land uses per ha, a higher land use diversity and smaller mean field sizes. From 1998 to 2004, conversion to organic farming was related to an increasing number of land uses per ha, increasing land-use diversity and decreasing mean field sizes. Relationships between organic farming and landscape composition were independent of variations in regional location, farm size or farm size change. At the level of sample areas, a significant relationship between organic farming and landscape composition was only found for densities of small biotopes. However, when differences in farm size and physical geographical conditions between conventional and organic farms were taken into account, several significant differences in landscape composition were clarified in two of the three sample areas. Furthermore, changes in landscape composition following conversion to organic farming were largely biased by the characteristics of the sample areas. Thus, in contrast to the national level, the sample area study indicated that differences in landscape composition between organic and conventional farms were not a direct implication of organic farming practices, but were related to variations within other parameters and to the location of organically farmed land.     

Influence of no-tillage on the distribution and lability of phosphorus in Finnish clay soils

No-tillage (NT) is a method adopted to reduce erosion and particulate phosphorus (P) load from arable land to watercourses. However, it has been found to increase the loss of dissolved P with surface runoff, but the reasons for that have rarely been examined in detail. The objective of the present study was to determine the chemical factors explaining this response by investigating the impact of NT on the type and distribution of P reserves as well as on organic carbon (C) in the 0–35 cm topsoil layer of clay soil profiles (Vertic Cambisols). Soil samples were taken from two experimental fields (Jokioinen and Aurajoki) at 0–5, 5–20 and 20–35 cm depths in conventionally tilled (CT) and non-tilled (for 4–5 years) plots. The plots had been cultivated and fertilized according to the common field practices in Finland (15–18 kg P and 100–128 kg N ha⁻¹ year⁻¹).Inorganic and organic P reserves characterized by a modified Chang and Jackson fractionation procedure were not significantly affected by the cultivation methods. However, in the uppermost soil layer (0–5 cm) in NT of the Jokioinen field, the labile P determined by water extraction (P_w) increased significantly, whereas the increase in P extracted with acid ammonium acetate (P_AAC) remained statistically insignificant. The increase in labile P coincided with a significant increase in organic carbon (C), which supports the theory that competition between organic anions and phosphate for the same sorption sites on oxide surfaces will enhance the lability of soil P. In the Aurajoki field with distinct soil cracking, P_w and P_AAC were not affected by NT in the uppermost soil layer, but they increased in the deepest soil layer (20–35 cm) concomitantly with an increase in Al-bound P and organic C. However, the increases were not statistically significant. In both fields, soil acidification due to the repeated application of N fertilizers at a shallow soil depth as well as the accumulation of organic C lowered pH of the uppermost soil layer in NT compared to the deeper soil layers. The results indicated that even short-term NT can increase the labile P in clay soil. However, further studies are needed to assess the long-term changes in lability of surface soil P and, consequently, the possible need for readjustment of the fertilization level in NT.     

Soil organic matter and biological soil quality indicators after 21 years of organic and conventional farming

Organic farming systems often comprise crops and livestock, recycle farmyard manure for fertilization, and preventive or biocontrol measures are used for plant protection. We determined indicators for soil quality changes in the DOK long-term comparison trial that was initiated in 1978. This replicated field trial comprises organic and integrated (conventional) farming systems that are typical for Swiss agriculture. Livestock based bio-organic (BIOORG), bio-dynamic (BIODYN) and integrated farming systems (CONFYM) were compared at reduced and normal fertilization intensity (0.7 and 1.4 livestock units, LU) in a 7 year crop rotation. A stockless integrated system is fertilized with mineral fertilizers exclusively (CONMIN) and one control treatment remained unfertilized (NOFERT). The CONFYM system is amended with stacked manure, supplemental mineral fertilizers, as well as chemical pesticides. Manure of the BIOORG system is slightly rotted and in BIODYN it is composted aerobically with some herbal additives. In the third crop rotation period at normal fertiliser intensity soil organic carbon (C_org, w/w) in the plough layer (0–20 cm) of the BIODYN system remained constant and decreased by 7% in CONFYM and 9% in BIOORG as compared to the starting values. With no manure application C_org-loss was severest in NOFERT (22%), followed by CONMIN together with the systems at reduced fertiliser intensity (14–16%). Soil pH tended to increase in the organic systems, whereas the integrated systems had the lowest pH values. At the end of the third crop rotation period in 1998 biological soil quality indicators were determined. Compared to soil microbial biomass in the BIODYN systems the CONFYM soils showed 25% lower values and the systems without manure application were lower by 34%. Relative to the BIODYN soils at the same fertilization intensity dehydrogenase activity was 39–42% lower in CONFYM soils and even 62% lower in soils of CONMIN. Soil basal respiration did not differ between farming systems at the same intensity, but when related to microbial biomass (qCO₂) it was 20% higher in CONFYM soils and 52% higher in CONMIN as compared to BIODYN, suggesting a higher maintenance requirement of microbial biomass in soils of the integrated systems. The manure based farming systems of the DOK trial are likely to favour an active and fertile soil. Both, C_org and biological soil quality indicators were clearly depending on the quantity and quality of the applied manure types, but soil microbial biomass and activities were much more affected than C_org.     

Survey of willingness of residents to participate in electronic waste recycling in Nigeria – A case study of mobile phone recycling

Presently, large quantities of waste mobile phones are being generated in Nigeria with a significant proportion in storage. This paper investigated the behavior of consumers in Nigeria towards this waste stream and their willingness to participate in waste mobile phones recycling. This study also assessed the willingness of consumer's to pay for a more ‘environment friendlier’ phone – the so-called ‘green phone’. We performed a principal component analysis with varimax rotation in order to condense some of our questions into a smaller set of factors. We developed a model to estimate and explain the willingness to pay (WTP) a premium for ‘green’ cell phones. The model showed that the significant predictors of willingness to pay extra for green electronics include awareness and concern about the deteriorating environment, age, and the general attitude towards the environment. About 65% of the respondents are either ‘willing’ or ‘very willing’ to drop-off no-longer-in-use electronics at a nearby recycling facility. Majority of the respondents are also very willing to pay a premium for a green phone. Considering the increasing waste generation by this sector, it has become expedient that a recycling program be introduced for these potentially harmful waste materials.     

Approaches to assess the environmental impact of organic farming with particular regard to Denmark

Ever increasing attention is being paid to the environmental impact of intensive agricultural practices, and in this context organic farming is gaining recognition as a relatively friendly production system. In general, the risk of harmful environmental effects is lower with organic than with conventional farming methods, though not necessarily so. This review examines organic farming in the light of European conditions with special regard to recent research findings from Denmark. It specifies the environmental problems caused by modern farming practices and discusses appropriate indicators for assessing their impact. A driving force-state-response (DSR) framework is employed to organise and understand the processes and mechanisms that lie behind the impact of agriculture on nature and the environment. Important groups of environmental indicators are selected that characterise (a) the aquatic environment (nitrate and phosphorus leaching), (b) the soil (organic matter, biology and structure), (c) the ecosystem (arable land, semi-cultivated areas, small biotopes and landscape), and (d) resource usage and balances (nitrogen, phosphorus, potassium and energy use).The paper also reviews several empirical studies. With regard to soil biology, organic farming is usually associated with a significantly higher level of biological activity (bacteria (Monera), fungi (Mycota), springtails (Collembola), mites (Arachnida), earthworms (Lumbricus terrestris)), due to its versatile crop rotations, reduced applications of nutrients, and the ban on pesticides. In most cases there is also a lower surplus of nutrients and less leaching with organic than with conventional farming. However, poor management (e.g., the ploughing of grass and legumes (Fabates) at the wrong time of year with no subsequent crops to capture the mineralised nitrogen), low self-sufficiency in feed, and problems with certain production systems (such as those involved in organic pig farming, i.e., grazing sows, low crop yields), can lead to a high level of leaching in some organic systems. Organic farming is faced with a need to expand and develop in line with increasing demands for organic food and growing environmental concerns. This requires closer attention to the goals, values and principles on which organic practices are based, and more research into the influence of organic farming on different aspects of the environment.     

Long-term tillage effects on atrazine and fluometuron sorption in Coastal Plain soils

Conservation tillage (CnT) management practices are known to increase levels of soil organic matter (SOM) in southeastern Coastal Plain soils. Plant residues in CnT systems accumulate at the surface and, with time, will form a layer enriched in SOM. The authors hypothesize that herbicide sorption will be highest in this SOM-enriched zone of CnT systems when compared to sorption at a similar depth in conventional tillage (CT) systems. The objective was to characterize the impact of two different tillage systems, CnT and CT, on sorption of atrazine [6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4-diamine] and fluometuron [N,N-dimethyl-N′-3-(trifluoromethyl)phenyl urea] in plots of Norfolk loamy sand (fine-loamy, siliceous thermic Typic Kandiudult). The plots have been under CnT and CT management for 18 yrs. Bulk (0–15 cm) and five equal incremental soil samples to a 15 cm depth were collected from 10 CnT and 10 CT plots, and the atrazine (ATR) and fluometuron (FLMT) sorption coefficients (K_d) were measured using batch equilibration. Significantly higher herbicide K_d values occurred in the CnT 0–3 cm samples, indicating that the highest amount of herbicide sorption occurred in the top few cm of soil. This corresponded to the stratified soil organic carbon (SOC) contents in topsoil of the CnT plots. In addition, analyses of covariance using SOC as the covariant to test for tillage effects indicated complex interactions among SOC, tillage, and depth. Those results confirm that tillage and soil depth will affect SOC contents of a Norfolk loamy sand, which correspondly will influence the magnitude of ATR and FLMT sorption.