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1.
Few initiatives to preserve and enhance biodiversity on farmland have been as thoroughly evaluated and debated as the agri-environment schemes (AES). Yet, little is known how confounding factors co-varying with the specific AES measures may affect species responses. Here, we quantify the influence of one such factor, the time since transition to organic farming, on moth diversity patterns. We found that species richness and abundance of moths were higher on new organic farms (years since transition ≤6) compared to old organic (≥15 years) and conventional farms, indicating a transient diversity peak. This correlates with the abundance patterns of the weed Cirsium arvense, which also reached its highest densities on new organic farms. Weeds such as C. arvense constitute a notorious problem in organic farming. However, they also provide various resources for farmland biodiversity, and our results strongly suggest that the transient weed peak may be important in influencing the parallel peak among the moths. This stresses the problem in balancing out production and conservation values. More generally, our results show that rather than having static effects on the environment, AES can have an important temporal component and result in a dynamic interplay between different trophic levels.  相似文献   

2.
Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional) and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short-term effects on aphid densities but long-term negative effects on biological pest control. Therefore conventional farmers should restrict insecticide applications to situations where thresholds for pest densities are reached.  相似文献   

3.
It has been suggested that biodiversity in agroecosystems depends on both landscape heterogeneity and farm management, but at the same time, studies of biodiversity in relation to both landscape variables and farm management are rare. We investigated the species richness of plants, butterflies, carabids, rove beetles and the diversity of spiders in cereal fields, leys (grass and clover crop) and semi-natural pastures at 16 farms in Central East Sweden. The farms were divided into eight pairs of one conventional and one organic farm to enable us to separate the effects of landscape and farm management on biodiversity. The pairing was based on land use, location, and landscape features. Species richness of different taxonomic groups was generally not correlated. There were no differences in species richness between the farming systems, except for carabids that had higher numbers of species on conventional farms. The species richness generally increased with landscape heterogeneity on a farm scale. Habitat type had a major effect on the species richness for most groups, with most species found in pastures and leys. The correlations between species richness and landscape variables on a farm scale, and not on a scale of multiple farms, identify farmers as the important decision-maker in conservation issues for these taxonomic groups. We discuss the role of species richness of pests' natural enemies for biological control and conservation strategies of the more common species in the agricultural landscape.  相似文献   

4.
Agri‐environment schemes (AES) have been suggested to counter negative effects of agricultural intensification and enhance farmland biodiversity, but evaluations have produced inconsistent results. We suggest that this is partly a consequence of scale‐dependence, i.e. that the consequence of organic farming will differ depending on the scale of uptake in a particular landscape. To test our hypothesis on diversity of forbs, we designed a landscape scale study using spatially explicit information about the Swedish AES for organic farming. The study system consisted of uncultivated field borders along paired fields (organic and conventional) in matched landscapes with either a high or a low proportion of organic faming, allowing separate tests of the effects of farming practice at the local and the landscape scale. The local effect of organic farming was consistently strong, with higher diversity in borders adjoining organic fields, most likely due to the lack of herbicide use on organically managed farmland. Thus, we show that not only the proportion of semi‐natural habitat is important for farmland biodiversity, but that also the management of cropland can influence the diversity in semi‐natural habitats. Furthermore, forb richness was also higher in borders situated in landscapes with a high proportion of organic land, irrespectively of local management, possibly as a result of dispersal of mainly annual plant species from the organically managed fields into the borders (mass effect). Our results demonstrate that farming practice at a local and a landscape scale independently can influence plant species richness, indicating that organic farming can influence diversity also at larger spatial scales and outside the organically managed land. Our study highlight the importance of studying multiple scales, including both local and landscape factors to provide a better understanding of biodiversity patterns.  相似文献   

5.
Organic farming, a low intensity system, may offer benefits for a range of taxa, but what affects the extent of those benefits is imperfectly understood. We explored the effects of organic farming and landscape on the activity density and species density of spiders and carabid beetles, using a large sample of paired organic and conventional farms in the UK. Spider activity density and species density were influenced by both farming system and surrounding landscape. Hunting spiders, which tend to have lower dispersal capabilities, had higher activity density, and more species were captured, on organic compared to conventional farms. There was also evidence for an interaction, as the farming system effect was particularly marked in the cropped area before harvest and was more pronounced in complex landscapes (those with little arable land). There was no evidence for any effect of farming system or landscape on web-building spiders (which include the linyphiids, many of which have high dispersal capabilities). For carabid beetles, the farming system effects were inconsistent. Before harvest, higher activity densities were observed in the crops on organic farms compared with conventional farms. After harvest, no difference was detected in the cropped area, but more carabids were captured on conventional compared to organic boundaries. Carabids were more species-dense in complex landscapes, and farming system did not affect this. There was little evidence that non-cropped habitat differences explained the farming system effects for either spiders or carabid beetles. For spiders, the farming system effects in the cropped area were probably largely attributable to differences in crop management; reduced inputs of pesticides (herbicides and insecticides) and fertilisers are possible influences, and there was some evidence for an effect of non-crop plant species richness on hunting spider activity density. The benefits of organic farming may be greatest for taxa with lower dispersal abilities generally. The evidence for interactions among landscape and farming system in their effects on spiders highlights the importance of developing strategies for managing farmland at the landscape-scale for most effective conservation of biodiversity.  相似文献   

6.
Japanese encephalitis (JE) is a mosquito-borne zoonotic disease that has pigs as the major amplifying hosts. It is the most important cause of viral encephalitis in people in Nepal and is spreading in its geographic distribution in that country. Pig farming is increasing in Nepal due to reducing cultural biases against pigs and government programs to support pig farming for poverty alleviation. Major strategies for JE prevention and control include education, vector control, and immunization of people and pigs. This study used a survey of 400 pig farmers in 4 areas of Nepal with different JE and pig farming histories to explore regional variations in farmer awareness and actions towards JE, the association of awareness and actions with farm and farmer variables, and the implications of these associations for public health education. Exposure to JE risk factors was common across pig farms and pig farming districts but there were significant district level differences in knowledge and practices related to on-farm JE risk reduction. Social factors such as literacy, gender, and cultural practices were associated with farmer attitudes, knowledge and practices for JE control. JE vaccine uptake was almost non-existent and mosquito control steps were inconsistently applied across all 4 districts. Income was not a determining factor of the differences, but all farmers were very poor. The low uptake of vaccine and lack of infrastructure or financial capacity to house pigs indoors or away from people suggest that farmer personal protection should be a priority target for education in Nepal. This study re-enforces the need to attack root causes of people’s personal disease prevention behaviours and take into account local variation in needs and capacities when designing health or agriculture education programs.  相似文献   

7.
《Global Change Biology》2017,23(11):4946-4957
Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than species richness, and whether impacts differ across spatial scales and landscape contexts. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity (communities within fields), and regional diversity (communities across fields) of arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in‐field plant diversity enhanced arthropod abundance, particularly for rare taxa. This resulted in increased richness but decreased evenness. While these responses were stronger at local relative to regional scales, richness and abundance increased at both scales, and richness on farms embedded in complex relative to simple landscapes. Overall, both organic farming and in‐field plant diversification exerted the strongest effects on pollinators and predators, suggesting these management schemes can facilitate ecosystem service providers without augmenting herbivore (pest) populations. Our results suggest that organic farming and plant diversification promote diverse arthropod metacommunities that may provide temporal and spatial stability of ecosystem service provisioning. Conserving diverse plant and arthropod communities in farming systems therefore requires sustainable practices that operate both within fields and across landscapes.  相似文献   

8.
Populations of farmland birds are under pressure as a result of agricultural intensification. It has been proposed that less intensive approaches to farming, such as organic farming methods, may halt these population declines. In addition, organic farmers may have a more positive attitude towards nature and the environment which can possibly also have positive effects on the populations of breeding birds. We have compared the attitude of conventional and organic farmers towards the presence of Barn Swallows Hirundo rustica and the abundance of breeding Barn Swallows on organic and conventional arable farms in the Netherlands. We found that the abundance of breeding Barn Swallows did not differ between these two types of farms an that both organic and conventional farmers had a positive attitude towards the presence of Barn Swallows on their farms. Our results show that organic farming does not attract more Barn Swallows. However, agricultural intensification could have resulted in lower breeding success and, consequently, population declines, although there may be other contributory factors as well.  相似文献   

9.
It has been suggested that organic farming may benefit farmland biodiversity more in landscapes that have lost a significant part of its former landscape heterogeneity. We tested this hypothesis by comparing bird species richness and abundance during the breeding season in organic and conventional farms, matched to eliminate all differences not directly linked to the farming practice, situated in either homogeneous plains with only a little semi-natural habitat or in heterogeneous farmland landscapes with abundant field borders and semi-natural grasslands. The effect of farm management on species richness interacted with landscape structure, such that there was a positive relationship between organic farming and diversity only in homogeneous landscapes. This pattern was mainly dependent on the species richness of passerine birds, in particular those that were invertebrate feeders. Species richness of non-passerines was positively related to organic farming independent of the landscape context. Bird abundance was positively related to landscape heterogeneity but not to farm management. This was mainly because the abundance of passerines, particularly invertebrate feeders, was positively related to landscape heterogeneity. We suggest that invertebrate feeders particularly benefit from organic farming because of improved foraging conditions through increased invertebrate abundances in otherwise depauperate homogeneous landscapes. Although many seed-eaters also benefit from increased insect abundance, they may also utilize crop seed resources in homogeneous landscapes and conventional farms. The occurrence of an interactive effect of organic farming and landscape heterogeneity on bird diversity will have consequences for the optimal allocation of resources to restore the diversity of farmland birds.  相似文献   

10.
To prevent further biodiversity loss as a result of intensive agricultural practices, Agri-Environmental Schemes (AES) have been implemented on European farmland. Unfortunately these AES have not always been effective in terms of biodiversity and farmer participation. In an effort to improve the AES programme the Dutch government switched from an individual application system to a collective application system for AES payments in 2016. The goal of this paper is to analyse how the resilience of the land use system in terms of farmer participation in the AES and biodiversity is affected by the value farmers attach to biodiversity, and whether the shift from an individual to collective AES will affect the resilience of the land use system. We constructed a multi-objective mathematical programming model in which farmers maximise utility. Farmers are linked through their common effect on biodiversity. In the collective application system payments are only available when the biodiversity in the region is above a certain threshold. Simulation results show no difference in farmer participation and biodiversity between the individual application system and the collective application system when biodiversity weights are high. The land use system loses its resilience in terms farmer participation in the AES and biodiversity if we lower the biodiversity weights, this effect is stronger in the collective AES programme.  相似文献   

11.
Coffee with diverse shade trees is recognized as conserving greater biodiversity than more intensive production methods. Sustainable certification has been proposed as an incentive to conserve shade grown coffee. With 40% of global coffee production certified as sustainable, evidence is needed to demonstrate whether certification supports the environmental benefits of shade coffee. Environmental and economic data were taken from 278 coffee farms in Nicaragua divided between non-certified and five different sustainable certifications. Farms were propensity-score matched by altitude, area of coffee and farmer education to ensure comparability between non-certified and certified farms. Farms under all certifications had better environmental characteristics than non-certified for some indicators, but none were better for all indicators. Certified farms generally received better prices than non-certified farms. Farms with different certifications had different investment strategies; C.A.F.E. Practice farms had high investment and high return strategies, while Utz and Organic farms had low investment, low productivity strategies. Tree diversity was inversely related to productivity, price and net revenue in general, but not for certified farms that received higher prices. Certification differentiates farms with better environmental characteristics and management, provides some economic benefits to most farmers, and may contribute to mitigating environment/economic trade-offs.  相似文献   

12.
The generally higher biodiversity on organic farms may be influenced by management features such as no synthetic pesticide and fertilizer inputs and/or by differences in uncropped habitat at the site and landscape scale. We analysed bird and habitat data collected on 48 paired organic and conventional farms over two winters to determine the extent to which broad-scale habitat differences between systems could explain overall differences in farmland bird abundance. Density was significantly higher on organic farms for six out of 16 species, and none on conventional. Total abundance of all species combined was higher on organic farms in both years. Analyses using an information-theoretic approach suggested that both habitat extent and farm type were important predictors only for starling and greenfinch. Organic farming as currently practised may not provide significant benefits to those bird species that are limited by winter food resources, in particular, several declining granivores.  相似文献   

13.
While many studies have demonstrated that organic farms support greater levels of biodiversity, it is not known whether this translates into better provision of ecosystem services. Here we use a food-web approach to analyse the community structure and function at the whole-farm scale. Quantitative food webs from 10 replicate pairs of organic and conventional farms showed that organic farms have significantly more species at three trophic levels (plant, herbivore and parasitoid) and significantly different network structure. Herbivores on organic farms were attacked by more parasitoid species on organic farms than on conventional farms. However, differences in network structure did not translate into differences in robustness to simulated species loss and we found no difference in percentage parasitism (natural pest control) across a variety of host species. Furthermore, a manipulative field experiment demonstrated that the higher species richness of parasitoids on the organic farms did not increase mortality of a novel herbivore used to bioassay ecosystem service. The explanation for these differences is likely to include inherent differences in management strategies and landscape structure between the two farming systems.  相似文献   

14.
Mixed crop–livestock (MC–L) farming has gained broad consensus as an economically and environmentally sustainable farming system. Working on a Charolais-area suckler cattle farms network, we subdivided the 66 farms of a constant sample, for 2 years (2010 and 2011), into four groups: (i) ‘specialized conventional livestock farms’ (100% grassland-based farms (GF), n=7); (ii) ‘integrated conventional crop–livestock farms’ (specialized farms that only market animal products but that grow cereal crops on-farm for animal feed, n=31); (iii) ‘mixed conventional crop–livestock farms’ (farms that sell beef and cereal crops to market, n=21); and (iv) organic farms (n=7). We analyse the differences in structure and in drivers of technical, economic and environmental performances. The figures for all the farms over 2 years (2010 and 2011) were pooled into a single sample for each group. The farms that sell crops alongside beef miss out on potential economies of scale. These farms are bigger than specialized beef farms (with or without on-farm feed crops) and all types of farms show comparable economic performances. The big MC–L farms make heavier and consequently less efficient use of inputs. This use of less efficient inputs also weakens their environmental performances. This subpopulation of suckler cattle farms appears unable to translate a MC–L strategy into economies of scope. Organic farms most efficiently exploit the diversity of herd feed resources, thus positioning organic agriculture as a prototype MC–L system meeting the core principles of agroecology.  相似文献   

15.
Agricultural intensification in Europe has affected farmland bird populations negatively, both during summer and winter. Although the migratory period poses separate challenges on birds than breeding and wintering, the consequences of farming practices for birds during migration remain poorly investigated. We monitored abundance and species richness of migratory birds in autumn at matched pairs of organic and conventional farms situated either in intensively farmed open plains (homogeneous landscapes) or in small‐scale farming landscapes (heterogeneous landscapes) in southern Sweden. Total bird density did not differ between landscape types but was marginally higher on organic compared to conventional farms. When including taxonomic status in the model (passerines vs non‐passerines), we found significantly more birds on organic farms, and more non‐passerines in the homogeneous landscapes. The effect of farming practice and landscape type on density differed between functional groups. Omnivore density was higher in the homogeneous landscapes, and invertebrate feeders were marginally more abundant on organic farms. The effects of farming practice on the overall species richness and on the density of granivorous birds were landscape dependent. In the homogeneous landscapes, organic farms held a higher number of species and density of granivorous birds than conventional farms, but there was no such difference in the heterogeneous landscapes. Thus, organic farming can enhance abundance and species richness of farmland birds during migration, but the effect differs between landscape types and species. The effectiveness of organic farming was highest in the homogeneous landscape making it important to promote organic farming there. However, for some species during migration, increased heterogeneity in homogeneous landscapes may have negative effects. We propose that migratory bird diversity in homogeneous landscapes may be best preserved by keeping the landscape open, but that a reduced agricultural intensity, such as organic farming, should be encouraged.  相似文献   

16.
PurposeThe Kingdom of Saudi Arabia is continuously in search of environment-friendly farming practices since mass-scale agriculture was initiated. It is imperative to gauge to the level of awareness of the farmers on the agricultural practices causing environmental issue in order to devise new agricultural extension programs. This research aims to identify the attitudes of farmers towards agriculture and environment in Al-Ghat area of Saudi Arabia.MethodologyA simple random sample of 110 farms truly representing the farming community was drawn to meet the objectives of the study. Data were collected by using the pre-tested questionnaire during the face-to-face interviews. In order to understand the message of study, data were analyzed for percentages, arithmetic average and standard deviation in addition to the simple Pearson correlation coefficient.ResultsThe results showed that the high proportion (87.3%) of farmers was interested in continuing to work farm and 77.3% of farmers did not consider adopting agriculture their main occupation. The findings of the survey reveal that some 55.5% of the respondent farmers were aware of the agricultural practices and their relation to the environment. Some 57.3% of the surveyed farmers are aware of potential benefits of enhanced utilization of agricultural organic wastes. However, main profession, farm employment (as the independent variables) showed a significant positive correlation with the attitudes of farmers towards their working in agriculture (as a dependent variable). Also a significant negative relationship between the educational levels and the attitudes of the farmers towards working in agriculture was noticed. The study also indicated a significant correlation between education and the degree of awareness of agricultural practices related to the environment and maximizing the optimum utilization of agricultural waste i.e. organic residues.ConclusionsThe study suggested the need for new awareness and orientation programs to educate farmers and extension workers, highlighting the environment- friendly agricultural practices.Recommendation: There is need to offer incentives and facilities to keep the farmers stay in the farming business. Extension staff must keep educating them on beneficial features of organic farm waste and crop residues as organic fertilizers.  相似文献   

17.
Habitat destruction and degradation are important drivers of biodiversity loss within agro-ecosystems. However, little is known about the effect of farming practices and the value of woody hedgerows on Lepidoptera in North America. The purpose of this work was to study moth diversity in woody hedgerows and croplands of organic and conventional farms. In addition, the influence of vegetation composition and abiotic variables on species richness, abundance, and composition was examined. Moths were sampled with light traps during six weeks in the summer of 2001. Vegetation data and abiotic variables were obtained for all sites. In total, 26,020 individuals from 12 families and 408 species were captured. Most species were uncommon. Only 35 species included >100 individuals while for 71% of species <10 individuals were found. The Noctuidae represented 221 species and 85% of all individuals captured. Woody hedgerows harbored more species and in greater number than croplands. There was no significant difference in moth diversity between organic and conventional farms, except that the Notodontidae were significantly more species rich in organic than in conventional sites. Results show that species richness, abundance, and composition were greatly influenced by habitat types (hedgerow versus crop field) and abiotic variables (minimum temperature which was correlated to moon illumination, rainfall, and cloud cover). Moth species composition was significantly correlated to vegetation composition. This study broadens our understanding of the factors driving moth diversity and expands our knowledge of their geographic range. The maintenance of noncrop habitats such as woody hedgerows within agro-ecosystems seems paramount to preserving the biodiversity and abundance of many organisms, including moths.  相似文献   

18.
Agricultural intensification may result in important shifts in insect community composition and function, but this remains poorly explored. Studying how groups of species with shared traits respond to local and landscape scale land-use management can reveal mechanisms behind such observed impacts. We tested if ground beetles (Coleoptera: Carabidae) divided into trait groups based on body sizes, wing morphologies and dietary preferences respond differently to farming practise (organic and conventional), farming intensity (measured as yield) and landscape complexity (measured as the proportion of arable land within a 1,000 m radius) across Europe. We used data from 143 farms in five regions in northern and central Europe. Organic farms did not differ in abundance or richness of any trait group compared to conventional farms. As farm scale intensity (yield) increased, overall abundance of beetles decreased, but abundances of small and medium sized beetles, as well as that of wingless beetles, were unaffected. Overall species richness was not affected by yield, whereas consideration of traits revealed that phytophagous and omnivorous beetles were less species rich on farms with high yields. Increasing the proportion of arable land in the landscape increased overall beetle abundance. This was driven by an increase in omnivorous beetles. The total species richness was not affected by an increase in the proportion arable land, although the richness of wingless beetles was found to increase. Potential effects on ecosystem functioning need to be taken into account when designing schemes to maintain agricultural biodiversity, because species with different ecological traits respond differently to local management and landscape changes.  相似文献   

19.
Intensive pig production systems are a source of stress, which is linked to reduced animal welfare and increased antimicrobial use. As the gatekeepers of the welfare of the animals under their care, farmers are seen as the stakeholder responsible for improving animal welfare. The aim of this study was to explore the knowledge and attitudes of pig farmers towards pig welfare and the impact of such attitudes on farmers' selection of management strategies on the farm. We conducted in-depth semi-structured interviews with 44 pig farmers in one of the main pig producing regions of Brazil. Interviews covered knowledge and attitudes towards pig sentience and behaviour and welfare-related issues commonly observed in intensive pig farms (belly-nosing, fights, tail-biting, diarrhoea and castration without pain control) and farmers' conception and attitudes towards pig welfare. We identified many management and animal-based indicators of poor welfare, such as the use of painful and stressful management practices and use of environments that limit the expression of natural behaviours. However, most farmers were satisfied with animal welfare standards at their farms. Farmers' perceptions are aligned with their understanding of animal welfare. Although they identified all the dimensions that impact the welfare of a pig on a farm (affect, biological functioning and naturalness), their social reality, industry demands and available advice pushed them to perceive their range of action limited to biological and environmental aspects of the animals that do not necessarily benefit affective state. This precluded farmers from making associations between good health and the animal's ability to express a full behavioural repertoire, as well as from viewing abnormal behaviours as problems. The negative consequences for the welfare of the animals were commonly alleviated by routines that relied on constant use of medication, including high dependence on antibiotics. Expressions of estrangement from the production chain were common voices among the participants. This suggests that farmers may not be sufficiently informed or engaged in responding to consumers' expectations and commitments made by companies, which can pose a severe economic risk for farmers. The findings of this study indicate that economic, technical and social factors restrict farmers' autonomy and their ability to perform their role as stewards of animal welfare. (Re)connecting different human, animal and environmental interests may be a step to changing this scenario.  相似文献   

20.
Organic farming improves pollination success in strawberries   总被引:2,自引:0,他引:2  
Pollination of insect pollinated crops has been found to be correlated to pollinator abundance and diversity. Since organic farming has the potential to mitigate negative effects of agricultural intensification on biodiversity, it may also benefit crop pollination, but direct evidence of this is scant. We evaluated the effect of organic farming on pollination of strawberry plants focusing on (1) if pollination success was higher on organic farms compared to conventional farms, and (2) if there was a time lag from conversion to organic farming until an effect was manifested. We found that pollination success and the proportion of fully pollinated berries were higher on organic compared to conventional farms and this difference was already evident 2-4 years after conversion to organic farming. Our results suggest that conversion to organic farming may rapidly increase pollination success and hence benefit the ecosystem service of crop pollination regarding both yield quantity and quality.  相似文献   

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