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1.
In the Western Ghats of India, amphibians are culled at cardamom plantations since they are perceived to consume cardamom. To better understand the relationship between amphibians and cardamom, a study was undertaken at these plantations, which harbor numerous threatened and range-restricted amphibians. We undertook questionnaire surveys with 298 respondents at 148 plantations across southern India. Time-activity budget and diet analysis surveys were undertaken to determine whether amphibians really consumed cardamom. The conception that amphibians eat cardamom was found to be widespread especially among small-sized plantations, leading to negative perceptions and a lack of interest in amphibian conservation. The plantation community perceives a substantial economic loss due to amphibians, even though this is non-existent as revealed by our field surveys. These perceptions would lead to a continued intolerance of amphibian presence in plantations. A suitable outreach initiative re-affirming facts and spreading awareness on the positive role of amphibians would need to be conducted to negate this age-old myth.  相似文献   

2.
Average annual net change in soil carbon stocks under past and current management is needed as part of national reporting of greenhouse gas emissions and to evaluate the potential for soils as sinks to mitigate increasing atmospheric CO2. We estimated net soil C stock changes for US agricultural soils during the period from 1982 to 1997 using the IPCC (Intergovernmental Panel on Climate Change) method for greenhouse gas inventories. Land use data from the NRI (National Resources Inventory; USDA-NRCS) were used as input along with ancillary data sets on climate, soils, and agricultural management. Our results show that, overall, changes in land use and agricultural management have resulted in a net gain of 21.2 MMT C year(-1) in US agricultural soils during this period. Cropped lands account for 15.1 MMT C year(-1), while grazing land soil C increased 6.1 MMT C year(-1). The land use and management changes that have contributed the most to increasing soil C during this period are (1) adoption of conservation tillage practices on cropland, (2) enrollment of cropland in the Conservation Reserve Program, and (3) cropping intensification that has resulted in reduced use of bare fallow.  相似文献   

3.

Climate change in the global perspective has increased the occurrence of natural disasters, which subsequently decreased agricultural production and intensified the issue of food security. Developing countries, such as Pakistan, are facing severe food security issues, where most of the population still experiences poverty and hunger in their daily lives. Flood disasters ruin valuable land, cause agricultural production losses, and interrupt livelihood routines as expected household livelihood becomes more vulnerable. This research work focused on investigating the flood hazards vulnerability and risk of food security in the Bait community flood-prone areas of Punjab, Pakistan, with a broader aspect in contrast to previous research work. A constructed food security index composed of several IPCC and FAO factors with correlated dimensions of food security was used for the empirical estimation in this study. A composite food security index was developed through polychoric principal component analysis. To estimate the influence on the overall food security condition in the study area, a food security index was regressed on various independent variables. Estimates of the study indicated that three-fourths of household respondents in the study area are confronted with the issue of food security with changeable scale. Financing schemes, physical assets, and family type illustrated the positive influence on respondents’ food security level, whereas respondents suffering property losses owing to floods had a negative influence. The study findings suggested integrated strategies must be adopted to effectively deal with issues of food security in the scenario of increasing severity of flood disasters. Policymakers and disaster-concerned institutions need to develop disaster risk mitigation strategies by constructing new water reserves and clearing river encroachments to deal with flood disasters. Agricultural research and development authorities need to provide climate friendly seed varieties and promote particular food crops for flood prone areas to ensure food security and reduce livelihood vulnerability, specifically for the flood-prone communities.

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4.
Research on the benefits of local ecological knowledge for conservation lacks empirical data on the pathways through which local knowledge might affect natural resources management. We test whether ethnobotanical skills, a proxy for local ecological knowledge, are associated to the clearance of forest through their interaction with agricultural labor. We collected information from men in a society of gatherers–horticulturalist, the Tsimane’ (Bolivia). Data included a baseline survey, a survey of ethnobotanical skills (n = 190 men), and two surveys on agricultural labor inputs (n = 466 plots). We find a direct effect of ethnobotanical skills in lowering the extent of forest cleared in fallow but not in old-growth forest. We also find that the interaction between ethnobotanical skills and labor invested in shifting cultivation has opposite effects depending on whether the clearing is done in old-growth or fallow forest. We explain the finding in the context of Tsimane’ increasing integration to the market economy.  相似文献   

5.
With the aim of determining the main drivers of changes in nitrophytic and oligotrophic macro-lichen communities in an industrial region with a Mediterranean climate, we considered both land-cover types and atmospheric pollutants. We determined the relation between the abundance of nitrophytic and oligotrophic species with environmental factors considering the distance of influence of land-cover types. The results showed that oligotrophic species decreased in the proximity of artificial areas, barren land and agricultural areas, associated with higher concentrations of NO2 and Zn, and Ti, probably dust of industrial and agricultural origin. Nitrophytic species were positively related to all the mentioned land-cover types, and with higher concentrations of Fe and N. Magnesium, probably from ocean aerosols, was negatively related to oligotrophic species and positively to nitrophytic.  相似文献   

6.
Huang J  Long C 《Ambio》2007,36(4):343-349
Coptis teeta (Ranunculaceae), is a nontimber forest product (NTFP) that only grows in northwest Yunnan and northeast India. Its tenuous rhizome, known as "Yunnan goldthread" in the traditional Chinese medicine system, has been used as an antibacterial and as an antiinflammatory medicine for a long time. The increasing demand has resulted in commercial harvesting pressure on wild populations that were already dwindling as a result of deforestation, and wild populations are at risk of extinction. Fortunately, there exists at least 2000 hectares of a C. teeta-based agroforestry system initiated by the Lisu people in Nujiang, northwest Yunnan. This cultivation supplies us with a valuable study case for the balance between conservation and sustainable use. This case study investigated the traditional management system and history of C. teeta in Nujiang through ethnobotanical methods and field investigation. We also contrasted initial costs, economic returns, and labor demands for C. teeta cultivation with other major land uses in the region. Compared with swidden agriculture, the major land-use type in the region, C. teeta cultivation offers high economic returns and low labor and initial costs; moreover, C. teeta cultivation does not interfere with subsistence agricultural duties. This agroforestry system reflected that the cultivation of NTFPs is a conservation strategy for maintaining forest diversity, while providing a stable economic return to local forest communities, and indicates how local people manage biodiversity effectively.  相似文献   

7.
Increasing food demands are causing rapid transitions in farming systems, often involving intensified land and resource use. While transitioning has benefits regarding poverty alleviation and food outputs, it also causes environmental and social issues over time. This study aims to understand the transitions in farming systems in a region in Telangana, from 1997 to 2015, and their effect on livestock rearing and smallholder livelihoods. We also examine the impact of the transitions on lower caste groups and women in particular. We collected data using a combination of methods, i.e., a household survey, focus group discussions, and secondary data sources, to build a comprehensive picture of the transitions in the region. We found that subsistence mixed farming systems transitioned to market-orientated specialized systems over a short time span. As the transition process gained momentum, households either intensified their production or got marginalized. Technological interventions, development programs with integrated approaches, and market demand for certain agricultural produce triggered increased regional production but also led to the scarcity of water, land, and labor. The transitions marginalized some of the households, changed the role of livestock in farming, and have been inclusive of both lower caste groups and women in terms of increased ownership of large ruminants and access to technologies. However, for women specifically, further increase in workload in the context of farming is also found.  相似文献   

8.
Currently, there is a major concern about the future of nutrient loads discharged into the Baltic Sea from Polish rivers because they are main contributors to its eutrophication. To date, no watershed-scale studies have properly addressed this issue. This paper fills this gap by using a scenario-modeling framework applied in the Reda watershed, a small (482 km2) agricultural coastal area in northern Poland. We used the SWAT model to quantify the effects of future climate, land cover, and management changes under multiple scenarios up to the 2050s. The combined effect of climate and land use change on N-NO3 and P-PO4 loads is an increase by 20–60 and 24–31 %, respectively, depending on the intensity of future agricultural usage. Using a scenario that assumes a major shift toward a more intensive agriculture following the Danish model would bring significantly higher crop yields but cause a great deterioration of water quality. Using vegetative cover in winter and spring (VC) would be a very efficient way to reduce future P-PO4 loads so that they are lower than levels observed at present. However, even the best combination of measures (VC, buffer zones, reduced fertilization, and constructed wetlands) would not help to remediate heavily increased N-NO3 loads due to climate change and agricultural intensification.  相似文献   

9.
Transformation in Polish agriculture initiated by political changes in the 1990s brought about essential variations in the structure of agricultural land use. The share of cereals in cropping patterns increased, while fodder plants decreased. In addition, the level of mineral fertilization was reduced. In livestock production animal stock showed a sharp fall, which led to a decreased load of organic fertilization. The changes in cropping pattern and lower fertilization rates resulted in a decrease in the organic matter level in soils, which may impair soil quality status. These phenomena were strongly manifested in the Wielkopolska Region mainly because of the prevalence of light soils in this area, from which nutrients are readily washed out to groundwaters. It was found that many of the negative aspects of these changes in the agricultural landscape can be mitigated by establishing shelterbelts. We conclude that shelterbeds are especially effective in the control of nutrient output from a watershed.  相似文献   

10.
Microorganisms play key roles in stream ecosystems, but comparatively little is known about the resilience of freshwater bacterial communities and their susceptibility to the chemical by-products of agricultural land use. Antibiotics used in the agricultural sector are of particular concern and have been detected in waterways associated with agricultural land. Despite widespread agricultural intensification globally and the sector's high antibiotic use, the effects of agricultural antibiotic by-products on stream microbial communities have yet to be characterised. We investigated the impacts of the antibiotic monensin on microbial biofilm communities in a simulated contamination event using streamside-replicated channels. A 24-h pulse experiment in flow channels precolonised by stream biofilm microbial communities contrasted the effects of monensin concentrations ranging from realistic to extreme toxicity levels (1–550 ug L?1). Biofilm community composition was characterised immediately before and after the pulse for several weeks using automated ribosomal intergenic spacer analysis. Despite applying acutely toxic levels of monensin, only limited effects to biofilm community composition were detected immediately after antibiotic application, and these disappeared within 4 days. Rather, temporal factors drove biofilm differences, highlighting the overriding importance of wider, catchment-level, physiochemical hydrological influences on structuring freshwater biofilm communities, as opposed to localised and sporadic agricultural surface runoff contamination events containing antibiotics.  相似文献   

11.
Restoring riparian ecosystems in human-dominated landscapes requires attention to complexity, and consideration of diverse drivers, social actors, and contexts. Addressing a Global North bias, this case study uses a mixed-method approach, integrating historical data, remote sensing techniques and stakeholder perceptions to guide restoration of a river in the Western Cape, South Africa. An analysis of aerial photographs of the riparian zone from 1953 to 2016 revealed that although anthropogenic land conversion happened primarily before the 1950s, several land use and land cover classes showed marked increases in area, including: waterbodies (+ 1074%), urban areas (+ 316%), alien weeds (+ 311%) and terrestrial alien trees (+ 79%). These changes have likely been driven by land fragmentation, disturbance, and agricultural intensification. Stakeholder interviews revealed that despite the clear need for restoration, several barriers exist to successful implementation; these stem from inadequate financial resources, inappropriate funding models, institutional challenges, and a lack of techno-scientific knowledge. We give several recommendations to overcome these barriers.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01691-y.  相似文献   

12.

Ecosystem research focuses on goods and services, thereby ascribing beneficial values to the ecosystems. Depending on the context, however, outputs from ecosystems can be both positive and negative. We examined how provisioning services of wild animals and plants can switch between being services and disservices. We studied agricultural communities in Laos to illustrate when and why these switches take place. Government restrictions on land use combined with economic and cultural changes have created perceptions of rodents and plants as problem species in some communities. In other communities that are maintaining shifting cultivation practices, the very same taxa were perceived as beneficial. We propose conversion factors that in a given context can determine where an individual taxon is located along a spectrum from ecosystem service to disservice, when, and for whom. We argue that the omission of disservices in ecosystem service accounts may lead governments to direct investments at inappropriate targets.

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13.
Sludge from mining exploitation can be a source of land and water contamination in the adjacent zone. Accidents such as the break of waste mining pools in the Aznalcollar Mine (Seville, Spain) in 1998 produce important ecological disasters. In this work is presented a study of the evolution of aqua regia leachable concentration and mobility of metals in sediment samples of Guadiamar River basin from the accident date up to 2001. The application of BCR standard extraction procedures provides valuable information about the mobility and toxicity of the spill and the metal mobility in Guadiamar River polluted sediments. As a rule, themobility of several metals in the initial sludge (sulphides) is low, except for copper. Otherwise, the results of aqua regia leachable concentration and mobility of metal obtained for sediments samples indicate that the cleaning and inertisation works carried out in the zone have been adequate but insufficient, being the metal levels observed in the zone are higher than natural levels. To establish the initial impact of the spill and the mobility changes with time, mineralogical composition of the pyritic sludge and its evolution after the natural weathering and after the induction, of accelerated ageing processes by light and temperature was studied in the laboratory. Oxidation of initial sulphides to sulphates was observed. Both environmental and laboratory oxidation of the metallic sulphides increase the mobility of all metals, especially of copper, zinc and lead. The proposed laboratory procedure allows to predict the changes in mobility and therefore in toxicity that can occur at short or long term after exposure of sludge at environ-mental conditions. The mobility results in sludge and sediment samples are interpreted in terms of the mineral composition of the samples.  相似文献   

14.
River restoration is a novel paradigm of ‘mirescape’ (land-and-water-scape) management that developed along with the emergence of aquatic ecology. River restoration can be seen as the application of an ecological perspective to return rivers to nature. However, the river restoration paradigm is also the contemporary iteration of historical phases of mirescape management. We review the long and varied recorded history of the Po River in northern Italy as a case study to illustrate the transformations and common themes of mirescape management. We find, first, that significant changes in mirescape management and river condition only occur in the context of larger social, political, technological and economic transformations. Second, we show how particular cultural understandings, economic interests, technological innovations and political powers have driven particular paradigms of mirescape management. These have tended towards increasing territorial separation of wet and dry. We find, third, that these separations lead not only to increasing economic precariousness for many, but also to increasingly severe disasters. We conclude that river restoration faces social and political challenges to becoming relevant at a mirescape scale, due to its lack of integration with land management, or with current social, political, technological and economic transformations. To act on this conclusion, we suggest philosophically aligned social movements that river restoration could work with to improve impact and uptake.  相似文献   

15.
Greenhouse gas (GHG) emissions from agriculture are a significant contributor to total Danish emissions. Consequently, much effort is currently given to the exploration of potential strategies to reduce agricultural emissions. This paper presents results from a study estimating agricultural GHG emissions in the form of methane, nitrous oxide and carbon dioxide (including carbon sources and sinks, and the impact of energy consumption/bioenergy production) from Danish agriculture in the years 1990–2010. An analysis of possible measures to reduce the GHG emissions indicated that a 50–70% reduction of agricultural emissions by 2050 relative to 1990 is achievable, including mitigation measures in relation to the handling of manure and fertilisers, optimization of animal feeding, cropping practices, and land use changes with more organic farming, afforestation and energy crops. In addition, the bioenergy production may be increased significantly without reducing the food production, whereby Danish agriculture could achieve a positive energy balance.  相似文献   

16.
Agricultural land use is transforming rapidly in Southeast Asia, often supported by development policies aiming primarily at economic growth. However, the socioeconomic outcomes of these changes for smallholder farmers remain unclear. Here, we systematically review cases of agricultural land use change in Southeast Asia to assess their socioeconomic outcomes and potential trade-off and synergies in these outcomes. Of the 126 reviewed cases, we find mostly positive outcomes for income (SDG 1, 100 cases) and employment (SDG 8, 11 cases), while outcomes on health (SDG 3, 9 cases) were mixed, and outcomes for food security (SDG 2, 44 cases), gender equality (SDG 5, 13 cases), and economic equality (SDG 10, 14 cases) were mostly negative. Studies describing multiple outcomes show indications of synergies between income and food security, and between income and employment, but also potential trade-offs between income and economic equality. In addition, we find that economic land concessions result in multiple negative outcomes more often than other types of land governance regimes. The results provide evidence that economic gains from agricultural land use change often come at a cost of other dimensions of sustainable development.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01712-4.  相似文献   

17.
Particulate matter (PM) has long been recognized as an air pollutant due to its adverse health and environmental impacts. As emission of PM from agricultural operations is an emerging air quality issue, the Agricultural Particulate Matter Emissions Indicator (APMEI) has been developed to estimate the primary PM contribution to the atmosphere from agricultural operations on Census years and to assess the impact of practices adopted to mitigate these emissions at the soil landscape polygon scale as part of the agri-environmental indicator report series produced by Agriculture and Agri-Food Canada. In the APMEI, PM emissions from animal feeding operations, wind erosion, land preparation, crop harvest, fertilizer and chemical application, grain handling, and pollen were calculated and compared for the Census years of 1981–2006. In this study, we present the results for PM10 and PM2.5, which exclude chemical application and pollen sources as they only contribute to total suspended particles. In 2006, PM emissions from agricultural operations were estimated to be 652.6 kt for PM10 and 158.1 kt for PM2.5. PM emissions from wind erosion and land preparation account for most of PM emissions from agricultural operations in Canada, contributing 82% of PM10 and 76% of PM2.5 in 2006. Results from the APMEI show a strong reduction in PM emissions from agricultural operations between 1981 and 2006, with a decrease of 40% (442.8 kt) for PM10 and 47% (137.7 kt) for PM2.5. This emission reduction is mainly attributed to the adoption of conservation tillage and no-till practices and the reduction in the area of summerfallow land.

Implications: Increasing sustainability in agriculture often means adapting management practices to have a beneficial impact on the environment while maintaining or increasing production and economic benefits. We developed an inventory of primary PM emissions from agriculture in Canada to better quantify the apportionment, spatial distribution, and trends for Census years 1981–2006. We found major reductions of 40% in PM10 and 47% in PM2.5 emissions over the 25-yr period as a co-benefit of increasing carbon sequestration in agricultural soils. Indeed, farmers adopted conservation tillage/no-till practices, increased usage of cover crops, and reduced summerfallow, in order to increase soil organic matter and reduce carbon dioxide emissions, which also reduced primary PM emissions, although the agricultural production increased over the period.  相似文献   

18.
We calculated farm, land, and soil N-budgets for countries in Europe and the EU27 as a whole using the agro-economic model CAPRI. For EU27, N-surplus is 55 kg N ha−1 yr−1 in a soil budget and 65 kg N2O–N ha−1 yr−1 and 67 kg N ha−1 yr−1 in land and farm budgets, respectively. NUE is 31% for the farm budget, 60% for the land budget and 63% for the soil budget. NS values are mainly related to the excretion (farm budget) and application (soil and land budget) of manure per hectare of total agricultural land. On the other hand, NUE is best explained by the specialization of the agricultural system toward animal production (farm NUE) or the share of imported feedstuff (soil NUE). Total N input, intensive farming, and the specialization to animal production are found to be the main drivers for a high NS and low NUE.  相似文献   

19.
Jansson U  Kautsky U  Miliander S 《Ambio》2006,35(8):505-512
Production and consumption of food and in a rural area over the last 400 years were reconstructed for a parish in south east Sweden. This was based on a number of different data sources, including historical maps and official demographic and agricultural statistics. Changes in population (and thus consumption) and the production from arable land and livestock were calculated and used to provide an estimate of the area's supply and demand over time, and of the historical sustainability of the area. Overall food productivity was remarkably constant over time, at approximately 0.04 kgC m(-2) y(-1), despite recent changes in population size and the area of cultivated land. The empirical results from the past and the present, together with the future land changes due to shoreline displacement were used to predict the situation in the future. These final estimates can be used in the assessment of risk for exposure to contaminated food for the future population in the area.  相似文献   

20.
John C. Moore 《Ambio》2021,50(7):1295
This paper reflects on the legacy of the Ambio papers by Sombroek et al. (1993), Turner et al. (1994), and Brussaard et al. (1997) on the study of agricultural land use and its impacts on global carbon storage and nutrient dynamics. The papers were published at a time of transition in ecology that involved the integration of humans as components of ecosystems, the formulation of the ecosystem services, and emergence of sustainability science. The papers offered new frameworks to studying agricultural land use across multiple scales in a way that captured causality from interacting components of the system. Each paper argued for more comprehensive data sets; foreseeing the power of network-based science, the potential of molecular technologies to assess biodiversity, and advances in remote sensing. The papers have contributed both conceptual framings and methodological approaches to an ongoing movement to identify a pathway to study agricultural land use and environmental change that fit within the concepts of ecosystem services, planetary boundaries and sustainable development goals.  相似文献   

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