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1.
A number of policy tools are used to reduce soil erosion from agricultural lands in the USA, including education and technical assistance, financial assistance, land retirement, and conservation compliance requirements. Education and technical assistance by public and private sources can be effective in promoting the adoption of conservation tillage by farmers for whom that practice will be profitable. Financial incentives may be necessary to induce the voluntary adoption of conservation tillage by farmers for whom the practice would not be more profitable than conventional tillage but on whose land the use of conservation tillage would provide substantial offsite benefits.  相似文献   

2.
Conservation practices are implemented on farm fields in the USA through Farm Bill programs; however, there is a need for greater verification that these practices provide environmental benefits (e.g., water quality). This study was conducted to assess the impact of Farm Bill eligible conservation practices on soluble P (SP) and total P (TP) losses from four fields that were monitored between 2004 and 2013. No-tillage doubled SP loading compared to rotational tillage (e.g., tilled only before planting corn); however, no-tillage decreased TP loading by 69 % compared to rotational tillage. Similarly, grassed waterways were shown to increase SP loads, but not TP loads. A corn–soybean–wheat–oat rotation reduced SP loads by 85 % and TP loads by 83 % compared to the standard corn–soybean rotation in the region. We can potentially attain TP water quality goals using these Farm Bill practices; however, additional strategies must be employed to meet these goals for SP.  相似文献   

3.
Ecological restoration and conservation are primary components of sustainable development around the world, particularly during the contemporary era of climate change. However, restoration and conservation are not free; they consume huge amounts of resources that would otherwise support social and economic development. Therefore, excessive conservation creates a risk of creating rather than eliminating poverty. Unfortunately, scientists have largely ignored the balance between these contrasting goals. Here, we discuss the concept of finding the threshold that represents a suitable balance between ecological conservation and economic development, thereby maximizing the benefits for both humans and the environment and promoting sustainable development. To demonstrate the concept, we examined China’s ecological restoration achievements and discussed some of the unforeseen negative consequences that accompanied these achievements to discuss how future policies could better balance ecological and socioeconomic goals.  相似文献   

4.
Agricultural management affects the movement of atrazine in soil and leaching to groundwater. The objective of this study was to determine atrazine adsorption in a soil after 20 years of atrazine application under agronomic management practices differing in tillage practice (conventional and zero tillage), residue management (with and without residue retention) and crop rotation (wheat-maize rotation and maize monoculture). Atrazine sorption was determined using batch and column experiments. In the batch experiment, the highest distribution coefficient Kd (1.1 L kg?1) at 0–10 cm soil depth was observed under zero tillage, crop rotation and residue retention (conservation agriculture). The key factor in adsorption was soil organic matter content and type. This was confirmed in the column experiment, in which the highest Kd values were observed in treatments with residue retention, under either zero or conventional tillage (0.81 and 0.68 L kg?1, respectively). Under zero tillage, the fact that there was no soil movement helped to increase the Kd. The increased soil organic matter content with conservation agriculture may be more important than preferential flow due to higher pore connectivity in the same system. The soil's capacity to adsorb 2-hydroxyatrazine (HA), an important atrazine metabolite, was more important than its capacity to adsorb atrazine, and was similar under all four management practices (Kd ranged from 30 to 40 L kg?1). The HA adsorption was attributed to the type and amount of clay in the soil, which is unaffected by agronomic management. Soils under conservation agriculture had higher atrazine retention potential than soils under conventional tillage, the system that predominates in the study area.  相似文献   

5.
Laboratory incubations were performed in order to evaluate the dissipation of the proherbicide isoxaflutole in seedbed layer soil samples from conventional and conservation tillage systems and in maize and oat residues left at the soil surface under conservation tillage. The effects of temperature and water pressure head on radiolabelled isoxaflutole degradation were studied for each sample for 21 d. Mineralisation of isoxaflutole was low for all samples and ranged from 0.0% to 0.9% of applied 14C in soil samples and from 0.0% to 2.4% of applied 14C in residue samples. In soil samples, degradation half-life of isoxaflutole ranged from 9 to 26 h, with significantly higher values under conservation tillage. In residue samples, degradation half-life ranged from 3 to 31 h, with significantly higher values in maize residues, despite a higher mineralisation and bound residue formation than in oat residues. Whatever the sample, most of the applied 14C remained extractable during the experiment and, after 21 d, less than 15% of applied 14C were unextractable. This extractable fraction was composed of diketonitrile, benzoic acid derivative and several unidentified metabolites, with one of them accounting for more than 17% of applied 14C. This study showed that tillage system design, including crop residues management, could help reducing the environmental impacts of isoxaflutole.  相似文献   

6.
Samples of benthic invertebrates from four pairs of streams in southwestern Ontario collected monthly from May through August 1991, and once during the subsequent autumn and winter, demonstrated that conservation tillage practices have a remedial effect on the water quality of adjacent streams as indicated by biotic, rather than physical or chemical, parameters. One stream of each pair drained a basin under conventional tillage (CONV, mainly mouldboard ploughing), the other primarily under conservation tillage (CONS). The paired drainage basins were otherwise similar to one another in type of crops grown, as well as size, topography, soils and hydrology. CONS streams yielded a greater variety of Insecta but fewer taxa of Mollusca, Annelida and Crustacea than did samples from CONV streams. Both kick-net and Surber samples from CONS streams yielded significantly more taxa, more kinds of Ephemeroptera, Plecoptera and Trichoptera, and lower Hilsenhoff Biotic Index scores than did samples from CONV streams. Kick samples from CONS streams were significantly more similar to expected reference communities in overall taxonomic composition. Surber samples from CONS streams contained significantly larger numbers of invertebrates. The relatively greater abundances of infaunal species, especially Tubificidae and Chironomini, in CONV streams suggest greater accumulation of fine sediment particles. Conditions during low flow appear to have the greatest influence on the composition of benthic invertebrate communities. The results of the study indicate that conservation tillage practices have a beneficial effect on the quality of surface waters.  相似文献   

7.
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   

8.
High levels of species richness and endemism make Myanmar a regional priority for conservation. However, decades of economic and political sanctions have resulted in low conservation investment to effectively tackle threats to biodiversity. Recent sweeping political reforms have placed Myanmar on the fast track to economic development—the expectation is increased economic investments focused on the exploitation of the country’s rich, and relatively intact, natural resources. Within a context of weak regulatory capacity and inadequate environmental safeguards, rapid economic development is likely to have far-reaching negative implications for already threatened biodiversity and natural-resource-dependent human communities. Climate change will further exacerbate prevailing threats given Myanmar’s high exposure and vulnerability. The aim of this review is to examine the implications of increased economic growth and a changing climate within the larger context of biodiversity conservation in Myanmar. We summarize conservation challenges, assess direct climatological impacts on biodiversity and conclude with recommendations for long-term adaptation approaches for biodiversity conservation.  相似文献   

9.
Ding G  Novak JM  Herbert S  Xing B 《Chemosphere》2002,48(9):897-904
Sorption and desorption are two important processes that influence the amount of pesticides retained by soils. However, the detailed sorption mechanisms as influenced by soil tillage management are unclear. This study examined the sorption and desorption characteristics of metolachlor [2-chloro-N-(2-ethyl-6-methyphenyl)-N-(2-methoxy-1-methylethyl)-acetamide] using the soil samples collected from the long-term conservation tillage (CnT) and conventional tillage (CT) research plots established in 1979 in Darlinton, SC. Humic acid (HA) and humin were extracted from the soils and used in the sorption experiments along with the whole soil samples. The sorption experiments were conducted using a batch-equilibration method. Three sequential desorption rinses were carried out following the sorption experiments. By comparing metolachlor sorption and desorption results we observed hysteresis for all soil samples and their organic matter fractions. Sorption nonlinearity (N) and hysteresis were dependent on the structure and composition of soil organic matter (SOM), e.g., Freundlich isotherm exponents (N) of HA and humin from CnT were higher than those of CT treatment, which may be related to high aromaticity of SOM fractions in CT treatment. Sorption capacity (K'f) was positively correlated with soil organic carbon (SOC) content. These results show that long-term tillage management can greatly affect metolachlor sorption and desorption behavior probably by qualitative differences in the structural characteristics of the humic substances.  相似文献   

10.
Laboratory studies were conducted to evaluate the effects of temperature and water pressure head on the degradation of the diketonitrile metabolite (DKN) of isoxaflutole during 84 d in samples collected in a loamy soil under conventional (CT) and conservation (MT) tillage systems. Soil temperature was the major factor controlling DKN degradation in the two tillage systems. The shortest half-lives (T1/2) were measured in the seedbed samples under MT at 25 °C and −33 cm water pressure head. We found that mouldboard ploughing under CT was responsible for the spatial variability of herbicide degradation properties, whereas under MT herbicide degradation was associated to the vertical distribution of organic matter.  相似文献   

11.
Donald S. Maier 《Ambio》2018,47(4):477-492
Pursuit of economic gain has sponsored much of our planet’s despoliation. Yet conservation increasingly operates as an economic sector that markets biodiversity, ecosystems, and nature as natural capital, service provider, or option value. This essay first elucidates what basic moral theory says about the principle that the goodness of biodiversity and nature is largely economic. It explains why economic valuations may be morally unimportant, inapt for environmental goods, and subversive of more important ideals. It also shows why neither econometric notions of option value nor Daniel Faith’s qualitative one credibly applies. The essay then turns to what an economic conception of goodness implies for conservation practice. It refers to two prominent conservation organizations, whose conservation principles match the market-based ones of the World Business Council on Sustainable Development’s. The environmental record of the latter organization’s practices according to these principles predicts what their adoption for conservation entails.  相似文献   

12.
Siikamäki J  Newbold SC 《Ambio》2012,41(Z1):78-89
Deforestation is the second largest anthropogenic source of carbon dioxide emissions and options for its reduction are integral to climate policy. In addition to providing potentially low cost and near-term options for reducing global carbon emissions, reducing deforestation also could support biodiversity conservation. However, current understanding of the potential benefits to biodiversity from forest carbon offset programs is limited. We compile spatial data on global forest carbon, biodiversity, deforestation rates, and the opportunity cost of land to examine biodiversity conservation benefits from an international program to reduce carbon emissions from deforestation. Our results indicate limited geographic overlap between the least-cost areas for retaining forest carbon and protecting biodiversity. Therefore, carbon-focused policies will likely generate substantially lower benefits to biodiversity than a more biodiversity-focused policy could achieve. These results highlight the need to systematically consider co-benefits, such as biodiversity in the design and implementation of forest conservation programs to support international climate policy.  相似文献   

13.
In human-populated landscapes worldwide, domestic dogs (Canis lupus familiaris) are the most abundant terrestrial carnivore. Although dogs have been used for the protection of livestock from wild carnivores, they have also been implicated as predators of livestock. We used a combination of methods (field surveys, interview surveys, and data from secondary sources) to examine the patterns and factors driving livestock depredation by free-ranging dogs, as well as economic losses to local communities in a Trans-Himalayan agro-pastoralist landscape in India. Our results show that livestock abundance was a better predictor of depredation in the villages than local dog abundance. Dogs mainly killed small-bodied livestock and sheep were the most selected prey. Dogs were responsible for the majority of livestock losses, with losses being comparable to that by snow leopards. This high level of conflict may disrupt community benefits from conservation programs and potentially undermine the conservation efforts in the region through a range of cascading effects.  相似文献   

14.
“控源-截污-资源化”模式处理面源污染   总被引:2,自引:0,他引:2  
针对农村面源污染的时空范围广,不确定性大,成分、过程复杂,难以控制的特点,同时考虑废物资源化的问题,提出了"控污-截污-资源化(再利用)"CIR模式,包括三方面:通过改变不良用水习惯及耕作方式等从源头上控制污染排放;利用植物缓冲带、自然塘、沟渠湿地和表面流湿地等达到截污的目的;将畜禽养殖废水及生活黑水集中处理,产生沼气,变废为宝,于湿地内种植经济类水生植物,兼性塘内水产养殖,最终实现废物资源化(再利用)。经过将近一年半的运行测试,测试结果表明,整个模式不仅除污效率高,而且可产生良好的经济效益。  相似文献   

15.
Nature conservation organisations increasingly turn to new digital technologies to help deliver conservation objectives. This has led to collaborative forms of working with academia to spearhead digital innovation. Through in-depth interviews with three UK research-council-funded case studies, we show that by working with academics conservation organisations can receive positive and negative impacts, some of which cut across their operations. Positive impacts include new ways of engaging with audiences, improved data workflows, financial benefits, capacity building and the necessary digital infrastructure to help them influence policy. Negative impacts include the time and resources required to learn new skills and sustain new technologies, managing different organisational objectives and shifts in working practices as a result of the new technologies. Most importantly, collaboration with academics was shown to bring the opportunity of a profound change in perspectives on technologies with benefits to the partner organisations and individuals therein.  相似文献   

16.
Recently, new approaches to wildlife management are being developed, such as coexistence management and convivial conservation. These approaches aim to shift management practices from mitigating human–wildlife conflicts towards cohabitation and explore mutual benefits. To align empirical research to these new approaches, we argue for the relevance of positive psychology theory to inspire and structure research into the benefits of human–wildlife interactions. Positive psychology suggests three pathways through which human–wildlife interactions may lead to happiness and well-being: pleasure, engagement, and meaning. Applying these pathways to human–wildlife research may (i) structure existing research into the benefits of human–wildlife interactions, (ii) disclose unidentified benefits of human–wildlife interactions, and (iii) unravel mechanisms which make experiencing and protecting wildlife worthwhile and rewarding. Also, we suggest a potential feedback loop between wildlife experiences, happiness and well-being, and pro-environmental behaviours. More in-depth research into these mechanisms may improve our understanding of attitudes towards conservation of wildlife and its habitat and may suggest strategies to strengthen stewardship actions and public support for conservation strategies. Together, these strands of research could initiate research into what could be called a “Positive Ecology”.  相似文献   

17.
When spatial fishing data is fed into systematic conservation planning processes the cost to a fishery could be ensured to be minimal in the zoning of marine protected areas. We used vessel monitoring system (VMS) data to map the distribution of prawn trawling and calculate fishing intensity for 1-ha grid cells, in the Kosterhavet National Park (Sweden). We then used the software Marxan to generate cost-efficient reserve networks that represented every biotope in the Park. We asked what were the potential gains and losses in terms of fishing effort and species conservation of different planning scenarios. Given a conservation target of 10 % representation of each biotope, the fishery need not lose more than 20 % of its fishing grounds to give way to cost-efficient conservation of benthic diversity. No additional reserved area was needed to achieve conservation targets while minimizing fishing costs. We discuss the benefits of using VMS data for conservation planning.  相似文献   

18.
A linear programming model is proposed to find the energy strategy for reducing carbon dioxide emission in Taiwan. Scenarios that include energy switching and energy conservation under different emission levels are considered, and the corresponding economic impacts are evaluated. Emissions from thirty-nine sectors are reduced by two major mechanisms. Energy switching is assumed to be induced by energy price change, whereas energy conservation is assumed only in the four most energy-intensive sectors. The results show the economic impact on gross domestic product under different energy scenarios. Appropriate energy strategies for carbon dioxide emission reduction could be implemented based on the scenario analysis.  相似文献   

19.
Novel urban ecosystems, biodiversity, and conservation   总被引:2,自引:0,他引:2  
With increasing urbanization the importance of cities for biodiversity conservation grows. This paper reviews the ways in which biodiversity is affected by urbanization and discusses the consequences of different conservation approaches. Cities can be richer in plant species, including in native species, than rural areas. Alien species can lead to both homogenization and differentiation among urban regions. Urban habitats can harbor self-sustaining populations of rare and endangered native species, but cannot replace the complete functionality of (semi-)natural remnants. While many conservation approaches tend to focus on such relict habitats and native species in urban settings, this paper argues for a paradigm shift towards considering the whole range of urban ecosystems. Although conservation attitudes may be challenged by the novelty of some urban ecosystems, which are often linked to high numbers of nonnative species, it is promising to consider their associated ecosystem services, social benefits, and possible contribution to biodiversity conservation.  相似文献   

20.
Statistical and spatial analyses of both historical time series and remotely sensed data show a link between the spatial distribution and growth of gold production across the Guiana Shield in northeast Amazonia. Results indicate that an exponential rise in production across an expanding area is primarily a delayed response to the 1971-1978 market flotation of international gold prices. The subsequent 10-fold (2-fold) average nominal (real) price increase has provided a compelling economic incentive to mass exploitation of lower-grade gold deposits. The ground-based and remotely sensed distributions of mining activity are strongly attached to these deposits that dominate the region's gold geology. The presence of these gold-bearing formations in conservation and sustainable timber zones has sparked social conflict and environmental degradation across the region. Left unmanaged, more than a quarter-million square-kilometer area of tropical forest zoned for protection and sustainable management could ultimately be compromised by the price-driven boom in gold mining through poorly integrated resource use planning, lack of reclamation effort, and control of illegal operations. Serious public health issues propagated through the unregulated mining environment further erode the financial benefits achieved through gold extraction. This study demonstrates in part how international economic policies successfully stabilizing more conspicuous centers of the global economy can have unintended but profound environmental and social impacts on remote commodity frontiers.  相似文献   

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