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461.
As human influences fragment native communities and ecosystems, remaining land must be better managed to conserve many elements
of biodiversity. Much of this land is privately held, yet traditional private land-use management practices often further
diminish biodiversity by promoting favored or edge-adapted species.
Today, private land stewards are increasingly aware of and concerned about biodiversity, but little guidance exists for them
to make land-use decisions incorporating principles and knowledge from conservation biology. Consequently, most management
strategies are highly subjective. This article addresses that problem by introducing current conservation wisdom to management
and use of private lands. The result is a model program for developing land management plans, with the goal of maintaining
viable populations and natural distributions of native species and communities from a landscape perspective.
The program establishes a protocol for classifying sites according to the importance of their species, communities, and other
elements to global and regional biodiversity. These site classifications are based on the management objectives necessary
to maintain important elements. Once managers classify a site, the program provides management standards, general stewardship
principles, examples of land management strategies, and basic monitoring and evaluation procedures. 相似文献
462.
Floodplain management programs have been adopted by more than 85% of local governments in the nation with designated flood hazard areas. Yet, there has been little evaluation of the influence of floodplain policies on private sector decisions. This article examines the degree to which riverine floodplain management affects purchase and mitigation decisions made by owners of developed floodplain property in ten selected cities in the United States. We find that the stringency of such policies does not lessen floodplain property buying because of the overriding importance of site amenity factors. Indeed, flood protection measures incorporated into development projects appear to add to the attractiveness of floodplain location by increasing the perceived safety from the hazard. Property owner responses to the flood hazard after occupancy involve political action more often than individual on-site mitigation. Floodplain programs only minimally encourage on-site mitigation by the owner because most owners have not experienced a flood and many are unaware of the flood threat. It is suggested that floodplain programs will be more effective in meeting their objectives if they are directed at intervention points earlier in the land conversion process. 相似文献
463.
Ariane de Bremond 《Ambio》2021,50(7):1299
This perspective recognizes the seminal Ambio articles of Sombroek et al. (1993), Turner et al. (1994) and Brussaard et al. (1997), identifying their individual and collective role in laying the ground work for a global change research agenda on land and its human use through increased understanding of terrestrial ecosystem dynamics and global change, and furthering nascent interdisciplinary efforts within the global change science community to better understand the ‘human driving forces’ of change. From these efforts, land system science, as a systemic science focused on complex socio-ecological interactions around land use and associated trade-offs and synergies, emerges as an ‘interdiscipline’ challenged to better understand land systems as the ‘meeting ground’ for multiple claims on land for biodiversity, carbon, livelihoods, food production among others, and support pathways to sustainability for people and nature. 相似文献
464.
465.
探讨许昌市地面沉降的原因及其对策 总被引:1,自引:0,他引:1
许昌市地表水资源严重短缺,为了供水的需要,该市掠夺性地开采地下水,造成地下水水位急骤下降,市区大面积地面沉降,已出现地裂现象.提出要合理地使用地下水资源、限制超量开采、开源节流,补充地下水源等措施,使地下水位逐渐回升,防止该市地面继续沉降而产生的不可挽回的后果. 相似文献
466.
本文在分析伊犁地区农业自然资源特点和合理用地结构的基础上,预测不同时期一定生产条件下,单位面积土地上粮食,油料肉类的生产潜力和不同生活水平下所承载的人口数量。 相似文献
467.
Tanya M. Howard 《Local Environment》2020,25(2):130-146
ABSTRACTIn 2014 an Australia public servant was killed in a confrontation over illegal land clearing. The perpetrator was a land holder with a history of non-compliance with environmental regulations and had been subject to a series of prosecutions. Political suggestions that the crime was somehow justified drew attention to the growing prevalence of law breaking linked to environmental law and policy in rural Australia. This paper investigated the social construction of both the crime and the community response through a qualitative media content analysis. Utilising the “Recipe for Criminalisation” framework developed by Amnesty International, the analysis identified a contest between media discourses of legitimacy in regards to the actions taken by the perpetrator, the public servant and ultimately, the regulatory framework itself. The analysis revealed that the link between media references to illegitimate legislation, excessive regulation, over-zealous compliance and strong social norms of rural independence and economic survival created a persuasive story of justified resistance to unwelcome environmental legislation in this case. Understanding how affected communities respond to instances of policy failure, civil and criminal law breaking and environmental compliance is a crucial factor in designing more legitimate and effective governance regimes. How media narratives are constructed, by whom and in whose interests remains an important analytic question for the study of resistance to environmental law and policy around the world. 相似文献
468.
469.
Êrika B. Fernandes Cruvinel Mercedes M. da C. BustamanteAlessandra R. Kozovits Richard G. Zepp 《Agriculture, ecosystems & environment》2011,144(1):29-40
In the last 40 years, a large area of savanna vegetation in Central Brazil (Cerrado) has been converted to agriculture, with intensive use of fertilizers, irrigation and management practices. Currently, the Cerrado is the main region for beef and grain production in Brazil. However, the consequences of these agricultural practices on NO, N2O and CO2 emissions from soil to atmosphere are still poorly investigated. The objectives of this study were to quantify soil emissions of NO-N, N2O-N and CO2-C in different no-till cultivation systems in comparison with native savanna vegetation. The agricultural areas included: (a) the maize and Brachiaria ruzizienses intercropping system followed by irrigated bean in rotation; (b) soybean followed by natural fallow; and (c) cotton planting over B. ruzizienses straw. The study was performed from August 2003 to October 2005 and fluxes were measured before and after planting, after fertilizations, during the growing season, before and after harvesting. NO-N fluxes in the soybean field were similar to those measured in the native vegetation. In the cornfield, higher NO-N fluxes were measured before planting than after planting and pulses were observed after broadcast fertilizations. During Brachiaria cultivation NO-N fluxes were lower than in native vegetation. In the irrigated area (bean cultivation), NO-N fluxes were also significantly higher after broadcast fertilizations. Most of the soil N2O-N fluxes measured under cultivated and native vegetation were very low (<0.6 ng N2O-N cm−2 h−1) except during bean cultivation when N2O-N fluxes increased after the first and second broadcast fertilization with irrigation and during nodule senescence in the soybean field. Soil respiration values from the soybean field were similar to those in native vegetation. The CO2-C fluxes during cultivation of maize and irrigated bean were twice as high as in the native vegetation. During bean cultivation with irrigation, an increase in CO2-C fluxes was observed after broadcast fertilization followed by a decrease after the harvest. Significantly lower soil C stocks (0-30 cm depth) were determined under no-tillage agricultural systems in comparison with the stocks under savanna vegetation. Fertilizer-induced emission factors of N oxides calculated from the data were lower than those indicated by the IPCC as default. 相似文献
470.