Managing and learning with multiple models: Objectives and optimization algorithms

The quality of environmental decisions should be gauged according to managers’ objectives. Management objectives generally seek to maximize quantifiable measures of system benefit, for instance population growth rate. Reaching these goals often requires a certain degree of learning about the system. Learning can occur by using management action in combination with a monitoring system. Furthermore, actions can be chosen strategically to obtain specific kinds of information. Formal decision making tools can choose actions to favor such learning in two ways: implicitly via the optimization algorithm that is used when there is a management objective (for instance, when using adaptive management), or explicitly by quantifying knowledge and using it as the fundamental project objective, an approach new to conservation.This paper outlines three conservation project objectives – a pure management objective, a pure learning objective, and an objective that is a weighted mixture of these two. We use eight optimization algorithms to choose actions that meet project objectives and illustrate them in a simulated conservation project. The algorithms provide a taxonomy of decision making tools in conservation management when there is uncertainty surrounding competing models of system function. The algorithms build upon each other such that their differences are highlighted and practitioners may see where their decision making tools can be improved.     

Uncertainty and adaptive management for biodiversity conservation

Adaptive management of natural resources is widely supported, but in biodiversity conservation there have been few practical applications of the approach in its entirety. Some of the contributions to this special publication examine progress in the implementation of adaptive approaches into conservation policy, while others explore novel theoretical and modeling approaches that seek to accommodate the complexities of real-world applications. Several of the papers address the treatment of uncertainty in adaptive management through innovative approaches to experimentation and monitoring, use and characterisation of expert knowledge and reconciliation of differences of opinion about parameters or systems. Drawing on these contributions, we discuss the major impediments to implementing adaptive management, why adaptive management has been slow to be implemented and how this can be redressed.     

Development options of natural habitats in a post‐mining landscape

Rehabilitation of the post‐mining landscape of Lower Lusatia (Brandenburg, Germany) represents a complex problem: 85 per cent of this area is currently being recultivated for forests or agriculture and 15 per cent is reserved for nature development. After mining, soil conditions are dry, acidic and nutrient poor. The ‘LENAB’ project aimed at conservation strategies and management options for natural habitats. Two competing basic motives of nature conservation on a small or medium scale were defined: (1) close‐to‐naturalness (allowing natural dynamics to take place without human interference) and (2) biodiversity (selective species and habitat protection). An overall strategy for sustainability of a cultural landscape can only be applied to the entire post‐mining landscape. The application of the two basic motives leads to different management options; this is illustrated by two important vegetation types. Copyright © 2000 John Wiley & Sons, Ltd.     

General management principles and a checklist of strategies to guide forest biodiversity conservation

Many indicators and criteria have been proposed to assess the sustainable management of forests but their scientific validity remains uncertain. Because the effects of forest disturbances (such as logging) are often specific to particular species, sites, landscapes, regions and forest types, management “shortcuts” such as indicator species, focal species and threshold levels of vegetation cover may be of limited generic value. We propose an alternative approach based on a set of five guiding principles for biodiversity conservation that are broadly applicable to any forested area: (1) the maintenance of connectivity; (2) the maintenance of landscape heterogeneity; (3) the maintenance of stand structural complexity; and (4) the maintenance of aquatic ecosystem integrity; (5) the use of natural disturbance regimes to guide human disturbance regimes.We present a checklist of measures for forest biodiversity conservation that reflects the multi-scaled nature of conservation approaches on forested land. At the regional scale, management should ensure the establishment of large ecological reserves. At the landscape scale, off-reserve conservation measures should include: (1) protected areas within production forests; (2) buffers for aquatic ecosystems; (3) appropriately designed and located road networks; (4) the careful spatial and temporal arrangement of harvest units; and (5) appropriate fire management practices. At the stand level, off-reserve conservation measures should include: (1) the retention of key elements of stand structural complexity (e.g., large living and dead trees with hollows, understorey thickets, and large fallen logs); (2) long rotation times (coupled with structural retention at harvest); (3) silvicultural systems alternative to traditional high impact ones (e.g., clearcutting in some forest types); and (4) appropriate fire management practices and practices for the management of other kinds of disturbances.Although the general ecological principles and associated checklist are intuitive, data to evaluate the effectiveness of many specific on-the-ground management actions are limited. Considerable effort is needed to adopt adaptive management “natural experiments” and monitoring to: (1) better identify the impacts of logging operations and other kinds of management activities on biodiversity, and; (2) quantify the effectiveness of impact mitigation strategies; and (3) identify ways to improve management practices.     

The utility of transient sensitivity for wildlife management and conservation: Bison as a case study

Developing effective management strategies is essential to conservation biology. Population models and sensitivity analyses on model parameters have provided a means to quantitatively compare different management strategies, allowing managers to objectively assess the resulting impacts. Inference from traditional sensitivity analyses (i.e., eigenvalue sensitivity methods) is only valid for a population at its stable age distribution, while more recent methods have relaxed this assumption and instead focused on transient population dynamics. However, very few case studies, especially in long-lived vertebrates where transient dynamics are potentially most relevant, have applied these transient sensitivity methods and compared them to eigenvalue sensitivity methods. We use bison (Bison bison) at Badlands National Park as a case study to demonstrate the benefits of transient methods in a practical management scenario involving culling strategies. Using an age and stage-structured population model that incorporates culling decisions, we find that culling strategies over short time-scales (e.g., 1–5 years) are driven largely by the standing population distribution. However, over longer time-scales (e.g., 25 years), culling strategies are governed by reproductive output. In addition, after 25 years, the strategies predicted by transient methods qualitatively coincide with those predicted by traditional eigenvalue sensitivity. Thus, transient sensitivity analyses provide managers with information over multiple time-scales in contrast to the long time-scales associated with eigenvalue sensitivity analyses. This flexibility is ideal for adaptive management schemes and allows managers to balance short-term goals with long-term viability.     

A critical assessment of adaptive ecosystem management in a large savanna protected area in South Africa

This paper uses five inter-related topics (the management of rivers, fire regimes, invasive alien species, rare antelope and elephants) to assess 15 years of adaptive management in the Kruger National Park (KNP), South Africa. The importance of adaptive planning (a process for developing achievable objectives, which is adaptive because objectives are revised as understanding grows), has been highlighted by this assessment, and the KNP’s track record of adaptive planning is better than that of adaptive management. Adaptive management has identified important issues with regard to biodiversity conservation, and resulted in a shift in management focus to these issues. Because the conservation outcomes of management shifts will only manifest themselves in the longer term, the relative success of adaptive management should be measured by the degree to which management has been refocused onto priority issues, and by the rate at which new understanding is generated. Some issues previously seen as important (fire, rare antelope), are now regarded as less so, while others remain important and difficult to solve, although there has been some progress (rivers, alien plants and elephants). It has also proved difficult to implement active adaptive management (large-scale, replicated trials using different approaches), because of local variation and logistical problems. Adaptive management will remain the approach of choice because there is some progress, and no known alternative to managing this complex ecosystem. It is simply not an option to return to the easily-understood “implementable” solutions (such as culling, regular prescribed burning, or artificial water provision) that demonstrably did not work.     

Conserving forest biodiversity across multiple land ownerships: Lessons from the Northwest Forest Plan and the Southeast Queensland regional forests agreement (Australia)

As the area of the world’s forests shrinks, the management of production forests is becoming increasingly paramount for biodiversity conservation. In the United States and Australia, public debate and controversy about the management of production forests during the later decades of the 20th century resulted in governments adopting sweeping top-down changes to forest policy, with regional forest plans a cornerstone of this process. This paper reviews the biodiversity conservation outcomes of two such processes, the Southeast Queensland Forests Agreement (Australia) and the Northwest Forest Plan (United States). Several key lessons are identified. First, these plans are significant steps forward in the struggle to conserve forest biodiversity while providing for production of timber. Second, expanding the conservation reserve system by itself does not necessarily ensure biodiversity conservation, especially if reserves are traded off for increased timber harvesting in forests outside of reserves or if certain important elements of biodiversity are not accounted for either by conservation forests or production forests. Third, reserves often need active management to restore diversity in previously-logged forests and reduce fuels that have accumulated as a result of fire exclusion. Fourth, the current plans fall short of the comprehensive whole-of-landscape, multiple-ownership approach needed to support long-term sustainable forestry and biodiversity conservation. Fifth, adaptive management was not adequately institutionalized and sometimes misapplied, although, in the case of the Pacific Northwest, a major regional monitoring strategy was developed and partially implemented. Finally, ecological science suffered in the collision with the socio-political decision-making process due to the limited scope that was left for testing and evaluating the new approaches to forest management. We conclude, based on the evaluation of the two regional plans, that regional biodiversity conservation goals may be better achieved by implementing sustainable forest management practices across all ownerships and involving all stakeholders and the broader community.     

The role of cost-effectiveness analysis in conservation decision-making

Strategies for biodiversity conservation require society to make choices between competing outcomes. However, these choices are complicated by an incomplete understanding of the ecological significance of different species and the lack of robust measures of conservation outcomes in relation to investments. Cost-effectiveness analysis (CEA) provides an objective assessment process that can help us to evaluate the effectiveness of different conservation programmes and adjust them in an adaptive manner to improve the chances of success. CEA and other objectively-constructed methods should form an important part of the evidence base for conservation decision-making and evaluation.     

生产建设项目水土保持分类与分类管理对策

[目的]系统总结生产建设项目水土流失特征,分析管理工作现状与存在问题,提出实行分类管理的具体意见。[方法]采用调查分析法,调查国家级、不同水土流失类型区的省级及其典型县生产建设项目水土保持管理的经验与成效,分析生产建设项目分类管理的实践经验。[结果]按照项目水土流失影响特征、影响程度以及项目所在地域地形特点和水土保持敏感程度,进行分类管理。[结论]根据分类结果,将水土保持方案编报划分为报告书、报告表和报告简表三类,在方案审批中的审查、审批、变更、公示环节,方案实施中的监督检查、水土保持监理、监测工作,项目竣工时的水土保持验收环节分别实行不同的管理程序并提出要求。     

Challenges and opportunities of genetic approaches to biological conservation

I discuss future challenges and opportunities in genetic approaches to biodiversity conservation. Resolving taxonomy uncertainties and identifying diverged evolutionary units within species are both bedevilled by a plethora of definitions: the challenge for the conservation community is to come to an agreed definition of species and for a unit within species for conservation purposes. For genetic management in the wild, the main challenge is to apply well-established genetic principles to management, especially of fragmented populations. Fears about outbreeding depression are preventing rational use of gene flow for genetic rescue; predicting the risk of outbreeding depression is the most important unmet scientific challenge in the field. The major challenge in genetic management of captive populations of threatened animal species is to institute explicit management to minimize genetic adaptation to captivity, so that reintroduction success is maximized. The development of low cost genome sequencing offers many research opportunities and challenges. For example, there are opportunities to identify genes involved in speciation and a major challenge is to devise molecular tests to predict reproductive isolation between populations. Genomics offers opportunities to provide higher precision estimate for many parameters of importance to conservation. A major challenge is to devise means to assess, on a genome-wide basis, genetic diversity that is important to adaptive evolution. There is a challenge to develop simple inexpensive means to monitor genetic diversity of species on a global scale. Many of the most important practical challenges concern application of current genetic knowledge to the management of threatened species.     

Conserving Africa’s rain forests: problems in protected areas and possible solutions

Problems and correlates of success in the conservation of Africa’s rain forests were evaluated for 16 protected areas in 11 countries, representing approximately half of all protected areas in this biome. Data were obtained from questionnaires, published and unpublished accounts, and direct observations. Despite numerous problems, all protected areas conserved indigenous rain forest biodiversity more effectively than did alternative land uses. More than half the protected areas suffered extensive ecological isolation. Effective management of protected areas was seriously compromised by inadequate funding and government support. Dense human populations, often resulting from immigration, constituted major threats to protected areas. Perceived conservation success was greatest for large protected areas surrounded by similar habitat with strong public support, effective law enforcement, low human population densities, and substantial support from international donors. Contrary to expectations, protected area success was not directly correlated with employment benefits for the neighboring community, conservation education, conservation clubs, or with the presence and extent of integrated conservation and development programs. Studies are needed to better understand what shapes positive pubic attitude towards protected areas because none of the conventional public outreach programs were correlated with public attitude. We also identify apparent deficiencies in foreign assistance to these protected areas. The single most important short-term strategy was considered to be the improvement of law enforcement effectiveness through greater technical and financial support. Nine medium-term strategies are identified, including provision of adequate and secure long-term funding, establishing research and monitoring programs, and developing more appropriate conservation and development programs. Long-term strategies deal with two ultimate causal factors, mainly attitudes and value systems, and stabilizing human populations. Future success of Africa’s protected areas is contingent upon long-term international assistance including contingencies mandating realistic performance standards.     

V. V. Dokuchaev and the present-day paradigm of nature management

The acceptance of the biospheric paradigm of nature management anticipated by V.V. Dokuchaev instead of the anthropocentric ideology suggests a solution of problems related to the ecologization of agriculture and its adaptive intensification under the conservation of soil ecological functions. The landscape-ecological principles of human economic activity proposed by Dokuchaev have developed into the modern methodology of agrolandscape design and adaptive-landscape farming.     

Do conservation managers use scientific evidence to support their decision-making?

Conservation involves making decisions on appropriate action from a wide range of options. For conservation to be effective, decision-makers need to know what actions do and do not work. Ideally, decisions should be based on effectiveness as demonstrated by scientific experiment or systematic review of evidence. Can decision-makers get this kind of information? We undertook a formal assessment of the extent to which scientific evidence is being used in conservation practice by conducting a survey of management plans and their compilers from major conservation organizations within the UK. Data collected suggest that the majority of conservation actions remain experience-based and rely heavily on traditional land management practices because, many management interventions remain unevaluated and, although some evidence exists, much is not readily accessible in a suitable form. We argue that nature conservation along with other fields of applied ecology, should exploit the concept of evidence-based practice developed and used in medicine and public health that aims to provide the best available evidence to the decision-maker(s) on the likely outcomes of alternative actions. Through critical evaluation, we present the challenges and benefits of adopting evidence based practice from the decision-makers point of view and identify the process to be followed to make it work.     

Assessing the potential of changing land use for reducing soil erosion and sediment yield of catchments: a case study in the highlands of northern Ethiopia

Reservoir sedimentation is the most serious threat for water harvesting schemes and hydroelectric power dams in Ethiopia. Designing watershed conservation strategies and management is crucial to reduce the rate of sedimentation. Because different landscape types have varying potentials for enhancing erosion processes, site‐ and process‐specific conservation measures are needed to target an appropriate intervention to the most needed locations. In this study, a GIS‐based distributed soil erosion/deposition model was used to simulate the potential of land‐use and cover (LUC) changes and conservation measures for reducing water induced soil erosion and potential sediment yield for two catchments in northern Ethiopia. LUC change and conservation measures targeted gully and stream buffers, protection of steep slopes and protection of areas with soil loss greater than a given threshold. The results show that land management measures targeted at hot‐spot areas of erosion and gully formation could reduce potential annual sediment yield from catchments by approximately 60% compared with the current losses. The study demonstrates the potential of a GIS‐based LUC‐redesign approach as a tool for optimizing land‐use and management strategies to reduce run‐off and erosion rates in the highlands of northern Ethiopia.     

陕西省西安市水土保持区划研究

[目的]分析总结2014—2015年西安市水土保持区划工作,为区域水土流失综合治理提供依据和方向。[方法]通过对西安市的实地调查及相关资料的收集,利用遥感和GIS技术进行数据分析和处理,明确该市水土流失现状及特点,在一定区划原则基础上,进行指标的选择和分析。[结果]将西安市划分为6个水土保持区,提出各分区的水土保持治理方向,为城市建设及社会经济发展提供重要依据。[结论]西安市开展水土保持应在预防为主,保护优先的前提下,依据水土保持分区,以城区为核心,以河流和道路为廊道,对各斑块实施水土流失与环境的综合治理。     

淮河流域生态脆弱区水土保持管理机制的探索与实践

生态系统的退化给人类生存和发展带来越来越不利的影响,为了促进退化生态系统的修复,从管理机制探索与实践方面进行了深入的研究。文章在分析淮河流域水土保持工作中存在的主要管理问题的基础上,研究建立了水土保持管理模式和管理流程,并依托水土保持重点工程建设,探索了生态脆弱区以预防监督为主要手段,以合同管理为纽带,以规范项目管理和目标管理、联户合作式经营管理、大户牵头股份合作式经营管理、专业承包式经营管理、产权流转式经营管理、"公司+农户"式经营管理为主要内容的水土保持管理机制。     

Dynamic economic management of soil erosion,nutrient depletion,and productivity in the north central USA

Physical scientists have presented a wealth of evidence regarding the effects of cropland soil degradation. Because soil degradation has both on‐site and off‐site effects, public policies have often tried to increase rates of conservation over privately optimal rates. Where private incentives leave off and public incentives start up is somewhat controversial, however. Physical evidence, while necessary, is not sufficient to predict conservation actions by farmers in response to the threat of degradation. This paper provides a partial explanation for why farmers may adopt differing conservation strategies, even though they share similar preferences. A model is constructed that divides soil degradation into reversible and irreversible components. We portray nutrient depletion as a reversible facet of soil degradation and soil profile depth depletion as an irreversible facet of soil degradation. Predictions of optimal management response to soil degradation are accomplished using a closed‐loop model of fertilizer applications and residue management to control future stocks of soil nutrients and soil profile depth. Our model is applied to degradation data from nine soils in the north central United States. Three principal findings result: First, due to differences in initial soil properties, susceptibility to degradation, sensitivity of yield to soil depth, and yield response to alternative management practices, dynamically optimal economic strategies cannot be inferred directly from physical results but are inferred from the associated economic implications. Second, optimal residue management is more variable with respect to soil type than to the erosion phase of the soil, implying that substantial gains to targeting are possible. Third, nutrient depletion is a more compelling motivator for adopting residue management than soil profile depth depletion. This implies that motivating residue management requires programs that pay even greater attention to reversible degradation, and therefore the overall farm management implications, rather than strictly to protect topsoil from irreversible degradation. Copyright © 2001 John Wiley & Sons, Ltd.     

关于江西省水土保持监测数据库管理的探讨

随着江西省水土保持监测工作的开展,水土保持监测资料已经有了相当积累,而数据的综合、分析和管理等则日益暴露出问题。就江西省水土保持监测数据库的管理,对水土保持监测数据库的设计原则、数据库规范化和标准化以及数据库安全等方面的问题进行了探讨。     

森林可持续经营标准与指标中水土保持指标的研究

水土保持指标是森林可持续经营标准与指标中的一项重要内容。介绍了森林可持续经营标准与指标的概况,水土保持与森林可持续经营的关系,国际和中国水土保持指标的研究现状,应用中存在的问题,为森林可持续经营实践和水土保持指标的完善提供借鉴。     

Conservation in the face of climate change: The roles of alternative models, monitoring, and adaptation in confronting and reducing uncertainty

The broad physical and biological principles behind climate change and its potential large scale ecological impacts on biota are fairly well understood, although likely responses of biotic communities at fine spatio-temporal scales are not, limiting the ability of conservation programs to respond effectively to climate change outside the range of human experience. Much of the climate debate has focused on attempts to resolve key uncertainties in a hypothesis-testing framework. However, conservation decisions cannot await resolution of these scientific issues and instead must proceed in the face of uncertainty. We suggest that conservation should precede in an adaptive management framework, in which decisions are guided by predictions under multiple, plausible hypotheses about climate impacts. Under this plan, monitoring is used to evaluate the response of the system to climate drivers, and management actions (perhaps experimental) are used to confront testable predictions with data, in turn providing feedback for future decision making. We illustrate these principles with the problem of mitigating the effects of climate change on terrestrial bird communities in the southern Appalachian Mountains, USA.