Efficient versus Sustainable Livestock Grazing in the Sahel

To date, there is no consensus on optimal stocking rates in the semi‐arid Sahel. We develop a model for livestock management based on a detailed analysis of ecosystem dynamics, and we apply it to calculate optimal and sustainable livestock stocking rates in a Sahelian rangeland. The general model accounts for stochastic rainfall and the long‐term impact of grazing on rangeland productivity. For the case study area, the model shows that the optimal stocking rate is higher than the sustainable stocking rate. Hence, with current prices, it is optimal for the pastoralist society to deplete their resource base. In our case study, we also find that the current stocking rate exceeds the optimal stocking rate, which adds to soil depletion.     

Economic drought management index to evaluate water institutions’ performance under uncertainty*

Reservoir management and intertemporal water allocation are critical issues in semiarid regions where agriculture has to confront highly variable rainfall patterns. In this paper, we derive and propose an economic drought management index (EDMI) to evaluate water institutions’ performance to cope with drought risk. The EDMI is based on the optimal conditions of a stochastic dynamic optimisation problem that characterises reservoir management. The index's main advantages are its ease of interpretation and breadth of scope, as it incorporates information on hydrological processes, structural constraints, water institutions’ rules, and the economic benefits of water use. An empirical application is developed to assess the institutional rules governing water allocation in two different supply systems in Andalusia (southern Spain).     

Current Challenges of Laws for Preservation of Forest and Rangeland,Iran

In some cases, law acts and regulations problems and shortcomings have been considered as a factor in the forests and rangelands grabbing in Iran. Therefore, it was necessary to analyze this problem in a scientific framework. These questions were raised which of the forest and rangeland related acts and regulations are in shortcoming and problem? And which acts and regulations of other sectors conflict with the protection of these resources? To answer these questions, a research study was conducted using the Delphi method, which is based on a survey of experts. According to the results of the research, the 19 acts and regulations on the illegal acquisition and grabbing of forests and rangelands have problems and shortcomings. "The Organization, Duties, and Selection of Islamic Councils of the Country and the Selection of Mayors" act of 1996 was recognized as the most problematic law act in the field of forest and rangeland conservation. Some reasons for the problems of acts and regulations were mentioned as the ignorance of natural resource offices in some of the lands allocations, disrupting the national status of the forest and rangeland, the non-deterioration of the penalties of some of the acts due to the low level of penalties, the unfair allocation of forest and rangeland for other landuses, the permission to the illegal constructions in the forests and rangelands, allowing national lands free allocation for government debt relief, and the establishing conditions that facilitate the allocation of forest and rangeland for other uses. As a result, if related laws were not properly approved, they would also cause degradation of forests and rangelands. A periodic review of the efficiency of forest and rangeland laws is recommended to preserve these resources at the national level.     

Rainfall or price variability: what determines rangeland management decisions? A simulation-optimization approach to South African savannas

Savannas cover the greater part of Africa and Australia and almost half of South America and contribute to the livelihoods of more than 350 million people. With the intensification of land use during the second half of the 20th century, savannas have become increasingly degraded through bush encroachment as a consequence of increased grazing pressure. Research on rangeland dynamics, however, provides contradicting answers with regard to the causes and possible remedies of bush encroachment. In this article we present results from an application of a simulation-optimization model to the case of extensive rangeland management in South Africa. Our model differs from previous approaches in that it explicitly accounts for the influence of stochastic prices and rainfall on economically optimal management decisions. By showing the implications of neglecting price variation and stochasticity in rangeland models we provide new insights with regard to the determinants of bush encroachment and rangeland managers' economic return. We demonstrate that, in the case of South Africa, optimal rangeland management is likely to lead to bush encroachment that eventually makes livestock holding unprofitable. Yet, we identify the costs of fire management to be a limiting factor for managers to counteract bush encroachment and explore the impact of policy measures to reduce fire control costs on the ecological and economic sustainability of livestock holding.     

Optimal pest control in greenhouse production of ornamental crops

In this study, we develop a conceptual bioeconomic model of floriculture production with aesthetic benefits, wherein optimal decision rules depend on an intertemporal economic objective to maximize profits subject to economic and biological processes. Necessary conditions of the model identify optimal trajectories (e.g., simultaneous, single, or cycling controls) that define decision rules and economic thresholds for profit maximizing growers producing crops with aesthetic attributes. The necessary conditions also highlight intertemporal trade‐offs between aesthetic benefits and expected future net benefits of arthropod stocks, which have important policy implications. The model is applied to the greenhouse production system of ivy geranium.     

Market-based grazing land transfers and customary institutions in the management of rangelands: Two case studies on the Qinghai-Tibetan Plateau

Beginning in the early 1990’s, grazing lands once held in common were contracted to individual households in the rangeland regions of China. The resulting fragmentation of rangelands has led to ecological and social problems. As China seeks to address intractable poverty and rangeland degradation, attention has turned to rental, or transfer, of contracted grazing land as a market-based approach to re-aggregating grazing land into larger units that support economies of scale. However, given that many pastoral regions still maintain community customary institutions, what the relationship between market mechanisms and local customary institutions should be in rangeland management needs further analysis. This paper applies comparative case studies of two types of relationships between market mechanisms and customary institutions: (1) market mechanisms that replace customary institutions in the case of Axi village, and (2) market mechanisms that are embedded within customary institutions in Xiareer village. This allows contrast of the impacts of differing approaches on livelihoods, livestock production, and wealth differentiation among pastoral households. We found that there is a higher level of livestock mortality, lower livestock productivity, and higher livestock production cost in Axi Village compared to Xiareer Village. In addition, household asset levels are higher and there is less income differentiation in Xiareer Village. It is concluded that embedding market mechanisms within customary institutions has had notable benefits for the herders of Xiareer Village, because it is a better fit to the coupled pastoral social-ecological system. Based on these findings, we argue that in pastoral communities where the rangeland transfer system for contracted grazing land has not yet been implemented, it is critical to reconsider China’s current policy approach to pay greater attention to the innovative management systems being developed in local regions. Instead of considering market-based approaches as oppositional to traditional institutions, options that derive from the interaction of market-based and customary institutions should be considered.     

Fungicide resistance and misinformation: A game theoretic approach

Fungicide resistance is a serious problem for agriculture today. This analysis provides additional insight into the strategic behavior of farmers when their fungicide use generates a negative intertemporal production externality in the form of fungicide resistance. We find that when farmers encounter this type of externality, they choose fungicide levels that exacerbate fungicide resistance. We examine a compensation mechanism in which a farmer reduces fungicide use in exchange for a transfer. This mechanism reduces fungicide use; however, misinformation about the severity of fungicide resistance generates distortions. We find that one-sided misinformation could lead a farmer to choose socially optimal fungicide levels, which makes the compensation mechanism less necessary. In addition, we show that when both farmers are misinformed, the mechanism could lead farmers to choose fungicide levels below the socially optimal level depending on their pessimistic beliefs about the severity of fungicide resistance.     

Short-run Dynamics of Machinery Demand in Canadian Agriculture

Based on the hypothesis of intertemporal cost minimization, this paper develops an error correction model to explain short-run dynamics of machinery demand in aggregate Canadian agricultural production. The estimated model is subjected to a rigorous sequence of hypothesis tests to check for its statistical validity. In addition, various versions of the model that are nested within the most general model are also tested. Structural parameters of the intertemporal cost minimization problem are recovered from the parameter estimates.     

Land use optimization in watershed scale

Managing a watershed for satisfying the inhabitant's demand is a difficult task if one has to maintain a reasonable balance between usually conflicting environmental flows and demands. The solution to these complex issues requires the use of mathematical techniques to take into account conflicting objectives. Many optimization models exist for general management systems but there is a knowledge gap in linking practical problems with the optimum use of all land resources under conflicting demands in a watershed. In the present study, an optimization problem has been formulated for the Brimvand watershed, Iran, comprising ca. 9572 ha to find out the most suitable land allocation to different land uses, viz. orchard, irrigated farming, dry farming and rangeland targeting soil erosion minimization and benefit maximization.     

Cattle and Wildlife Competition for Forage: Budget Versus Bioeconomic Analyses of Public Range Improvements in British Columbia

We analyze the gains of public investments in range productivity when cattle compete for forage with wildlife herbivores. Ignoring extra-market values by applying conventional budget analyses leads to higher cattle stocking rates and lower overall social benefits of public range improvements. This is demonstrated numerically for public forage in British Columbia, where privately profitable cattle stocking rates on newly seeded range exceed those that are socially optimal, perhaps by as much as double depending on the assumptions one makes about marginal preservation benefits. This highlights the importance of applying dynamic optimization, bioeconomic models to analyze investments in public range.
Les auteurs analysent quel gain on tire des sommes publiques investies dans la productivité des grands parcours quand les bovins et les herbivores sauvages se livrent concurrence pour les fourrages. Ne pas tenir compte des valeurs extérieures au marché en recourant à des analyses budgétaires ordinaires entraîne une hausse du taux de chargement et une réduction des avantages sociaux globaux issus de la bonification des grands parcours. Il est possible d'en faire la preuve numérique avec les pâturages publics de la Colombie-Britannique, où les parcours nouvellement ensemencés supportent une population de bovins lucrative pour l'éleveur mais supérieure au taux de chargement optimal socialement, parfois même du double, selon les hypothèses qu'on formule sur les avantages d'une préservation marginale. l'étude souligne bien qu'il est important de recourir à une optimisation dynamique, soit d'utiliser les modèles bio-économiques pour analyser les sommes investies dans l'amélioration des pâturages publics.     

生态产业化与退耕还林还草

退耕还林还草是我国生态屏障建设的重要内容之一,但面临诸多问题,其中最关键的就是未能处理好林草植被建设中生态与经济的关系。退耕还林还草中,政府与农民之间不是监管的关系,而是服务与被服务的关系,通过生态产业化,将林草生态链转化为产业链和就业链,则退耕还林还草所遇到的一系列问题就能迎刃而解。     

An economic approach to soil fertility management for wheat production in north-eastern Australia

Soil fertility decline and soil management for crop production are important economic issues for grain growers in north-eastern Australia. In that region, there is evidence of soil fertility decline which is attributed to past crop management practices. The questions addressed in this article are first, whether components of soil fertility can be improved by better management and second, by how much soil fertility would change. Soil fertility for crop production is considered in terms of soil organic carbon and nitrogen. A stochastic dynamic economic analysis of soil fertility management for wheat production is presented. A sequential analysis of first deriving the optimal nitrogen stock and application rates is followed by an assessment of tillage, stubble, and fertilizer strategies to obtain an optimal level of soil organic carbon. The recommended management practices are consistent with emerging management trends in the region. The derivation of optimal levels of soil fertility for agricultural purposes has other policy implications, which we discuss.     

Dynamic Random Utility Modeling: A Monte Carlo Analysis

Applied studies of commercial fishing have largely ignored the intertemporal aspects of repeated site choices. For many fisheries, fishermen might choose a dynamically optimal cruise trajectory rather than myopic day-to-day strategies and a model that ignores these considerations will likely lead to biased parameter estimates and poor policy guidance. A dynamic random utility model is developed that utilizes the same information as static site-choice models but is entrenched in the principles of dynamic optimization. Using Monte Carlo analysis, we evaluate the performance of this estimator as compared to the static model for a variety of simulated fishery types.     

Incentivizing sustainable rangeland practices and policies in Colombia’s Orinoco region

Livestock grazing, along with agriculture, are key drivers of deforestation and land degradation that subsequently affect ecosystem service provision in the tropics. Although environmental and agricultural policies may curtail these negative effects, information is needed on how specific programs and instruments could be used to incentivize ranchers into adopting rangeland practices to achieve land conservation. We examine what encourages livestock ranchers to adopt more sustainable rangeland practices with various technical and conservation attributes in Colombia’s Orinoco region. First, we analyze a management alternative based on an improved pasture (IP) approach traditionally used in tropical South America, and another practice that promotes silvopastoral systems (SP) that better sustain the long term provision of ecosystem services. Second, we assess the influence that technical assistance and conservation payment instruments can have on the adoption of the IP or SP programs. Using expert-based elicitation, questionnaires, choice experiments, and econometrics, we found that when either SP or IP management alternatives include a complete technical assistance program (CTAP), emphasizing forage or cattle production, the propensity to adopt the conservation focused SP alternative significantly increases. The SP alternative with CTAP for cattle production was valued by ranchers at $290 ha/year and the CTAP prioritizing forage production was valued at $233 per ha/year. Nonetheless, a basic technical assistance program for cattle production using the IP alternative was valued at $128, but when including the CTAP, the value increased to $262. Adopting conservation practices in the form of compensation payments for not grazing portions of their land in the SP was valued by ranchers at an average of $8 and $10 in the IP. Our findings show that decisions to adopt conservation oriented rangeland practices and policies are not strictly based on monetary payments for ecosystem services alone, but also on technical support.     

RISK,UTILITY AND STOCKING RATE*

A simple utility-based model of risky wool production is presented. Evaluation of the model indicates the effect on optimal stocking rate of changes in the degree of risk aversion, farm area, variable cost, fixed cost, wool cut, wool price, variance of wool price, climatic variability and tax rate. It is shown that the utility hypothesis implies a lower optimal stocking rate than does expected profit maximization and hence implies a discrepancy between private and public optimal resource use which it is suggested, might be mitigated by a progressive bounty on wool production.     

土地流转背景下农户经营规模与土地生产率关系再审视——来自固定粮农和地块的证据

农户经营规模和土地生产率关系是发展经济学领域的经典议题之一。本文在土地流转加速发展的背景下讨论了我国农户经营规模扩大对土地生产率的影响以及测量两者之间关系面临的种种干扰。除了农户规模本身的作用外,理论和实证检验均表明存在土地流转市场时不同规模农户在土地生产率上的差异还可能源于农户和土地的异质性,譬如土地更多流向经营能力强的农户、流转多劣地等等。基于固定农户的固定地块数据可以有效控制异质性的实证策略,本文利用4个省两期跟踪调查数据对两者关系进行了再检验。研究发现,来自固定农户固定地块的证据表明农户土地经营规模扩大并不会影响粮食单产,而不控制固定地块时往往会得到两者负相关的伪结论,并且仅控制固定农户时上述伪结论更为明显。这一结果意味着不必担心规模经营会威胁粮食供给。     

Locating the adverse effects of rangeland enclosure among herders in eastern Ethiopia

This paper examines the effects of rangeland enclosure on herders’ livelihoods and property rights. The analysis is based on the household survey and focus group discussions among pastoral and agropastoral households (from three administrative districts in eastern Ethiopia) who have practiced enclosure and who have been affected by practices of others. Such an examination helps anticipate whether enclosure practice assists in attaining income security and ensuring household welfare by supporting livestock development. Results have shown that expansion of enclosure leads to the emergence of incompatible demands (conflict of interest) over the resource and unstable property rights to the grazing commons. Though private benefits from enclosure produce an incentive for households to practice it, its expansion does not generally increase the welfare of (agro-) pastoral community in the longer-term. Hence, land use policies that favor private use of the rangeland, using land enclosure as an entry point, can potentially harm pastoral livelihoods rather than supporting sustainable pastoral development.     

Empirical investigation of investment behaviour in Australia's pastoral region*

Optimal intertemporal investment behaviour of Australian pastoralists is modelled using panel data for the period 1979–1993. Results indicate that quasi‐fixity of inputs of labour, capital, sheep numbers and cattle numbers is characteristic of production in the pastoral region. It takes about two years for labour, four years for capital and a little over two years for both sheep numbers and cattle numbers to adjust towards long‐run optimal levels. Results also indicate that, after accounting for adjustment costs, own‐price product supply and input demand responses are inelastic in both the short and long run.     

A factor-income approach to estimating grassland protection subsidy payments to livestock herders in Inner Mongolia,China

This paper contributes to the growing literature on land use policies designed to prevent livestock overgrazing. It offers a straightforward factor-income approach to calculating payments for ecosystem services (PES) to livestock producers who reduce or suspend grazing for the purpose of grassland restoration. Our approach requires only cross-sectional farm-level accounting data and is thus feasible where policies have either not yet been applied or specialized data is sparse, as is common in many developing regions. We apply and validate this approach with empirical analysis of sheep and goat herders in the Ulanqab prefecture in Inner Mongolia, China where herders currently receive payments in exchange for reduced grazing intensity on vulnerable land. However, observed stocking rates are still commonly higher than recommended. Our results suggest payments are currently insufficient to offset the financial loss incurred by herders who reduce their grazing intensity, a finding consistent with previous studies. Using an approach we refer to as the factor-income method, we estimate and validate new levels of recommended payments. This demonstrates how future payments could be tailored to meet the financial needs of individual herding communities using basic farm-level data.     

Using participatory mapping and a participatory geographic information system in pastoral land use investigation: Impacts of rangeland policy in Botswana

Since the 1980s, the spatial extent of communal grazing lands in Botswana has been diminishing due to rangeland privatisation and fencing associated with animal health policies. Spatial comparisons of pastoral land use transformations are particularly important where accessibility to grazing and water resources remains at the core of sustainable pastoralism policies. Achieving success in pastoral development research requires a sound understanding of traditional pastoralists’ information systems, including the nature of local spatial knowledge. This study explores local spatial knowledge through participatory mapping and a Participatory Geographic Information System to understand and analyse pastoralists’ grazing patterns, spatial mobility and the impacts of subdivisions and privatisation policies in Botswana’s Ngamiland rangelands. The study uses focus group discussions, historical analysis through key informant interviews, and participatory mapping exercises along with community guided transect walks. The resulting maps provide insights into the traditional tenure patterns of land use and the impacts of rangeland policy on traditional livestock spatial mobility and access to grazing lands. Privatisation and rangeland enclosures have resulted in the restricted movement of livestock and overstocking of floodplains and riparian rangelands, with some natural water pans becoming inaccessible to local communities. We conclude that the integration of local spatial knowledge can be used to foster better articulation and understanding of pastoralists’ tenures, which are often lacking in communal land administration systems. Such integrated analysis can contribute to sustainable pastoral land management policy toolkits in semi-arid rangeland environments and enable better land tenure and management decision making for sustainable land management.