دانلود رایگان مقاله انگلیسی مدیریت ریسک های آب و هوایی در مراتع پرورش احشام با اطلاعات محدودی درباره خشکسالی - الزویر 2018

ABSTRACT

Ranching involves complex decision-making and risk management in the face of uncertainty about climate conditions. The profitability and sustainability of ranching depend heavily on sufficient and timely rainfall for rangeland forage production. As a result, ranchers may either adopt conservative long-term stocking strategies as a hedge against drought or practice a more dynamic approach in which they vary stocking rates and supplemental feed in response to drought. Yet, some strategies require more information about climate risks than is often available to ranchers. We review the literature to draw out the drought management options as well as the tools and products for drought monitoring and early warning that are available to ranchers. We find that a large gap remains between the information needs of ranchers seeking to adapt dynamically to drought and the information that is available. Moreover, even when actionable information is available, it is unclear whether ranchers are optimally incorporating that information into their risk management decisions. Further research is needed to understand how to package existing information into risk management decision tools in a way that addresses cognitive and operational barriers to support timely decisions that will reduce the impact of drought on profits and the long-term sustainability of rangelands. Due to the multi-faceted nature of climate risk management in ranching, further study of ranching behavior and decisions has the potential to bring new insights into climate risk management and decision and risk theory far beyond the field of ranching and agriculture.

5. Conclusions

Ranching is a dynamic socio-ecological system that must adapt to climate variability. Drought, especially if widespread, sets off a chain of ecological and economic effects within the system. Ranchers handle these climate risks in several ways. They diversify their operations, purchase insurance, and make short-term drought adaptation investments like buying extra feed or seeking additional pasturage. Over the long term they may stock conservatively, so there is sufficient forage for the herd even when rainfall drops, or they can stock at higher rates but be ready to adapt quickly to periods of drought by reducing forage demand (e.g., by destocking) or increasing forage supply (e.g., by buying supplemental feed). The conservative stocking strategy may be optimal on arid ranges (Thomas et al., 2015) and when information about drought is either not available or costly to obtain. Full carrying capacity stocking with agile adaptation may be optimal if climate information is readily available and easily incorporated into ranchers’ production strategies.

The key climate risk management challenge in ranching is making timely decisions while a slow-onset drought unfolds. To meet this challenge, ranchers need accurate assessments of drought conditions as they develop. In reviewing ranching decision structures and the current availability of drought information necessary to make adaptation investments by crucial decision points in the season, we conclude that drought forecasts, due to their limited skill (Hoerling et al., 2012), are not as useful to ranchers as highly accurate information about current drought conditions. Because drought adaptation investments are often irreversible, ranchers are hesitant to deviate from their normal practices based on information that is highly unreliable. Compared to low-skill forecasts of future conditions, a precise understanding of the current state of drought may be far more valuable. Ranchers already rely on the US Drought Monitor that gives a coarse assessment of drought conditions across the U.S. However, new measures of soil moisture like the Standardized Soil Moisture Index (SSI), the Soil Moisture Active Passive (SMAP) satellite, and the Vegetation Drought Response Index (VegDRI), as well as the Evaporative Demand Drought Index (EDDI) can provide clear information about current conditions on their ranches that serve as leading indicators for drought. While ranchers are especially interested in drought conditions on their ranches, they also can use information on drought conditions in other regions so that they can judge how other ranchers and thus cattle markets will respond.