Intervene or wait? Modelling the timing of intervention in conservation conflicts adaptive management under uncertainty

The timing of biodiversity managers’ interventions can be critical to the success of conservation, especially in situations of conflict between conservation objectives and human livelihood, i.e., conservation conflicts. Given the uncertainty associated with complex social-ecological systems and the potentially irreversible consequences of delayed action for biodiversity and livelihoods, managers tend to simply intervene as soon as possible by precaution. However, refraining from intervening when the situation allows it can be beneficial, notably by saving critical management resources. Here, we introduce a strategy for managers to decide, based on monitoring, whether intervention is required or if waiting is possible. This study evaluates the performance of this waiting strategy compared to a strategy of unconditional intervention at every opportunity. We built an individual-based model of conservation conflict between a manager aiming to conserve an animal population and farmers aiming to maximize yield by protecting their crop from wildlife damage. We then simulated a budget-constrained adaptive management over time applying each strategy, while accounting for uncertainty around population dynamics and around decision-making of managers and farmers. Our results showed that when the decision for the manager to intervene was based on a prediction of population size trajectory, the waiting strategy performed at least as well as unconditional intervention while also allowing managers to save resources by avoiding unnecessary interventions. Under difficult budgetary constraints on managers, this waiting strategy ensured as high yields as unconditional intervention while significantly improving conservation outcomes by compensating managers’ lack of resources with the benefits accrued over waiting periods. This suggests that waiting strategies are worth considering in conservation conflicts, as they can facilitate equitable management with a more efficient use of management resources, which are often limiting in biodiversity conservation.

Delayed Action Micro-Emulsion Breaker and Its Applications to Improved Completions Operations – An NNPC/FEPDC JV Approach During Completions Operations

In horizontal open hole wells, the formation of filter cake while drilling the open hole section of the well is desirable. This filter cake serves the purpose of forming a semi-impervious layer around the reservoir drain-hole. This layer helps reduce losses considering the overbalance required for well control during drilling. It also serves as an additional structural support to keep the open hole stable when the drilling bottom hole assembly (BHA) is pulled out of hole and the screens and lower completions accessories are being run in hole. However, when thewell is put into production, the filter cake becomes a contributor to skin and poor reservoir productivity. It is therefore required to get rid of the filter cake after running the screens and the lower completion. Having procured and prepared the sand screens for deployment after drilling the open hole section, it is important that they are run to the bottom successfully with minimal damage and plugging. Usually, the open hole section of the horizontal well is drilled with specially formulated drill-in-fluids (DIF). Since this section is drilled in over balanced mode, the exerted pressure keeps the hole open so that the sand screen can be run successfully. The DIF replaces the drilling mud used to drill the earlier hole section(s) but in addition to providing well control via overbalance and transporting cuttings from the hole to surface, it also minimizes invasion damage to the reservoir pay zone. A commonly used weighing material when densities up to 11.5ppg are required for well control is calcium carbonate (CaCO3). When densities above 11.5ppg are required (for deeper, abnormally pressured reservoirs), it becomes necessary to weight up the mud with a heavier material, usually barite + CaCO3. During the drilling process, this overbalance pressure exerted on the reservoir forces the CaCO3 out of the DIF solution and it forms a semi-impervious filter cake on the sand face of the reservoir. This desirable filter cake helps minimize excessive fluid losses into the reservoir hence limiting invasion and damage. It also contributes to the structural integrity of the open hole, keeping it stable prior to running of the screens. Depending on the weighting material used in the drilling of the reservoir drain-hole, the micro-emulsion breaker (MEB) can be designed to break down the filter cake and any undisolvedparticulates can be mobilized and water-wetted and can be then flowed during production or injection. The challenge is that depending on the lower completion configuration, it may take some time to get the wash pipe and work string out of the lower completion and close the formation isolation device. In some cases, it is possible for the formation isolation device to fail. If the Micro-emulsion Blend (MEB) is quick acting, any of these scenarios can lead to uncontrollable losses and serious difficulties in continuing the completion operation. This elucidates the need for a delayed acting MEB treatment. Lab tests and analysis involving the exact DIF /filter cake and various compositions of the MEB at downhole conditions to arrive at the required delay in action. It is critical to ensure that the delayed action does not result in reduced efficacy of the treatment. Hence, the MEB is not diluted for slow action but rather it is engineered combinatorially with a retarder and downhole mild acid generating microemulsion chemistry that gradually generates the necessary mild acid that will slowly dissolve the bridging materials (eg. calcium carbonate) in the mud withtime and allows the full strength of the MEB to take effect after the stipulated delay period. This paper will focus on the lab analysis and iterations to arrive at an optimal MEB blend.

‘Environmental Impact Assessment’ in Drylands: Late Knowledge Penetration or a Deliberate Ignorance for Megaprojects?

Despite the paramount role of drylands in supporting people’s livelihoods and rendering ecosystem services, legislation on Environmental Impact Assessment has been introduced belatedly after several decades. By exemplifying Iran, the author proposes two main reasons for such a delayed action. First, drylands are misleadingly considered as barren lands where biodiversity is relatively low. In one classification, deserts are even categorized along with rocks. Second, the author emphasizes that drylands have been subjected to unprecedented changes due to the expansion of infrastructure and urbanization that started in the 1970s. These growing pressures have been beyond the ecological resilience of drylands and have not been monitored, assessed, and modified correctly. Further scrutiny regarding EIA undertakings in drylands and the way they can be improved is now needed.

Synovitis in osteoarthritis: the current state of the problem

The article presents current data on synovitis (inflammation of the synovial membrane), which is often the only clinical manifestation of osteoarthritis (OA), and considered to be one of the risk factors for the OA development. Synovitis severity correlates with the severity of OA symptoms. The assessment of the prevalence of synovitis presents significant difficulties and depends on the nature and severity of the disease, the cohort in question, diagnostic method, and therapy. The classification based on etiological, clinical and histological characteristics of synovitis is presented. Examination of synovial tissue characteristics and its changes during inflammatory response can significantly expand the possibilities for therapy and prognosis. The use of symptomatic delayed-action drugs (SYSADOA) is considered as the basic treatment of OA. Chondroitin sulfate (Chondroquard®) is one of the well established drugs, it has symptom- and structural-modifying properties. The article presents the results of studies confirming its effectiveness in reducing the severity of knee synovitis.

Study of Top Coal Partition and Key Delayed-Action Region for Horizontal Sublevel Top Coal Caving in Deeply Inclined Seam

Horizontal sublevel caving is the unique way to mine the steep and extra thick coal seams. We aim to determine reasonable height of horizontal subsection, which is crucial to ensure the output and safety of mining. For this aim, a theoretical model is established to determine the theoretical solution of elastic stress distribution in deeply inclined coal seam, and first principal stress expression is derived. And on this basis, related factors affecting the top coal caving property and key delayed-action areas are investigated. The results show that there are four zones in top coal, which are tensile failure zone (TFZ), tensile damage zone (TDZ), elastic zone (EZ), and compression-shear damage zone (CSDZ). The elevation of sublevel height cannot increase the release of top coal. It is necessary to determine the key region of affecting the top coal caving. The key delayed-action region (KDAR) consists of EZ and TFZ in top coal; the EZ and TFZ are type I and II KDAR, respectively, and type I is the key area of weakening top coal. In order to effectively weaken KDAR, opening coal channel of core region, and especially effectively obstructing the continuous moving upward of top coal caving arch structure with the help of weakening top coal body in type I KDAR, would promote caving property of top coal and improve the working face extraction rate.