The effects of ditch dams on water‐level dynamics in tropical peatlands

Abstract

A significant proportion of tropical peatlands has been drained for agricultural purposes, resulting in severe degradation. Hydrological restoration, which usually involves blocking ditches, is therefore a priority. Nevertheless, the influence of ditch blocking on tropical peatland hydrological functioning is still poorly understood. We studied water-level dynamics using a combination of automated and manual dipwells, and also meteorological data during dry and wet seasons over 6 months at three locations in Sebangau National Park, Kalimantan, Indonesia. The locations were a forested peatland (Forested), a drained peatland with ditch dams (Blocked), and a drained peatland without ditch dams (Drained). In the dry season, water tables at all sites were deeper than the Indonesian regulatory requirement of 40 cm from the peat surface. In the dry season, the ditches were dry and water did not flow to them.The dry season water-table drawdown ratessolely due to evapotranspirationwere 9.3 mm day À1 at Forested, 9.6 mm day À1 at Blocked, but 12.7 mm day À1 at Drained. In the wet season, the proportion of time during which water tables in the wells were deeper than the 40 cm limit ranged between 16% and 87% at Forested, 0% at Blocked, and between 0% and 38% at Drained. In the wet season, water flowed from the peatland to ditches at Blocked and Drained. The interquartile range of hydraulic gradients between the lowest ditch outlet and the farthest well from ditches at Blocked was 3.7 Â 10 À4 to 7.8 Â 10 À4 m m À1 , but 1.9 Â 10 À3 to 2.6 Â 10 À3 m m À1 at Drained. Given the results from Forested, a water-table depth limit policy based on field data may be required, to reflect natural seasonal dynamics in tropical peatlands. Revised spatial designs of dams or bunds are also required, to ensure effective water-table management as part of tropical peatland restoration.

Agroforestry System as the Best Vegetation Management to Face Forest Degradation in Indonesia

“…Deep peat agroforestry systems (3-4m) with a combination of woody trees, non-timber trees and plantation crops contribute to a carbon stock of 3 tons ha -1 . Meanwhile, monoculture crops produce an average carbon stock of 0.8 tons ha -1 [25,26,27,28,29]. In addition, the application of agroforestry systems in dry land can increase the soil water content, overcome limited resources in dry areas while minimizing environmental damage [30,31].…”

The Influence of Transformational Leadership, Job Characteristics, Job Involvement, on Employee Performance through Work Engagement at PT. Virama Karya (Persero) East Java Branch

“…Transformational leadership is effective in achieving greater organizational performance by encouraging members to achieve common goals. Putra et al, (2021) ;Cahyandani, (2021) ;Heimerer, (2019) ;Wijaya, (2020) proves that transformational leadership has a positive effect on employee performance. Transformational leadership functions and roles and work attachments are essential in improving employee performance.…”

“…The higher the employee engagement of employees, the higher the resulting performance. But Putra et al, (2021) ;Wijaya, (2020) shows that there is a positive and insignificant influence between Employee Engagement on Employee Performance.…”

“…Transformational leadership functions and roles and work attachments are essential in improving employee performance. Putra et al, (2021) ;Wijaya, (2020); Salu & Hartijasi (2018) proving that transformational leadership has a positive effect on work engagement. Job Characteristic is an effort to identify the characteristics of the task of the job, how those characteristics are combined to form a different job with its relationship with motivation, job satisfaction, and employee performance (Oldham & Hackman, 2005).…”

Yield Potential of Shallots Bulbil Planting Materials with Liquid Organic Fertilizer Treatment out of Season

“…Indonesian farmers use consumption tubers as planting material because the use of shallot botanical seeds as planting material is still difficult in Indonesia. Shallots are long days that require more than 12 hours of sunlight to flower and produce seeds [4]. The use of consumption as planting material can promote diseases caused by pathogens such as viruses, fungi, bacteria, and nematodes [5].…”