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Prediction of forest parameters and carbon accounting under different fire regimes in Miombo woodlands, Niassa Special Reserve, Northern Mozambique
پیش بینی پارامترهای جنگلی و حسابداری کربن تحت رژیم های مختلف آتش سوزی در جنگل های میومبو، رزرو ویژه NIASSA، شمال موزامبیک-2021 Miombo woodlands are the most extensive dry forest type in southern Africa, covering ca. 1.9 million km2 across
seven countries. Fire is a key ecosystem process that has structured miombo for the last 200,000 years. However,
how fires affect the ecosystems functioning is not well understood. In this study, we used the individual-based
forest model called FORMIND to analyze the carbon balance in the miombo woodlands of Niassa Special Reserve
(NSR), northern Mozambique. The 42.000 km2 NSR represents the most important conservation area in
Mozambique (~31% of the total conservation area in the country) and of miombo woodlands worldwide. Longterm inventory data from 2004 to 2019 for NSR were used to calibrate FORMIND. The primary ecosystem
processes of this model are tree growth, mortality, regeneration, and competition. Fire is set as one of the main
factors that affect these processes, after the woodland reaches an equilibrium at 200 years of age. We also
calculated the Net Present Value (NPV) of carbon credits resulting from altering the fire regime (e.g., reducing or
eliminating fires). The FORMIND model successfully reproduced important characteristics of the woodlands
(aboveground biomass, stem size distribution and basal area). NPV estimates of above-ground woody biomass
carbon stocks were highly dependent on the woodland age. The maximum NPV estimates were generated for a
30-year project starting with 200 year old woodlands (the current forest age) at 192–1339 USD based on a
realistic range of carbon values (i.e., 3–20 USD MgCO2e− 1). While fire plays an important role in miombo
woodlands by reducing stock and changing species composition, its effects on the capacity of the woodland to
mitigate the effects of climate change varies depending on the age of stands. Our results show that FORMIND
model reliably reproduce the field inventory data, thus can be used to improve carbon accounting standards. We
recommend the development of a fire management system to sustain the miombo woodlands of NSR for multiple
reasons. NSR is a globally significant protected area, but perhaps more importantly it could become a regional
example for how to improve miombo woodland management. Given that miombo woodlands provide a myriad
of ecosystem services to rural Africans, investing in improving fire management could increase the benefits to
local communities. Altering fire regimes could improve habitat quality and promote greater resilience to climate
change while sequestering carbon. In addition, local employment opportunities in fire management could be
created via carbon financing from a carbon project. However, much more outreach and education will be needed
to local and national stakeholders for fire management to be perceived more positively and realize the potential
to generate multiple benefits for nature and people.
keywords: مدل GAP Formind | دینامیک اکوسیستم | حسابداری کربن | مدیریت آتش نشانی | خط مشی آتش | FORMIND gap model | Ecosystem dynamics | Carbon accounting | Fire management | Fire policy |
مقاله انگلیسی |
2 |
Restoration of calcareous grasslands: The early successional stage promotes biodiversity
ترمیم مراتع آهکی: مرحله اول موفقیت باعث تنوع زیستی می شود-2020 Land-use change has been identified as the most important factor responsible for the recent loss of biodiversity.
One major problem is the abandonment of management, especially in semi-natural grassland ecosystems.
Numerous restoration projects were, therefore, launched to counteract this development. However, the effects of
restoration are not yet fully understood. Especially the early successional stage, i.e. the composition of the
vegetation in the first years after the restoration measures, has received little attention probably due to its
supposedly low conservation value.
As study area, we selected the largest area of calcareous grasslands at the northern edge of the German
uplands. About 35 ha of formerly abandoned calcareous grasslands have been restored by cutting shrubs here in
the last eight years. Within the restored sites, 50 randomly chosen vegetation surveys were made and the results
were compared to 50 control plots.
Our study revealed that the value of the early successional stage for biodiversity conservation was previously
underestimated. Even though the target state – calcareous grassland – is far from being reached, the early
successional stage enhances the conservation value of calcareous grasslands by (i) increasing diversity at the
landscape scale, (ii) hosting numerous target species as well as (iii) contributing to a higher habitat quality and
heterogeneity.
Future restoration of calcareous grasslands should focus on sites with low nutrient content of the soil, a
shallow topsoil, and a warm microclimate. At such sites, the chances are greatest that species with a high nature
conservation value, i.e. characteristic species of calcareous grasslands as well as thermophilous fringe and
ruderal species, will re-establish. Keywords: Habitat quality | Heterogeneity | Host plant | Pollen source | Ruderal vegetation | Species richness |
مقاله انگلیسی |
3 |
Assessment and management of the North Brazil Shelf Large Marine Ecosystem
ارزیابی و مدیریت از شمال برزیل فلات بزرگ دریایی-2017 The North Brazil Shelf is a Large Marine Ecosystem (LME) that extends from the Caribbean Sea,
in Central America, to the Parnaiba River in Brazil, and includes six countries. The area is
dominated by the runoff of large rivers, including the Amazon and Orinoco, and by the intense
disturbance of sediment transport, tides and currents. The sea bed is formed mainly by mud in
shallow water, and by sand, mud, and gravel in deeper water. In terms of its biological
productivity, this LME can be considered oligotrophic, with stratified habitats. The main source
of nutrients of the euphotic layer is the local rivers and mangroves. Primary production has been
limited by light and rising temperatures in recent years, factors associated with a decrease in
marine primary productivity. However, the benthic fauna is very rich and unique, but poorly
known. More than 500 fish species have been recorded in this LME. Demersal fish and shrimp
are the main fishery resources in coastal and continental shelf waters. Fisheries account for more
than 600 million USD a year with a considerable diversity of methods and scales ranging from
very small to industrial. Seafood consumption is moderate to high in the local countries. Climate
changes, dam building, deforestation, pollution, overfishing, tourism and aquaculture are the
main threats to ecosystem productivity and habitat quality. Socioeconomic data are scant for this
LME. Development is concentrated near the cities and mouths of rivers. Traditional commu
nities in the coastal areas are culturally diverse, but invariably characterized by very low
socioeconomic conditions. The Gross Domestic Product of the local countries ranges from 7,500
USD per capita in Guyana to 32,600 USD per capita in Trinidad and Tobago. Profound problems
of governability are common to all six countries, and mean governance indicators reflect poor
performances in all cases. The main issues are an absence of effective rule of law, political
stability, and control of corruption. Fisheries are characterized by increasing effort and an
absence of sustainability. Most of the fishery stocks are either fully or over exploited. This
scenario can only be rectified by investments in marine protected areas and scientific research, as
well as the increased participation of fishers in the development and implementation of
management strategies and regulations.
Keywords: Fisheries | Governance | Ecosystem Based Management |
مقاله انگلیسی |