Sustaining Medicinal Barks: Survival and Bark Regeneration of Amphipterygium adstringens (Anacardiaceae), a Tropical Tree under Experimental Debarking

Commercial harvests can threaten tree species harvested for their bark. Amphipterygium adstringens is a dioecious tree, endemic to the tropical dry forests of Mexico, where it is intensively harvested for its medicinal bark. Limited information hinders developing sustainable management strategies for A. adstringens. We assessed bark regeneration for male and female trees, and evaluated the effect of tree sex and diameter, debarking treatments and cutting seasons on bark regeneration and tree survival rates. Bark regeneration was higher for wet season harvested trees (vs. dry), regardless of their sex. Bark regeneration was higher on female than on male trees. There were significant interactions of harvest season, harvest treatment and tree sex diameter on bark regeneration and survival. Overall, the highest bark regeneration rates occurred in female trees with ≥20.1 cm diameter that were wet season harvested with a 50% debarking intensity. Consequently, wet season and intermediate intensity harvests appear to foster sound management, but we recommend against targeting exclusively a single demographic group (i.e., large female trees) due to potential negative impacts on species demography and bark supply. A grounded strategy for sustaining bark harvest would also need to take into account relevant aspects of local socio-ecological context, including harvest interactions with other land uses.

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Management implications derived from long term re-sight data: annual survival of the Maui Parrotbill Pseudonestor xanthophrys

Bird Conservation International ◽

10.1017/s0959270913000476 ◽

2013 ◽

Vol 24 (3) ◽

pp. 316-326 ◽

Cited By ~ 5

Author(s):

HANNA L. MOUNCE ◽

KELLY J. IKNAYAN ◽

DAVID L. LEONARD ◽

KIRSTY J. SWINNERTON ◽

JIM J. GROOMBRIDGE

Keyword(s):

Management Strategies ◽

Survival Rates ◽

Adult Survival ◽

Accurate Estimation ◽

Limited Information ◽

Adult Males ◽

Apparent Survival ◽

As Species ◽

Female Survival ◽

Species Specific

SummaryThe accurate estimation of key demographic parameters is invaluable for making decisions about the management of endangered wildlife but such estimates are often difficult to obtain. Parameters such as species-specific apparent survival rates are an important component in understanding population ecology and informing management decisions. The Maui Parrotbill Pseudonestor xanthophrys is a ‘Critically Endangered’ Hawaiian honeycreeper endemic to the Island of Maui. We used an 18-year encounter history dataset comprising 146 marked individuals to estimate apparent survival between sexes and age classes (juvenile, adult). A difference in survival rates between sexes was strongly supported; 0.72 ± 0.04 for adult females and 0.82 ± 0.03 for adult males. This difference may be a reflection of either reproductive costs or additional risks of incubation and brooding, such as depredation. We also found support for age-biased survival, but limited information for juveniles did not provide a well-supported model fit for our data (juvenile survival = 0.17 ± 0.15; adults = 0.78 ± 0.02). However, apparent adult survival was similar to that of other Hawaiian passerines (mean 0.78 ± 0.03, n = 16). These results suggest that efforts to prevent the extinction of this species may benefit from future management strategies focused on increasing female survival such as predator reduction.

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The effect of seasonal and human pressure on macrobenthic fauna in the Caroni Swamp Ramsar Site, Trinidad and Tobago

Revista de Biología Tropical ◽

10.15517/rbt.v66i3.31419 ◽

2018 ◽

Vol 66 (3) ◽

pp. 1101 ◽

Cited By ~ 1

Author(s):

Attish Kanhai ◽

Rahanna Juman

Keyword(s):

Anthropogenic Impacts ◽

Management Strategies ◽

Ecological Status ◽

Dry Season ◽

Biotic Index ◽

Ramsar Site ◽

Limited Information ◽

Wet Season ◽

Macrobenthic Fauna ◽

Caroni Swamp

Human pressures have placed many tropical estuaries in developing countries under increased levels of stress. The Caroni Swamp Ramsar Site, the largest mangrove swamp along the west coast of Trinidad, has been subjected to high levels of anthropogenic impacts including hydrological alteration and pollution from land-based sources since the 1920’s. While most of these impacts have been well documented, limited information exists on the macrobenthic communities in the swamp. This study addresses the paucity of information. The macrobenthic fauna in the main waterways of Caroni Swamp was sampled at 12 locations using a Van Veen 0.025m2 grab, once in the dry (April) and wet (August) season of 2015 with a total of 144 samples. The samples were sorted, counted and species were identified to the lowest possible taxonomic level. A total of 55 taxa were identified with polychaetes being the most abundant taxa. The ecological status of the macrobenthos was assessed using AZTI’s Marine Biotic Index (AMBI) and the multivariate-AMBI (M-AMBI). Physicochemical parameters were measured with a YSI multiparameter metre. Chemical analyses were also conducted on nitrates, nitrites, ammonia and reactive phosphates using standard methods. Overall, AMBI characterised the Caroni Swamp as “slightly disturbed” with a macrobenthic community of “poor” ecological status according to M-AMBI. Generally, the quality of the environment improves from the dry season to the wet season. However, seasonal variations in AMBI and M-AMBI were found to be site specific as some showed improvement in ecological status and macrozoobenthos quality while others showed degradation from the dry season to the wet season. The stations to the north of the swamp showed improvement from the dry season to the wet season while the opposite was observed in the more southern stations. One notable characteristic of the swamp was the high levels of pollutants, particularly ammonia, recorded in one of its major waterways, the Caroni River. This is in contrast to the other waterways within the swamp which experience much lower levels of pollutant input from land-based sources. The assessment of the Caroni Swamp using AMBI and M-AMBI may be useful for informing management strategies to conserve the wetland and improve environmental quality.

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Concepts and Practices for Improving Nitrogen Management for Vegetables

HortTechnology ◽

10.21273/horttech.2.1.121 ◽

1992 ◽

Vol 2 (1) ◽

pp. 121-125 ◽

Cited By ~ 9

Author(s):

George J. Hochmuth

Keyword(s):

Water Management ◽

Management Practices ◽

Management Strategies ◽

N Fertilization ◽

Nitrogen Management ◽

Land Grant ◽

Land Grant Universities ◽

Production Practices ◽

Negative Impacts ◽

N Management

Efficient N management practices usually involve many potential strategies, but always involve choosing the correct amount of N and the coupling of N management to efficient water management. Nitrogen management strategies are integral parts of improved production practices recommended by land-grant universities such as the Institute of Food and Agricultural Sciences, Univ. of Florida. This paper, which draws heavily on research and experience in Florida, outlines the concepts and technologies for managing vegetable N fertilization to minimize negative impacts on the environment.

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Farmers’ and Herders’ Perceptions on Rangeland Management in Two Agroecological Zones of Benin

Land ◽

10.3390/land10040425 ◽

2021 ◽

Vol 10 (4) ◽

pp. 425

Author(s):

Rodrigue Vivien Cao Diogo ◽

Luc Hippolyte Dossa ◽

Sèyi Fridaïus Ulrich Vanvanhossou ◽

Badirou Dine Abdoulaye ◽

Kossi Hélliot Dosseh ◽

...

Keyword(s):

Natural Resources ◽

Management Strategies ◽

Sustainable Use ◽

Negative Attitude ◽

Rangeland Management ◽

Mineral Fertilization ◽

The North ◽

Unused Land ◽

Agroecological Zones ◽

Sound Management

The sustainable use of rangelands in pastoral areas requires the inclusion of all stakeholders to develop sound management strategies. However, the role of these actors in the sustainable management of natural resources is still poorly understood. The present study aims to (i) assess the perception of farmers and herders of the risks and opportunities of transhumance on rangeland resource use and management, and to (ii) generate useful knowledge for the design and implementation of policies that favor the coexistence of these actors and reduce competition over rangeland resources use in Benin. To this end, interviews were conducted with 240 crop farmers and herders using a semi-structured questionnaire in two contrasting agroecological zones in the northern (Kandi) and the southern (Kétou) part of the country. Among the respondents, 64% of farmers in the North were agro-pastoralists (owning 10.6 ha of land and 10.7 cattle) and 36% were herders (keeping 45.8 cattle and cultivating about 3.7 ha of land). They perceived that communal rangelands were entirely degraded. In the South, 36% of respondents were agro-pastoralists (with 0.3 cattle and farming 4 ha of land) and 64% cattle herders (raising 45.3 cattle and farming 0.9 ha of land only). Of the herders, 50% kept cattle for more than 20 years, while agro-pastoralists had no previous experience in cattle herding. Cultivation practices among crop farmers, such as high use of mineral fertilization (23.8%) and bush fires for land clearing (22.5%), were reported in Kandi (North) and Kétou (South) as factors that might contribute to land degradation. However, these farmers perceived transhumance as a threat to the sustainable use of natural resources. In contrast, herders perceived transhumance as an opportunity to valorize unused land and increase the availability of manure to cropland. The prevalent negative attitude of crop farmers regarding transhumant herders increases the vulnerability of cattle herding in both regions. There is an urgent need of raising awareness concerning the mutual benefits provided by the coexistence of crop farmers with herders to promote participative rangeland management strategies. This may contribute towards coping with the current challenges of food insecurity and increasing climate variability as well as to reducing recurrent conflicts in the region.

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The Angler in the Environment: Social, Economic, Biological, and Ethical Dimensions

The Angler in the Environment: Social, Economic, Biological, and Ethical Dimensions ◽

10.47886/9781934874240.ch6 ◽

2011 ◽

Keyword(s):

Best Practices ◽

Best Practice ◽

Research Question ◽

Management Strategies ◽

Leisure Activity ◽

Quality Data ◽

Fish Stocks ◽

Catch And Release ◽

Practice Behaviors ◽

Negative Impacts

Abstract .—Recreational fishing is popular worldwide. However, the potential negative impacts of this leisure activity can influence the sustainability of targeted fish stocks. Although management strategies are frequently used to control the actions of anglers, participants themselves must ultimately be confident that changes in their behavior will lead to the conservation of recreational fish stocks before regulations are followed and best practices adopted. Directly involving recreational anglers in research used to quantify the value of best practices, such as in the case of catch and release, can help reinforce the notion among anglers that best practice behaviors facilitate conservation and sustainable exploitation. Using the framework of citizen science and the principles of experiential education (immersion, involvement, ownership, and legacy), we present a case study whereby recreational anglers were directly involved in research that tested how attributes of catch-and-release fishing for bonefish Albula spp. can influence the postrelease survival. By accompanying anglers to the shallow flats and actively involving them in hands-on research aimed at addressing relevant behaviors in the context of catch and release, such programs can promote an increased awareness and sense of personal ownership over the research question and the conservation benefits that it intends to facilitate. With data generated through direct involvement, the participation of recreational anglers in our research culminated in the development of a best practices brochure about catch and release for bonefish. It is our experience that research programs involving recreational anglers need to be well conceived and structured so as to adequately balance the quality of the experience for the participants with the need for generating quality data. Welldesigned “research angler” programs as a form of tourism or even ecotourism could help scientists not only to enhance their ability to conduct fisheries research, but also to broaden the impacts of their research program and the speed at which best practices are adopted.

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Invasive alien palm Pinanga coronata threatens native tree ferns in an oceanic island rainforest

Australian Journal of Botany ◽

10.1071/bt18088 ◽

2018 ◽

Vol 66 (8) ◽

pp. 647 ◽

Cited By ~ 2

Author(s):

Michael J. B. Dyer ◽

Gunnar Keppel ◽

Marika Tuiwawa ◽

Sainivalati Vido ◽

Hans Juergen Boehmer

Keyword(s):

Linear Models ◽

Management Strategies ◽

Ornamental Plants ◽

Native Plant ◽

Ecological Processes ◽

Mixed Effect ◽

Mixed Effect Models ◽

Tree Ferns ◽

Native Tree ◽

Negative Impacts

Invasive ornamental plants are a global problem that can have severe impacts on native biodiversity, especially on islands. To determine whether the invasive, ornamental ivory-cane palm Pinanga coronata could be displacing native biodiversity, we investigated its co-distribution with native tree ferns in a Fijian rainforest. We recorded the abundances of P. coronata and tree ferns and related these to environmental variables using linear models and generalised linear mixed-effect models (GLMMs). Distance to an introduction site was the most significant factor predicting the palm’s distribution and abundance, suggesting that its current distribution is limited by insufficient time for wider dispersal. P. coronata cover was strongly and negatively related with the abundance of native tree ferns and the palm may therefore be displacing native tree ferns. This relationship was strongest with tree fern seedlings and weakest with mature tree ferns, implying that the palm is preventing the establishment of native tree ferns. This study thus provides strong circumstantial evidence that P. coronata is progressively displacing native tree ferns by preventing seedling establishment and poses a severe threat to Fiji’s native biodiversity and ecological processes. Therefore, urgent management is required to control and prevent the further spread of P. coronata and its negative impacts on native plant biodiversity. Management should involve an initial feasibility study to determine the effectiveness of various management strategies, followed by targeted control and/or eradication campaigns and long-term monitoring. Ultimately, well implemented legislation to prevent the spread and introduction of P. coronata and other ornamental plants will be crucial to protect native biodiversity in Fiji and elsewhere.

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Trends in Survival of Patients with Primary Gastric Diffuse Large B-Cell Lymphoma: An Analysis of 7051 Cases in the SEER Database

Disease Markers ◽

10.1155/2018/7473935 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7

Author(s):

Pan-pan Liu ◽

Yi Xia ◽

Xi-wen Bi ◽

Yu Wang ◽

Peng Sun ◽

...

Keyword(s):

B Cell ◽

Cell Lymphoma ◽

Survival Rates ◽

Multivariable Analysis ◽

B Cell Lymphoma ◽

Treatment Modalities ◽

Seer Database ◽

Limited Information ◽

Large B Cell Lymphoma ◽

Large B Cell

Treatment modalities for primary gastric diffuse large B-cell lymphoma (PG-DLBCL) have changed significantly during the past decades. However, limited information on the trends of clinical outcome of PG-DLBCL patients has been reported. Here, we conducted a retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database to compare the survival trends of PG-DLBCL patients from 1973 to 2014. Patients were divided into 2 eras based on the year of diagnosis in relation to immunotherapy with the anti-CD20 antibody rituximab that was approved in 1997 and became a widely used drug in 2000. There was a significant improvement in survival among PG-DLBCL patients diagnosed in the 2001–2014 era (n=4186) compared to patients diagnosed in the 1973–2000 era (n=2865), with the 5-year overall survival rates of 53% and 47%, respectively (p=0.001). Multivariable analysis revealed that the 2001–2014 era (HR = 0.892, p=0.001) was associated with lower mortality and that patients of older age, Black race, advanced stage, and male gender were associated with poor prognosis. Although outcome of PG-DLBCL has significantly improved over time, more effective therapies are needed for older patients to further improve their survival.

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Implications for coral reef conservation of diver specialization

Environmental Conservation ◽

10.1017/s0376892906003419 ◽

2006 ◽

Vol 33 (4) ◽

pp. 353-363 ◽

Cited By ~ 54

Author(s):

PHILIP DEARDEN ◽

MICHELLE BENNETT ◽

RICK ROLLINS

Keyword(s):

Management Strategies ◽

Scuba Diving ◽

Effective Management ◽

Client Characteristics ◽

Reef Management ◽

Industry Competition ◽

History Of ◽

Conservation Activity ◽

Negative Impacts ◽

Over Time

One activity with potential to provide a direct incentive for reef conservation is scuba diving. In the absence of effective management, diving can also have negative impacts. This study shows how an understanding of diver specialization can be used to help manage diving and increase its effectiveness as an incentive-driven conservation activity. Surveys were used to assess motivations, satisfactions and dive history of divers in Phuket (Thailand) and categorize divers by degree of specialization. Highly specialized divers were more likely to be on a live-aboard trip than less specialized divers and placed greater importance on the characteristics of the dive itself rather than the trip. Less specialized divers put more emphasis on non-dive characteristics. Satisfaction levels differed significantly among specialization groups in terms of overall satisfaction with the dive experience, satisfactions compared with motivations and satisfactions with specific trip characteristics. Overall there was a decline in satisfaction levels with increasing specialization. These finding are compared to a wildlife tourism model that links impacts with client characteristics and suggests a displacement of specialists by generalists and changes in the limits of acceptable change (LAC) over time. The dive data supported this progression leading to increased industry competition and reduced opportunities to sustain a broad-based dive industry that will act as an incentive-driven mechanism for reef conservation. Specific actions related to reef access and zoning according to a diver opportunity spectrum (DOS), establishing LAC and monitoring programmes, enforcing safety and environmental regulations are suggested to promote a more sustainable approach to dive management. Social science insights can be used to aid reef management strategies and increase the potential for diving to contribute towards reef conservation.

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Anthropogenically-induced recharge in a semiarid mountain front context

10.5194/egusphere-egu2020-9267 ◽

2020 ◽

Author(s):

Houssne Bouimouass ◽

Younes Fakir ◽

Sarah Tweed ◽

Marc Leblanc

Keyword(s):

Stable Isotopes ◽

Hydrological Cycle ◽

Stream Water ◽

Groundwater Resources ◽

Management Strategies ◽

Wet Season ◽

Irrigation Area ◽

Groundwater Fluctuation ◽

Mountain Front ◽

Irrigation Practices

Mountain-fronts constitute important groundwater recharge areas in arid and semiarid regions. Mountain-front recharge processes are generally identified, in natural systems, as streamflow losses and subsurface inflow from the mountain block. However, another key recharge process is from irrigation practices; where mountain streamflow is distributed across the irrigated piedmont. In this study, coupled groundwater fluctuation measurements and stable isotopes (18O and 2H) were used to identify and compare the natural mountain-front recharge to the anthropogenically-induced irrigation recharge. Within the High-Atlas mountain front of the Ourika basin, Tensift, Central Morocco, the groundwater fluctuation mapping from the dry to wet season showed that recharge from irrigation waters was higher than the recharge along the streambed. Irrigation practices in the region divert more than 65% of the stream water, thereby reducing the potential for stream recharge. Due to the traditional irrigation practices, upstream crops are preferentially irrigated with stream water over downstream areas. In downstream areas irrigation is only via stream water during large flood events and is otherwise supplemented by groundwater resources. These changes in water resources used for irrigation practices between upstream and downstream areas are reflected in the spatio-temporal evolution of the stable isotopes of groundwater. In the upstream irrigation area, the groundwater stable isotope values (d18O: -8.4 &#8240; to -7.4 &#8240;) reflect recharge by the diverted stream water. In the downstream irrigation area, the groundwater isotope values are lower (d18O: -8.1 &#8240; to -8.4 &#8240;) due to recharge with floods.The results from this study particularly highlight that irrigation can deeply modify both the recharge processes and the water balance in the mountain front areas. Groundwater resources in such areas become reliant on the irrigation practices as an important source of recharge, and this anthropogenic modification of the hydrological cycle should be assessed and taken into consideration within climate change impacts and integrated water management strategies.

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Using population dynamics modelling to evaluate potential success of restoration: a case study of a Hawaiian vine in a changing climate

Environmental Conservation ◽

10.1017/s0376892914000204 ◽

2014 ◽

Vol 42 (1) ◽

pp. 20-30 ◽

Cited By ~ 3

Author(s):

TAMARA M. WONG ◽

TAMARA TICKTIN

Keyword(s):

Population Growth ◽

Growth Rates ◽

Key Management ◽

Demographic Data ◽

Population Decline ◽

Management Strategies ◽

Survival Rates ◽

Population Modelling ◽

Population Growth Rates

SUMMARYDemographic comparisons between wild and restored populations of at-risk plant species can reveal key management strategies for effective conservation, but few such studies exist. This paper evaluates the potential restoration success ofAlyxia stellata, a Hawaiian vine. Stage-structured matrix projection models that compared long-term and transient dynamics of wild versus restoredA. stellatapopulations, and restored populations under different levels of canopy cover, were built from demographic data collected over a four year period. Stochastic models of wild populations projected stable or slightly declining long-term growth rates depending on frequency of dry years. Projected long-term population growth rates of restored populations were significantly higher in closed than open canopy conditions, but indicated population decline under both conditions. Life table response experiments illustrated that lower survival rates, especially of small adults and juveniles, contributed to diminished population growth rates in restored populations. Transient analyses for restored populations projected short-term decline occurring even faster than predicted by asymptotic dynamics. Restored populations will not be viable over the long term under conditions commonly found in restoration projects and interventions will likely be necessary. This study illustrates how the combination of long-term population modelling and transient analyses can be effective in providing relevant information for plant demographers and restoration practitioners to promote self-sustaining native populations, including under future climates.

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